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  • 51.
    Hilborn, Jöns
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    In vivo injectable gels for tissue repair2011Inngår i: Wiley Interdisciplinary Reviews: Nanomedicine and Nanobiotechnology, ISSN 1939-5116, Vol. 3, nr 6, s. 589-606Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    The desire to reduce healthcare costs while improving outcomes drives minimally invasive methods to replacing traditional surgical procedures. Various treatments that would previously have needed open-type surgeries can be carried out using endoscopes, catheters, and needles. These advantages have become especially obvious for tissue engineering and regenerative medicine with in vivo gel injectable nanomaterials. In this review, the state of the art in this rapidly developing field is given. This is done by contrasting functional evaluation in vitro with in vivo followed by describing (1) synthetic materials, (2) the body's own polymers, (3) polymers in nature, (4) self-assembled peptides, and (5) new innovations and combinations. With increased understanding of the relationship between material characteristics and the outcome in vivo more rational design criteria are emerging.

  • 52.
    Hilborn, Jöns
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Varghese, Oommen P.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Jeronimo, B.
    Keynote: Safe and efficient in-vivo gene gene transfer and silencing technologies using natural pathways2012Inngår i: Journal of Tissue Engineering and Regenerative Medicine, ISSN 1932-6254, Vol. 6, nr suppl 1, s. 190-190Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    Introduction: The advance in nucleic acids therapeutic had been outstanding in recent years, which have opened new possibilities in regenerative medicine to tackle many serious diseases. To make nucleic acids based therapy a reality, the fundamental problem of tissue specific cellular delivery has to be accomplished. Here we present a new approach to develop the next generation of delivery vectors.

    Materials and methods: Hyaluronic acid were modified to complex DNA plasmids for luciferase transfection. Transfection: HCT 116 cells and mice where tranfected by adding HA-DNA complex. The transfection experiment with commercially available reagent polyethyleneimine (PEI) and plasmid alone were used as controls.

    Results and discussion: Efficient tranfection was shown using the new non toxic and safe non viral vector. Using ECM components (such as hyaluronic acid or HA) that allow both in vitroandin vivo transfection of plasmid DNA in CD44 positive cells. The chemically modified ECM components (non-toxic) binds to nucleic acids and are taken in by cells by natural receptor mediated endocytosis. The amount transported via these routes naturally is around 10 gram per day to give a potential capacity far exceeding the need for transfection if it is targeted. By molecular association strategies (joining the bandwagon) it is now possible for nucleic acids to follow these pathways that utilise the highly efficient receptor mediated endocytosis- door opener into cells.

  • 53.
    Holm Falk, Linus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC.
    An investigation of electrochemically mediated atom transfer radical polymerization as a method for polymerization of PEGMA for polymer electrolytes: A bachelor's degree project2019Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
  • 54.
    Huang, Xiao
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC, Organisk kemi.
    Conducting Redox Polymers for Electrode Materials: Synthetic Strategies and Electrochemical Properties2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Organic electrode materials represent an intriguing alternative to their inorganic counterparts due to their sustainable and environmental-friendly properties. Their plastic character allows for the realization of light-weight, versatile and disposable devices for energy storage. Conducting redox polymers (CRPs) are one type of the organic electrode materials involved, which consist of a π-conjugated polymer backbone and covalently attached redox units, the so-called pendant. The polymer backbone can provide conductivity while it is oxidized or reduced (i. e., p- or n-doped) and the concurrent redox chemistry of the pendant provides charge capacity. The combination of these two components enables CRPs to provide both high charge capacity and high power capability. This dyad polymeric framework provides a solution to the two main problems associated with organic electrode materials based on small molecules: the dissolution of the active material in the electrolyte, and the sluggish charge transport within the material. This thesis introduces a general synthetic strategy to obtain the monomeric CRPs building blocks, followed by electrochemical polymerization to afford the active CRPs material. The choice of pendant and of polymer backbone depends on the potential match between these two components, i.e. the redox reaction of the pendant and the doping of backbone occurring within the same potential region. In the thesis, terephthalate and polythiophene were selected as the pendant and polymer backbone respectively, to get access to low potential CRPs. It was found that the presence of a non-conjugated linker between polymer backbone and pendant is essential for the polymerizability of the monomers as well as for the preservation of individual redox activities. The resulting CRPs exhibited fast charge transport within the polymer film and low activation barriers for charge propagation. These low potential CRPs were designed as the anode materials for energy storage applications. The combination of redox active pendant as charge carrier and a conductive polymer backbone reveals new insights into the requirements of organic matter based electrical energy storage materials.

    Delarbeid
    1. Matching Diethyl Terephthalate with n-Doped Conducting Polymers
    Åpne denne publikasjonen i ny fane eller vindu >>Matching Diethyl Terephthalate with n-Doped Conducting Polymers
    Vise andre…
    2015 (engelsk)Inngår i: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 119, nr 33, s. 18956-18963Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    The combination of small, high charge capacity molecules as pendant groups with a conducting polymer backbone having good electronic conductivity upon doping, gives the possibility to design a high capacity conducting redox polymer material for electric energy storage applications. The desired synergetic effect of the two components requires energy matching as well as chemical compatibility of the pendant group and the polymer backbone. Here we investigate the matching of diethyl terephthalate (DeT) with the thiophene-based conducting polymers polythiophene (PT), poly(3,4-ethylenedioxythiophene) (PEDOT), and polyphenylthiophene. We show that a stable and well-defined electrochemical response of DeT is achieved, together with all conducting polymers except for PT in tetrabutylammonium hexafluorophosphate electrolyte, indicating good energy match as well as chemical compatibility between DeT and polymers. By varying the size of ammonium cations in the electrolytes, we further show how this size affects the conductivity and the cycling stability of the polymers and also that the n-doping performance of all conducting polymers can be improved by the use of smaller alkyl ammonium cations. On the basis of these results, we suggest that PEDOT and PT are suitable candidates for a polymer backbone in conducting redox polymers with DeT pendant groups.

    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-262423 (URN)10.1021/acs.jpcc.5b05067 (DOI)000360026200015 ()
    Forskningsfinansiär
    Swedish Foundation for Strategic Research Swedish Research CouncilCarl Tryggers foundation Swedish Energy Agency
    Tilgjengelig fra: 2015-09-17 Laget: 2015-09-15 Sist oppdatert: 2017-12-04bibliografisk kontrollert
    2. Synthesis and Redox Properties of Thiophene Terephthalate Building Blocks for Low-Potential Conducting Redox Polymers
    Åpne denne publikasjonen i ny fane eller vindu >>Synthesis and Redox Properties of Thiophene Terephthalate Building Blocks for Low-Potential Conducting Redox Polymers
    Vise andre…
    2015 (engelsk)Inngår i: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 119, nr 49, s. 27247-27254Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Terephthalate-substituted thiophene derivatives are promising redox-active components for anode materials in lithium-ion batteries. In this study, we present the synthesis of substituted 2-(thiophen-3-yl)terephthalate derivatives (TTDs) as suitable monomers for thiophene-based conducting redox polymers, along with their characterization by electrochemical and spectroscopic techniques. Density functional theory (DFT) calculations, utilizing the universal solvation model based on solute electron density (SMD), were used to predict both the first and the second reduction potentials of these TTDs. The computational results showed good agreement with the experimental data in nonaqueous acetonitrile solvent, with mean absolute errors of 30 and 40 mV for the first and second reduction steps, respectively. Time-dependent (TD) DFT calculations on TTDs indicated terephthalate local transitions at both 200 and 240 nm and charge-transfer transitions above 300 nm by examination of the involved molecular orbitals.

    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot nanoteknologi och funktionella material
    Identifikatorer
    urn:nbn:se:uu:diva-268481 (URN)10.1021/acs.jpcc.5b08518 (DOI)000366339000008 ()
    Forskningsfinansiär
    Swedish Research Council, VR 621-2011-4423Swedish Foundation for Strategic Research Swedish Energy Agency
    Tilgjengelig fra: 2015-12-05 Laget: 2015-12-05 Sist oppdatert: 2017-12-01bibliografisk kontrollert
    3. Conducting Redox Polymer Based Anode Materials for High Power Electrical Energy Storage
    Åpne denne publikasjonen i ny fane eller vindu >>Conducting Redox Polymer Based Anode Materials for High Power Electrical Energy Storage
    Vise andre…
    2016 (engelsk)Inngår i: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 204, s. 270-275Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    In this report we present the synthesis and characterization of two conducting redox polymers (CRPs) with polythiophene backbone and diethyl terephthalate pendant groups for the use as anode materials in secondary batteries. The materials show excellent rate capability allowing 301,Lm layers to be fully converted within seconds without the use of conductive additives. The high rate capability is traced to the open morphology of the materials that allows for fast ion transport, and to the mediation of electrons through the conducting polymer (CP) backbone. The requirements for the latter are i) that the redox chemistry of the pendant groups and the CP backbone overlaps and ii) that the CP conductivity is not compromised by the presence of the pendant groups. In the CRPs presented herein both these requirements are met and this is thus the first report on successful combination of the redox chemistry of organic redox molecules with the n-doping of conducting polymers.

    Emneord
    conducting redox polymers, terephthalates, polythiophene, n-doping
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-298055 (URN)10.1016/j.electacta.2016.03.163 (DOI)000376136700031 ()
    Forskningsfinansiär
    Swedish Foundation for Strategic Research Swedish Research CouncilCarl Tryggers foundation Stiftelsen Olle Engkvist ByggmästareSwedish Energy AgencyEU, Horizon 2020, 644631
    Tilgjengelig fra: 2016-07-05 Laget: 2016-06-29 Sist oppdatert: 2017-11-28bibliografisk kontrollert
    4. Effect of the Linker in Terephthalate-Functionalized Conducting Redox Polymers
    Åpne denne publikasjonen i ny fane eller vindu >>Effect of the Linker in Terephthalate-Functionalized Conducting Redox Polymers
    Vise andre…
    2016 (engelsk)Inngår i: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 222, s. 149-155Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Abstract The combination of high capacity redox active pendent groups and conducting polymers, realized in conducting redox polymers (CRPs), provides materials with high charge storage capacity that are electronically conducting which makes CRPs attractive for electrical energy storage applications. In this report, six polythiophene and poly(3,4-ethylenedioxythiophene)(PEDOT)-based CRPs with a diethyl terephthalate unit covalently bound to the polymer chain by various linkers have been synthesized and characterized electrochemically. The effects of the choice of polymer backbone and of the nature of the link on the electrochemistry, and in particular the cycling stability of these polymers, are discussed. All CRPs show both the doping of the polymer backbone as well as the redox behavior of the pendent groups and the redox potential of the pendent groups in the CRPs is close to that of corresponding monomer, indicating insignificant interaction between the pendant and the polymer backbone. While all CRPs show various degrees of charge decay upon electrochemical redox conversion, the PEDOT-based CRPs show significantly improved stability compared to the polythiophene counterparts. Moreover, we show that by the right choice of link the cycling stability of diethyl terephthalate substituted PEDOT-based CRPs can be significantly improved.

    Emneord
    conducting redox polymers, PEDOT, polythiophene, terephthalate
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot nanoteknologi och funktionella material
    Identifikatorer
    urn:nbn:se:uu:diva-310464 (URN)10.1016/j.electacta.2016.10.183 (DOI)000392566200018 ()
    Forskningsfinansiär
    Swedish Foundation for Strategic Research Swedish Research CouncilCarl Tryggers foundation Stiftelsen Olle Engkvist ByggmästareSwedish Energy AgencyEU, European Research Council, 644631
    Tilgjengelig fra: 2016-12-16 Laget: 2016-12-16 Sist oppdatert: 2017-11-29bibliografisk kontrollert
    5. A versatile route to polythiophenes with functional pendant groups using alkyne chemistry
    Åpne denne publikasjonen i ny fane eller vindu >>A versatile route to polythiophenes with functional pendant groups using alkyne chemistry
    Vise andre…
    2016 (engelsk)Inngår i: Beilstein Journal of Organic Chemistry, ISSN 2195-951X, E-ISSN 1860-5397, Vol. 12, s. 2682-2688Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    A new versatile polythiophene building block, 3-(3,4-ethylenedioxythiophene)prop-1-yne (pyEDOT) (3), is prepared from glycidol in four steps in 28% overall yield. pyEDOT features an ethynyl group on its ethylenedioxy bridge, allowing further functionalization by alkyne chemistry. Its usefulness is demonstrated by a series of functionalized polythiophene derivatives that were obtained by pre- and post-electropolymerization transformations, provided by the synthetic ease of the Sonogashira coupling and click chemistry.

