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Ferraz, Natalia
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Publications (10 of 69) Show all publications
Tummala, G. K., Lopes, V., Mihranyan, A. & Ferraz, N. (2019). Biocompatibility of nanocellulose-reinforced PVA hydrogel with human corneal epithelial cells for Ophthalmic applications. Journal of Functional Biomaterials, 10(3), Article ID 35.
Open this publication in new window or tab >>Biocompatibility of nanocellulose-reinforced PVA hydrogel with human corneal epithelial cells for Ophthalmic applications
2019 (English)In: Journal of Functional Biomaterials, ISSN 2079-4983, E-ISSN 2079-4983, Vol. 10, no 3, article id 35Article in journal (Refereed) Published
Abstract [en]

Transparent composite hydrogel in the form of a contact lens made from poly(vinyl alcohol) (PVA) and cellulose nanocrystals (CNCs) was subjected to in vitro biocompatibility evaluation with human corneal epithelial cells (HCE-2 cells). The cell response to direct contact with the hydrogels was investigated by placing the samples on top of confluent cell layers and evaluating cell viability, morphology, and cell layer integrity subsequent to 24 h culture and removal of the hydrogels. To further characterize the lens-cell interactions, HCE-2 cells were seeded on the hydrogels, with and without simulated tear fluid (STF) pre-conditioning, and cell viability and morphology were evaluated. Furthermore, protein adsorption on the hydrogel surface was investigated by incubating the materials with STF, followed by protein elution and quantification. The hydrogel material was found to have affinity towards protein adsorption, most probably due to the interactions between the positively charged lysozyme and the negatively charged CNCs embedded in the PVA matrix. The direct contact experiment demonstrated that the physical presence of the lenses did not affect corneal epithelial cell monolayers in terms of integrity nor cell metabolic activity. Moreover, it was found that viable corneal cells adhered to the hydrogel, showing the typical morphology of epithelial cells and that such response was not influenced by the STF pre-conditioning of the hydrogel surface. The results of the study confirm that PVA-CNC hydrogel is a promising ophthalmic biomaterial, motivating future in vitro and in vivo biocompatibility studies.

National Category
Nano Technology
Research subject
Engineering Science with specialization in Nanotechnology and Functional Materials
Identifiers
urn:nbn:se:uu:diva-343806 (URN)10.3390/jfb10030035 (DOI)000487948900010 ()31375008 (PubMedID)
Funder
Knut and Alice Wallenberg Foundation, 2013.0190
Available from: 2018-03-01 Created: 2018-03-01 Last updated: 2019-10-25Bibliographically approved
Rocha, I., Lindh, J., Hong, J., Strömme, M., Mihranyan, A. & Ferraz, N. (2018). Blood Compatibility of Sulfonated Cladophora Nanocellulose Beads. Molecules, 23(3), Article ID 601.
Open this publication in new window or tab >>Blood Compatibility of Sulfonated Cladophora Nanocellulose Beads
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2018 (English)In: Molecules, ISSN 1420-3049, E-ISSN 1420-3049, Vol. 23, no 3, article id 601Article in journal (Refereed) Published
Abstract [en]

Sulfonated cellulose beads were prepared by oxidation of Cladophora nanocellulose to 2,3-dialdehyde cellulose followed by sulfonation using bisulfite. The physicochemical properties of the sulfonated beads, i.e., high surface area, high degree of oxidation, spherical shape, and the possibility of tailoring the porosity, make them interesting candidates for the development of immunosorbent platforms, including their application in extracorporeal blood treatments. A desired property for materials used in such applications is blood compatibility; therefore in the present work, we investigate the hemocompatibility of the sulfonated cellulose beads using an in vitro whole blood model. Complement system activation (C3a and sC5b-9 levels), coagulation activation (thrombin-antithrombin (TAT) levels) and hemolysis were evaluated after whole blood contact with the sulfonated beads and the results were compared with the values obtained with the unmodified Cladophora nanocellulose. Results showed that neither of the cellulosic materials presented hemolytic activity. A marked decrease in TAT levels was observed after blood contact with the sulfonated beads, compared with Cladophora nanocellulose. However, the chemical modification did not promote an improvement in Cladophora nanocellulose hemocompatibility in terms of complement system activation. Even though the sulfonated beads presented a significant reduction in pro-coagulant activity compared with the unmodified material, further modification strategies need to be investigated to control the complement activation by the cellulosic materials.

Keywords
sulfonated beads; Cladophora nanocellulose; hemocompatibility; coagulation; complement system
National Category
Nano Technology
Identifiers
urn:nbn:se:uu:diva-346209 (URN)10.3390/molecules23030601 (DOI)000428514100092 ()
Funder
Knut and Alice Wallenberg Foundation
Available from: 2018-03-15 Created: 2018-03-15 Last updated: 2019-06-28Bibliographically approved
Park, M. V. D., Catalan, J., Ferraz, N., Cabellos, J., Vanhauten, R., Vazquez-Campos, S. & Janer, G. (2018). Development of a systematic method to assess similarity between nanomaterials for human hazard evaluation purposes - lessons learnt. Nanotoxicology, 12(7), 652-676
Open this publication in new window or tab >>Development of a systematic method to assess similarity between nanomaterials for human hazard evaluation purposes - lessons learnt
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2018 (English)In: Nanotoxicology, ISSN 1743-5390, E-ISSN 1743-5404, Vol. 12, no 7, p. 652-676Article in journal (Refereed) Published
Abstract [en]

