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  • 1.
    Ajalloueian, F.
    et al.
    Isfahan Univ Technol, Dept Text Engn, Ctr Excellence Appl Nanotechnol, Esfahan, Iran..
    Fransson, M.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology.
    Tavanai, H.
    Isfahan Univ Technol, Dept Text Engn, Ctr Excellence Appl Nanotechnol, Esfahan, Iran..
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Magnusson, Peetra
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology. Uppsala Univ, Dept Immunol Genet & Pathol IGP, Uppsala, Sweden..
    Arpanaei, A.
    Natl Inst Genet Engn & Biotechnol, Dept Ind & Environm Biotechnol, Tehran, Iran..
    Comparing PLGA and PLGA/Chitosan Nanofibers Seeded by Msc: A Cell-scaffold Interaction Study2015In: Tissue Engineering. Part A, ISSN 1937-3341, E-ISSN 1937-335X, Vol. 21, p. S406-S407Article in journal (Other academic)
  • 2.
    Ajalloueian, F.
    et al.
    Tech Univ Denmark, Copenhagen, Denmark..
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Fossum, M.
    Karolinska Inst, Stockholm, Sweden..
    Chronakis, I. S.
    Tech Univ Denmark, Copenhagen, Denmark..
    Integrated Micro/Nanofibrous PLGA-Collagen Scaffold: an Optimized Method for Plastic Compression of Collagen into PLGA Microfibers2015In: Tissue Engineering. Part A, ISSN 1937-3341, E-ISSN 1937-335X, Vol. 21, p. S347-S347Article in journal (Other academic)
  • 3.
    Ajalloueian, Fatemeh
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Fransson, Moa
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology.
    Tavanai, Hossein
    Massuni, Mohammad
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    LeBlanc, Katarina
    Arpanaei, Ayyoob
    Magnusson, Peetra
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology.
    Investigation of Human Mesenchymal Stromal Cells Cultured on PLGA orPLGA/Chitosan Electrospun Nanofibers2015In: Journal of Bioprocessing & Biotechniques, ISSN 2155-9821, Vol. 5, no 6, article id 230Article in journal (Refereed)
    Abstract [en]

    We compared the viability, proliferation, and differentiation of human Mesenchymal Stromal Cells (MSC)after culture on poly(lactic-co-glycolic acid) (PLGA) and PLGA/chitosan (PLGA/CH) hybrid scaffolds. We appliedconventional and emulsion electrospinning techniques, respectively, for the fabrication of the PLGA and PLGA/CH scaffolds. Electrospinning under optimum conditions resulted in an average fiber diameter of 166 ± 33 nmfor the PLGA/CH and 680 ± 175 nm for the PLGA scaffold. The difference between the tensile strength of thePLGA and PLGA/CH nanofibers was not significant, but PLGA/CH showed a significantly lower tensile modulusand elongation at break. However, it should be noted that the extensibility of the PLGA/CH was higher than thatof the nanofibrous scaffolds of pure chitosan. As expected, a higher degree of hydrophilicity was seen with PLGA/CH, as compared to PLGA alone. The biocompatibility of the PLGA and PLGA/CH scaffolds was compared usingMTS assay as well as analysis by scanning electron microscopy and confocal microscopy. The results showed thatboth scaffold types supported the viability and proliferation of human MSC, with significantly higher rates on PLGA/CH nanofibers. Nonetheless, an analysis of gene expression of MSC grown on either PLGA or PLGA/CH showed asimilar differentiation pattern towards bone, nerve and adipose tissues.

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  • 4.
    Ajalloueian, Fatemeh
    et al.
    Tech Univ Denmark, DTU Food, Nanobio Sci Res Grp, Lyngby, Denmark.
    Lemon, Greg
    Karolinska Inst, Dept Clin Sci Intervent & Technol CLINTEC, Stockholm, Sweden.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Chronakis, Ioannis S.
    Tech Univ Denmark, DTU Food, Nanobio Sci Res Grp, Lyngby, Denmark.
    Fossum, Magdalena
    Karolinska Inst, Dept Womens & Childrens Hlth, Stockholm, Sweden; Karolinska Inst, Ctr Mol Med, CMM 02, Stockholm, Sweden; Karolinska Univ Hosp, Astrid Lindgren Childrens Hosp, Dept Paediat Surg, Sect Urol, Stockholm, Sweden.
    Bladder biomechanics and the use of scaffolds for regenerative medicine in the urinary bladder2018In: Nature reviews. Urology, ISSN 1759-4812, E-ISSN 1759-4820, Vol. 15, no 3, p. 155-174Article, review/survey (Refereed)
    Abstract [en]

    The urinary bladder is a complex organ with the primary functions of storing urine under low and stable pressure and micturition. Many clinical conditions can cause poor bladder compliance, reduced capacity, and incontinence, requiring bladder augmentation or use of regenerative techniques and scaffolds. To replicate an organ that is under frequent mechanical loading and unloading, special attention towards fulfilling its biomechanical requirements is necessary. Several biological and synthetic scaffolds are available, with various characteristics that qualify them for use in bladder regeneration in vitro and in vivo, including in the treatment of clinical conditions. The biomechanical properties of the native bladder can be investigated using a range of mechanical tests for standardized assessments, as well as mathematical and computational bladder biomechanics. Despite a large body of research into tissue engineering of the bladder wall, some features of the native bladder and the scaffolds used to mimic it need further elucidation. Collection of comparable reference data from different animal models would be a helpful tool for researchers and will enable comparison of different scaffolds in order to optimize characteristics before entering preclinical and clinical trials.

  • 5.
    Ajalloueian, Fatemeh
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Tavanai, Hossein
    Hilborn, Jons
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Donzel-Gargand, Olivier
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Leifer, Klaus
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Wickham, Abeni
    Arpanaei, Ayyoob
    Emulsion Electrospinning as an Approach to Fabricate PLGA/Chitosan Nanofibers for Biomedical Applications2014In: BioMed Research International, ISSN 2314-6133, Vol. 2014, p. 475280-Article in journal (Refereed)
    Abstract [en]

    Novel nanofibers from blends of polylactic-co-glycolic acid (PLGA) and chitosan have been produced through an emulsion electrospinning process. The spinning solution employed polyvinyl alcohol (PVA) as the emulsifier. PVA was extracted from the electrospun nanofibers, resulting in a final scaffold consisting of a blend of PLGA and chitosan. The fraction of chitosan in the final electrospun mat was adjusted from 0 to 33%. Analyses by scanning and transmission electron microscopy show uniform nanofibers with homogenous distribution of PLGA and chitosan in their cross section. Infrared spectroscopy verifies that electrospun mats contain both PLGA and chitosan. Moreover, contact angle measurements show that the electrospun PLGA/chitosanmats are more hydrophilic than electrospun mats of pure PLGA. Tensile strengths of 4.94 MPa and 4.21 MPa for PLGA/chitosan in dry and wet conditions, respectively, illustrate that the polyblend mats of PLGA/chitosan are strong enough for many biomedical applications. Cell culture studies suggest that PLGA/chitosan nanofibers promote fibroblast attachment and proliferation compared to PLGA membranes. It can be assumed that the nanofibrous composite scaffold of PLGA/chitosan could be potentially used for skin tissue reconstruction.

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  • 6.
    Ajalloueian, Fatemeh
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Zeiai, S.
    Fossum, M.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    A bedside collagen-PLGA nanofibrous construct for autologous transplantation of minced bladder mucosal2012In: Journal of Tissue Engineering and Regenerative Medicine, ISSN 1932-6254, Vol. 6, no suppl 1, p. 128-128Article in journal (Other academic)
    Abstract [en]

    Introduction: Bladder regeneration using minced bladder mucosa is an alternative to costly and time-consuming conventional in vitro culturing of urothelial cells. In this method, the uroepithelium expands in vivo and the patient body appears as an incubator. With our preliminary successes, designing an appropriate scaffold that supports in vivo cell expansion and surgical handling in a clinical setting was our aim. This study, investigates cell expansion in a hybrid construct of collagen/poly (lactic-co-glycolide)(PLGA).

    Materials and methods: An electrospun PLGA mat was placed on a semi-gel collagen inside a mold and covered with a second collagen layer. After gel formation, minced particles of pig bladder mucosa were seeded on the hybrid construct and then processed by plastic compression (PC). The scaffolds were incubated for 2, 4 and 6 weeks in vitro for further studies.

    Results: Tensile tests show an increase in tensile strength of 0.6 ± 0.1 MPa in PC collagen to 3.6 ± 1.1 MPa in hybrid construct. Morphological studies, histological staining and SEM show that the construct has kept its integrity during the time and proliferated urothelial cells have reached confluence after 4 weeks and a multi-layered urothelium after 6 weeks.

    Conclusion: We have designed a mechanically robust scaffold that permits surgical handling and tissue expansion in vivo. The construct is easy-to-use for clinical application in an ordinary surgical operating theater for bladder regeneration.

  • 7.
    Ajalloueian, Fatemeh
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Zeiai, Said
    Fossum, Magdalena
    Hilborn, Jöns G.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Constructs of electrospun PLGA, compressed collagen and minced urothelium for minimally manipulated autologous bladder tissue expansion2014In: Biomaterials, ISSN 0142-9612, E-ISSN 1878-5905, Vol. 35, no 22, p. 5741-5748Article in journal (Refereed)
    Abstract [en]

    Bladder regeneration based on minced bladder mucosa in vivo expansion is an alternative to in vitro culturing of urothelial cells. Here, we present the design of a hybrid, electrospun poly(lactic-co-glycolide) (PLGA) - plastically compressed (PC) collagen scaffold that could allow in vivo bladder mucosa expansion. Optimisation of electrospinning was performed in order to obtain increased pore sizes and porosity to consolidate the construct and to support neovascularisation and tissue ingrowth. Tensile tests showed an increase in average tensile strength from 0.6 MPa for PC collagen to 3.57 MPa for the hybrid construct. The optimised PLGA support scaffold was placed between two collagen gels, and the minced tissue was distributed either on top or both on top and inside the construct prior to PC; this was then cultured for up to four weeks. Morphology, histology and SEM demonstrated that the construct maintained its integrity throughout cell culture. Cells from minced tissue migrated, expanded and re-organised to a confluent cell layer on the top of the construct after two weeks and formed a multilayered urothelium after four weeks. Cell morphology and phenotype was typical for urothelial mucosa during tissue culture. (C) 2014 Elsevier Ltd. All rights reserved.

  • 8.
    Ajalloueian, Fatemeh
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Zeiai, Said
    Rojas, Ramiro
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Fossum, Magdalena
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    One-Stage Tissue Engineering of Bladder Wall Patches for an Easy-To-Use Approach at the Surgical Table2013In: Tissue Engineering. Part C, Methods, ISSN 1937-3384, E-ISSN 1937-3392, Vol. 19, no 9, p. 688-696Article in journal (Refereed)
    Abstract [en]

    We present a method for producing a cell-scaffold hybrid construct at the bedside. The construct is composed of plastic-compressed collagen together with a poly(e-caprolactone) (PCL)-knitted mesh that yields an integrated, natural-synthetic scaffold. This construct was evaluated by seeding of minced bladder mucosa, followed by proliferation in vitro. High mechanical strength in combination with a biological environment suitable for tissue growth was achieved through the creation of a hybrid construct that showed an increased tensile strength (17.9 +/- 2.6 MPa) when compared to plastic-compressed collagen (0.6 +/- 0.12 MPa). Intimate contact between the collagen and the PCL fabric was required to ensure integrity without delamination of the construct. This contact was achieved by surface alkaline hydrolysis of the PCL, followed by adsorption of poly(vinyl) alcohol. The improvement in hydrophilicity of the PCL-knitted mesh was confirmed through water contact angle measurements, and penetration of the collagen into the mesh was evaluated by scanning electron microscopy (SEM). Particles of minced bladder mucosa tissue were seeded onto this scaffold, and the proliferation was followed for 6 weeks in vitro. Results obtained from phase contrast microscopy, SEM, and histological staining indicated that cells migrated from the minced tissue particles and reorganized on the scaffold. Cells were viable and proliferative, with morphological features characteristic of urothelial cells. Proliferation reached the point at which a multilayer with a resemblance to stratified urothelium was achieved. This successful method could potentially be used for in vivo applications in reconstructive urology as an engineered autologous tissue transplant without the requirement for in vitro culture before transplantation.