    Emneord
    electropolymerization, functional polymers, polythiophene, Sonogashira coupling, thiophene
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot nanoteknologi och funktionella material
    Identifikatorer
    urn:nbn:se:uu:diva-310098 (URN)10.3762/bjoc.12.265 (DOI)000391506600001 ()
    Forskningsfinansiär
    Swedish Research Council, VR 621-2011-4423 2015-4870Swedish Foundation for Strategic Research Swedish Energy Agency
    Tilgjengelig fra: 2016-12-09 Laget: 2016-12-09 Sist oppdatert: 2017-11-29bibliografisk kontrollert
    6. Conducting redox polymers with non-activated charge transport properties
    Åpne denne publikasjonen i ny fane eller vindu >>Conducting redox polymers with non-activated charge transport properties
    Vise andre…
    2017 (engelsk)Inngår i: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 19, nr 36, s. 25052-25058Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Non-activated charge transport has been demonstrated in terephthalate-functionalized conducting redox polymers. The transition from a temperature-activated conduction mechanism to a residual scattering mechanism was dependent on the doping level. The latter mechanism is associated with apparent negative activation barriers to charge transport and is generally found in polymer materials with a high degree of order. Crystallographic data, however, suggested a low degree of order in this polymer, indicating the existence of interconnected crystal domains in the predominantly amorphous polymer matrix through which the charge was transported. We have thus shown that the addition of bulky pendant groups to conducting polymers does not prevent efficient charge transport via the residual scattering mechanism with low barriers to charge transport.

    sted, utgiver, år, opplag, sider
    Royal Society of Chemistry, 2017
    HSV kategori
    Forskningsprogram
    Teknisk fysik med inriktning mot nanoteknologi och funktionella material
    Identifikatorer
    urn:nbn:se:uu:diva-304625 (URN)10.1039/c7cp03939e (DOI)000411606200067 ()28879367 (PubMedID)
    Forskningsfinansiär
    Swedish Research CouncilSwedish Foundation for Strategic Research Stiftelsen Olle Engkvist ByggmästareEU, Horizon 2020, 64431Swedish Energy Agency
    Tilgjengelig fra: 2016-10-06 Laget: 2016-10-06 Sist oppdatert: 2018-06-04bibliografisk kontrollert
  • 55.
    Hulsart-Billström, Gry
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Bergman, Kristoffer
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Bowden, Tim
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Engstrand, Thomas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Hilborn, Jöns
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Larsson, Sune
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    The Effect of Incubation Time of Preformed Injectable Hydrogels on Bone Formation when used as Carrier for rhBMP-22011Inngår i: TERMIS-EU 2011 Abstracts, 2011Konferansepaper (Fagfellevurdert)
  • 56.
    Hulsart-Billström, Gry
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Hu, Qinghong
    Centre of Biopathways and Biomaterials, Dept of Chemistry, Zhejiang University, Hangzhou, Zhejiang, China .
    Bergman, Kristoffer
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Jonsson, Kenneth B
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Åberg, Jonas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Tang, Ruikang
    Centre of Biopathways and Biomaterials, Dept of Chemistry, Zhejiang University, Hangzhou, Zhejiang, China .
    Larsson, Sune
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Hilborn, Jöns
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Calcium phosphates compounds in conjunction with hydrogel as carrier for BMP-2: A study on ectopic bone formation in rats2011Inngår i: Acta Biomaterialia, ISSN 1742-7061, E-ISSN 1878-7568, Vol. 7, nr 8, s. 3042-3049Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Current treatment of fractures often involves the use of bone graft or bone morphogenetic proteins (BMP) to induce fracture healing, especially in patients with a compromised healing capacity. BMP has to be delivered in conjunction with a carrier. Unfortunately, there are drawbacks and limitations with current carriers, including their bovine origin which carries the risk of an immunological response. The physical properties also limit the use to open surgical procedures, as it cannot be injected. New carriers with improved properties are therefore needed. The aim of this study was to assess the ectopic bone forming capability of various calcium phosphate compounds when used in conjunction with a hydrogel as the carrier for BMP-2. Five different ceramic additives were tested, including beta-tricalcium phosphate and four types of hydroxyapatite (HAP) (nanoHAP, HAP, clods of HAP >100 mu m, and the biomimetic HAP Ostim35 (R)). The compounds were injected into the thigh muscle of rats, where it formed a gel in situ. After 4 weeks bone formation was evaluated by peripheral quantitative computed tomography and histology. The major finding was that the 20 nm nanoHAP yielded a higher bone density than the other additives (P = 0.0008, ANOVA with Tukey's multiple comparison test). We hypothesize that the higher bone density induced by nanoHAP might be due to nanocrystals of calcium phosphate acting as direct building blocks for biomineralization.

  • 57. Höglund, Odd V.
    et al.
    Hagman, Ragnvi
    Olsson, Kerstin
    Mindemark, Jonas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Borg, Niklas
    Lagerstedt, Anne-Sofie
    A new resorbable device for ligation of blood vessels - A pilot study2011Inngår i: Acta Veterinaria Scandinavica, ISSN 1751-0147, E-ISSN 1751-0147, Vol. 53, s. 47-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: During surgery, controlled haemostasis to prevent blood loss is vital for a successful outcome. It can be difficult to ligate vessels located deep in the abdomen. A device that is easy to use and enables secure ligatures could be beneficial. Cable ties made of nylon have been used for ligation but the non-resorbable material caused tissue reactions. The objective of this study was to use a resorbable material to construct a device with a self-locking mechanism and to test its mechanical strength and ligation efficiency. Methods: The device was manufactured by injection moulding of polydioxanone, a resorbable polymer used for suture materials. Polydioxanone with inherent viscosities of 1.9 dL/g and 1.3 dL/g were tested. The device consisted of a perforated flexible band which could be pulled through a case with a locking mechanism. After a first version of the device had been tested, some improvements were made. The locking case was downsized, corners were rounded off, the band was made thicker and the mould was redesigned to produce longer devices. Tensile tests were performed with the second version. The first version of the device was used to ligate the ovarian pedicle in a euthanized dog and to test echogenicity of the device with ultrasound. Compression of vessels of the ovarian pedicle was examined by histology. Both versions of the device were tested for haemostasis of and tissue grip on renal arteries in six anaesthetised pigs. Results: The tensile strength of the flexible band of the devices with inherent viscosity of 1.9 dL/g was 50.1 +/- 5.5 N (range 35.2-62.9 N, n = 11) and the devices with inherent viscosity of 1.3 dL/g had a tensile strength of 39.8 +/- 8.1 N (range 18.6-54.2 N, n = 11). Injection moulding of the polymer with lower inherent viscosity resulted in a longer flow distance. Both versions of the device had an effective tissue grip and complete haemostasis of renal arteries was verified. The device attached to the ovarian pedicle could be seen with ultrasound, and vessel compression and occlusion were verified by histology. Conclusions: Tests of functionality of the device showed complete haemostasis and good tissue grip. Devices with a band of sufficient length were easily applied and tightened in tissue.

  • 58.
    Jeong, Seung Hee
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Shou, Zhang
    Huazhong Univ Sci & Technol, State Key Lab Digital Mfg Equipment & Technol, Wuhan 430074, Peoples R China.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Hilborn, Jöns
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Wu, Zhigang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik. Huazhong Univ Sci & Technol, State Key Lab Digital Mfg Equipment & Technol, Wuhan 430074, Peoples R China.
    PDMS-Based Elastomer Tuned Soft, Stretchable, and Sticky for epidermal electronics2016Inngår i: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 28, nr 28, s. 5830-5836Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Targeting good user experiences, softness and stretchability are essential features for epidermal devices in body signal monitoring and body area stimulation. A highly soft, stretchable and sticky polydimethylsiloxane based elastomer (S3-PDMS) is achieved by a simple process with a widely used siloxane precursors, the properties of which are tuned by adding small fractions of an amine-based polymer, ethoxylated polyethylenimine (EPEI). This allows formation of a thick unobstrusive patch and may ease implementation of epidermal electronics in wearable healthcare applications. 

  • 59.
    Jeschull, Fabian
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Functional Binders at the Interface of Negative and Positive Electrodes in Lithium Batteries2015Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    In this thesis, electrode binders as vital components in the fabrication of composite electrodes for lithium-ion (LIB) and lithium-sulfur batteries (LiSB) have been investigated.

    Poly(vinylidene difluoride) (PVdF) was studied as binder for sulfur-carbon positive electrodes by a combination of galvanostatic cycling and nitrogen absorption. Poor binder swelling in the electrolyte and pore blocking in the porous carbon were identified as origins of low discharge capacity, rendering PVdF-based binders an unsuitable choice for LiSBs. More promising candidates are blends of poly(ethylene oxide) (PEO) and poly(N-vinylpyrrolidone) (PVP). It was found that these polymers interact with soluble lithium polysulfide intermediates generated during the cell reaction. They can increase the discharge capacity, while simultaneously improving the capacity retention and reducing the self-discharge of the LiSB. In conclusion, these binders improve the local electrolyte environment at the electrode interface.

    Graphite electrodes for LIBs are rendered considerably more stable in ‘aggressive’ electrolytes (a propylene carbonate rich formulation and an ether-based electrolyte) with the poorly swellable binders poly(sodium acrylate) (PAA-Na) and carboxymethyl cellulose sodium salt (CMC-Na). The higher interfacial impedance seen for the conventional PVdF binder suggests a protective polymer layer on the particles. By reducing the binder content, it was found that PAA-Na has a stronger affinity towards electrode components with high surface areas, which is attributed to a flexible polymer backbone and a higher density of functional groups.

    Lastly, a graphite electrode was combined with a sulfur electrode to yield a balanced graphite-sulfur cell. Due to a more stable electrode-electrolyte interface the self-discharge of this cell could be reduced and the cycle life was extended significantly. This example demonstrates the possible benefits of replacing the lithium metal negative electrode with an alternative electrode material.

    Delarbeid
    1. Functional, water-soluble binders for improved capacity and stability of lithium-sulfur batteries
    Åpne denne publikasjonen i ny fane eller vindu >>Functional, water-soluble binders for improved capacity and stability of lithium-sulfur batteries
    2014 (engelsk)Inngår i: Journal of Power Sources, ISSN 0378-7753, E-ISSN 1873-2755, Vol. 264, s. 8-14Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Binders based on mixtures of poly(ethylene oxide) (PEO) and poly(vinylpyrrolidone) (PVP) are here shown to significantly improve the reversible capacity and capacity retention of lithium- sulfur batteries compared to conventional binders. This mixed binder formulation combines the local improvement to the solvent system offered by PEO and the lithium (poly)sulfide-stabilising effect of PVP. Cells with cathodes made of simple mixtures of sulfur powder and carbon black with a binder of 4:1 PEO:PVP exhibited a reversible capacity of over 1000 mAh g(-1) at C/5 after 50 cycles and 800 mAh g(-1) at 1C after 200 cycles. Furthermore, these materials are water soluble, environmentally friendly and widely available, making them particularly interesting for large-scale production and applications in, for example, electric vehicles. 

    Emneord
    Lithium-sulfur, Binder, Poly(vinylpyrrolidone), Poly(ethylene oxide)
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-228938 (URN)10.1016/j.jpowsour.2014.04.090 (DOI)000337861800002 ()
    Forskningsfinansiär
    StandUp
    Tilgjengelig fra: 2014-08-11 Laget: 2014-07-24 Sist oppdatert: 2017-12-30
    2. Porosity Blocking in Highly Porous Carbon Black by PVdF Binder and Its Implications for the Li-S System
    Åpne denne publikasjonen i ny fane eller vindu >>Porosity Blocking in Highly Porous Carbon Black by PVdF Binder and Its Implications for the Li-S System
    2014 (engelsk)Inngår i: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 118, nr 45, s. 25890-25898Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    In this work, the influence of cathode binders on the porosity of composite electrodes for lithiumsulfur (LiS) batteries employing high surface area carbon blacks has been closely scrutinized. This has been accomplished by comparison of PVdF with the related copolymer, PVdF-HFP. Analysis of carbon black porosity after addition of binder in NMP solution reveals that PVdF(-HFP) fills pores of almost any size in carbon black, which can effect a severe reduction in pore volume and surface area accessible to the electrolyte in a LiS cell. Noting the different swelling behavior of both binders, the implications of pore filling by the binder on the electrochemistry of LiS cells can be determined. Because of the low swellability of PVdF in dimethoxyethane:dioxolane (DME:DOL)-based electrolytes, access of the electrolyte to the carbon surface area and pore volume is restricted, with potentially severe detrimental effects on the available capacity of the cell. Furthermore, this effect is still clearly significant for common binder loadings and with preinfiltration of sulfur; this study is therefore a clear demonstration that PVdF is an unsuitable choice of binder for the lithiumsulfur system and that alternatives must be considered.