  • 9.
    Andersson, Edvin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Sångeland, Christofer
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Berggren, Elin
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Condensed Matter Physics of Energy Materials.
    Johansson, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Inorganic Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Kühn, Danilo
    Lindblad, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Condensed Matter Physics of Energy Materials.
    Mindemark, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Hahlin, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Early-Stage Decomposition of Solid Polymer Electrolytes in Li-Metal Batteries2021In: Journal of Materials Chemistry, ISSN 0959-9428, E-ISSN 1364-5501, Vol. 9, no 39Article in journal (Refereed)
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  • 10.
    Aulin, C.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Jensen-Waern, M.
    Ekman, S.
    Hagglund, M.
    Engstrand, T.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Hedenqvist, P.
    Cartilage repair of experimentally 11 induced osteochondral defects in New Zealand White rabbits2013In: Laboratory Animals, ISSN 0023-6772, E-ISSN 1758-1117, Vol. 47, no 1, p. 58-65Article in journal (Refereed)
    Abstract [en]

    Articular cartilage has a limited capacity for self-repair in adult humans, and methods used to stimulate regeneration often result in re-growth of fibrous cartilage, which has lower durability. No current treatment option can provide complete repair. The possibility of growth factor delivery into the joint for cartilage regeneration after injury would be an attractive treatment option. A full thickness osteochondral defect of 4 mm in diameter and 2 mm deep was created by mechanical drilling in the medial femoral condyle in 20 female adult New Zealand White rabbits. In an attempt to improve regeneration a hyaluronic hydrogel system, with or without bone morphogenetic protein-2 (BMP-2) was delivered intraarticularly. The contralateral joint defect was treated with saline as control. Throughout the study, rabbits were clinically examined and after 12 (n = 6) or 24 (n = 9) weeks, the rabbits were euthanized and the joints evaluated by histology. The defects healed with fibrocartilage like tissue, and the filling of the defects ranged from less than 25% to complete. The healing of the defects varied both inter- and intra-group wise. Treatment with hyaluronan gel with or without BMP-2 had no effect on cartilage regeneration compared with controls. Instead, severe ectopic bone formation was found in seven joints treated with BMP-2. In conclusion, the present study shows that neither treatment with hyaluronic gel alone, nor in combination with BMP-2, improves the healing of an induced cartilage defect in rabbits. It further shows that BMP-2 can induce ectopic bone formation, which severely affects the functionality of the joint.

  • 11. Backly, R. E.
    et al.
    Todeschi, M. R.
    Varghese, Oommen
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Cancedda, R.
    Mastrogiacomo, M.
    Host cell recruitment patterns by BMP-2 releasing hyaluronic acid gels in a mouse subcutaneous model2014In: Journal of Tissue Engineering and Regenerative Medicine, ISSN 1932-6254, E-ISSN 1932-7005, Vol. 8, p. 65-65Article in journal (Other academic)
  • 12.
    Badali, Elham
    et al.
    Kharazmi Univ, Fac Chem, POB 15719-14911, Tehran, Iran..
    Hosseini, Mahshid
    Iran Univ Med Sci IUMS, Hazrat Rasoul Akram Hosp, Skull Base Res Ctr, Senses Inst 5, Tehran, Iran..
    Mohajer, Maryam
    Iran Univ Med Sci IUMS, Hazrat Rasoul Akram Hosp, Skull Base Res Ctr, Senses Inst 5, Tehran, Iran..
    Hassanzadeh, Sajad
    Iran Univ Med Sci IUMS, Hazrat Rasoul Akram Hosp, Skull Base Res Ctr, Senses Inst 5, Tehran, Iran..
    Saghati, Sepideh
    Tabriz Univ Med Sci, Fac Adv Med Sci, Dept Tissue Engn, Tabriz, Iran..
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Khanmohammadi, Mehdi
    Iran Univ Med Sci IUMS, Hazrat Rasoul Akram Hosp, Skull Base Res Ctr, Senses Inst 5, Tehran, Iran..
    Enzymatic Crosslinked Hydrogels for Biomedical Application2021In: Polymer science, ISSN 0965-545X, Vol. 63, no SUPPL 1, p. S1-S22Article, review/survey (Refereed)
    Abstract [en]

    Self-assembled structures primarily arise through enzyme-regulated phenomena in nature under persistent conditions. Enzymatic reactions are one of the main biological processes constructing supramolecular hydrogel networks required for biomedical applications. Such enzymatic processes provide a unique opportunity to integrate hydrogel formation. In most cases, the structure and substrates of hydrogels are adjusted by enzyme catalysis due to enzymes' chemo-, regio- and stereo-selectivity. Such hydrogels processed using various enzyme schemes showed remarkable characteristics as dynamic frames for cells, bioactive molecules, and drugs in tissue engineering, drug delivery, and regenerative medicine. The enzyme-mediated crosslinking hydrogels mimic the extracellular matrices by displaying unique physicochemical properties and functionalities such as water-retention capacity, biodegradability, biocompatibility, biostability, bioactivity, optoelectronic properties, self-healing ability, and shape memory ability. In recent years, many enzymatic systems investigated polymer crosslinking. Herein, we review efficient strategies for enzymatic hydrogelation, including hydrogel synthesis and chemistry, and demonstrate their applicability in biomedical systems. Furthermore, the advantages, challenges, and prospects of enzymatic-crosslinkable hydrogels are discussed. The results of biocompatible hydrogel products show that these crosslinking mechanisms can fulfill requirements for a variety of biomedical applications, including tissue engineering, wound healing, and drug delivery.

  • 13.
    Bahadorikhalili, Saeed
    et al.
    Univ Tehran Med Sci, Endocrinol & Metab Clin Sci Inst, Endocrinol & Metab Res Ctr, Tehran, Iran..
    Divar, Masoumeh
    Shiraz Univ Med Sci, Pharmaceut Sci Res Ctr, Shiraz, Iran..
    Damghani, Tahereh
    Shiraz Univ Med Sci, Sch Pharm, Dept Med Chem, Shiraz, Iran..
    Moeini, Fatemeh
    Zand Inst Higher Educ, Dept Biol, Fac Sci, Shiraz, Iran..
    Ghassamipour, Soheila
    Islamic Azad Univ, Marvdasht Branch, Dept Chem, Marvdasht, Iran..
    Iraji, Aida
    Shiraz Univ Med Sci, Stem Cells Technol Res Ctr, Shiraz, Iran.;Shiraz Univ Med Sci, Med & Nat Prod Chem Res Ctr, Shiraz, Iran..
    Miller, Max A.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Larijani, Bagher
    Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.
    Mahdavi, Mohammad
    Univ Tehran Med Sci, Endocrinol & Metab Clin Sci Inst, Endocrinol & Metab Res Ctr, Tehran, Iran..
    N-sulfonyl ketenimine as a versatile intermediate for the synthesis of heteroatom containing compounds2021In: Journal of Organometallic Chemistry, ISSN 0022-328X, E-ISSN 1872-8561, Vol. 939, article id 121773Article, review/survey (Refereed)
    Abstract [en]

    The introduction of more facile and atom efficient methods for the synthesis of organic linear and cyclic compounds is the aim of various researchers worldwide. N-sulfonyl ketenimine is an interesting intermediate in modern organic synthesis. N-sulfonyl ketenimine is capable of selective production of various heteroatom containing compounds, based on the functional groups in the structure of this intermediate. Several linear and cyclic compounds are synthesized from this intermediate. In this review, the role of N-sulfonyl ketenimine is studied as an intermediate in several organic syntheses.

  • 14.
    Balion, Zbigniev
    et al.
    Lithuanian Univ Hlth Sci, Inst Pharmaceut Technol, Sukileliu Ave 13, LT-50162 Kaunas, Lithuania.;Lithuanian Univ Hlth Sci, Neurosci Inst, Eiveniu Str 4, LT-50161 Kaunas, Lithuania..
    Cepla, Vytautas
    Ferentis UAB, Savanoriu 231, LT-02300 Vilnius, Lithuania.;Ctr Phys Sci & Technol, Dept Nanoengn, Savanoriu 231, LT-02300 Vilnius, Lithuania..
    Svirskiene, Natasa
    Lithuanian Univ Hlth Sci, Neurosci Inst, Eiveniu Str 4, LT-50161 Kaunas, Lithuania..
    Svirskis, Gytis
    Lithuanian Univ Hlth Sci, Neurosci Inst, Eiveniu Str 4, LT-50161 Kaunas, Lithuania..
    Druceikaite, Kristina
    Ferentis UAB, Savanoriu 231, LT-02300 Vilnius, Lithuania..
    Inokaitis, Hermanas
    Lithuanian Univ Hlth Sci, Inst Anat, Mickeviciaus 9, LT-43074 Kaunas, Lithuania..
    Rusteikaite, Justina
    Lithuanian Univ Hlth Sci, Inst Pharmaceut Technol, Sukileliu Ave 13, LT-50162 Kaunas, Lithuania..
    Masilionis, Ignas
    Ferentis UAB, Savanoriu 231, LT-02300 Vilnius, Lithuania..
    Stankeviciene, Gintare
    Ferentis UAB, Savanoriu 231, LT-02300 Vilnius, Lithuania.;Ctr Phys Sci & Technol, Dept Nanoengn, Savanoriu 231, LT-02300 Vilnius, Lithuania..
    Jelinskas, Tadas
    Ferentis UAB, Savanoriu 231, LT-02300 Vilnius, Lithuania..
    Ulcinas, Arturas
    Ctr Phys Sci & Technol, Dept Nanoengn, Savanoriu 231, LT-02300 Vilnius, Lithuania..
    Samanta, Ayan
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Valiokas, Ramunas
    Ferentis UAB, Savanoriu 231, LT-02300 Vilnius, Lithuania.;Ctr Phys Sci & Technol, Dept Nanoengn, Savanoriu 231, LT-02300 Vilnius, Lithuania..
    Jekabsone, Aiste
    Lithuanian Univ Hlth Sci, Inst Pharmaceut Technol, Sukileliu Ave 13, LT-50162 Kaunas, Lithuania.;Lithuanian Univ Hlth Sci, Neurosci Inst, Eiveniu Str 4, LT-50161 Kaunas, Lithuania..
    Cerebellar Cells Self-Assemble into Functional Organoids on Synthetic, Chemically Crosslinked ECM-Mimicking Peptide Hydrogels2020In: Biomolecules, E-ISSN 2218-273X, Vol. 10, no 5, article id 754Article in journal (Refereed)
    Abstract [en]

    Hydrogel-supported neural cell cultures are more in vivo-relevant compared to monolayers formed on glass or plastic substrates. However, there is a lack of synthetic microenvironment available for obtaining standardized and easily reproducible cultures characterized by tissue-mimicking cell composition, cell-cell interactions, and functional networks. Synthetic peptides representing the biological properties of the extracellular matrix (ECM) proteins have been reported to promote the adhesion-driven differentiation and functional maturation of neural cells. Thus, such peptides can serve as building blocks for engineering a standardized, all-synthetic environment. In this study, we have compared the effect of two chemically crosslinked hydrogel compositions on primary cerebellar cells: collagen-like peptide (CLP), and CLP with an integrin-binding motif arginine-glycine-aspartate (CLP-RGD), both conjugated to polyethylene glycol molecular templates (PEG-CLP and PEG-CLP-RGD, respectively) and fabricated as self-supporting membranes. Both compositions promoted a spontaneous organization of primary cerebellar cells into tissue-like clusters with fast-rising Ca2+ signals in soma, reflecting action potential generation. Notably, neurons on PEG-CLP-RGD had more neurites and better synaptic efficiency compared to PEG-CLP. For comparison, poly-L-lysine-coated glass and plastic surfaces did not induce formation of such spontaneously active networks. Additionally, contrary to the hydrogel membranes, glass substrates functionalized with PEG-CLP and PEG-CLP-RGD did not sufficiently support cell attachment and, subsequently, did not promote functional cluster formation. These results indicate that not only chemical composition but also the hydrogel structure and viscoelasticity are essential for bioactive signaling. The synthetic strategy based on ECM-mimicking, multifunctional blocks in registry with chemical crosslinking for obtaining tissue-like mechanical properties is promising for the development of fast and well standardized functional in vitro neural models and new regenerative therapies.

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  • 15. Barman, Jharna
    et al.
    Gurav, Deepanjali
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Oommen, Oommen Podiyan
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Varghese, Oommen P.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    2 '-N-Guanidino, 4 '-C-ethylene bridged thymidine (GENA-T) modified oligonucleotide exhibits triplex formation with excellent enzymatic stability2015In: RSC Advances, E-ISSN 2046-2069, Vol. 5, no 16, p. 12257-12260Article in journal (Refereed)
    Abstract [en]

    Here we present the synthesis and characterization of a new 2'-N-Guanidino, 4'-C-ethylene bridged thymidine (GENA-T) modified oligonucleotide possessing North-locked sugar conformation. Incorporation of GENA-T nucleotide though did not change the thermal stability of the oligonucleotides toward the complementary RNA; it significantly increased the stability of the parallel triplex at pH 7. The melting temperature of the triplex was increased by +9.5 degrees C as compared to that of the isosequential unmodified sequence. Moreover this modification imparted exceptional nuclease stability to the oligonucleotides for over 33 h. This study clearly demonstrates that GENA-T modified oligonucleotides could improve triplex formation with phenomenal enzymatic stability and could be used for various biomedical applications.

  • 16.
    Becker, Juliane
    et al.
    DEUTSCHES KREBSFORSCHUNGSZENTRUM, RUPRECHT-KARLS-UNIVERSITAT HEIDELBERG.
    Jäschke, Andres
    DEUTSCHES KREBSFORSCHUNGSZENTRUM, RUPRECHT-KARLS-UNIVERSITAT HEIDELBERG.
    Samanta, Ayan
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. DEUTSCHES KREBSFORSCHUNGSZENTRUM, RUPRECHT-KARLS-UNIVERSITAT HEIDELBERG.
    Wiessler, Manfred
    DEUTSCHES KREBSFORSCHUNGSZENTRUM, RUPRECHT-KARLS-UNIVERSITAT HEIDELBERG.
    MULTIPLE ORTHOGONAL LABELLING OF OLGONUCLEOTIDES2016Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    In Summary, the present invention concerns a method for multiple orthogonal labelling of oligonucleotides, preferably RNA or DNA, by simultaneously performing the inverse Diels-Alder reaction (DAinv) and the copper-catalyzed click reaction (CuAAC), wherein the method is employed in a single step by just adding the different reaction components together and incubating the aqueous reaction mixture prefer ably for one hour at room temperature. In detail, the reaction components are one or more N-modified labels, a copper compound, a stabilizing ligand, a reducing agent and one or more electron-deficient label-modified dienes that are added together with an at least double-modified oligonucleotide having one more nucleotides containing one or more N3-re active groups and one or more electron-rich dienophiles, wherein a terminal alkyne moiety is preferably used as N3-re active group(s) and afrans-cyclooctene moiety or norbornene is preferably used as electron-rich dienophile(s), more pref erably frans-cyclooctene. Therefore, the present invention provides a one-pot method for post-synthetic multiple orthogonal labeling of oligonucleotides, which allows the site-specific introduction of more than one label, preferably of at least two labels into oligonucleotides after solid-phase synthesis, wherein the DAinv takes place on the dienophile modification only and the CuAAC selectively takes place on the N3-reactive group modification.

    Download full text (pdf)
    MULTIPLE ORTHOGONAL LABELLING OF OLGONUCLEOTIDES
  • 17.
    Bergfelt, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Block Copolymer Electrolytes: Polymers for Solid-State Lithium Batteries2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The use of solid polymer electrolytes (SPEs) for lithium battery devices is a rapidly growing research area. The liquid electrolytes that are used today are inflammable and harmful towards the battery components. The adoption of SPEs could drastically improve this situation, but they still suffer from a too low performance at ambient temperatures for most practical applications. However, by increasing the operating temperature to between 60 °C and 90 °C, the electrolyte performance can be drastically increased. The drawback of this approach, partly, is that parasitic side reactions become noticeable at these elevated temperatures, thus affecting battery lifetime and performance. Furthermore, the ionically conductive polymer loses its mechanical integrity, thus triggering a need for an external separator in the battery device.

    One way of combining both mechanical properties and electrochemical performance is to design block copolymer (BCP) electrolytes, that is, polymers that are tailored to combine one ionic conductive block with a mechanical block, into one polymer. The hypothesis is that the BCP electrolytes should self-assemble into well-defined microphase separated regions in order to maximize the block properties. By varying monomer composition and structure of the BCP, it is possible to design electrolytes with different battery device performance. In Paper I and Paper II two types of methacrylate-based triblock copolymers with different mechanical blocks were synthesized, in order to evaluate morphology, electrochemical performance, and battery performance. In Paper III and Paper IV a different strategy was adopted, with a focus on diblock copolymers. In this strategy, the ethylene oxide was replaced by poly(e-caprolactone) and poly(trimethylene carbonate) as the lithium-ion dissolving group. The investigated mechanical blocks in these studies were poly(benzyl methacrylate) and polystyrene. The battery performance for these electrolytes was superior to the methacrylate-based battery devices, thus resulting in stable battery cycling at 40 °C and 30 °C.

    List of papers
    1. d8-poly(methyl methacrylate)-poly[(oligo ethylene glycol) methyl ether methacrylate] tri-block-copolymer electrolytes: Morphology, conductivity and battery performance
    Open this publication in new window or tab >>d8-poly(methyl methacrylate)-poly[(oligo ethylene glycol) methyl ether methacrylate] tri-block-copolymer electrolytes: Morphology, conductivity and battery performance
    Show others...
    2017 (English)In: Polymer, ISSN 0032-3861, E-ISSN 1873-2291, Vol. 131, p. 234-242Article in journal (Refereed) Published
    Abstract [en]

    A series of deuterated tri-block copolymers with the general structure d(8)-PMMA-POEGMA-d(8)-PMMA, with variation in d(8)-PMMA chain length, were synthesized using sequential controlled radical polymerization (ATRP). Solid polymer electrolytes (SPEs) were produced by blending tri-block copolymers and lithium bis(trifluoro methylsulfonate) (LiTFSI). Small-angle neutron scattering (SANS) was used to study the bulk morphology of the deuterated tri-block copolymer electrolyte series at 25 degrees C, 60 degrees C and 95 degrees C. The lack of a second T-g in DSC analysis together with modelling with the random phase approximation model (RPA) confirmed that the electrolytes are in the mixed state, with negative Flory-Huggins interaction parameters. AC impedance spectroscopy was used to study the ionic conductivity of the SPE series in the temperature interval 30 degrees C-90 degrees C, and a battery device was constructed to evaluate a 25 wt% d(8)-PMMA electrolyte. The Li | SPE | LiFePO4 cell cycled at 60 degrees C, giving a discharge capacity of 120 mAh g(-1), while cyclic voltammetry showed that the SPE was stable at 60 degrees C.

    National Category
    Polymer Chemistry
    Identifiers
    urn:nbn:se:uu:diva-337667 (URN)10.1016/j.polymer.2017.10.044 (DOI)000415014300026 ()
    Funder
    Swedish Research Council
    Available from: 2018-01-03 Created: 2018-01-03 Last updated: 2018-02-22Bibliographically approved
    2. Poly(benzyl methacrylate)-Poly[(oligo ethylene glycol) methyl ether methacrylate] Triblock-Copolymers as Solid Electrolyte for Lithium Batteries
    Open this publication in new window or tab >>Poly(benzyl methacrylate)-Poly[(oligo ethylene glycol) methyl ether methacrylate] Triblock-Copolymers as Solid Electrolyte for Lithium Batteries
    2018 (English)In: Solid State Ionics, ISSN 0167-2738, E-ISSN 1872-7689, Vol. 321, p. 55-61Article in journal (Refereed) Published
    Abstract [en]

    A triblock copolymer of benzyl methacrylate and oligo(ethylene glycol) methyl ether methacrylate was polymerized to form the general structure PBnMA-POEGMA-PBnMA, using atom transfer radical polymerization (ATRP). The block copolymer (BCP) was blended with lithium bis(trifluoro methylsulfonate) (LiTFSI) to form solid polymer electrolytes (SPEs). AC impedance spectroscopy was used to study the ionic conductivity of the SPE series in the temperature interval 30 °C to 90 °C. Small-angle X-ray scattering (SAXS) was used to study the morphology of the electrolytes in the temperature interval 30 °C to 150 °C. By using benzyl methacrylate as a mechanical block it was possible to tune the microphase separation by the addition of LiTFSI, as proven by SAXS. By doing so the ionic conductivity increased to values higher than ones measured on a methyl methacrylate triblock copolymer-based electrolyte in the mixed state, which was investigated in an earlier paper by our group. A Li|SPE|LiFePO4 half-cell was constructed and cycled at 60 °C. The cell produced a discharge capacity of about 100 mAh g−1 of LiFePO4 at C/10, and the half-cell cycled for more than 140 cycles.

    National Category
    Polymer Chemistry
    Research subject
    Chemistry with specialization in Polymer Chemistry
    Identifiers
    urn:nbn:se:uu:diva-340851 (URN)10.1016/j.ssi.2018.04.006 (DOI)000437372200009 ()
    Funder
    Swedish Energy AgencyStandUp
    Available from: 2018-02-04 Created: 2018-02-04 Last updated: 2018-10-11Bibliographically approved
    3. ε-Caprolactone-based solid polymer electrolytes for lithium-ion batteries: synthesis, electrochemical characterization and mechanical stabilization by block copolymerization
    Open this publication in new window or tab >>ε-Caprolactone-based solid polymer electrolytes for lithium-ion batteries: synthesis, electrochemical characterization and mechanical stabilization by block copolymerization
    Show others...
    2018 (English)In: RSC Advances, E-ISSN 2046-2069, Vol. 8, no 30, p. 16716-16725Article in journal (Refereed) Published
    Abstract [en]

    In this work, three types of polymers based on epsilon-caprolactone have been synthesized: poly(epsilon-caprolactone), polystyrene-poly(epsilon-caprolactone), and polystyrene-poly(epsilon-caprolactone-r-trimethylene carbonate) (SCT), where the polystyrene block was introduced to improve the electrochemical and mechanical performance of the material. Solid polymer electrolytes (SPEs) were produced by blending the polymers with 10-40 wt% lithium bis(trifluoromethane) sulfonimide (LiTFSI). Battery devices were thereafter constructed to evaluate the cycling performance. The best performing battery half-cell utilized an SPE consisting of SCT and 17 wt% LiTFSI as both binder and electrolyte; a Li vertical bar SPE vertical bar LiFePO4 cell that cycled at 40 degrees C gave a discharge capacity of about 140 mA h g(-1) at C/5 for 100 cycles, which was superior to the other investigated electrolytes. Dynamic mechanical analysis (DMA) showed that the storage modulus E' was about 5 MPa for this electrolyte.

    National Category
    Polymer Chemistry
    Identifiers
    urn:nbn:se:uu:diva-340854 (URN)10.1039/c8ra00377g (DOI)000431814500034 ()
    Funder
    Swedish Energy Agency, 42031-1EU, Horizon 2020, 685716
    Available from: 2018-02-04 Created: 2018-02-04 Last updated: 2022-09-15Bibliographically approved
    4. A Mechanical Robust yet highly Conductive Diblock Copolymer-based Solid Polymer Electrolyte for Room Temperature Structural Battery Applications
    Open this publication in new window or tab >>A Mechanical Robust yet highly Conductive Diblock Copolymer-based Solid Polymer Electrolyte for Room Temperature Structural Battery Applications
    Show others...
    2020 (English)In: ACS Applied Polymer Materials, ISSN 2637-6105, Vol. 2, no 2, p. 939-948Article in journal (Refereed) Published
    Abstract [en]

    In this paper we present a solid polymer electrolyte (SPE) that uniquely combines ionic conductivity and mechanical robustness. This is achieved with a diblock copolymer poly(benzyl methacrylate)-poly(ε-caprolactone-r-trimethylene carbonate). The SPE with 16.7 wt% lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) showed the highest ionic conductivity (9.1×10−6 S cm−1 at 30 °C) and apparent transference number (T+) of 0.64 ± 0.04. Due to the employment of the benzyl methacrylate hard-block, this SPE is mechanically robust with a storage modulus (E') of 0.2 GPa below 40 °C, similar to polystyrene, thus making it a suitable material also for load-bearing constructions. The cell Li|SPE|LiFePO4 is able to cycle reliably at 30 °C for over 300 cycles. The promising mechanical properties, desired for compatibility with Li-metal, together with the fact that BCT is a highly reliable electrolyte material makes this SPE an excellent candidate for next-generation all-solid-state batteries.

    Place, publisher, year, edition, pages
    American Chemical Society (ACS), 2020
    Keywords
    block copolymer, solid polymer electrolyte, lithium-ion battery, structural battery, solid-state battery
    National Category
    Polymer Chemistry
    Identifiers
    urn:nbn:se:uu:diva-340855 (URN)10.1021/acsapm.9b01142 (DOI)000514258700088 ()
    Funder
    Swedish Energy Agency, 40466-1EU, European Research Council, 771777 FUN POLYSTORE
    Available from: 2018-02-04 Created: 2018-02-04 Last updated: 2021-04-22Bibliographically approved
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  • 18.
    Bergfelt, Andreas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Hernández, Guiomar
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Mogensen, Ronnie
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Lacey, Matthew J.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Mindemark, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Brandell, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Bowden, Tim Melander
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    A Mechanical Robust yet highly Conductive Diblock Copolymer-based Solid Polymer Electrolyte for Room Temperature Structural Battery Applications2020In: ACS Applied Polymer Materials, ISSN 2637-6105, Vol. 2, no 2, p. 939-948Article in journal (Refereed)
    Abstract [en]

    In this paper we present a solid polymer electrolyte (SPE) that uniquely combines ionic conductivity and mechanical robustness. This is achieved with a diblock copolymer poly(benzyl methacrylate)-poly(ε-caprolactone-r-trimethylene carbonate). The SPE with 16.7 wt% lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) showed the highest ionic conductivity (9.1×10−6 S cm−1 at 30 °C) and apparent transference number (T+) of 0.64 ± 0.04. Due to the employment of the benzyl methacrylate hard-block, this SPE is mechanically robust with a storage modulus (E') of 0.2 GPa below 40 °C, similar to polystyrene, thus making it a suitable material also for load-bearing constructions. The cell Li|SPE|LiFePO4 is able to cycle reliably at 30 °C for over 300 cycles. The promising mechanical properties, desired for compatibility with Li-metal, together with the fact that BCT is a highly reliable electrolyte material makes this SPE an excellent candidate for next-generation all-solid-state batteries.

    Download full text (pdf)
    fulltext
  • 19.
    Bergfelt, Andreas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Lacey, Matthew J.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Hedman, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Sångeland, Christofer
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Brandell, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Bowden, Tim
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    ε-Caprolactone-based solid polymer electrolytes for lithium-ion batteries: synthesis, electrochemical characterization and mechanical stabilization by block copolymerization2018In: RSC Advances, E-ISSN 2046-2069, Vol. 8, no 30, p. 16716-16725Article in journal (Refereed)
    Abstract [en]

    In this work, three types of polymers based on epsilon-caprolactone have been synthesized: poly(epsilon-caprolactone), polystyrene-poly(epsilon-caprolactone), and polystyrene-poly(epsilon-caprolactone-r-trimethylene carbonate) (SCT), where the polystyrene block was introduced to improve the electrochemical and mechanical performance of the material. Solid polymer electrolytes (SPEs) were produced by blending the polymers with 10-40 wt% lithium bis(trifluoromethane) sulfonimide (LiTFSI). Battery devices were thereafter constructed to evaluate the cycling performance. The best performing battery half-cell utilized an SPE consisting of SCT and 17 wt% LiTFSI as both binder and electrolyte; a Li vertical bar SPE vertical bar LiFePO4 cell that cycled at 40 degrees C gave a discharge capacity of about 140 mA h g(-1) at C/5 for 100 cycles, which was superior to the other investigated electrolytes. Dynamic mechanical analysis (DMA) showed that the storage modulus E' was about 5 MPa for this electrolyte.