    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-239773 (URN)10.1021/jp508137m (DOI)000344978000009 ()
    Forskningsfinansiär
    StandUp
    Tilgjengelig fra: 2014-12-30 Laget: 2014-12-30 Sist oppdatert: 2017-12-30
    3. Functional binders as graphite exfoliation suppressants in aggressive electrolytes for lithium-ion batteries
    Åpne denne publikasjonen i ny fane eller vindu >>Functional binders as graphite exfoliation suppressants in aggressive electrolytes for lithium-ion batteries
    2015 (engelsk)Inngår i: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 175, s. 141-150Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    A comparative study of various electrode binders for graphite electrodes was conducted in a carbonate-based electrolyte with a high content of propylene carbonate (PC) as a means to evaluate anode degradation in presence of different binders. Because of its direct contact with the active material, a binder can be interpreted as an interfacial layer and as a local part of the electrolyte, the properties of which greatly depend on the interaction with the liquid electrolyte. In this work we demonstrate how a carefully chosen binder can create a specific surface environment that can protect graphite from exfoliation when the binder exhibits poor solubility in the electrolyte solvent and good surface adhesion to the active material. The exceptional stability of graphite electrodes containing poly(acrylic acid) sodium salt (PAA-Na) and carboxymethyl cellulose sodium salt (CMC-Na), respectively, in a PC-rich electrolyte is explained through the understanding of binder swelling and functionality. Interfacial resistances and electrochemical stability were investigated with impedance spectroscopy and galvanostatic cycling. Electrode morphologies and distributions of material were analysed with SEM and EDX. Evidence is presented that the surface selectivity increases with concentration of functional groups and polymer flexibility. Therefore only the less selective, stiff polymer with less functional groups, CMC-Na, provides sufficient protection at low binder contents.

    Emneord
    Binder, graphite exfoliation, CMC, propylene carbonate, SEI
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-262960 (URN)10.1016/j.electacta.2015.03.072 (DOI)000360178600019 ()
    Forskningsfinansiär
    Swedish Research Council, 2012-3837
    Tilgjengelig fra: 2015-09-29 Laget: 2015-09-23 Sist oppdatert: 2017-12-01bibliografisk kontrollert
    4. A stable graphite negative electrode for the lithium-sulfur battery
    Åpne denne publikasjonen i ny fane eller vindu >>A stable graphite negative electrode for the lithium-sulfur battery
    2015 (engelsk)Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 51, nr 96, s. 17100-17103Artikkel i tidsskrift (Fagfellevurdert) Published
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-267760 (URN)10.1039/C5CC06666B (DOI)000367469400011 ()26451894 (PubMedID)
    Forskningsfinansiär
    Swedish Research Council, 2012-3837VINNOVAStandUp
    Tilgjengelig fra: 2015-11-26 Laget: 2015-11-26 Sist oppdatert: 2017-12-30
  • 60.
    Johansson, Patrik
    et al.
    Chalmers Univ. of Technol., Gothenburg, Sweden.
    Brandell, Daniel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Polymer Electrolytes (ISPE 2016)2017Inngår i: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 247, s. 564-568Artikkel i tidsskrift (Fagfellevurdert)
  • 61.
    Kadekar, Sandeep
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Nawale, Ganesh N.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Karlsson, Kira
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Ålander, Cecilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Podiyan, Oommen
    Bioengineering and Nanomedicine Lab, Faculty of Biomedical Sciences and Engineering, Tampere University of Technology, and BioMediTech Institute, 33720, Tampere, Finland.
    Varghese, Oommen P.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Synthetic design of asymmetric miRNA with engineered 3′-overhang to improve strand selection2019Inngår i: Molecular Therapy - Nucleic Acids, ISSN 2162-2531, E-ISSN 2162-2531, Vol. 16, s. 597-604Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We have developed a novel miRNA design that significantly improves strand selection within the RISC complex by engineering the 3′-end by adding extra nucleotides. Addition of seven nucleotides at the 3′-ends of the miR or miR* strand resulted in a thermodynamic asymmetry at either of the two-ends, which resulted in selective RISC recruitment as demonstrated by the stem-loop quantitative PCR experiment. Such selective recruitment was also corroborated at the protein level by Western blot analysis. In order to investigate the functional effect due to selective recruitment, we performed apoptosis and metastasis studies using human colon carcinoma cells (HCT116) and human osteosarcoma cells (MG63). These experiments indicated that the recruitment of miR strand is responsible for inducing apoptosis as well as to inhibit invasiveness of cancer cells. Recruitment of miR* strand, on the other hand, showed opposite effect. To the best of our knowledge, our strand engineering strategy is the first report of improved strand selection of desired miRNA strand by RISC without using any chemical modifications or mismatches. We believe such structural modifications of miR34a could mitigate some of the off-target effects of miRNA therapy and would also allow a better understanding of sequence-specific gene regulation. Such a design could also be adapted to other miRNA to enhance their therapeutic potential.

  • 62.
    Kamerlin, Natasha
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Fysikalisk kemi.
    Computer Simulations of Polymer Gels: Structure, Dynamics, and Deformation2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis presents the results of computer simulation studies of the structure, dynamics, and deformation of cross-linked polymer gels. Obtaining a fundamental understanding of the interrelation between the detailed structure and the properties of polymer gels is a challenge and a key issue towards designing materials for specific purposes. A new off-lattice method for constructing a closed network is presented that is free from defects, such as looping chains and dangling ends. Using these model networks in Brownian dynamics simulations, I show results for the structure and dynamics of bulk gels and describe a novel approach using spherical boundary conditions as an alternative to the periodic boundary conditions commonly used in simulations. This algorithm was also applied for simulating the diffusion of tracer particles within a static and dynamic network, to illustrate the quantitative difference and importance of including network mobility for large particles, as dynamic chains facilitate the escape of particles that become entrapped.

    I further investigate two technologically relevant properties of polymer gels: their stimuli-responsive behaviour and their mechanical properties. The collapse of core-shell nanogels was studied for a range of parameters, including the cross-linking degree and shell thickness. Two distinct regimes of gel collapse could be observed, with a rapid formation of small clusters followed by a coarsening stage. It is shown that in some cases, a collapsing shell may lead to an inversion of the core-shell particle which exposes the core polymer chains to the environment. This thesis also explores the deformation of bimodal gels consisting of both short and long chains, subject to uniaxial elongation, with the aim to understand the role of both network composition as well as structural heterogeneity on the mechanical response and the reinforcement mechanism of these materials. It is shown that a bimodal molecular weight distribution alone is sufficient to strongly alter the mechanical properties of networks compared to the corresponding unimodal networks with the same number-average chain length. Furthermore, it is shown that heterogeneities in the form of high-density short-chain clusters affect the mechanical properties relative to a homogeneous network, primarily by providing extensibility.

    Delarbeid
    1. Construction of a closed polymer network for computer simulations
    Åpne denne publikasjonen i ny fane eller vindu >>Construction of a closed polymer network for computer simulations
    2014 (engelsk)Inngår i: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 141, nr 15, s. 154113-Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Computer simulations are an important tool for linking the behaviour of polymer materials to the properties of the constituent polymer chains. In simulations, one normally uses periodic boundary conditions to mimic a macroscopic system. For a cross-linked polymer network, this will impose restrictions on the motion of the polymer chains at the borders of the simulation cell. We present a new method for constructing a three-dimensional closed network without periodic boundaries by embedding the system onto the surface of a sphere in four dimensions. This method can also be used to construct finite-sized gel particles for simulating the swelling of particles in a surrounding solvent. The method is described in algorithmic detail to allow the incorporation of the method into different types of simulation programs. We also present the results of Brownian dynamics simulations, analyzing the end-to-end distribution, radial distribution function, and the pore size distribution for different volume fractions and for chains with varying stiffness.

    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-239581 (URN)10.1063/1.4897447 (DOI)000344346000015 ()25338887 (PubMedID)
    Tilgjengelig fra: 2014-12-30 Laget: 2014-12-29 Sist oppdatert: 2017-12-05bibliografisk kontrollert
    2. Tracer diffusion in a polymer gel: simulations of static and dynamic 3D networks using spherical boundary conditions
    Åpne denne publikasjonen i ny fane eller vindu >>Tracer diffusion in a polymer gel: simulations of static and dynamic 3D networks using spherical boundary conditions
    2016 (engelsk)Inngår i: Journal of Physics: Condensed Matter, ISSN 0953-8984, E-ISSN 1361-648X, Vol. 28, nr 47, artikkel-id 475101Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    We have investigated an alternative to the standard periodic boundary conditions for simulating the diffusion of tracer particles in a polymer gel by performing Brownian dynamics simulations using spherical boundary conditions. The gel network is constructed by randomly distributing tetravalent cross-linking nodes and connecting nearest pairs. The final gel structure is characterised by the radial distribution functions, chain lengths and end-to-end distances, and the pore size distribution. We have looked at the diffusion of tracer particles with a wide range of sizes, diffusing in both static and dynamic networks of two different volume fractions. It is quantitatively shown that the dynamical effect of the network becomes more important in facilitating the diffusional transport for larger particle sizes, and that one obtains a finite diffusion also for particle sizes well above the maximum in the pore size distribution.

    Emneord
    tracer diffusion, Brownian dynamics simulation, polymer network, polymer gel, spherical boundary conditions, 3-sphere, hypersphere
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-307510 (URN)10.1088/0953-8984/28/47/475101 (DOI)000385445100001 ()27662260 (PubMedID)
    Tilgjengelig fra: 2016-11-21 Laget: 2016-11-17 Sist oppdatert: 2017-11-29bibliografisk kontrollert
    3. Collapse Dynamics of Core-Shell Nanogels
    Åpne denne publikasjonen i ny fane eller vindu >>Collapse Dynamics of Core-Shell Nanogels
    2016 (engelsk)Inngår i: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 49, nr 15, s. 5740-5749Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Stimuli-responsive core shell nanogels display collapse properties which are determined by both the core and the shell. We examine the equilibrium properties and the detailed structural changes during a collapse transition of polymer core shell nanoparticles using Brownian dynamics simulations. Gel particles with randomly distributed cross-linking nodes are created. The influence of the cross-linking degree, core/shell mass ratio, and the strength of the interparticle attractive interaction on the collapse behavior is investigated. Both collapsed core and collapsed shell structures are considered and compared with collapsed homopolymer networks. The transition time was found to be reduced with increasing cross-linking degree and inversely related to the depth of the Lennard-Jones potential. Similar to the kinetics of single chain collapse, there is an initial formation of clusters, in this case near cross-linking nodes, and a subsequent coarsening to form a compact globule. Where the nanogels were collapsed into a compact core, the deformation was found to be essentially symmetric, with a significantly slower relaxation time for the shell units compared to the core collapse transition time. Reducing the core size, the shell units were less affected by the presence of a collapsing core. For the system with a collapsing shell, our simulations reveal in some cases an inversion, with the shell compressing and eventually squeezing out the core units. This effect was more pronounced with decreasing cross-linking degree and core/shell mass ratio.