    Download full text (pdf)
    fulltext
  • 20.
    Bergfelt, Andreas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Mogensen, Ronnie
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Lacey, Matthew
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Guiomar, Hernández
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Brandell, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Bowden, Tim
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Mechanically Robust and Highly Conductive Di-Block Copolymers as Solid Polymer Electrolytes for Room Temperature Li-ion Batteries2018Conference paper (Other academic)
    Abstract [en]

    Alternative solid polymer electrolytes (SPEs) hosts to the archetype poly(ethylene oxide) are gaining attention thanks to their appealing properties, such as higher cation transport number, thermal stability and electrochemical stability [1]. In addition, high mechanical stability is required in order to integrate easy-to-use materials into flexible or ‘structural’ batteries [2, 3].

     In this work, a solid polymer electrolyte (SPE) featuring high ionic conductivity and mechanical robustness at room temperature is presented. The SPE consists of a di-block copolymer, poly(benzyl methacrylate)-poly(ε-caprolactone-r-trimethylene carbonate) (BCT), mixed with different loadings of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). The highest ionic conductivity achieved for these SPEs was found with 16.7 wt% LiTFSI loading (BCT17), reaching 9.1 x 10-6 S cm-1 at 30 °C. The limited current fraction (F+) for the BCT17 electrolyte was calculated to be 0.64 with the Bruce-Vincent method. Furthermore, dynamic mechanical analysis showed a storage modulus (E’) of 0.2 GPa below 40 °C and 1 MPa above 50 °C. These results indicate that BCT with LiTFSI is a competitive electrolyte, combining high ionic conductivity and modulus at ambient temperatures.

     LiFePO4|BCT17|Li half-cells showed good cycling performance at 60 °C. At 30 °C, where the SPE possessed significantly higher modulus, decent cell performance could still be achieved after several optimization steps. These included incorporating a SPE as binder, and infiltration cast the SPE on the electrode to maximize the contact between both components, thereby improving the interfacial contact and decreasing the cell resistance and overpotential when cycling the battery device.

     References

    [1] J. Mindemark, M.J. Lacey, T. Bowden, D. Brandell. Prog Polym Sci, (2018). DOI: 10.1016/j.progpolymsci.2017.12.004.

    [2] J.F. Snyder, R.H. Carter, E.D. Wetzel. Chem Mater, 19 (2007) 3793-801.

    [3] W.S. Young, W.F. Kuan, Thomas H. Epps. J Polym Sci, Part B: Polym Phys, 52 (2014) 1-16.

  • 21.
    Bergfelt, Andreas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Rubatat, Laurent
    CNRS/UNIV Pau & Pays Adour, Institut des Sciences Analytiques et de Physico-Chimie pour l´ Environnement et les Materiaux, Pau, France.
    Brandell, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Bowden, Tim
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Poly(benzyl methacrylate)-Poly[(oligo ethylene glycol) methyl ether methacrylate] Triblock-Copolymers as Solid Electrolyte for Lithium Batteries2018In: Solid State Ionics, ISSN 0167-2738, E-ISSN 1872-7689, Vol. 321, p. 55-61Article in journal (Refereed)
    Abstract [en]

    A triblock copolymer of benzyl methacrylate and oligo(ethylene glycol) methyl ether methacrylate was polymerized to form the general structure PBnMA-POEGMA-PBnMA, using atom transfer radical polymerization (ATRP). The block copolymer (BCP) was blended with lithium bis(trifluoro methylsulfonate) (LiTFSI) to form solid polymer electrolytes (SPEs). AC impedance spectroscopy was used to study the ionic conductivity of the SPE series in the temperature interval 30 °C to 90 °C. Small-angle X-ray scattering (SAXS) was used to study the morphology of the electrolytes in the temperature interval 30 °C to 150 °C. By using benzyl methacrylate as a mechanical block it was possible to tune the microphase separation by the addition of LiTFSI, as proven by SAXS. By doing so the ionic conductivity increased to values higher than ones measured on a methyl methacrylate triblock copolymer-based electrolyte in the mixed state, which was investigated in an earlier paper by our group. A Li|SPE|LiFePO4 half-cell was constructed and cycled at 60 °C. The cell produced a discharge capacity of about 100 mAh g−1 of LiFePO4 at C/10, and the half-cell cycled for more than 140 cycles.

    Download full text (pdf)
    fulltext
  • 22.
    Bergfelt, Andreas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Rubatat, Laurent
    Univ Pau & Pays Adour, CNRS, Inst Sci Analyt & Physicochim Environm & Mat, UMR5254, F-64000 Pau, France.
    Mogensen, Ronnie
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Brandell, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Bowden, Tim
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    d8-poly(methyl methacrylate)-poly[(oligo ethylene glycol) methyl ether methacrylate] tri-block-copolymer electrolytes: Morphology, conductivity and battery performance2017In: Polymer, ISSN 0032-3861, E-ISSN 1873-2291, Vol. 131, p. 234-242Article in journal (Refereed)
    Abstract [en]

    A series of deuterated tri-block copolymers with the general structure d(8)-PMMA-POEGMA-d(8)-PMMA, with variation in d(8)-PMMA chain length, were synthesized using sequential controlled radical polymerization (ATRP). Solid polymer electrolytes (SPEs) were produced by blending tri-block copolymers and lithium bis(trifluoro methylsulfonate) (LiTFSI). Small-angle neutron scattering (SANS) was used to study the bulk morphology of the deuterated tri-block copolymer electrolyte series at 25 degrees C, 60 degrees C and 95 degrees C. The lack of a second T-g in DSC analysis together with modelling with the random phase approximation model (RPA) confirmed that the electrolytes are in the mixed state, with negative Flory-Huggins interaction parameters. AC impedance spectroscopy was used to study the ionic conductivity of the SPE series in the temperature interval 30 degrees C-90 degrees C, and a battery device was constructed to evaluate a 25 wt% d(8)-PMMA electrolyte. The Li | SPE | LiFePO4 cell cycled at 60 degrees C, giving a discharge capacity of 120 mAh g(-1), while cyclic voltammetry showed that the SPE was stable at 60 degrees C.

  • 23.
    Bergman, Martin
    et al.
    Chalmers, Dept Appl Phys, SE-41296 Gothenburg, Sweden..
    Bergfelt, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Sun, Bing
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Bowden, Tim
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Brandell, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry. Uppsala Univ, Dept Chem, Angstrom Lab, SE-75121 Uppsala, Sweden..
    Johansson, Patrik
    Chalmers, Dept Appl Phys, SE-41296 Gothenburg, Sweden..
    Graft copolymer electrolytes for high temperature Li-battery applications, using poly(methyl methacrylate) grafted poly(ethylene glycol)methyl ether methacrylate and lithium bis(trifluoromethanesulfonimide)2015In: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 175, p. 96-103Article in journal (Refereed)
    Abstract [en]

    For successful hybridization of heavy vehicles, high temperature batteries might be the solution. Here, high temperature solid polymer electrolytes (SPE's) based on different ratios of poly(methyl methacrylate) (PMMA) and poly(ethylene glycol) methyl ether methacrylate (PEGMA), with LiTFSI salt (at a fixed ether oxygen (EO):Li ratio of 20:1) have been prepared and investigated. The copolymers comprise PMMA backbones with grafted PEGMA side-chains containing 9 EO units. The SPE systems were characterized using Raman spectroscopy, broadband dielectric spectroscopy, differential scanning calorimetry, thermal gravimetric analysis, and electrochemical cycling in prototype cells, with a particular focus on the 83 wt% PEGMA system. The electrolytes have good thermal stabilities and dissociate the LiTFSI salt easily, while at the same time maintaining low glass transition temperatures (T-g's). Depending on the polymeric structure, ionic conductivities >1 mS cm(-1) at 110 degrees C are detected, thus providing ion transport properties for a broad range of electrochemical applications. Prototype Li vertical bar polymer electrolyte vertical bar LiFePO4 cells utilizing the SPE at 60 degrees C showed surprisingly low capacities (<20 mA h g(-1) LiFePO4), which could be due to poor electrode/electrolyte contacts.

  • 24.
    Bermejo, Daniel
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Kadekar, Sandeep
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Tavares da Costa, Marcus Vinicius
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Podiyan, Oommen
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Gamstedt, E. Kristofer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Varghese, Oommen P.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    First Aldol-Crosslinked Hyaluronic Acid Hydrogel: Fast and Hydrolytically Stable Gel with Tissue Adhesive PropertiesIn: Chemical Sciences Journal, ISSN 2150-3494Article in journal (Refereed)
    Abstract [en]

    Currently, there are limited approaches to tailor 3D scaffolds crosslinked with a stable covalent C-C bond that does not require any catalysts or initiators. We present here the first hydrogels employing aldol condensation chemistry that exhibit exceptional physicochemical properties. We investigated the aldol-crosslinking chemistry using two types of aldehyde-modified hyaluronic acid (HA) derivatives, namely; an enolizable HA-aldehyde (HA-Eal) and a non-enolizable HA-aldehyde (HA-Nal). Hydrogels formed using HA-Eal demonstrate inferior crosslinking efficiency (due to intramolecular loop formation), when compared with hydrogels formed by mixing HA-Eal and HA-NaI leading to a cross-aldol product. The change in mechanical properties as a result of crosslinking at different pH is determined using rheological measurements and is interpreted in terms of molecular weight between cross-links (Mc). The novel HA cross-aldol hydrogels demonstrate excellent hydrolytic stability and favorable mechanical properties but allow hyaluronidase mediated enzymatic degradation. Interestingly, residual aldehyde functionality within the aldol product leads to adhesion to tissue as demonstrated by bonding two bone tissues. The aldehyde functionality also permits facile post-synthetic modifications with nucleophilic reagents such as Alexa FluorTM 488. Finally, we demonstrate that the novel hydrogel is biocompatible with encapsulated stem cells that show a linear rate of expansion in our 3–6 days of study.

  • 25.
    Bermejo-Velasco, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Insights into Covalent Chemistry for the Developmen­t of Biomaterials2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Covalent cross-linking chemistry is currently exploited in the preparation of biomaterial for biomedical applications. Choice of these chemistries for the preparation of biomaterials and bioconjugates strongly influences the biological output of these materials. Therefore, this thesis aims to develop novel bioconjugation strategies understanding their advantages and drawbacks. Our results provide new insight to adapt these chemical transformations for a specific application.

    The first part of this thesis points out the relevance of tuning different properties of biomaterials with specific emphasis on the development of hyaluronic acid (HA) hydrogels. The second part of the thesis describes how different chemical transformations including hydrazone formation (Paper I), thiazolidine formation (Paper II), cross-aldol addition reaction (Paper III) and disulfide formation (Paper IV) dictate material properties.

    This thesis explores both basic organic reaction mechanism and application of these reactions to influence material characteristics. The detailed study of the reaction conditions, kinetics, and stability of the products will help to understand the mechanical properties, hydrolytic stability, and degradability of the materials described here.

    Additionally, we performed degradation studies of gadolinium labeled HA hydrogels using magnetic resonance imaging. Furthermore, we also explored post-synthetic modification of hydrogels to link model fluorescent moieties as well as explored the tissue adhesive properties using Schiff-base formation.

    In summary, this thesis presents a selection of different covalent chemistries for the design of advanced biomaterials. The advantages and disadvantages of these chemistries are rigorously investigated. We believe, such an investigation provides a better understanding of the bioconjugation strategies for the preparation of biomaterials with potential clinical translation.

    List of papers
    1. Injectable hyaluronic acid hydrogels with the capacity for magnetic resonance imaging
    Open this publication in new window or tab >>Injectable hyaluronic acid hydrogels with the capacity for magnetic resonance imaging
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    2018 (English)In: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 197, p. 641-648Article in journal (Refereed) Published
    Abstract [en]

    Monitoring hydrogel degradation in real time using noninvasive imaging techniques is of great interest for designing a scaffold in tissue engineering. We report the preparation of gadolinium (Gd)-labeled and injectable hyaluronic acid (HA) hydrogels that can be visualized using T-1- and T-2-weighted magnetic resonance imaging (MRI). An HA derivative functionalized with thiol and hydrazide was labeled using a diethylenetriaminepentaacetate complex modified with "clickable" dithiopyridyl functionalities (degree of modification was 3.77% with respect to HA repeat units). The HA derivative modified with cross-linkable groups and Gd complex exhibited relaxivities r(1) = 3.78 mM(-1)s(-1) and r(2) = 56.3 mM(-1)s(-1). A hydrazone hydrogel network was obtained by mixing Gd-labeled HA-hydrazide and HA-aldehyde derivatives. Enzymatic hydrogel degradation could be followed using MRI because the MR images showed great correlation with the hydrogel mass loss. Ex vivo MRI of injected Gd-labeled hydrogels demonstrated that they show a significant contrast difference (SNRcoronal = 456; SNRaxial = 459) from the surrounding tissues. These results indicate that our Gd-labeled HA hydrogel has great potential as an injectable biocompatible hydrogel that can be used for longitudinal tracking in vivo using MRI.