    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-303278 (URN)10.1021/acs.macromol.6b01206 (DOI)000381320300043 ()
    Tilgjengelig fra: 2016-09-16 Laget: 2016-09-15 Sist oppdatert: 2017-11-21bibliografisk kontrollert
    4. Deformation Behavior and Failure of Bimodal Networks
    Åpne denne publikasjonen i ny fane eller vindu >>Deformation Behavior and Failure of Bimodal Networks
    2017 (engelsk)Inngår i: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 50, nr 19, s. 7628-7635Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Using computer simulations, we have investigated the deformation and stress-strain behavior of a series of ideal gels without any defects, with a bimodal molecular weight distribution, subject to tensile strains. These networks were prepared with a spatially homogeneous distribution of short and long chains, where all chains are elastically active, without needing to consider possible effects of chain aggregation or entanglements on the physical properties. For all fractions of short chains, the first chains to rupture were the short chains that were initially oriented along the strain axis. The average orientation of the short chains slightly increased with decreasing fraction of short chains. This could be explained by the detailed structure of the network at different compositions. Analysis of the stress-strain relation for the short and long chains showed that the stress was not uniformly shared. Instead, the short chains are more strongly deformed whereas the long chains only make a negligible contribution at smaller strains. The mechanical properties of the bimodal networks at lower fractions of short chains also deviated from the behavior of equivalent unimodal networks with the corresponding average chain length, showing that bimodality alone is sufficient to increase both the maximum extensibility and toughness.

    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-332557 (URN)10.1021/acs.macromol.7b01653 (DOI)000412965900023 ()
    Tilgjengelig fra: 2017-10-30 Laget: 2017-10-30 Sist oppdatert: 2018-01-09bibliografisk kontrollert
    5. Deformation behaviour of homogeneous and heterogeneous bimodal networks
    Åpne denne publikasjonen i ny fane eller vindu >>Deformation behaviour of homogeneous and heterogeneous bimodal networks
    2017 (engelsk)Inngår i: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835Artikkel i tidsskrift (Fagfellevurdert) Submitted
    Abstract [en]

    In this study, the effect of spatial heterogeneities on the deformation behaviour and ultimate properties of bimodal gels consisting of both short and long chains was investigated by simulating the uniaxial elongation of defect-free networks containing dense short-chain clusters and comparing with gels having a homogeneous distribution of chains. In both cases, the first chains to rupture were the ones already aligned along the strain axis prior to imposing a strain. The presence of clusters was generally not found to improve the ultimate stress or toughness; the short chains within the clusters were effectively shielded from deformation, even at large fractions of short chains. The heterogeneous network tended to be weaker than the corresponding homogeneous network at a given fraction of short chains, fracturing before any signicant deformation of clusters had taken place. The deformation behaviour was, however, found to be sensitive to the degree of heterogeneity and the number of inter-cluster connections. At large fractions of short chains, clustering offered an improvement in the ultimate strain compared to a homogeneous bimodal network and also an equivalent unimodal network with the corresponding number-average chain length, thus providing a small improvement in toughness.

    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-332560 (URN)
    Tilgjengelig fra: 2017-10-30 Laget: 2017-10-30 Sist oppdatert: 2017-10-30
  • 63.
    Kamerlin, Natasha
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Fysikalisk kemi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Matematiska institutionen, Algebra och geometri.
    Elvingson, Christer
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Fysikalisk kemi.
    Collapse Dynamics of Core-Shell Nanogels2016Inngår i: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 49, nr 15, s. 5740-5749Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Stimuli-responsive core shell nanogels display collapse properties which are determined by both the core and the shell. We examine the equilibrium properties and the detailed structural changes during a collapse transition of polymer core shell nanoparticles using Brownian dynamics simulations. Gel particles with randomly distributed cross-linking nodes are created. The influence of the cross-linking degree, core/shell mass ratio, and the strength of the interparticle attractive interaction on the collapse behavior is investigated. Both collapsed core and collapsed shell structures are considered and compared with collapsed homopolymer networks. The transition time was found to be reduced with increasing cross-linking degree and inversely related to the depth of the Lennard-Jones potential. Similar to the kinetics of single chain collapse, there is an initial formation of clusters, in this case near cross-linking nodes, and a subsequent coarsening to form a compact globule. Where the nanogels were collapsed into a compact core, the deformation was found to be essentially symmetric, with a significantly slower relaxation time for the shell units compared to the core collapse transition time. Reducing the core size, the shell units were less affected by the presence of a collapsing core. For the system with a collapsing shell, our simulations reveal in some cases an inversion, with the shell compressing and eventually squeezing out the core units. This effect was more pronounced with decreasing cross-linking degree and core/shell mass ratio.

  • 64.
    Kamerlin, Natasha
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Fysikalisk kemi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Matematiska institutionen, Algebra och geometri.
    Elvingson, Christer
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Fysikalisk kemi.
    Deformation Behavior of Homogeneous and Heterogeneous Bimodal Networks2017Inngår i: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 50, nr 23, s. 9353-9359Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study, the effect of spatial heterogeneities on the deformation behavior during uniaxial elongation as well as the ultimate properties of bimodal gels consisting of both short and long chains was investigated by molecular simulations. Defect-free networks were created containing dense short-chain clusters and compared with gels having a homogeneous distribution of chains. In both cases, the first chains to rupture were the ones already aligned along the strain axis prior to imposing a strain. The presence of clusters was generally not found to improve the ultimate stress or toughness; the short chains within the clusters were effectively shielded from deformation, even at large fractions of short chains. The heterogeneous network tended to be weaker than the corresponding homogeneous network at a given fraction of short chains, fracturing before any significant deformation of clusters had taken place. The deformation behavior was, however, found to be sensitive to the degree of heterogeneity and the number of intercluster connections. At large fractions of short chains, clustering offered an improvement in the ultimate strain compared to a homogeneous bimodal network and also an equivalent unimodal network with the corresponding number-average chain length, thus providing a small improvement in toughness.

  • 65.
    Karlsson, Christoffer
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    Huang, Hao
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    Olsson, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    Strømme, Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    Gogoll, Adolf
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC.
    Sjödin, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    Poly(pyrrol-3-ylhydroquinone) – A Conducting Redox Polymer for Electric Energy Storage2013Konferansepaper (Fagfellevurdert)
  • 66.
    Karlsson, Rose-Marie Pernilla
    et al.
    KTH Royal Inst Technol, Wallenberg Wood Sci Ctr, Dept Fiber & Polymer Technol, Teknikringen 56, S-10044 Stockholm, Sweden.
    Larsson, Per Tomas
    KTH Royal Inst Technol, Wallenberg Wood Sci Ctr, Dept Fiber & Polymer Technol, Teknikringen 56, S-10044 Stockholm, Sweden;RISE Bioecon, Box 5604, S-11486 Stockholm, Sweden.
    Hansson, Per
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaci.
    Wågberg, Lars
    KTH Royal Inst Technol, Wallenberg Wood Sci Ctr, Dept Fiber & Polymer Technol, Teknikringen 56, S-10044 Stockholm, Sweden;KTH Royal Inst Technol, Div Fibre Technol, Dept Fiber & Polymer Technol, Teknikringen 56, S-10044 Stockholm, Sweden.
    Thermodynamics of the Water-Retaining Properties of Cellulose-Based Networks2019Inngår i: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 20, nr 4, s. 1603-1612Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Noncrystalline cellulose-based gel beads were used as a model material to investigate the effect of osmotic stress on a cellulosic network. The gel beads were exposed to osmotic stress by immersion in solutions with different concentrations of high molecular mass dextran and the equilibrium dimensional change of the gel beads was studied using optical microscopy. The volume fraction of cellulose was calculated from the volume of the gel beads in dextran solutions and their dry content and the relation between the cellulose volume fraction and the total osmotic pressure was thus obtained. The results show that the contribution to the osmotic pressure from counterions increases the water-retaining capacity of the beads at high osmotic pressures but also that the main factor controlling the gel bead collapse at high osmotic strains is the resistance to the deformation of the polymer chain network within the beads. Furthermore, the osmotic pressure associated with the deformation of the polymer network, which counteracts the deswelling of the beads, could be fitted to the Wall model indicating that the response of the cellulose polymer networks was independent of the charge of the cellulose. The best fit to the Wall model was obtained when the Flory-Huggins interaction parameter (chi) of the cellulose-water system was set to 0.55-0.60, in agreement with the well-established insolubility of high molecular mass beta-(1,4)-D-glucan polymers in water.

  • 67.
    Kheirabadi, Malihe
    et al.
    Sharif Univ Technol, Inst Nanosci & Nanotechnol, Tehran 1115589694, Iran..
    Bagheri, Reza
    Sharif Univ Technol, Inst Nanosci & Nanotechnol, Tehran 1115589694, Iran.;Sharif Univ Technol, Dept Mat Sci & Engn, Polymer Mat Res Grp, Tehran 111559466, Iran..
    Kabiri, Kourosh
    Iran Polymer & Petrochem Inst, Tehran 14965115, Iran..
    Ossipov, Dmitri A.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Jokar, Effat
    Sharif Univ Technol, Inst Nanosci & Nanotechnol, Tehran 1115589694, Iran..
    Asadian, Elham
    Sharif Univ Technol, Inst Nanosci & Nanotechnol, Tehran 1115589694, Iran..
    Improvement in Mechanical Performance of Anionic Hydrogels Using Full-Interpenetrating Polymer Network Reinforced with Graphene Oxide Nanosheets2016Inngår i: Advances in Polymer Technology, ISSN 0730-6679, E-ISSN 1098-2329, Vol. 35, nr 4, s. 386-395Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Weak mechanical possession is one of the limiting factors in application of hydrogels. To modify this inherent disadvantage, different approaches have been studied including synthesizing interpenetrating polymer network (IPN) and nanocomposite hydrogels. So, this study has focused on preparation of a novel full-IPN structure based on anionic monomers of 2-acrylamido-2-methylpropane sulfonic acid/acrylic acid-sodium acrylate via facile solution polymerization technique in an aqueous media with incorporation of graphene oxide (GO) nanosheets. Mechanical performance of materials in the as-prepared condition and swollen state was characterized via tensile, compression, and rheology tests, respectively. Significant improvement of both elastic and storage modulus (ca. four times higher than pure hydrogel) is observed in this approach. Also dynamic mechanical thermal analysis results revealed that incorporation of high GO content (0.5 wt%) can suppress formation of full-IPN structure, whereas low GO content has not such an effect, interestingly. Moreover, these novel hydrogels could easily be stretched or compressed followed by full recovery after unloading.

  • 68.
    Kisiel, Marta
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Ventura, M.
    George, Anu
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Hilborn, Jöns
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Varghese, Oommen P.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Critical Assessment of rhBMP-2 Mediated Bone Induction: an In Vitro and In Vivo Evaluation2012Inngår i: Journal of Tissue Engineering and Regenerative Medicine, ISSN 1932-6254, Vol. 6, nr SI, s. 39-39Artikkel i tidsskrift (Annet vitenskapelig)
  • 69.
    Kisiel, Marta
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Ventura, Manuela
    Podiyan, Oommen
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    George, Anu
    Walboomers, X Frank
    Hilborn, Jöns
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Varghese, Oommen P
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Critical assessment of rhBMP-2 mediated bone induction: An in vitro and in vivo evaluation.2012Inngår i: Journal of Controlled Release, ISSN 0168-3659, E-ISSN 1873-4995, Vol. 162, nr 3, s. 646-653Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Understanding the influence of formulation and storage conditions on rhBMP-2 bioactivity is extremely important for its clinical application. Reports in the literature show that different research groups employ different parameters such as formulation conditions, storage, doses for in vivo applications etc. that makes it difficult to correlate results from different experiments. We therefore decided to rationalize these anomalies by performing a basic study on such parameters using two commercially available BMPs. Our in vitro experiments suggest that BMPs from different sources have significant differences in their bioactivity. The clinically approved rhBMP-2 (InductOs®; BMP-P) showed superior stability, compared to rhBMP-2 from R&D Systems (BMP-R) at physiological pH (determined by ALP assay). This BMP-P also showed lower binding to polypropylene Eppendorf tube. The BMP-R almost lost its bioactivity within 30min at physiological pH and also shows more adhesion to plastic surfaces. This aggregation behavior was unequivocally ascertained by performing light scattering studies of the two BMPs, which revealed linear aggregation with time for BMP-R unlike BMP-P. The in vitro results were also reflected in the in vivo experiments, in a rat ectopic model with injectable hyaluronic acid (HA) hydrogel as BMP carrier. After 7weeks post-implantation we observed larger bone volume with oriented collagen in the BMP-P group but a smaller bone with disoriented collagen in the BMP-R case. Our results highlight the large difference in activity between seemingly identical substances and also the importance of proper handling of such sensitive proteins.