    Place, publisher, year, edition, pages
    Elsevier, 2018
    Keywords
    Gadolinium complex, Hyaluronic acid, Injectable hydrogels, Magnetic resonance imaging, Biodegradation
    National Category
    Polymer Chemistry
    Identifiers
    urn:nbn:se:uu:diva-361020 (URN)10.1016/j.carbpol.2018.06.028 (DOI)000438466500070 ()30007657 (PubMedID)
    Available from: 2018-09-20 Created: 2018-09-20 Last updated: 2022-10-24Bibliographically approved
    2. Thiazolidine chemistry revisited: a fast, efficient and stable click-type reaction at physiological pH
    Open this publication in new window or tab >>Thiazolidine chemistry revisited: a fast, efficient and stable click-type reaction at physiological pH
    Show others...
    2018 (English)In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 54, no 88, p. 12507-12510Article in journal (Refereed) Published
    Abstract [en]

    We describe the fast reaction kinetics between 1,2-aminothiols and aldehydes. Under physiological conditions such a click-type reaction afforded a thiazolidine product that remains stable and did not require any catalyst. This type of bioorthogonal reaction offers enormous potential for the coupling of biomolecules in an efficient and biocompatible manner.

    National Category
    Polymer Chemistry
    Identifiers
    urn:nbn:se:uu:diva-364896 (URN)10.1039/c8cc05405c (DOI)000448947000019 ()30345438 (PubMedID)
    Available from: 2018-11-06 Created: 2018-11-06 Last updated: 2019-06-26Bibliographically approved
    3. First Aldol-Crosslinked Hyaluronic Acid Hydrogel: Fast and Hydrolytically Stable Gel with Tissue Adhesive Properties
    Open this publication in new window or tab >>First Aldol-Crosslinked Hyaluronic Acid Hydrogel: Fast and Hydrolytically Stable Gel with Tissue Adhesive Properties
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    (English)In: Chemical Sciences Journal, ISSN 2150-3494Article in journal (Refereed) Submitted
    Abstract [en]

    Currently, there are limited approaches to tailor 3D scaffolds crosslinked with a stable covalent C-C bond that does not require any catalysts or initiators. We present here the first hydrogels employing aldol condensation chemistry that exhibit exceptional physicochemical properties. We investigated the aldol-crosslinking chemistry using two types of aldehyde-modified hyaluronic acid (HA) derivatives, namely; an enolizable HA-aldehyde (HA-Eal) and a non-enolizable HA-aldehyde (HA-Nal). Hydrogels formed using HA-Eal demonstrate inferior crosslinking efficiency (due to intramolecular loop formation), when compared with hydrogels formed by mixing HA-Eal and HA-NaI leading to a cross-aldol product. The change in mechanical properties as a result of crosslinking at different pH is determined using rheological measurements and is interpreted in terms of molecular weight between cross-links (Mc). The novel HA cross-aldol hydrogels demonstrate excellent hydrolytic stability and favorable mechanical properties but allow hyaluronidase mediated enzymatic degradation. Interestingly, residual aldehyde functionality within the aldol product leads to adhesion to tissue as demonstrated by bonding two bone tissues. The aldehyde functionality also permits facile post-synthetic modifications with nucleophilic reagents such as Alexa FluorTM 488. Finally, we demonstrate that the novel hydrogel is biocompatible with encapsulated stem cells that show a linear rate of expansion in our 3–6 days of study.

    Keywords
    hyaluronic acid, aldol chemisty, stable hydrogels, tissue adhesive
    National Category
    Materials Chemistry
    Research subject
    Chemistry with specialization in Materials Chemistry
    Identifiers
    urn:nbn:se:uu:diva-374999 (URN)
    Available from: 2019-01-24 Created: 2019-01-24 Last updated: 2019-01-24
    4. Modulating thiol pKa promotes disulfide formation at physiological pH: An elegant strategy to design disulfide cross-linked hyaluronic acid hydrogels
    Open this publication in new window or tab >>Modulating thiol pKa promotes disulfide formation at physiological pH: An elegant strategy to design disulfide cross-linked hyaluronic acid hydrogels
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    2019 (English)In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 20, no 3, p. 1412-1420Article in journal (Refereed) Published
    Abstract [en]

    The disulfide bond plays a crucial role in protein biology and has been exploited by scientists to develop antibody-drug conjugates, sensors and for the immobilization other biomolecules to materials surfaces. In spite of its versatile use, the disulfide chemistry suffers from some inevitable limitations such as the need for basic conditions (pH > 8.5), strong oxidants and long reaction times. We demonstrate here that thiol-substrates containing electron-withdrawing groups at the β-position influence the deprotonation of the thiol group, which is the key reaction intermediate in the formation of disulfide bonds. Evaluation of reaction kinetics using small molecule substrate such as L-cysteine indicated disulfide formation at a 2.8-fold higher (k1 = 5.04 x 10-4 min-1) reaction rate as compared to the conventional thiol substrate, namely 3-mercaptopropionic acid (k1 = 1.80 x 10-4 min-1) at physiological pH (pH 7.4). Interestingly, the same effect could not be observed when N-acetyl-L-cysteine substrate (k1 = 0.51 x 10-4 min-1) was used. We further grafted such thiol-containing molecules (cysteine, N-acetyl-cysteine, and 3-mercaptopropionic acid) to a biopolymer namely hyaluronic acid (HA) and determined the pKa value of different thiol groups by spectrophotometric analysis. The electron-withdrawing group at the β-position reduced the pKa of the thiol group to 7.0 for HA-cysteine (HA-Cys); 7.4 for N-acetyl cysteine (HA-ActCys) and 8.1 for HA-thiol (HA-SH) derivatives respectively. These experiments further confirmed that the concentration of thiolate (R-S-) ions could be increased with the presence of electron-withdrawing groups, which could facilitate disulfide cross-linked hydrogel formation at physiological pH. Indeed, HA grafted with cysteine or N-acetyl groups formed hydrogels within 3.5 minutes or 10 hours, respectively at pH 7.4. After completion of crosslinking reaction both gels demonstrated a storage modulus G’ ≈3300–3500 Pa, indicating comparable levels of crosslinking. The HA-SH gel, on the other hand, did not form any gel at pH 7.4 even after 24 h. Finally, we demonstrated that the newly prepared hydrogels exhibited excellent hydrolytic stability but can be degraded by cell-directed processes (enzymatic and reductive degradation). We believe our study provides a valuable insight on the factors governing the disulfide formation and our results are useful to develop strategies that would facilitate generation of stable thiol functionalized biomolecules or promote fast thiol oxidation according to the biomedical needs.

    National Category
    Materials Chemistry
    Research subject
    Chemistry with specialization in Materials Chemistry
    Identifiers
    urn:nbn:se:uu:diva-375001 (URN)10.1021/acs.biomac.8b01830 (DOI)000461270500028 ()30726668 (PubMedID)
    Funder
    Swedish Foundation for Strategic Research , 139400127EU, FP7, Seventh Framework Programme, 607868Swedish Foundation for Strategic Research , 139400126
    Available from: 2019-01-24 Created: 2019-01-24 Last updated: 2019-04-11Bibliographically approved
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  • 26.
    Bermejo-Velasco, Daniel
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Azémar, Alice
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Oommen, Oommen P.
    Bioengineering and Nanomedicine Lab, Faculty of Medicine and Health Technologies and BioMediTech Institute, Tampere University, Korkeakoulunkatu 3, Tampere 33720, Finland.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Varghese, Oommen P.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Modulating thiol pKa promotes disulfide formation at physiological pH: An elegant strategy to design disulfide cross-linked hyaluronic acid hydrogels2019In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 20, no 3, p. 1412-1420Article in journal (Refereed)
    Abstract [en]

    The disulfide bond plays a crucial role in protein biology and has been exploited by scientists to develop antibody-drug conjugates, sensors and for the immobilization other biomolecules to materials surfaces. In spite of its versatile use, the disulfide chemistry suffers from some inevitable limitations such as the need for basic conditions (pH > 8.5), strong oxidants and long reaction times. We demonstrate here that thiol-substrates containing electron-withdrawing groups at the β-position influence the deprotonation of the thiol group, which is the key reaction intermediate in the formation of disulfide bonds. Evaluation of reaction kinetics using small molecule substrate such as L-cysteine indicated disulfide formation at a 2.8-fold higher (k1 = 5.04 x 10-4 min-1) reaction rate as compared to the conventional thiol substrate, namely 3-mercaptopropionic acid (k1 = 1.80 x 10-4 min-1) at physiological pH (pH 7.4). Interestingly, the same effect could not be observed when N-acetyl-L-cysteine substrate (k1 = 0.51 x 10-4 min-1) was used. We further grafted such thiol-containing molecules (cysteine, N-acetyl-cysteine, and 3-mercaptopropionic acid) to a biopolymer namely hyaluronic acid (HA) and determined the pKa value of different thiol groups by spectrophotometric analysis. The electron-withdrawing group at the β-position reduced the pKa of the thiol group to 7.0 for HA-cysteine (HA-Cys); 7.4 for N-acetyl cysteine (HA-ActCys) and 8.1 for HA-thiol (HA-SH) derivatives respectively. These experiments further confirmed that the concentration of thiolate (R-S-) ions could be increased with the presence of electron-withdrawing groups, which could facilitate disulfide cross-linked hydrogel formation at physiological pH. Indeed, HA grafted with cysteine or N-acetyl groups formed hydrogels within 3.5 minutes or 10 hours, respectively at pH 7.4. After completion of crosslinking reaction both gels demonstrated a storage modulus G’ ≈3300–3500 Pa, indicating comparable levels of crosslinking. The HA-SH gel, on the other hand, did not form any gel at pH 7.4 even after 24 h. Finally, we demonstrated that the newly prepared hydrogels exhibited excellent hydrolytic stability but can be degraded by cell-directed processes (enzymatic and reductive degradation). We believe our study provides a valuable insight on the factors governing the disulfide formation and our results are useful to develop strategies that would facilitate generation of stable thiol functionalized biomolecules or promote fast thiol oxidation according to the biomedical needs.

  • 27.
    Bermejo-Velasco, Daniel
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Dou, Weiqiang
    Radboud Univ Nijmegen, Med Ctr, Dept Radiol & Nucl Med, Nijmegen, Netherlands.
    Heerschap, Arend
    Radboud Univ Nijmegen, Med Ctr, Dept Radiol & Nucl Med, Nijmegen, Netherlands.
    Ossipov, Dmitri A.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Injectable hyaluronic acid hydrogels with the capacity for magnetic resonance imaging2018In: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 197, p. 641-648Article in journal (Refereed)
    Abstract [en]

    Monitoring hydrogel degradation in real time using noninvasive imaging techniques is of great interest for designing a scaffold in tissue engineering. We report the preparation of gadolinium (Gd)-labeled and injectable hyaluronic acid (HA) hydrogels that can be visualized using T-1- and T-2-weighted magnetic resonance imaging (MRI). An HA derivative functionalized with thiol and hydrazide was labeled using a diethylenetriaminepentaacetate complex modified with "clickable" dithiopyridyl functionalities (degree of modification was 3.77% with respect to HA repeat units). The HA derivative modified with cross-linkable groups and Gd complex exhibited relaxivities r(1) = 3.78 mM(-1)s(-1) and r(2) = 56.3 mM(-1)s(-1). A hydrazone hydrogel network was obtained by mixing Gd-labeled HA-hydrazide and HA-aldehyde derivatives. Enzymatic hydrogel degradation could be followed using MRI because the MR images showed great correlation with the hydrogel mass loss. Ex vivo MRI of injected Gd-labeled hydrogels demonstrated that they show a significant contrast difference (SNRcoronal = 456; SNRaxial = 459) from the surrounding tissues. These results indicate that our Gd-labeled HA hydrogel has great potential as an injectable biocompatible hydrogel that can be used for longitudinal tracking in vivo using MRI.

  • 28.
    Bermejo-Velasco, Daniel
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Kadekar, Sandeep
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Tavares da Costa, Marcus Vinicius
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Oommen, Oommen P.
    Tampere Univ, Bioengn & Nanomed Lab, Fac Med & Hlth Technol, Korkeakoulunkatu 3, Tampere 33720, Finland;Tampere Univ, BioMediTech Inst, Korkeakoulunkatu 3, Tampere 33720, Finland.
    Gamstedt, E. Kristofer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Varghese, Oommen P.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    First Aldol Cross-Linked Hyaluronic Acid Hydrogel: Fast and Hydrolytically Stable Hydrogel with Tissue Adhesive Properties2019In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 11, no 41, p. 38232-38239Article in journal (Refereed)
    Abstract [en]

    Currently, there are limited approaches to tailor 3D scaffolds cross-linked with a stable covalent C-C bond that does not require any catalysts or initiators. We present here the first hydrogels employing aldol condensation chemistry that exhibit exceptional physicochemical properties. We investigated the aldol-cross-linking chemistry using two types of aldehyde-modified hyaluronic acid (HA) derivatives, namely, an enolizable HA-aldehyde (HA-EaI) and a non-enolizable HA-aldehyde (HA-NaI). Hydrogels formed using HA-EaI demonstrate inferior cross linking efficiency (due to intramolecular loop formation), when compared with hydrogels formed by mixing HA-EaI and HA-NaI leading to a cross-aldol product. The change in mechanical properties as a result of cross-linking at different pH values is determined using rheological measurements and is interpreted in terms of molecular weight between cross-links (Me). The novel HA cross-aldol hydrogel demonstrate excellent hydrolytic stability and favorable mechanical properties but allow hyaluronidase-mediated enzymatic degradation. Interestingly, residual aldehyde functionality within the aldol product rendered the tissue adhesive properties by bonding two bone tissues. The aldehyde functionality also facilitated facile post-synthetic modifications with nucleophilic reagents. Finally, we demonstrate that the novel hydrogel is biocompatible with encapsulated stem cells that show a linear rate of expansion in our 3-6 days of study.