  • 70. Koens, Martin J. W.
    et al.
    Geutjes, Paul J.
    Faraj, Kaeuis A.
    Hilborn, Jöns
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Daamen, Willeke F.
    van Kuppevelt, Toin H.
    Organ-Specific Tubular and Collagen-Based Composite Scaffolds2011Inngår i: Tissue Engineering Part C: Methods, ISSN 1937-3384, Vol. 17, nr 3, s. 327-335Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The body contains a number of organs characterized by a tubular shape. In this study, we explored several methodologies for the construction of collagenous tubular scaffolds and films with defined (ultra) structure, length, diameter, orientation, and molecular composition. Standardization of molding, casting, freezing, and lyophilizing techniques using inexpensive materials and methods resulted in controllable fabrication of a wide variety of tubular and tissue-specific tubular scaffolds and films. Analysis included immunohistochemical and (ultra) structural examination. Handling and suturability were found adequate for tissue engineering applications.

  • 71.
    Kootala, Sujit
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Evaluation of Functionalized Biopolymers as a Step Toward Targeted Therapy of Osteoporosis2015Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The work presented in this thesis focuses on the development of strategies and smart bioactive materials for the treatment of osteoporosis. High and low molecular weight soluble hyaluronic acid-bisphosphonate (HA-BP) derivatives were investigated for their ability to inhibit osteoclasts. Low molecular weight HA-BP (L-HA-BP) was most effective in inhibiting active resorption of both murine and human osteoclasts (without affecting osteoblasts) compared to free bisphosphonate (BP). Precursor monocytes were unaffected, suggesting the specificity of HA-BP towards osteoclasts. This new class of functionalized hyaluronic acid could lead to rapid development of tailor-made pro-drugs for targeted treatment of osteoporosis.

    Polyphosphoesters (PEP) have been widely studied for their pro-osteoblast effects, primarily due to their involvement in cellular energy production pathway leading to the formation of inorganic phosphates that contribute to mineralized bone. Given that the effect of PEP on human osteoclasts is little studied, this work on poly(ethylene sodium phosphate) (PEP.Na) explores the potential to use PEP.Na as an inhibitor of osteoclast activity for the first time. PEP.Na exposure led to a dose-dependent toxicity of osteoclasts with reduction in their capacity to form resorption pits over 24h.

    Currently, there is a dearth of in vitro cell-culture systems that can study osteoclast-related resorption and osteoblast-related mineralization in a single co-culture system, and to simultaneously quantify the effects of soluble factors on these processes. Described here, is the development of a novel and simple two-sided co-culture system that can overcome these limitations with reliable and quantifiable readouts. In comparison with traditional one-sided co-culture systems, the two-sided co-culture was able to generate similar readouts for alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) markers. There is also the advantage of distinctly separate and quantifiable readouts for mineralization and resorption, which has been demonstrated using Pamidronate.

    Finally, HA-BP was synthesized with pre-determined amounts of BP groups. The BP groups attached to HA allowed the tunable incorporation of BMP-2 in hydrogels. The charge-based affinity of BMP-2 and BP allowed stable incorporation of specific amounts of BMP-2, which could be tuned by the ratio of BP groups. 125I-labelled BMP-2 was loaded into hydrogels and their release was studied. Radioactive measurements revealed the tunable sequestration and controlled release of protein over time. This result was corroborated by ALP measurements of cells exposed to released BMP-2. ALP production was found to be almost 5-fold higher in HA-BP hydrogels loaded with BMP-2 which suggested that the sequestered BMP-2 is not only available to cells but also remains highly potent, even in entrapped form, The release of BMP-2 is dependent upon the rate of diffusion, swelling in hydrogels and degradation pattern of the gels and may assist in the long-term and rapid regeneration of osteoblasts in vitro.

    Delarbeid
    1. Bisphosphonate-functionalized hyaluronic acid showing selective affinity for osteoclasts as a potential treatment for osteoporosis
    Åpne denne publikasjonen i ny fane eller vindu >>Bisphosphonate-functionalized hyaluronic acid showing selective affinity for osteoclasts as a potential treatment for osteoporosis
    Vise andre…
    2015 (engelsk)Inngår i: Biomaterials Science, ISSN 2047-4830, E-ISSN 2047-4849, Vol. 3, s. 1197-1207Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Current treatments for osteoporosis involve the administration of high doses of bisphosphonates (BPs) over a number of years. However, the efficiency of the absorption of these drugs and specificity towards targeted osteoclastic cells is still suboptimal. In this study, we have exploited the natural affinity of high (H) and low (L) molecular-weight hyaluronic acid (HA) towards a cluster of differentiation 44 (CD44) receptors on osteoclasts to use it as a biodegradable targeting vehicle. We covalently bonded BP to functionalised HA (HA–BP) and found that HA–BP conjugates were highly specific to osteoclastic cells and reduced mature osteoclast numbers significantly more than free BP. To study the uptake of HA–BP, we fluorescently derivatised the polymer–drug with fluorescein B isothiocyanate (FITC) and found that L-HA–BP could seamlessly enter osteoclastic cells. Alternatively, we tested polyvinyl alcohol (PVA) as a synthetic polymer delivery vehicle using similar chemistry to link BP and found that osteoclast numbers did not reduce in the same way. These findings could pave the way for biodegradable polymers to be used as vehicles for targeted delivery of anti-osteoporotic drugs.

    sted, utgiver, år, opplag, sider
    United Kingdom: , 2015
    Emneord
    Bisphosphonates, Osteoporosis, Hyaluronic acid, Osteoclasts, Osteoblasts, Bone
    HSV kategori
    Forskningsprogram
    Kemi med inriktning mot materialkemi; Kemi med inriktning mot polymerkemi
    Identifikatorer
    urn:nbn:se:uu:diva-258090 (URN)10.1039/C5BM00096C (DOI)000357937400003 ()26222035 (PubMedID)
    Prosjekter
    MultiTERM
    Forskningsfinansiär
    EU, European Research Council
    Merknad

    Erratum in Biomaterials Science 2015:3, issue 10, doi: 10.1039/c5bm90034d

    Tilgjengelig fra: 2015-07-10 Laget: 2015-07-10 Sist oppdatert: 2017-12-04bibliografisk kontrollert
    2. Anti-Resorptive Functions of Poly(ethylene sodium phosphate) on Human Osteoclasts
    Åpne denne publikasjonen i ny fane eller vindu >>Anti-Resorptive Functions of Poly(ethylene sodium phosphate) on Human Osteoclasts
    2015 (engelsk)Inngår i: Macromolecular Bioscience, ISSN 1616-5187, E-ISSN 1616-5195, Vol. 15, nr 12, s. 1634-1640Artikkel i tidsskrift (Fagfellevurdert) Published
    Emneord
    osteoclasts, osteoblasts, osteoporosis, poly(ethylene sodium phosphate)
    HSV kategori
    Forskningsprogram
    Kemi med inriktning mot materialkemi
    Identifikatorer
    urn:nbn:se:uu:diva-259078 (URN)10.1002/mabi.201500166 (DOI)000368456500001 ()26222677 (PubMedID)
    Forskningsfinansiär
    Swedish Research Council, 2014-6009
    Tilgjengelig fra: 2015-07-27 Laget: 2015-07-27 Sist oppdatert: 2017-12-04bibliografisk kontrollert
    3. Co-culture model using human osteoblasts and osteoclasts on bone discs for in situ monitoring of surface remodeling
    Åpne denne publikasjonen i ny fane eller vindu >>Co-culture model using human osteoblasts and osteoclasts on bone discs for in situ monitoring of surface remodeling
    (engelsk)Inngår i: Biomatter, ISSN 2159-2535Artikkel i tidsskrift (Annet vitenskapelig) Submitted
    Abstract [en]

    Osteoporosis is marked by accelerated bone resorption than bone formation and is currently treated with suboptimal drugs associated with severe off-target effects. More robust in vitro models are needed to investigate the precise pharmacokinetic effects of new drug formulations on bone cells in coculture conditions. This would promote targeted drug development and could reduce the number of animals needed in pre-clinical trials. However, existing coculture models do not address the effect of soluble factors released from cells in coculture. To address this challenge, we developed a two-sided co-culture model comprising human osteoclasts and osteoblasts on opposite sides of a thin decellurized bone chip. Essential cellular functions such as resorption by osteoclasts and mineralization by osteoblasts were not disrupted in the two-sided co-culture, even though the bone chip physically separated the two cell types. In this model, we freshly quantified resorption pits and mineralization on opposite sides of the same material through microscopy assisted image analysis and histological staining, respectively. Mineralization by osteoblasts was assessed with alizarin red and showed downregulation by 25% in the presence of osteoclasts (relative to osteoblasts alone) on the bone chip. The drug Pamidronate reduced the osteoclast population by 10% without affecting the number of osteoblasts. Thus, this co-culture model significantly simplifies allows in-situ monitoring of the effect of soluble bone signaling factors and anti-osteoporotic drugs.

    sted, utgiver, år, opplag, sider
    Taylor & Francis Group
    HSV kategori
    Forskningsprogram
    Kemi med inriktning mot polymerkemi; Kemi med inriktning mot materialkemi; Biologi med inriktning mot molekylärbiologi
    Identifikatorer
    urn:nbn:se:uu:diva-259080 (URN)
    Prosjekter
    MultiTERM
    Forskningsfinansiär
    EU, FP7, Seventh Framework Programme, 238551Swedish Research Council, 2014-6099
    Tilgjengelig fra: 2015-07-27 Laget: 2015-07-27 Sist oppdatert: 2015-09-01bibliografisk kontrollert
    4. Spatio-Temporal Control of Growth Factor Binding and Release in Bisphosphonate Functionalized Hydrogels Guides Rapid Differentiation of Precursor Cells in vitro
    Åpne denne publikasjonen i ny fane eller vindu >>Spatio-Temporal Control of Growth Factor Binding and Release in Bisphosphonate Functionalized Hydrogels Guides Rapid Differentiation of Precursor Cells in vitro
    Vise andre…
    (engelsk)Inngår i: Journal of materials chemistry. B, ISSN 2050-750X, E-ISSN 2050-7518Artikkel i tidsskrift (Fagfellevurdert) Submitted
    Abstract [en]

    An in situ cross-linkable hyaluronan hydrogel functionalized with bisphosphonate (BP) groups allows tunable release of bone morphogenetic protein-2 (BMP-2) determined by the amount of BP groups. Sequestration of BMP-2 in the hydrogel permits guided differentiation of entrapped progenitor cells in 3-D cultures. 

    sted, utgiver, år, opplag, sider
    Royal Society of Chemistry
    Emneord
    bisphosphonates, hydrogels, growth factors, tissue engineering, biomaterials
    HSV kategori
    Forskningsprogram
    Kemi med inriktning mot polymerkemi; Kemi med inriktning mot materialkemi
    Identifikatorer
    urn:nbn:se:uu:diva-259081 (URN)
    Forskningsfinansiär
    EU, European Research Council, 262948-2EU, FP7, Seventh Framework Programme, 238551
    Tilgjengelig fra: 2015-07-27 Laget: 2015-07-27 Sist oppdatert: 2017-12-04bibliografisk kontrollert
  • 72.
    Kootala, Sujit
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Rojas, Ramiro
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Hilborn, Jöns
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Novel hyaluronic acid hydrogels for spinal cord repair2012Inngår i: Journal of Tissue Engineering and Regenerative Medicine, ISSN 1932-6254, Vol. 6, nr suppl 1, s. 190-190Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    Spinal cord injury and repair is one of the important focus areas in tissue regeneration. Mechanical trauma caused due to factors such as contusion, compression or involuntary stretching induce post-traumatic secondary tissue damage in many Spinal Cord Injury (SCI) patients. Therefore, there is a need for scaffolds that provide a conducive threedimensionsal (3D) environment for injured cells to attach and grow. In this study we propose to synthesize 3D polymeric scaffolds in order to study the mechanical and adhesive properties & the nature of the interactions between hyaluronan-based (HY) biomaterials and cells and tissues both in vitroandin vivo. Here we have synthesized 3D HY-based hydrogels with robust mechanical and adhesive properties and demonstrate the use of this material for neuronal-related applications such as the treatment of SCI. Cell culture and survivability studies were done with NSC-34 cells. Live/Dead assay performed on the cells revealed significant differences in the staining of live cells and showed increased viability and proliferation. The number of live cells in the HY-based hydrogels with 0.1% collagen showed higher cell numbers compared with the other hydrogels. In this study we show that Injectable HYbased hydrogels with high elasticity, comparable to the mechanical properties of nervous tissue have been used in this study to study their biocompatibility and neuroprotective properties and they show better affinity for neuronal cells.

  • 73.
    Kootala, Sujit
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Zhang, Yu
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Ghalib, Sara
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Tolmachev, Vladmir
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för immunologi, genetik och patologi, Medicinsk strålningsvetenskap.
    Hilborn, Jöns
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Ossipov, Dmitri
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Control of growth factor binding and release in bisphosphonate functionalized hydrogels guides rapid diff erentiation of precursor cells in vitro2016Inngår i: Biomaterials Science, ISSN 2047-4830, E-ISSN 2047-4849, Vol. 4, nr 2, s. 250-254Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An in situ cross-linkable hyaluronan hydrogel functionalized with bisphosphonate (BP) groups allows tunable release of bone morphogenetic protein-2 (BMP-2) determined by the amount of BP groups. The high affinity of matrix-anchored BP groups towards BMP-2 permits guided differentiation of entrapped progenitor cells in 3-D cultures.

  • 74.
    Kootala, Sujit
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Zhang, Yu
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Ghalib, Sara
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Tolmachev, Vladmir
    Rudbeck Laboratory-Biomedical Radiation Sciences.
    Hilborn, Jöns
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Ossipov, Dmitri
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Spatio-Temporal Control of Growth Factor Binding and Release in Bisphosphonate Functionalized Hydrogels Guides Rapid Differentiation of Precursor Cells in vitroInngår i: Journal of materials chemistry. B, ISSN 2050-750X, E-ISSN 2050-7518Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An in situ cross-linkable hyaluronan hydrogel functionalized with bisphosphonate (BP) groups allows tunable release of bone morphogenetic protein-2 (BMP-2) determined by the amount of BP groups. Sequestration of BMP-2 in the hydrogel permits guided differentiation of entrapped progenitor cells in 3-D cultures. 

  • 75.
    Korolkovas, Airidas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Materialfysik. Inst Laue Langevin, Grenoble, France.
    Prévost, Sylvain
    Inst Laue Langevin, Grenoble, France.
    Kawecki, Maciej
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Materialfysik.
    Devishvili, Anton
    Inst Laue Langevin, Grenoble, France; Lund University, Dept Phys Chem, Lund, Sweden.
    Adlmann, Franz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Materialfysik.
    Gutfreund, Philipp
    Inst Laue Langevin, Grenoble, France.
    Wolff, Max
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Materialfysik.
    The viscoelastic signature underpinning polymer deformation under shear flow2019Inngår i: Soft Matter, ISSN 1744-683X, E-ISSN 1744-6848, Vol. 15, nr 3, s. 371-380Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Entangled polymers are deformed by a strong shear flow. The shape of the polymer, called the form factor, is measured by small angle neutron scattering. However, the real-space molecular structure is not directly available from the reciprocal-space data, due to the phase problem. Instead, the data has to be fitted with a theoretical model of the molecule. We approximate the unknown structure using piecewise straight segments, from which we derive an analytical form factor. We fit it to our data on a semi-dilute entangled polystyrene solution under in situ shear flow. The character of the deformation is shown to lie between that of a single ideal chain (viscous) and a cross-linked network (elastic rubber). Furthermore, we use the fitted structure to estimate the mechanical stress, and find a fairly good agreement with rheology literature.

  • 76.
    Lee, Tian Khoon
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi. Univ Kebangsaan Malaysia, Fuel Cell Inst, Bangi 43600, Selangor, Malaysia.
    Zaini, Nur Farahidayu Mohd
    Univ Kebangsaan Malaysia, Fac Sci & Technol, Sch Chem Sci & Food Technol, Bangi 43600, Selangor, Malaysia.
    Mobarak, Nadharatun Naiim
    Univ Kebangsaan Malaysia, Fac Sci & Technol, Sch Chem Sci & Food Technol, Bangi 43600, Selangor, Malaysia.
    Hassan, Nur Hasyareeda
    Univ Kebangsaan Malaysia, Fac Sci & Technol, Sch Chem Sci & Food Technol, Bangi 43600, Selangor, Malaysia.
    Noor, Siti Aminah Mohd
    Natl Def Univ Malaysia, Ctr Def Fdn Studies, Chem Dept, Kuala Lumpur 57000, Malaysia.
    Mamat, Shuhib
    Univ Kebangsaan Malaysia, Solar Energy Res Inst, Bangi 43600, Selangor, Malaysia.
    Loh, Kee Shyuan
    Univ Kebangsaan Malaysia, Fuel Cell Inst, Bangi 43600, Selangor, Malaysia.
    KuBulat, Ku Halim
    Univ Malaysia Terengganu, Sch Fundamental Sci, Kuala Nerus 21030, Terengganu, Malaysia.
    Su'ait, Mohd Sukor
    Univ Kebangsaan Malaysia, Solar Energy Res Inst, Bangi 43600, Selangor, Malaysia.
    Ahmad, Azizan
    Univ Kebangsaan Malaysia, Fac Sci & Technol, Sch Chem Sci & Food Technol, Bangi 43600, Selangor, Malaysia.
    PEO based polymer electrolyte comprised of epoxidized natural rubber material (ENR50) for Li-Ion polymer battery application2019Inngår i: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 316, s. 283-291Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Solid polymer electrolytes (SPE) of poly (ethylene oxide) (PEO) - 50% epoxidized natural rubber (ENR50) polymer blend doped with lithium bis(trifluoromethanesulfonyl) imide salt (LiTFSI) have achieved an optimum ionic conductivity value of 6.45 x 10(-5) S cm(-1) at 25 wt % of LiTFSI salt (room temperature). The chronoamperometry analysis indicated that the charge transport in polymer electrolyte is near-dominated by ion with lithium transference numbers (T-Li(+)) of 0.29. Notably, this electrolyte exhibits a good electrochemical stability of 4.2 V (vs. Li/Li+). Further investigation by IR has indicated that polymer-salt complexation occurred between Li+ from dopant salt with oxygen from the ether group (C-O-C). These have weaken the vibrational mode of methylene group (CH2); scissoring and rocking mode on plane as well as twisting mode for out of the plane. The strong complexation between the cations with the polymeric segments have indirectly increased the thermal stability of the polymer electrolytes. Nevertheless, using the facile blending method, the addition of environment benign and natural material of ENR50 has improved the PEO-based electrolyte system. 

  • 77.
    Lindh, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    Carlsson, Daniel O
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    Strømme, Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    Mihranyan, Albert
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    One-pot formation of 2,3-dialdehyde cellulose (DAC) beads2015Konferansepaper (Fagfellevurdert)
  • 78.
    Lindh, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material. Uppsala universitet.
    Carlsson, Daniel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    Vall, Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    Strömme, Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    Mihranyan, Albert
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    Spontaneous formation of 2,3-dialdehyde cellulose (DAC) beads via periodate oxidation and application of the beads as matrix material in protein purification2016Konferansepaper (Fagfellevurdert)
  • 79.
    Liu, Jun
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material. Jiangsu Univ, Sch Environm & Safety Engn, Biofuels Inst, Zhenjiang.
    Bacher, Markus
    Univ Nat Resources & Appl Life Sci BOKU, Dept Chem, Vienna.
    Rosenau, Thomas
    Univ Nat Resources & Appl Life Sci BOKU, Dept Chem, Vienna; Åbo Akad Univ, Lab Wood & Paper Chem, Johan Gadolin Proc Chem Ctr, Turku.
    Willfoer, Stefan
    Åbo Akad Univ, Lab Wood & Paper Chem, Johan Gadolin Proc Chem Ctr, Turku.
    Mihranyan, Albert
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Nanoteknologi och funktionella material.
    Potentially Immunogenic Contaminants in Wood-Based and Bacterial Nanocellulose: Assessment of Endotoxin and (1,3)-β-d-Glucan Levels2018Inngår i: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 19, nr 1, s. 150-157Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Knowledge gaps in the biosafety data of the nanocellulose (NC) for biomedical use through various routes of administration call for closer look at health and exposure evaluation. This work evaluated the potentially immunogenic contaminants levels, for example, endotoxin and (1,3)-β-d-glucan, in four representative NCs, that is, wood-based NCs and bacterial cellulose (BC). The hot-water extracts were analyzed with ELISA assays, HPSEC-MALLS, GC, and NMR analysis. Varying levels of endotoxin and (1,3)-β-d-glucan contaminats were found in these widely used NCs. Although the β-(1,3)-d-glucan was not detected from the NMR spectra due to the small extract samples amount (2–7 mg), the anomerics and highly diastereotopic 6-CH2 signals may suggest the presence of β-(1,4)-linkages with β-(1,6) branching in the polysaccharides of NCs’ hot-water extracts, which were otherwise not detectable in the enzymatic assay. In all, the article highlights the importance of monitoring various water-soluble potentially immunogenic contaminants in NC for biomedical use.

  • 80.
    López, Alejandro
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Persson, Cecilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Hilborn, Jöns
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Engqvist, Håkan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Injectable biodegradable composites for the degenerated intervertebral disc2010Inngår i: GRIBOI Congress, Turin, 2010, 2010Konferansepaper (Fagfellevurdert)
  • 81.
    López, Alejandro
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Persson, Cecilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Hilborn, Jöns
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Engqvist, Håkan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Synthesis and characterization of injectable composites of poly[D,L-lactide-co-(ε-caprolactone)] reinforced with β-TCP and CaCO3 for intervertebral disk augmentation.2010Inngår i: Journal of Biomedical Materials Research, Part B: Applied Biomaterials, ISSN 15524973, Vol. 95B, nr 1, s. 75-83Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Degeneration of the intervertebral disk constitutes one of the major causes of low back pain in adults aged 2050 years old. In this study, injectable, in situ setting, degradable composites aimed for intervertebral disk replacement were prepared. beta-TCP and calcium carbonate particles were mixed into acrylic-terminated oligo[D,L-lactide-co-(epsilon-caprolactone)], which were crosslinked at room temperature. The structure of the oligomers was confirmed by H-1-NMR spectroscopy. The composites were examined via SEM, and the mechanical properties of the crosslinked networks were determined. The porous beta-TCP particles showed good mechanical anchorage to the matrix due to polymer penetration into the pores. In vitro degradation tests showed that the composites containing beta-TCP slowly degraded, whereas the composites containing CaCO3 exhibited apatite formation capacity. It was concluded that the surface area, morphology, and solubility of the fillers might be used to control the degradation properties. The incorporation of fillers also increased both the elastic modulus and the maximum compression strength of the composites, properties that were similar to those of the physiological disk. These materials have potential for long-term intervertebral disk replacement and regenerative scaffolds because of their low degradation rates, bioactivity, and mechanical properties.

  • 82.
    López, Alejandro
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Persson, Cecilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Hilborn, Jöns
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Rojas, Ramiro
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Comparative characterization of oligomeric precursors intended for injectable implants2013Inngår i: Polymers for Advanced Technologies, ISSN 1042-7147, E-ISSN 1099-1581, Vol. 24, nr 1, s. 15-21Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The use of injectable materials is a simple approach for drug delivery and tissue repair, in, e.g. minimally invasive surgery applications. If these materials are used past their glass transition temperature and have a low viscosity, they will be able to flow while delivered in situ. Whether these materials are to be used as low viscosity drug carriers or further crosslinked for tissue repair, there is a need for a better understanding of their handling properties. In this study, oligo(trimethylene carbonate) (oTMC) and oligo[D,L-lactide-co-(«-caprolactone)] (oDLLA-co-CL) of various molecular weights within a relevant injectability range were synthesized via ring-opening polymerization. The materials were comparatively characterized by 1H NMR spectroscopy, differential scanning calorimetry, gel permeation chromatography, and rheological measurements. After comparing the viscosities and molecular weights of the materials, it was concluded that oDLLA-co-CLs were, gener- ally, better suited as an injectable in situ crosslinking network, whereas oTMCs were found to be better candidates as injectable drug carriers. This study provides useful data and guidelines on the use of these and other similar oligomers intended for injectable implants.