  • 29.
    Bermejo-Velasco, Daniel
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Nawale, Ganesh N.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Oommen, Oommen P.
    Bioengineering and Nanomedicine Lab, Faculty of Biomedical Sciences and Engineering, Tampere University of Technology, and BioMediTech Institute, 33720, Tampere, Finland.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Varghese, Oommen P.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Thiazolidine chemistry revisited: a fast, efficient and stable click-type reaction at physiological pH2018In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 54, no 88, p. 12507-12510Article in journal (Refereed)
    Abstract [en]

    We describe the fast reaction kinetics between 1,2-aminothiols and aldehydes. Under physiological conditions such a click-type reaction afforded a thiazolidine product that remains stable and did not require any catalyst. This type of bioorthogonal reaction offers enormous potential for the coupling of biomolecules in an efficient and biocompatible manner.

    Download full text (pdf)
    fulltext
  • 30.
    Berts, Ida
    et al.
    Uppsala University, Science for Life Laboratory, SciLifeLab. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Fragneto, Giovanna
    Institut Laue-Langevin.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Rennie, Adrian R.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Physics.
    Tuning the density profile of surface-grafted hyaluronan and the effect of counter-ions2013In: European Physical Journal E, ISSN 1292-8941, Vol. 36, no 7, p. 70-Article in journal (Refereed)
    Abstract [en]

    The present paper investigates the structure and composition of grafted sodium hyaluronanat a solid-liquid interface using neutron reflection. The solvated polymer at the surface could be described with a density profile that decays exponentially towards the bulk solution. The density profileof the polymer varied depending on the deposition protocol. A single-stage deposition resulted in denser polymer layers, while layers created with a two-stage deposition process were more diffuse and had an overall lower density. Despite the diffuse density profile, two-stage deposition leads to a highersurface excess. Addition of calcium ions causes a strong collapse of the sodium hyaluronan chains, increasing the polymer density near the surface. This effect is more pronounced on the sample prepared by two-stage deposition due to the initial less dense profile. This study provides an understanding at a molecular level of how surface functionalization alters the structure and howsurface layers respond to changes in calcium ions in the solvent.

  • 31.
    Berts, Ida
    et al.
    Uppsala University, Science for Life Laboratory, SciLifeLab. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Inst Laue Langevin, 71 Ave Martyrs,CS 20156, F-38042 Grenoble, France..
    Fragneto, Giovanna
    Inst Laue Langevin, 71 Ave Martyrs,CS 20156, F-38042 Grenoble, France..
    Porcar, Lionel
    Inst Laue Langevin, 71 Ave Martyrs,CS 20156, F-38042 Grenoble, France..
    Hellsing, Maja S.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Physics. Uppsala Univ, Ctr Neutron Scattering, Box 516, S-75120 Uppsala, Sweden..
    Rennie, Adrian R.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Physics. Uppsala Univ, Ctr Neutron Scattering, Box 516, S-75120 Uppsala, Sweden..
    Controlling adsorption of albumin with hyaluronan on silica surfaces and sulfonated latex particles2017In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 504, p. 315-324Article in journal (Refereed)
    Abstract [en]

    Polysaccharides are known to modify binding of proteins at interfaces and this paper describes studies of these interactions and how they are modified by pH. Specifically, the adsorption of human serum albumin on to polystyrene latex and to silica is described, focusing on how this is affected by hyaluronan. Experiments were designed to test how such binding might be modified under relevant physiological conditions. Changes in adsorption of albumin alone and the co-adsorption of albumin and hyaluronan are driven by electrostatic interactions. Multilayer binding is found to be regulated by the pH of the solution and the molecular mass and concentration of hyaluronan. Highest adsorption was observed at pH below 4.8 and for low molecular mass hyaluronan (<= 150 kDa) at concentrations above 2 mg ml(-1). On silica with grafted hyaluronan, albumin absorption is reversed by changes in solvent pH due to their strong electrostatic attraction. Albumin physisorbed on silica surfaces is also rinsed away with dilute hyaluronan solution at pH 4.8. The results demonstrate that the protein adsorption can be controlled both by changes of pH and by interaction with other biological macromolecules.

  • 32.
    Berts, Ida
    et al.
    Uppsala University, Science for Life Laboratory, SciLifeLab. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Gerelli, Yuri
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Rennie, Adrian R.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Physics.
    Structure of polymer and particle aggregates in hydrogel composites2013In: Journal of Polymer Science Part B: Polymer Physics, ISSN 0887-6266, E-ISSN 1099-0488, Vol. 51, no 6, p. 421-429Article in journal (Refereed)
    Abstract [en]

    Knowledge of the structure of a biomaterial is usually vital to control its function. This article provides a structural characterization of a hyaluronan scaffold that has demonstrated good biocompatibility and is used to induce bone regeneration. Hyaluronan hydrogels are appealing materials that can function as a matrix to incorporate both organic and inorganic substances to enhance tissue growth. Because of the intrinsic properties of this swollen matrix, one needs a very sensitive technique that can be applied in situ to determine the organization of the polymers in a gel. Small-angle neutron scattering is used to determine the characteristics of the inhomogeneous structure of the hydrogel both with and without added particles. The results are interpreted using models of structure with two length scales that are beyond the traditional picture of homogeneous gels. The observed structure and the dimensions can explain the previously reported rheological properties of gels containing different amount of polymers. Hydroxyapatite nanoparticles added to the gel are frozen in the gel matrix. We are able to determine the distribution and shape of these particles as they aggregate around the polymer chains. We have also concluded, in this case, that the particle structure is concentration independent. Information about the nanostructure for an applicable biomaterial guides the formulation, preparation, and use that should lead to further understanding of its exploitation.

  • 33.
    Billström, Gry Hulsart
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Orthopaedics.
    Piskounova, Sonya
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Gedda, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Biomedical Radiation Sciences.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Bowden, Tim
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Larsson, Sune
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Orthopaedics.
    Improved bone formation by altering surface area of hyaluronan-based hydrogel carrier for bone morphogenetic protein-22012In: Bone, ISSN 8756-3282, E-ISSN 1873-2763, Vol. 50, p. S114-S114Article in journal (Other academic)
  • 34.
    Calitz, Carlemi
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Pavlovic, Natasa
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Rosenquist, Jenny
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Zagami, Claudia
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Samanta, Ayan
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Heindryckx, Femke
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    A Biomimetic Model for Liver Cancer to Study Tumor-Stroma Interactions in a 3D Environment with Tunable Bio-Physical Properties2020In: Journal of Visualized Experiments, E-ISSN 1940-087X, no 162, article id e61606Article in journal (Refereed)
    Abstract [en]

    Hepatocellular carcinoma (HCC) is a primary liver tumor developing in the wake of chronic liver disease. Chronic liver disease and inflammation leads to a fibrotic environment actively supporting and driving hepatocarcinogenesis. Insight into hepatocarcinogenesis in terms of the interplay between the tumor stroma microenvironment and tumor cells is thus of considerable importance. Three-dimensional (3D) cell culture models are proposed as the missing link between current in vitro 2D cell culture models and in vivo animal models. Our aim was to design a novel 3D biomimetic HCC model with accompanying fibrotic stromal compartment and vasculature. Physiologically relevant hydrogels such as collagen and fibrinogen were incorporated to mimic the bio-physical properties of the tumor ECM. In this model LX2 and HepG2 cells embedded in a hydrogel matrix were seeded onto the inverted transmembrane insert. HUVEC cells were then seeded onto the opposite side of the membrane. Three formulations consisting of ECM-hydrogels embedded with cells were prepared and the bio-physical properties were determined by rheology. Cell viability was determined by a cell viability assay over 21 days. The effect of the chemotherapeutic drug doxorubicin was evaluated in both 2D co-culture and our 3D model for a period of 72h. Rheology results show that bio-physical properties of a fibrotic, cirrhotic and HCC liver can be successfully mimicked. Overall, results indicate that this 3D model is more representative of the in vivo situation compared to traditional 2D cultures. Our 3D tumor model showed a decreased response to chemotherapeutics, mimicking drug resistance typically seen in HCC patients.

  • 35.
    Cantoni, Federico
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Johansson, Sofia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Pohlit, Hannah
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Porras, Ana Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Samanta, Ayan
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Tenje, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    2D and 3D patterning of biological hydrogels for organ-on-chip applications2018Conference paper (Other academic)
  • 36.
    Cantoni, Federico
    et al.
    Uppsala University, Science for Life Laboratory, SciLifeLab. Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering.
    Samanta, Ayan
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Tenje, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Methacryl modified gelatin hydrogels for co-culture of cells to mimic blood-brain barrier2018Conference paper (Other academic)
  • 37.
    Carter, Sarah-Sophia
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Microsystems Technology.
    Atif, Abdul Raouf
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Microsystems Technology.
    Kadekar, Sandeep
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Lanekoff, Ingela
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - BMC, Analytical Chemistry.
    Engqvist, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences. Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Applied Material Science.
    Varghese, Oommen P.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Tenje, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Mestres, Gemma
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    PDMS leaching and its implications for on-chip studies focusing on bone regeneration applications2020In: Organs-on-a-Chip, ISSN 2666-1020, Vol. 2, article id 100004Article in journal (Refereed)
    Abstract [en]

    Polydimethylsiloxane (PDMS) is among the most widely used materials for organ-on-chip systems. Despite itsmultiple beneficial characteristics from an engineering point of view, there is a concern about the effect of PDMSon the cells cultured in such devices. The aim of this study was to enhance the understanding of the effect of PDMSon cellular behavior in a context relevant for on-chip studies. The focus was put on an indirect effect of PDMS,namely leaching of uncrosslinked oligomers, particularly for bone regeneration applications. PDMS-based chipswere prepared and analyzed for the potential release of PDMS oligomers within the microfluidic channel whenkept at different flow rates. Leaching of uncrosslinked oligomers from PDMS was quantified as silicon concen-tration by inductively coupled plasma - optical emission spectrometry and further confirmed by mass spec-trometry. Subsequently, PDMS-leached media, with a silicon concentration matching the on-chip experiment,were prepared to study cell proliferation and osteogenic differentiation of MC3T3-E1 pre-osteoblasts and humanmesenchymal stem cells. The silicon concentration initially detected in the media was inversely proportional tothe tested flow rates and decreased to control levels within 52 h. In addition, by curing the material overnightinstead of 2 h, regardless of the curing temperature (65 and 80 C), a large reduction in silicon concentration wasfound, indicating the importance of the PDMS curing parameters. Furthermore, it was shown that PDMS oligo-mers enhanced the differentiation of MC3T3-E1 pre-osteoblasts, this being a cell type dependent effect as nochanges in cell differentiation were observed for human mesenchymal stem cells. Overall, this study illustrates theimportance of optimization steps when using PDMS devices for biological studies, in particular PDMS curingconditions and extensive washing steps prior to an experiment.

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  • 38.
    Castejon, Natalia
    et al.
    Univ Pau & Pays Adour, IPREM, UPPA E2S, CNRS, F-64600 Anglet, France.;Univ Pau & Pays Adour, MANTA Marine Mat Res Grp, UPPA E2S, F-64600 Anglet, France.;Univ Vienna, Dept Food Chem & Toxicol, A-1090 Vienna, Austria..
    Parailloux, Maroussia
    Univ Pau & Pays Adour, IPREM, UPPA E2S, CNRS, F-64600 Anglet, France..
    Izdebska, Aleksandra
    Univ Pau & Pays Adour, IPREM, UPPA E2S, CNRS, F-64600 Anglet, France..
    Lobinski, Ryszard
    Univ Pau & Pays Adour, IPREM, UPPA E2S, CNRS, F-64600 Anglet, France..
    Fernandes, Susana C. M.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Univ Pau & Pays Adour, IPREM, UPPA E2S, CNRS, F-64600 Anglet, France.;Univ Pau & Pays Adour, MANTA Marine Mat Res Grp, UPPA E2S, F-64600 Anglet, France..
    Valorization of the Red Algae Gelidium sesquipedale by Extracting a Broad Spectrum of Minor Compounds Using Green Approaches2021In: Marine Drugs, ISSN 1660-3397, E-ISSN 1660-3397, Vol. 19, no 10, article id 574Article in journal (Refereed)
    Abstract [en]

    Until now, the red algae Gelidium sesquipedale has been primarily exploited for agar production, leaving an undervalued biomass. In this work, the use of eco-friendly approaches employing ultrasound-assisted extraction (UAE) and green solvents was investigated to valorize the algal minor compounds. The green methods used herein showed an attractive alternative to efficiently extract a broad spectrum of bioactive compounds in short extraction times (15 to 30 min vs. 8 h of the conventional method). Using the best UAE conditions, red seaweed extracts were characterized in terms of total phenolics (189.3 & PLUSMN; 11.7 mg GAE/100 g dw), flavonoids (310.7 & PLUSMN; 9.7 mg QE/100 g dw), mycosporine-like amino acids (MAAs) (sigma MAAs = 1271 mg/100 g dw), and phycobiliproteins (72.4 & PLUSMN; 0.5 mg/100 g dw). Additionally, produced algal extracts exhibited interesting antioxidant and anti-enzymatic activities for potential applications in medical and/or cosmetic products. Thus, this study provides the basis to reach a superior valorization of algal biomass by using alternative methods to extract biologically active compounds following eco-friendly approaches. Moreover, the strategies developed not only open new possibilities for the commercial use of Gelidium sesquipedale, but also for the valorization of different algae species since the techniques established can be easily adapted.

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  • 39.
    Chen, Song
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Shi, Liyang
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Hunan Univ, Coll Biol, Changsha 410082, Hunan, Peoples R China.
    Luo, Jun
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Engqvist, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Novel Fast-Setting Mineral Trioxide Aggregate: Its Formulation, Chemical-Physical Properties, and Cytocompatibility2018In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 10, no 24, p. 20334-20341Article in journal (Refereed)
    Abstract [en]

    One of the main drawbacks that limits the application of mineral trioxide aggregate (MTA) in dental field is its long setting time. Mineral trioxide aggregate with accelerated setting properties and excellent chemical-physical and biological properties is still required. In this study, an innovative mineral trioxide aggregate, which consists of calcium silicates, calcium aluminates, and zirconium oxide, was designed to obtain fast-setting property. The optimized formulation can achieve initial setting in 10 min and final setting in 15 min, which are much faster than commercial mineral trioxide aggregate. In addition, the optimized fast-setting MTA showed adequate radiopacity and good biocompatibility. The ion concentrations after storage in water for 1 day were 52.3 mg/L Ca, 67.7 mg/L Al, 48.8 mg/L Si, and 11.7 mg/L Mg. The hydration products of hardened cements were investigated by X-ray diffraction, scanning electron microscopy, and Fourier transform infrared, showing the accelerated setting time was due to the formation of honeycomb-like calcium silicate hydrate gel. The novel MTA could be a promising material for dental applications.

  • 40.
    Claverie, Marion
    et al.
    Univ Pau & Pays Adour, IPREM, CNRS, E2S,UPPA, F-64600 Anglet, France..
    McReynolds, Colin
    Univ Pau & Pays Adour, IPREM, CNRS, E2S,UPPA, F-64600 Anglet, France..
    Petitpas, Arnaud
    Univ Pau & Pays Adour, IPREM, CNRS, E2S,UPPA, F-64600 Anglet, France..
    Thomas, Martin
    Univ Pau & Pays Adour, IPREM, CNRS, E2S,UPPA, F-64600 Anglet, France..
    Fernandes, Susana C. M.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Univ Pau & Pays Adour, IPREM, CNRS, E2S,UPPA, F-64600 Anglet, France..
    Marine-Derived Polymeric Materials and Biomimetics: An Overview2020In: Polymers, E-ISSN 2073-4360, Vol. 12, no 5, article id 1002Article, review/survey (Refereed)
    Abstract [en]

    The review covers recent literature on the ocean as both a source of biotechnological tools and as a source of bio-inspired materials. The emphasis is on marine biomacromolecules namely hyaluronic acid, chitin and chitosan, peptides, collagen, enzymes, polysaccharides from algae, and secondary metabolites like mycosporines. Their specific biological, physicochemical and structural properties together with relevant applications in biocomposite materials have been included. Additionally, it refers to the marine organisms as source of inspiration for the design and development of sustainable and functional (bio)materials. Marine biological functions that mimic reef fish mucus, marine adhesives and structural colouration are explained.

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  • 41.
    Darvishi, Sorour
    et al.
    Univ Cambridge, Dept Chem Engn & Biotechnol, Philippa Fawcett Dr, Cambridge CB3 0AS, England.;Ecole Polytech Fed Lausanne, Dept Chem & Chem Engn, CH-1951 Sion, Switzerland.
    Tavakoli, Shima
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Kharaziha, Mahshid
    Isfahan Univ Technol, Dept Mat Engn, Esfahan 8415683111, Iran.
    Girault, Hubert H.
    Ecole Polytech Fed Lausanne, Dept Chem & Chem Engn, CH-1951 Sion, Switzerland.
    Kaminski, Clemens F.
    Univ Cambridge, Dept Chem Engn & Biotechnol, Philippa Fawcett Dr, Cambridge CB3 0AS, England.
    Mela, Ioanna
    Univ Cambridge, Dept Chem Engn & Biotechnol, Philippa Fawcett Dr, Cambridge CB3 0AS, England.
    Advances in the Sensing and Treatment of Wound Biofilms2022In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 61, no 13, article id 202112218Article, review/survey (Refereed)
    Abstract [en]

    Wound biofilms represent a particularly challenging problem in modern medicine. They are increasingly antibiotic resistant and can prevent the healing of chronic wounds. However, current treatment and diagnostic options are hampered by the complexity of the biofilm environment. In this review, we present new chemical avenues in biofilm sensors and new materials to treat wound biofilms, offering promise for better detection, chemical specificity, and biocompatibility. We briefly discuss existing methods for biofilm detection and focus on novel, sensor-based approaches that show promise for early, accurate detection of biofilm formation on wound sites and that can be translated to point-of-care settings. We then discuss technologies inspired by new materials for efficient biofilm eradication. We focus on ultrasound-induced microbubbles and nanomaterials that can both penetrate the biofilm and simultaneously carry active antimicrobials and discuss the benefits of those approaches in comparison to conventional methods.

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  • 42.
    Diba, Mani
    et al.
    Radboud Univ Nijmegen Med Ctr, Dept Biomat, NL-6525 EX Nijmegen, Netherlands..
    An, Jie
    Radboud Univ Nijmegen Med Ctr, Dept Biomat, NL-6525 EX Nijmegen, Netherlands..
    Schmidt, Stephan
    Heinrich Heine Univ Dusseldorf, Inst Organ & Macromol Chem, D-40225 Dusseldorf, Germany..
    Hembury, Mathew
    Univ Utrecht, Fac Sci, UIPS, Dept Pharmaceut, NL-3508 TB Utrecht, Netherlands..
    Ossipov, Dmitri
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Boccaccini, Aldo R.
    Univ Erlangen Nurnberg, Dept Mat Sci & Engn, Inst Biomat, D-91058 Erlangen, Germany..
    Leeuwenburgh, Sander C. G.
    Radboud Univ Nijmegen Med Ctr, Dept Biomat, NL-6525 EX Nijmegen, Netherlands..
    Exploiting Bisphosphonate-Bioactive-Glass Interactions for the Development of Self-Healing and Bioactive Composite Hydrogels2016In: Macromolecular rapid communications, ISSN 1022-1336, E-ISSN 1521-3927, Vol. 37, no 23, p. 1952-1959Article in journal (Refereed)
    Abstract [en]

    Hydrogels are widely recognized as promising candidates for various biomedical applications, such as tissue engineering. Recently, extensive research efforts have been devoted to the improvement of the biological and mechanical performance of hydrogel systems by incorporation of functional groups and/or inorganic particles in their composition. Bisphosphonates are a class of drugs, commonly used for treatment of osteoporosis, which exhibit a strong binding affinity for hydroxyapatite. In this study, the binding affinity of a bisphosphonate-functionalized polymer, hyaluronan, toward a bioactive glass (i.e., 45S5 Bioglass) is evaluated using force-distance measurements with atomic force microscopy. The strong interaction between bisphosphonate and bioactive glass is then exploited to develop organic-inorganic composite hydrogels and the viscoelastic and self-healing ability of these materials are investigated. Finally, the stability and mineralization behavior of these hydrogels are evaluated in simulated body fluid. Following this approach, injectable, bioactive and self-healing organic-inorganic composite hydrogels are produced, which mineralize abundantly and rapidly in simulated body fluid. These properties render these composite gels suitable for applications in bone-tissue engineering.

  • 43.
    Edin, Elle
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Composite Regenerative Scaffolds2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Regenerative medicine and tissue engineering solutions of heavily innervated tissues are at this point lacklustre. This thesis expands our knowledge of appropriate acellular scaffolds for tissue repair in general and nerve regeneration in particular. The optimal surgical procedure for the implantation of artificial extracellular matrix (ECM) was evaluated for recombinant human collagen (RHCIII) implants. Suturing techniques, as well as the usage of human amniotic membrane “bandages” were evaluated. While complete regeneration of corneal tissues occurred, only slight differences in effects of surgical technique could be found.

    The safety and efficacy of clinical trials using mesenchymal stromal cells (MSCs) was evaluated by conducting a systematic review and meta-analysis. MSC therapy was shown to be safe, with no increases mortality, rehospitalization or adverse events. There was also an indication of efficacy, as the overall mortality in the studies included was significantly smaller in the MSC treated group.

    Multicomponent hydrogel capsules encapsulating single cells were developed. Capsules manufactured from gelatin, agarose and fibrinogen were compared to pure gelatin capsules. The composite capsules successfully delayed cell release and prolonged cell survival.

    Surface patterning of collagen based biomimetic corneas was performed by microcontact printing. The ability of different sizes of fibronectin stripes to stimulate cell adhesion and proliferation was compared. The patterned surfaces improved cell adhesion, as well as proliferation markers.

    Conductive polymer composites were manufactured for use as nerve guides. The guides were created from electrospun polycaprolactone fibers coated with a series of different poly(3,4-ethylenedioxythiophene) films. A comparison of nerve progenitor growth and differentiation on the composite fibers was performed. Both the effects of fiber composition and MSC co-culture was investigated, with or without electrostimulation. MSC treatments and polymer coating was both important for nerve cell differentiation and growth.

    List of papers
    1. Effect of Surgical Technique on Corneal Implant Performance.
    Open this publication in new window or tab >>Effect of Surgical Technique on Corneal Implant Performance.
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    2014 (English)In: Translational Vision Science & Technology, E-ISSN 2164-2591, Vol. 3, no 2, article id 6Article in journal (Refereed) Published
    Abstract [en]

    PURPOSE: Our aim was to determine the effect of a surgical technique on biomaterial implant performance, specifically graft retention.

    METHODS: Twelve mini pigs were implanted with cell-free, 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC)/N-hydroxysuccinimide (NHS) cross-linked recombinant human collagen type III (RHCIII) hydrogels as substitutes for donor corneal allografts using overlying sutures with or without human amniotic membrane (HAM) versus interrupted sutures with HAM. The effects of the retention method were compared as well as the effects of collagen concentration (13.7% to 15% RHCIII).

    RESULTS: All implanted corneas showed initial haze that cleared with time, resulting in corneas with optical clarity matching those of untreated controls. Biochemical analysis showed that by 12 months post operation, the initial RHCIII implants had been completely remodeled, as type I collagen, was the major collagenous protein detected, whereas no RHCIII could be detected. Histological analysis showed all implanted corneas exhibited regeneration of epithelial and stromal layers as well as nerves, along with touch sensitivity and tear production. Most neovascularization was seen in corneas stabilized by interrupted sutures.

    CONCLUSIONS: This showed that the surgical technique used does have a significant effect on the overall performance of corneal implants, overlying sutures caused less vascularization than interrupted sutures.

    TRANSLATIONAL RELEVANCE: Understanding the significance of the suturing technique can aid the selection of the most appropriate procedure when implanting artificial corneal substitutes. The same degree of regeneration, despite a higher collagen content indicates that future material development can progress toward stronger, more resistant implants.

    Keywords
    biomaterials, biosynthetic cornea, corneal regeneration, corneal transplantation, recombinant human collagen
    National Category
    Surgery
    Identifiers
    urn:nbn:se:uu:diva-364450 (URN)10.1167/tvst.3.2.6 (DOI)24749003 (PubMedID)
    Available from: 2018-10-29 Created: 2018-10-29 Last updated: 2021-04-23
    2. Conductive PEDOT based coatings on microfibrous scaffolds: a nerve guide component
    Open this publication in new window or tab >>Conductive PEDOT based coatings on microfibrous scaffolds: a nerve guide component
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    2018 (English)Manuscript (preprint) (Other (popular science, discussion, etc.))
    National Category
    Biomaterials Science
    Identifiers
    urn:nbn:se:uu:diva-364452 (URN)
    Available from: 2018-10-29 Created: 2018-10-29 Last updated: 2018-10-29
    3. Mesenchymal Stromal Cells for the Treatment of Ischemic Injury and Vascular Trauma: A Systematic Review and Meta-Analysis
    Open this publication in new window or tab >>Mesenchymal Stromal Cells for the Treatment of Ischemic Injury and Vascular Trauma: A Systematic Review and Meta-Analysis
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    2018 (English)Manuscript (preprint) (Other (popular science, discussion, etc.))
    National Category
    Other Clinical Medicine
    Identifiers
    urn:nbn:se:uu:diva-364451 (URN)
    Available from: 2018-10-29 Created: 2018-10-29 Last updated: 2018-10-29
    4. Functional fabrication of recombinant human collagen-phosphorylcholine hydrogels for regenerative medicine applications.
    Open this publication in new window or tab >>Functional fabrication of recombinant human collagen-phosphorylcholine hydrogels for regenerative medicine applications.
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    2015 (English)In: Acta Biomaterialia, ISSN 1742-7061, E-ISSN 1878-7568, Vol. 12, p. 70-80, article id S1742-7061(14)00486-3Article in journal (Refereed) Published
    Abstract [en]

    The implant-host interface is a critical element in guiding tissue or organ regeneration. We previously developed hydrogels comprising interpenetrating networks of recombinant human collagen type III and 2-methacryloyloxyethyl phosphorylcholine (RHCIII-MPC) as substitutes for the corneal extracellular matrix that promote endogenous regeneration of corneal tissue. To render them functional for clinical application, we have now optimized their composition and thereby enhanced their mechanical properties. We have demonstrated that such optimized RHCIII-MPC hydrogels are suitable for precision femtosecond laser cutting to produce complementing implants and host surgical beds for subsequent tissue welding. This avoids the tissue damage and inflammation associated with manual surgical techniques, thereby leading to more efficient healing. Although we previously demonstrated in clinical testing that RHCIII-based implants stimulated cornea regeneration in patients, the rate of epithelial cell coverage of the implants needs improvement, e.g. modification of the implant surface. We now show that our 500μm thick RHCIII-MPC constructs comprising over 85% water are suitable for microcontact printing with fibronectin. The resulting fibronectin micropatterns promote cell adhesion, unlike the bare RHCIII-MPC hydrogel. Interestingly, a pattern of 30μm wide fibronectin stripes enhanced cell attachment and showed the highest mitotic rates, an effect that potentially can be utilized for faster integration of the implant. We have therefore shown that laboratory-produced mimics of naturally occurring collagen and phospholipids can be fabricated into robust hydrogels that can be laser profiled and patterned to enhance their potential function as artificial substitutes of donor human corneas.