  • 83. Mamat, Shuhib
    et al.
    Faizzi, Mohamad
    Sukor Su'ait, Mohd
    Ahmad Ludin, Norasikin
    Sopian, Kamarauzzaman
    Akmaliah Dzulkurnain, Nurul
    UM Power Energy Dedicated Advanced Center ( UMPEDAC ) Wisma R&D.
    Ahmad, Azizan
    Kee Shyuan, Loh
    Tian Khoon, Lee
    Brandell, Daniel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    An Investigation of Modified Natural Rubber-Based (MG49) Polymer Electrolyte in Dye-Sensitized Solar Cells2018Inngår i: Sains Malaysiana, ISSN 0126-6039, Vol. 47, nr 11, s. 2667-2676Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A dye-sensitized solar cell (DSSC) was fabricated utilizing 49% poly(methyl methacrylate)-grafted natural rubber (MG49) with sodium iodide (NaI) as ion conducting membrane. The effect of NaI concentrations on electrochemical, morphological, chemical interaction and the crystallinity properties of MG49 has been analyzed by electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD), respectively. The highest ionic conductivity of 8.86 × 10-5 S cm-1 at room temperature for MG49-NaI (30 wt. %) polymer electrolyte membrane is achieved. The cross-sectional morphology showed a homogenous microporous structure of the membrane. Infrared analysis indicated that the interactions occurred between oxygen atoms from ether (C–O–C) and carbonyl (C=O) group of the polymer with sodium ions. XRD analysis showed the property of semi-crystalline phase reduced with the increases of salt concentration. The chronoamperometry analysis of MG49-NaI (30 wt. %) give an ionic transference number value of 0.92, proving that the polymer electrolyte membrane is ionic conductor and predominates by the number of ions presence. A fabricated solid-state dye-sensitized solar cell (DSSC) of FTO/TiO2-N719/MG49-NaI(30 wt.%)-I2/Pt under light intensity of 100 mW cm-2, gives results of the photovoltaic responses with Jsc, Voc, ff and efficiency of 1.30 mA cm-2, 0.56 V, 34.91 and 0.26%, respectively. In quasi-solid DSSC, an effieciencyof 3.48 % with Voc = 0.75 V, Jsc = 12.71 mA cm-2 and FF = 37.70 was achieved.

  • 84. Martinez-Sanz, Elena
    et al.
    Ossipov, Dmitri A.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Hilborn, Jöns
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Larsson, Sune
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Jonsson, Kenneth B.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Varghese, Oommen P.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Bone reservoir: Injectable hyaluronic acid hydrogel for minimal invasive bone augmentation2011Inngår i: Journal of Controlled Release, ISSN 0168-3659, E-ISSN 1873-4995, Vol. 152, nr 2, s. 232-240Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A strategy has been designed to develop hyaluronic acid (HA) hydrogel for in vivo bone augmentation using minimal invasive technique. A mild synthetic procedure was developed to prepare aldehyde modified HA by incorporating an amino-glycerol side chain via amidation reaction and selective oxidation of the pendent group. This modification, upon mixing with hydrazide modified HA formed hydrazone-crosslinked hydrogel within 30 s that was stable at physiological pH. In vitro experiments showed no cytotoxicity of hydrogel with the controlled release of active bone morphogenic protein-2 (BMP-2). In vivo evaluation of this gel as a BMP-2 carrier was performed by injecting gels over the rat calvarium and showed bone formation in 8 weeks in correlation with the amount of BMP-2 loaded (0, 1 and 30 pig) within the gel. Furthermore, hydrogels with 30 Kg of BMP-2 induced less bone formation upon subcutaneous injection in comparison with subperiosteal implantation. Histological examination showed newly formed bone with a high expression of osteocalcin, osteopontin and with angiogenic bone marrow when higher BMP-2 concentration was employed. Our result suggests that novel HA hydrogels could be used as a BMP-2 carrier and can promote bone augmentation for potential orthopedic applications.

  • 85.
    Martinez-Sanz, Elena
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Varghese, Oommen
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Kisiel, Marta
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Engstrand, Thomas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Reich, Karoline
    Bohner, Marc
    Jonsson, Kenneth B
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Ortopedi.
    Köhler, Thomas
    Müller, Ralph
    Ossipov, Dmitri
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Hilborn, Jöns
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Minimally invasive mandibular bone augmentation using injectable hydrogels2012Inngår i: Journal of Tissue Engineering and Regenerative Medicine, ISSN 1932-6254, Vol. 6, nr S3, s. s15-s23Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Hyaluronic acid-based hydrogels are proven biocompatible materials and excellent carriers of bone morphogenetic protein-2 (BMP-2) that have been successfully tested for bone generation in vivo. Different formulations, with or without nanohydroxyapatite, have shown promise for craniofacial applications. In this study, 28 rats were used to investigate whether it is possible to achieve mandibular bone augmentation upon injection of novel hyaluronic acid-based hydrogels containing nanohydroxyapatite and different concentrations of BMP-2 (0, 5 and 150ÎŒg/ml). The biomaterials were injected subperiosteally through fine needles into the innate mandibular diastema, imitating a clinical procedure for resorbed mandibles. No incisions, flaps or sutures were necessary. After 8weeks the mandibles were evaluated by peripheral quantitative computed tomography (pQCT), micro-computed tomography (ÎŒCT), histology, immunohistochemistry and fluorochrome labelling. As a result, engineered bone was observed in all treated mandibles, with a statistically significant increase in mandibular bone volume correlated with the amount of BMP-2 loaded in the hydrogel formula. We therefore demonstrated that minimally invasive mandibular bone augmentation is possible upon injection in rats, when using the appropriate injectable scaffolds. This represents an attractive clinical alternative for oral implantology patients.

  • 86.
    Mindemark, Jonas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Electrolytes for High-Performance Light-Emitting Electrochemical Cells: Going from Polyethers to Oligocarbonates2018Konferansepaper (Fagfellevurdert)
  • 87.
    Mindemark, Jonas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Functional Cyclic Carbonate Monomers and Polycarbonates: Synthesis and Biomaterials Applications2012Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The present work describes a selection of strategies for the synthesis of functional aliphatic polycarbonates. Using an end-group functionalization strategy, a series of DNA-binding cationic poly(trimethylene carbonate)s was synthesized for application as vectors for non-viral gene delivery. As the end-group functionality was identical in all polymers, the differences observed in DNA binding and in vitro transfection studies were directly related to the length of the hydrophobic poly(trimethylene carbonate) backbone and the number of functional end-groups. This enabled the use of this polymer system to explore the effects of structural elements on the gene delivery ability of cationic polymers, revealing striking differences between different materials, related to functionality and cationic charge density.

    In an effort to achieve more flexibility in the synthesis of functional polymers, polycarbonates were synthesized in which the functionalities were distributed along the polymer backbone. Through polymerization of a series of alkyl halide-functional six-membered cyclic carbonates, semicrystalline chloro- and bromo-functional homopolycarbonates were obtained. The tendency of the materials to form crystallites was related to the presence of alkyl as well as halide functionalities and ranged from polymers that crystallized from the melt to materials that only crystallized on precipitation from a solution. Semicrystallinity was also observed for random 1:1 copolymers of some of the monomers with trimethylene carbonate, suggesting a remarkable ability of repeating units originating from these monomers to form crystallites.

    For the further synthesis of functional monomers and polymers, azide-functional cyclic carbonates were synthesized from the bromo-functional monomers. These were used as starting materials for the click synthesis of triazole-functional cyclic carbonate monomers through Cu(I)-catalyzed azide–alkyne cycloaddition. The click chemistry strategy proved to be a viable route to obtain structurally diverse monomers starting from a few azide-functional precursors. This paves the way for facile synthesis of a wide range of novel functional cyclic carbonate monomers and polycarbonates, limited only by the availability of suitable functional alkynes.

    Delarbeid
    1. Efficient DNA Binding and Condensation Using Low Molecular Weight, Low Charge Density Cationic Polymer Amphiphiles
    Åpne denne publikasjonen i ny fane eller vindu >>Efficient DNA Binding and Condensation Using Low Molecular Weight, Low Charge Density Cationic Polymer Amphiphiles
    2010 (engelsk)Inngår i: Macromolecular rapid communications, ISSN 1022-1336, E-ISSN 1521-3927, Vol. 31, nr 15, s. 1378-1382Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    A new class of biodegradable cationic macromolecules for DNA binding and condensation was developed by end-group-functionalization of poly(trimethylene carbonate). A series of one- and two-armed structures was synthesized and their interaction with DNA was evaluated. To aid data interpretation, a non-linear modeling method was applied to show efficient DNA binding that was intimately related to cationic charge density and macromolecular architecture. One-armed, low charge density structures were consistently found to bind to DNA at lower charge ratios than their two-armed, high charge density counterparts. This suggests that polymer backbone structure and characteristics are important considerations in the development of efficient cationic polymer systems for DNA condensation and delivery.

    Emneord
    DNA condensation, gene delivery, ionomers, polyplexes, self-assembly
    HSV kategori
    Forskningsprogram
    Kemi med inriktning mot polymerkemi
    Identifikatorer
    urn:nbn:se:uu:diva-135391 (URN)10.1002/marc.201000141 (DOI)000280944700011 ()
    Tilgjengelig fra: 2010-12-07 Laget: 2010-12-06 Sist oppdatert: 2017-12-11bibliografisk kontrollert
    2. Low Charge Density Cationic Polymers for Gene Delivery: Exploring the Influence of Structural Elements on In Vitro Transfection
    Åpne denne publikasjonen i ny fane eller vindu >>Low Charge Density Cationic Polymers for Gene Delivery: Exploring the Influence of Structural Elements on In Vitro Transfection
    2012 (engelsk)Inngår i: Macromolecular Bioscience, ISSN 1616-5187, E-ISSN 1616-5195, Vol. 12, nr 6, s. 840-848Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    A series of end-functionalized poly(trimethylene carbonate) DNA carriers, characterized by low cationic charge density and pronounced hydrophobicity, was used to study structural effects on in vitro gene delivery. As the DNA-binding moieties were identical in all polymer structures, the differences observed between the different polymers were directly related to the functionality and length of the polymer backbone. The transfection efficiency and cytotoxicity of the polymer/DNA complexes were thus found to be dependent on a combination of polymer charge density and functionality, highlighting the importance of such structural considerations in the development of materials for efficient gene delivery.

    sted, utgiver, år, opplag, sider
    Wiley-VCH Verlagsgesellschaft, 2012
    Emneord
    amphiphiles, biodegradable, biological applications of polymers, gene delivery, transfection
    HSV kategori
    Forskningsprogram
    Kemi med inriktning mot polymerkemi
    Identifikatorer
    urn:nbn:se:uu:diva-169673 (URN)10.1002/mabi.201100480 (DOI)000304711200014 ()
    Tilgjengelig fra: 2012-03-05 Laget: 2012-03-05 Sist oppdatert: 2017-12-07bibliografisk kontrollert
    3. Synthesis and polymerization of alkyl halide-functional cyclic carbonates
    Åpne denne publikasjonen i ny fane eller vindu >>Synthesis and polymerization of alkyl halide-functional cyclic carbonates
    2011 (engelsk)Inngår i: Polymer, ISSN 0032-3861, E-ISSN 1873-2291, Vol. 52, nr 25, s. 5716-5722Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    To increase the diversity in functional aliphatic polycarbonates, a series of novel chloro- and bromo-functional six-membered cyclic carbonate monomers were synthesized. Despite asymmetry in the monomer functionalities, homopolymerization of the monomers afforded semicrystalline polycarbonates with a high tendency to crystallize from the melt and/or on precipitation from a THF solution. Melting points were found in the 90-105 degrees C or 120-155 degrees C range for polymers comprising methyl or ethyl moieties, respectively, in the backbone. The monomers were further copolymerized with trimethylene carbonate to form random copolymers. Even among some of these random copolymers elements of semicrystallinity were found as confirmed by melting endotherms in DSC. The results clearly show that the incorporation of alkyl halide functionalities in aliphatic polycarbonates may lead to materials with a high ability to form crystallites, even in random copolymers, likely driven by polar interactions due to the presence of the halide functionalities.