    Keywords
    Collagen, Cornea, Hydrogel, Laser profiling, Surface modification
    National Category
    Biomaterials Science
    Identifiers
    urn:nbn:se:uu:diva-364449 (URN)10.1016/j.actbio.2014.10.035 (DOI)25448347 (PubMedID)
    Available from: 2018-10-29 Created: 2018-10-29 Last updated: 2018-10-29
    5. Controlled Delivery of Human Cells by Temperature Responsive Microcapsules.
    Open this publication in new window or tab >>Controlled Delivery of Human Cells by Temperature Responsive Microcapsules.
    Show others...
    2015 (English)In: Journal of Functional Biomaterials, ISSN 2079-4983, E-ISSN 2079-4983, Vol. 6, no 2, p. 439-53Article in journal (Refereed) Published
    Abstract [en]

    Cell therapy is one of the most promising areas within regenerative medicine. However, its full potential is limited by the rapid loss of introduced therapeutic cells before their full effects can be exploited, due in part to anoikis, and in part to the adverse environments often found within the pathologic tissues that the cells have been grafted into. Encapsulation of individual cells has been proposed as a means of increasing cell viability. In this study, we developed a facile, high throughput method for creating temperature responsive microcapsules comprising agarose, gelatin and fibrinogen for delivery and subsequent controlled release of cells. We verified the hypothesis that composite capsules combining agarose and gelatin, which possess different phase transition temperatures from solid to liquid, facilitated the destabilization of the capsules for cell release. Cell encapsulation and controlled release was demonstrated using human fibroblasts as model cells, as well as a therapeutically relevant cell line-human umbilical vein endothelial cells (HUVECs). While such temperature responsive cell microcapsules promise effective, controlled release of potential therapeutic cells at physiological temperatures, further work will be needed to augment the composition of the microcapsules and optimize the numbers of cells per capsule prior to clinical evaluation.

    Keywords
    cell delivery, cell encapsulation, human fibroblast, human umbilical vein endothelial cells, hydrogel, microcapsules, temperature responsive
    National Category
    Biomaterials Science
    Identifiers
    urn:nbn:se:uu:diva-364448 (URN)10.3390/jfb6020439 (DOI)26096147 (PubMedID)
    Available from: 2018-10-29 Created: 2018-10-29 Last updated: 2018-10-29
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  • 44.
    Eimont, R.
    et al.
    Ferentis UAB, Savanorių 231, LT-02300, Vilnius, Lithuania; Department of Nanoengineering, Center for Physical Sciences and Technology, Savanorių 231, LT-02300, Vilnius, Lithuania.
    Vailionytė, A.
    Ferentis UAB, Savanorių 231, LT-02300, Vilnius, Lithuania; Department of Nanoengineering, Center for Physical Sciences and Technology, Savanorių 231, LT-02300, Vilnius, Lithuania.
    Cėpla, V.
    Ferentis UAB, Savanorių 231, LT-02300, Vilnius, Lithuania; Department of Nanoengineering, Center for Physical Sciences and Technology, Savanorių 231, LT-02300, Vilnius, Lithuania.
    Druceikaitė, K.
    Ferentis UAB, Savanorių 231, LT-02300, Vilnius, Lithuania.
    Inokaitis, H.
    Institute of Anatomy, Lithuanian University of Health Sciences, Mickeviciaus 9, LT-43074, Kaunas, Lithuania.
    Dabkevičiūtė, L.
    Laboratory of Molecular Neurobiology, Neuroscience institute, Lithuanian University of Heath Sciences, Eiveniu 4, LT50161, Kaunas, Lithuania.
    Sukackaitė, E.
    Laboratory of Molecular Neurobiology, Neuroscience institute, Lithuanian University of Heath Sciences, Eiveniu 4, LT50161, Kaunas, Lithuania.
    Masilionis, I.
    Ferentis UAB, Savanorių 231, LT-02300, Vilnius, Lithuania; Department of Nanoengineering, Center for Physical Sciences and Technology, Savanorių 231, LT-02300, Vilnius, Lithuania.
    Ulčinas, A.
    Department of Nanoengineering, Center for Physical Sciences and Technology, Savanorių 231, LT-02300, Vilnius, Lithuania.
    Samanta, Ayan
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Valiokas, R.
    Ferentis UAB, Savanorių 231, LT-02300, Vilnius, Lithuania; Department of Nanoengineering, Center for Physical Sciences and Technology, Savanorių 231, LT-02300, Vilnius, Lithuania.
    Jekabsone, A.
    Laboratory of Molecular Neurobiology, Neuroscience institute, Lithuanian University of Heath Sciences, Eiveniu 4, LT50161, Kaunas, Lithuania.
    Extracellular matrix mimetics by crosslinked peptide hydrogels: application to neural 3D cell cultures2018In: International conference Vita Scientia Conference book, 2018, p. 59-59Conference paper (Other academic)
    Abstract [en]

    Self-supporting, shapeable hydrogels that consist of self-assembling synthetic peptides mimic the structural blocks of the extracellular matrix (ECM). Although they have been developed for regenerative medicine purposes, with a potential of grafting into patients without transplantation from organ donors, this class of materials are attractive as scaffolds for advanced cell culture/ in vitro tissue applications. In the present study, we have combined a series of peptides with functional motives (collagen, fibronectin, and laminin-like) for promoting granule layer-like organization of primary cerebellar cells and for controlling the cell attachment, neuritogenesis, cluster size and organization. We show that the micro/nanofabricated hydrogel scaffolds are applicable as multiwell plate inserts helping to analyse cell migration, differentiation, proliferation, adhesion, ultimately forming organotypic cell culture and artificial tissue structures.

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  • 45.
    Ek, Gustav
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Inorganic Chemistry.
    Jeschull, Fabian
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Bowden, Tim
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Brandell, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Li-ion batteries using electrolytes based on mixtures of poly(vinyl alcohol) and lithium bis(triflouromethane) sulfonamide salt2017In: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 246, p. 208-212Article in journal (Refereed)
    Abstract [en]

    Poly(vinyl alcohol) (PVA) has, to a limited degree, previously been investigated as an alternative host material to the dominating poly(ethylene oxide)-(PEO)-based polymer electrolytes used in electrochemical applications. These PVA-materials were found to be highly ionically conducting for a number of different salts at temperatures below the glass transition temperature, but in the presence of DMSO (dimethyl sulfoxide) residues. Here, we investigate the PVA:LiTFSI (lithium bis(triflouromethane) sulfonamide) electrolytes system, thereby for the first time using the salt most commonly explored in PEO-based systems also in PVA. It is shown that this results in significantly higher conductivities than for alternative Li salts. Comparisons between electrolytes casted in DMSO, H2O and hot-pressed samples confirm the necessity of solvent residues present in the DMSO casted films for the ionic transport, although no obvious liquid phase is formed. Moreover, we also show the feasibility of PVA-based electrolytes by construction of functional Li-metal broken vertical bar PVA-LiTFSI (DMSO) broken vertical bar LiFePO4 batteries operating at 60 degrees C, displaying stable capacities of 136 mAh/g LiFePO4 at a rate of C/20. (C) 2017 Elsevier Ltd. All rights reserved.

  • 46.
    Ekdahl, Kristina N
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology.
    Fromell, Karin
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Nilsson, Bo
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology.
    The innate immunity response: A key factor in biocompatibility2017In: Bioresorbable Polymers for Biomedical Applications: From Fundamentals to Translational Medicine / [ed] Giuseppe Perale & Jöns Hilborn, Elsevier, 2017, p. 85-94Chapter in book (Refereed)
  • 47.
    Ekdahl, Kristina N
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology. Linnaeus Univ, Linnaeus Ctr Biomat Chem, SE-39182 Kalmar, Sweden.
    Soveri, Inga
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Renal Medicine.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Fellström, Bengt
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Renal Medicine.
    Nilsson, Bo
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology.
    Cardiovascular disease in haemodialysis: role of the intravascular innate immune system.2017In: Nature Reviews Nephrology, ISSN 1759-5061, E-ISSN 1759-507X, Vol. 13, no 5, p. 285-296Article, review/survey (Refereed)
    Abstract [en]

    Haemodialysis is a life-saving renal replacement modality for end-stage renal disease, but this therapy also represents a major challenge to the intravascular innate immune system, which is comprised of the complement, contact and coagulation systems. Chronic inflammation is strongly associated with cardiovascular disease (CVD) in patients on haemodialysis. Biomaterial-induced contact activation of proteins within the plasma cascade systems occurs during haemodialysis and initially leads to local generation of inflammatory mediators on the biomaterial surface. The inflammation is spread by soluble activation products and mediators that are generated during haemodialysis and transported in the extracorporeal circuit back into the patient together with activated leukocytes and platelets. The combined effect is activation of the endothelium of the cardiovascular system, which loses its anti-thrombotic and anti-inflammatory properties, leading to atherogenesis and arteriosclerosis. This concept suggests that maximum suppression of the intravascular innate immune system is needed to minimize the risk of CVD in patients on haemodialysis. A potential approach to achieve this goal is to treat patients with broad-specificity systemic drugs that target more than one of the intravascular cascade systems. Alternatively, 'stealth' biomaterials that cause minimal cascade system activation could be used in haemodialysis circuits.

  • 48.
    Engstrand, Johanna
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Engqvist, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Polymers influencing the strength of injectable calcium phosphate bone cements-a preliminary study2012In: 22nd Interdisciplinary Research Conference on Biomaterials May 10th -12th, 2012, Uppsala, Swden.European Cells and Materials Vol 23 Suppl 3 2012 (page 32), 2012, p. 32-Conference paper (Refereed)
  • 49. Engstrand, Thomas
    et al.
    Kihlstrom, Lars
    Neovius, Erik
    Skogh, Ann-Charlott Docherty
    Lundgren, T. Kalle
    Jacobsson, Hans
    Bohlin, Jan
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Åberg, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Engqvist, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Development of a bioactive implant for repair and potential healing of cranial defects2014In: Journal of Neurosurgery, ISSN 0022-3085, E-ISSN 1933-0693, Vol. 120, no 1, p. 273-277Article in journal (Refereed)
    Abstract [en]

    The repair of complex craniofacial bone defects is challenging and a successful result is dependent on the size of the defect, quality of the soft tissue covering the defect, and choice of reconstruction method. The objective of this study was to develop a bioactive cranial implant that could provide a permanent reconstructive solution to the patient by stimulating bone healing of the defect. In this paper the authors report on the feasibility and clinical results of using such a newly developed device for the repair of a large traumatic and therapy-resistant cranial bone defect. The patient had undergone numerous attempts at repair, in which established methods had been tried without success. A mosaic-designed device was manufactured and implanted, comprising interconnected ceramic tiles with a defined calcium phosphate composition. The clinical outcome 30 months after surgery revealed a restored cranial vault without postoperative complications. Computed tomography demonstrated signs of bone ingrowth. Examination with combined 18F-fluoride PET and CT provided further evidence of bone healing of the cranial defect.

  • 50.
    Eriksson, Therese
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Amber, Mace
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Mindemark, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Brandell, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    The Role of Coordination Strength in Solid Polymer Electrolytes: Compositional Dependence of Transference Numbers in thePoly(ε-Caprolactone)–Poly(Trimethylene Carbonate) System2021In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 23, no 45, p. 25550-25557Article in journal (Refereed)
    Abstract [en]

    Both polyesters and polycarbonates have been proposed as alternatives to polyethers as host materials for future polymer electrolytes for solid-state lithium-ion batteries. While being comparatively similar functional groups, the electron density on the coordinating carbonyl oxygen is different, thereby rendering different coordinating strength towards lithium ions. In this study, the transport properties of poly(epsilon-caprolactone) and poly(trimethylene carbonate) as well as random copolymers of systematically varied composition of the two have been investigated, in order to better elucidate the role of the coordination strength. The cationic transference number, a property well-connected with the complexing ability of the polymer, was shown to depend almost linearly on the ester content of the copolymer, increasing from 0.49 for the pure poly(epsilon-caprolactone) to 0.83 for pure poly(trimethylene carbonate). Contradictory to the transference number measurements that suggest a stronger lithium-to-ester coordination, DFT calculations showed that the carbonyl oxygen in the carbonate coordinates more strongly to the lithium ion than that of the ester. FT-IR measurements showed the coordination number to be higher in the polyester system, resulting in a higher total coordination strength and thereby resolving the paradox. This likely originates in properties that are specific of polymeric solvent systems, e.g. steric properties and chain dynamics, which influence the coordination chemistry. These results highlight the complexity in polymeric systems and their ion transport properties in comparison to low-molecular-weight analogues, and how polymer structure and steric effects together affect the coordination strength and transport properties.

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