    Emneord
    Cyclic carbonate monomers, Polycarbonates, Semicrystalline polymers
    HSV kategori
    Forskningsprogram
    Kemi med inriktning mot polymerkemi
    Identifikatorer
    urn:nbn:se:uu:diva-165694 (URN)10.1016/j.polymer.2011.10.027 (DOI)000297539000004 ()
    Tilgjengelig fra: 2012-01-10 Laget: 2012-01-09 Sist oppdatert: 2017-12-08bibliografisk kontrollert
    4. Diversity in cyclic carbonates: Synthesis of triazole-functional monomers using click chemistry
    Åpne denne publikasjonen i ny fane eller vindu >>Diversity in cyclic carbonates: Synthesis of triazole-functional monomers using click chemistry
    2012 (engelsk)Inngår i: Polymer Chemistry, ISSN 1759-9962, Vol. 3, nr 6, s. 1399-1401Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Triazole-functional cyclic carbonates are presented as a new class of functional monomers for ring-opening polymerisation. Starting from bromo-functional six-membered cyclic carbonates, a series of triazole-functional monomers was synthesised using click chemistry. This synthetic strategy allows for facile synthesis of a great number of structurally diverse monomers from just a few azide-functional precursors.

    sted, utgiver, år, opplag, sider
    Royal Society of Chemistry, 2012
    HSV kategori
    Forskningsprogram
    Kemi med inriktning mot polymerkemi
    Identifikatorer
    urn:nbn:se:uu:diva-169676 (URN)10.1039/C2PY20152F (DOI)000303773600005 ()
    Tilgjengelig fra: 2012-03-13 Laget: 2012-03-05 Sist oppdatert: 2013-01-08bibliografisk kontrollert
  • 88.
    Mindemark, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Bowden, Tim
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Diversity in cyclic carbonates: Synthesis of triazole-functional monomers using click chemistry2012Inngår i: Polymer Chemistry, ISSN 1759-9962, Vol. 3, nr 6, s. 1399-1401Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Triazole-functional cyclic carbonates are presented as a new class of functional monomers for ring-opening polymerisation. Starting from bromo-functional six-membered cyclic carbonates, a series of triazole-functional monomers was synthesised using click chemistry. This synthetic strategy allows for facile synthesis of a great number of structurally diverse monomers from just a few azide-functional precursors.

  • 89.
    Mindemark, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Bowden, Tim
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Efficient DNA Binding and Condensation Using Low Molecular Weight, Low Charge Density Cationic Polymer Amphiphiles2010Inngår i: Macromolecular rapid communications, ISSN 1022-1336, E-ISSN 1521-3927, Vol. 31, nr 15, s. 1378-1382Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A new class of biodegradable cationic macromolecules for DNA binding and condensation was developed by end-group-functionalization of poly(trimethylene carbonate). A series of one- and two-armed structures was synthesized and their interaction with DNA was evaluated. To aid data interpretation, a non-linear modeling method was applied to show efficient DNA binding that was intimately related to cationic charge density and macromolecular architecture. One-armed, low charge density structures were consistently found to bind to DNA at lower charge ratios than their two-armed, high charge density counterparts. This suggests that polymer backbone structure and characteristics are important considerations in the development of efficient cationic polymer systems for DNA condensation and delivery.

  • 90.
    Mindemark, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Bowden, Tim
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Low molecular weight, low charge density cationic polymers for gene delivery2009Inngår i: Frontiers in Polymer Science, Mainz, Tyskland 7–9 juni 2009, 2009Konferansepaper (Fagfellevurdert)
  • 91.
    Mindemark, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Bowden, Tim
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Novel Alkyl Halide-functional Polycarbonates and the Synthesis of Functional Cyclic Carbonate Monomers using Click Chemistry2011Konferansepaper (Fagfellevurdert)
  • 92.
    Mindemark, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Bowden, Tim
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi, Polymerkemi.
    Synthesis and polymerization of alkyl halide-functional cyclic carbonates2011Inngår i: Polymer, ISSN 0032-3861, E-ISSN 1873-2291, Vol. 52, nr 25, s. 5716-5722Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To increase the diversity in functional aliphatic polycarbonates, a series of novel chloro- and bromo-functional six-membered cyclic carbonate monomers were synthesized. Despite asymmetry in the monomer functionalities, homopolymerization of the monomers afforded semicrystalline polycarbonates with a high tendency to crystallize from the melt and/or on precipitation from a THF solution. Melting points were found in the 90-105 degrees C or 120-155 degrees C range for polymers comprising methyl or ethyl moieties, respectively, in the backbone. The monomers were further copolymerized with trimethylene carbonate to form random copolymers. Even among some of these random copolymers elements of semicrystallinity were found as confirmed by melting endotherms in DSC. The results clearly show that the incorporation of alkyl halide functionalities in aliphatic polycarbonates may lead to materials with a high ability to form crystallites, even in random copolymers, likely driven by polar interactions due to the presence of the halide functionalities.

  • 93.
    Mindemark, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Sobkowiak, Adam
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Oltean, Gabriel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Brandell, Daniel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Gustafsson, Torbjörn
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Mechanical Stabilization of Solid Polymer Electrolytes through Gamma Irradiation2016Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Recent research efforts into solid polymer electrolytes (SPEs) beyond the polyether paradigm have broadened the research field with new materials that offer improvements in performance as well as opportunities for tailoring materials for specific applications. In particular materials based on polycarbonates and polyesters have shown to fulfil this promise, as shown for systems based on both the poly(ethylene carbonate) [1,2] and the poly(trimethylene carbonate) [3,4] backbone structures. This has ultimately led to the development of SPEs that can be used in Li batteries operational at room temperature. [1,4]

     

    Since ion conduction in these materials – at least at moderate salt concentrations – is coupled to the polymer chain dynamics, the performance of these electrolytes is inherently a compromise between mechanics and ion dynamics. While this is not necessarily an issue at room temperature, it becomes notable at elevated temperatures and we have observed migration of the electrolyte during long-term battery operation under such conditions, ultimately leading to failure of the electrolyte membrane to act as a separator between the electrodes with concomitant battery failure.

     

    A solution to this is to chemically crosslink the material in order to stabilize it mechanically. For the poly(ε-caprolactone-co-trimethylene carbonate) host material we have already successfully used in high-performance Li battery cells, [4] this can be done through γ-irradiation. [5] Here, we have explored this treatment in the context of SPEs and show the effects of γ-irradiation on the mechanical properties, ionic conductivity and battery cell performance at room temperature and beyond.

     

     

    Figure 1. Viscoelastic properties (left) and ionic conductivity (right) of pristine and γ-irradiated SPEs.

     

    References

    [1] K. Kimura, M. Yajima, Y. Tominaga, Electrochem. Commun. 66 (2016) 46-48.

    [2] M. D. Konieczynska, X. Lin, H. Zhang, M. W. Grinstaff, ACS Macro Lett. 4 (2015) 533-537.

    [3] J. Mindemark, B. Sun, D. Brandell, Polym. Chem. 6 (2015) 4766-4774.

    [4] J. Mindemark, B. Sun, E. Törmä, D. Brandell, J. Power Sources 298 (2015) 166-170.

    [5]                        E. Bat, J. A. Plantinga, M. C. Harmsen, M. J. A. van Luyn, Z. Zhang, D. W. Grijpma, J. Feijen, Biomacromolecules 9 (2008) 3208–3215

  • 94.
    Mindemark, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Sun, Bing
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Brandell, Daniel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Aliphatic Polycarbonates as Solid State Electrolytes for Lithium Ion Batteries2013Konferansepaper (Fagfellevurdert)
    Abstract
  • 95.
    Mindemark, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Sun, Bing
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Brandell, Daniel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Development of functional polycarbonate-based electrolytes for lithium-ion batteries2014Konferansepaper (Fagfellevurdert)
    Abstract
  • 96.
    Mindemark, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Sun, Bing
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Brandell, Daniel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Long-term stability of polycarbonate-based solid polymer electrolytes: 1-year anniversary of the first PTMC Li-ion cel2013Konferansepaper (Fagfellevurdert)
    Abstract
  • 97.
    Mindemark, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Tabata, Yasuhiko
    Department of Biomaterials, Institute for Frontier Medical Sciences, Kyoto University.
    Bowden, Tim
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Polymerkemi.
    Low Charge Density Cationic Polymers for Gene Delivery: Exploring the Influence of Structural Elements on In Vitro Transfection2012Inngår i: Macromolecular Bioscience, ISSN 1616-5187, E-ISSN 1616-5195, Vol. 12, nr 6, s. 840-848Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A series of end-functionalized poly(trimethylene carbonate) DNA carriers, characterized by low cationic charge density and pronounced hydrophobicity, was used to study structural effects on in vitro gene delivery. As the DNA-binding moieties were identical in all polymer structures, the differences observed between the different polymers were directly related to the functionality and length of the polymer backbone. The transfection efficiency and cytotoxicity of the polymer/DNA complexes were thus found to be dependent on a combination of polymer charge density and functionality, highlighting the importance of such structural considerations in the development of materials for efficient gene delivery.

  • 98.
    Mindemark, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Tang, Shi
    Umeå universitet.
    Brandell, Daniel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Edman, Ludvig
    Umeå universitet.
    Improving the Performance of Light-Emitting Electrochemical Cells through Electrolyte End-Group Modification2014Konferansepaper (Fagfellevurdert)
    Abstract
  • 99.
    Mindemark, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Tang, Shi
    Li, Hu
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Edman, Ludvig
    Electrolytes for High-Brightness, High-Efficiency Light-Emitting Electrochemical Cells: Going from Polymers to Oligomers2017Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The light-emitting electrochemical cell (LEC), comprising, e.g., a conjugated light-emitting polymer in combination with an electrolyte, offers a promise of cheap and versatile light emission in a simple single-layer device with little dependence on active layer geometry or electrode work functions [1]. The defining feature of the LEC is the presence of mobile ions in the active layer that enables in situ electrochemical doping and p-n junction formation, which gives the LEC a unique set of operational features that distinguishes it from, e.g., the OLED. This includes ion transport-limited turn-on kinetics [2] and an apparent trade-off between brightness and efficiency [3].

    The mobile ions in an LEC may be provided by means of a polymer electrolyte, i.e., a salt solvated by a polymeric ion transporter, most typically the polyether PEO [2]. Here, we build upon our previous work on high-performance oligoether ion transporters [4] and explore ion transporters based on polycarbonate backbones. Using properly designed molecular structures, we demonstrate record-high current efficacy combined with long operational lifetimes and, most importantly, high-brightness operation. We further reveal distinct differences between polymeric and oligomeric ion transporters in terms of ion transport and phase compatibility and demonstrate how this affects the turn-on kinetics and device efficiency, paving the way for designing new generations of ion transporters for high-performance LECs using ion transporters beyond the polyether paradigm.

    References

    1. (a) Fresta, E.; Costa, R. D. J. Mater. Chem. C 2017, 5, 5643–5675; (b) Tang, S.; Edman, L. Top. Curr. Chem. 2016, 374, 40.
    2. Mindemark, J.; Edman, L. J. Mater. Chem. C 2016, 4, 420–432.
    3. van Reenen, S. et al. Adv. Funct. Mater. 2015, 25, 3066–3073.
    4. Mindemark, J. et al. Chem. Mater. 2016, 28, 2618–2623.
  • 100.
    Mindemark, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi. Umea Univ, Dept Phys, Organ Photon & Elect Grp, SE-90187 Umea, Sweden..
    Tang, Shi
    Umea Univ, Dept Phys, Organ Photon & Elect Grp, SE-90187 Umea, Sweden.;LunaLEC AB, Tvistevagen 47, SE-90719 Umea, Sweden..
    Li, Hu
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Tillämpad materialvetenskap.
    Edman, Ludvig
    Umea Univ, Dept Phys, Organ Photon & Elect Grp, SE-90187 Umea, Sweden.;LunaLEC AB, Tvistevagen 47, SE-90719 Umea, Sweden..
    Ion Transport beyond the Polyether Paradigm: Introducing Oligocarbonate Ion Transporters for Efficient Light-Emitting Electrochemical Cells2018Inngår i: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 28, nr 32, artikkel-id 1801295Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The light-emitting electrochemical cell (LEC) is fundamentally dependent on mobile ions for its operation. In polymer LECs, the mobile ions are commonly provided by dissolving a salt in an ion transporter, with the latter almost invariably being an ether-based compound. Here, the synthesis, characterization, and application of a new class of carbonate-based ion transporters are reported. A polymer LEC, comprising a star-branched oligocarbonate endowed with aliphatic side groups as the ion transporter, features a current efficacy of 13.8 cd A(-1) at a luminance of 1060 cd m(-2), which is a record-high efficiency/luminance combination for a singlet-emitting LEC. It is further established that the design principles of a high-performance carbonate ion transporter constitute the selection of an oligomeric structure over a corresponding polymeric structure and the endowment of the oligomer with functional side chains to render it compatible with the polymeric emitter.

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