Within the EU FP-7 GUIDEnano project, a methodology was developed to systematically quantify the similarity between a nanomaterial (NM) that has been tested in toxicity studies and the NM for which risk needs to be evaluated, for the purpose of extrapolating toxicity data between the two materials. The methodology is a first attempt to use current knowledge on NM property-hazard relationships to develop a series of pragmatic and systematic rules for assessing NM similarity. Moreover, the methodology takes into account the practical feasibility, in that it is based on generally available NM characterization information. In addition to presenting this methodology, the lessons learnt and the challenges faced during its development are reported here. We conclude that there is a large gap between the information that is ideally needed and its application to real cases. The current database on property-hazard relationships is still very limited, which hinders the agreement on the key NM properties constituting the basis of the similarity assessment and the development of associated science-based and unequivocal rules. Currently, one of the most challenging NM properties to systematically assess in terms of similarity between two NMs is surface coating and functionalization, which lacks standardized parameters for description and characterization methodology. Standardization of characterization methods that lead to quantitative, unambiguous, and measurable parameters describing NM properties are necessary in order to build a sufficiently robust property-hazard database that allows for evidence-based refinement of our methodology, or any other attempt to systematically assess the similarity of NMs.

Place, publisher, year, edition, pages
TAYLOR & FRANCIS LTD, 2018
Keywords
Similarity, nanomaterials, toxicity, size, shape, surface chemistry, physicochemical properties, nanoforms, read-across, risk assessment
National Category
Environmental Sciences Engineering and Technology
Identifiers
urn:nbn:se:uu:diva-364487 (URN)10.1080/17435390.2018.1465142 (DOI)000443905400001 ()29732939 (PubMedID)
Funder
EU, FP7, Seventh Framework Programme, 604387
Available from: 2018-10-29 Created: 2018-10-29 Last updated: 2018-11-01Bibliographically approved
Rocha, I., Ferraz, N., Mihranyan, A., Strömme, M. & Lindh, J. (2018). Hemocompatibility of porous sulfonated Cladophora cellulose beads towards a blood purification material with anticoagulant properties. Paper presented at 255th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nexus of Food, Energy, and Water, MAR 18-22, 2018, New Orleans, LA, USA. Abstract of Papers of the American Chemical Society, 255
Open this publication in new window or tab >>Hemocompatibility of porous sulfonated Cladophora cellulose beads towards a blood purification material with anticoagulant properties
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2018 (English)In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 255Article in journal, Meeting abstract (Other academic) Published
Place, publisher, year, edition, pages
AMER CHEMICAL SOC, 2018
National Category
Nano Technology
Research subject
Engineering Science with specialization in Nanotechnology and Functional Materials
Identifiers
urn:nbn:se:uu:diva-365865 (URN)000435537703062 ()
Conference
255th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nexus of Food, Energy, and Water, MAR 18-22, 2018, New Orleans, LA, USA
Available from: 2018-11-20 Created: 2018-11-20 Last updated: 2018-11-20Bibliographically approved
Basu, A., Celma, G., Strömme, M. & Ferraz, N. (2018). In Vitro and in Vivo Evaluation of the Wound Healing Properties of Nanofibrillated Cellulose Hydrogels. ACS Applied Bio Materials
Open this publication in new window or tab >>In Vitro and in Vivo Evaluation of the Wound Healing Properties of Nanofibrillated Cellulose Hydrogels
2018 (English)In: ACS Applied Bio MaterialsArticle in journal (Refereed) Published
Abstract [en]

Current trends in wound care research move toward the development of wound healing dressings designed to treat different types of wounds (e.g., burns and chronic wounds) and toward tailoring treatments for different stages of the wound healing process. In this context, the development of advanced nanotherapeutic materials is highlighted as a promising strategy to efficiently control specific phases of the wound healing process. Here, Ca2+-cross-linked wood-derived nanofibrillated cellulose (NFC) hydrogels are evaluated as wound healing dressings. In vitro biocompatibility assays were performed to study the interaction of the NFC hydrogels with cellular processes that are tightly related to wound healing. Moreover, an in vivo dermo-epidermic full thickness wound healing model in rat was used to uncover the wound healing ability of the Ca2+-cross-linked NFC hydrogels. The in vitro experiments showed that the NFC hydrogels were able to support fibroblast and keratinocyte proliferation. A potential effect of the hydrogels on triggering keratinocyte differentiation was furthermore proposed. In vivo, the NFC hydrogels stimulated healing without causing any adverse local tissue effects, potentially owing to their moisture-donating properties and the herein discussed aiding effect of the Ca2+-cross-linker on epidermal generation. Thus, this work extensively demonstrates the wound healing ability of NFC hydrogels and presents an important milestone in the research on NFC toward advanced wound healing applications.

Place, publisher, year, edition, pages
American Chemical Society, 2018
National Category
Other Materials Engineering Medical Materials
Research subject
Engineering Science with specialization in Nanotechnology and Functional Materials
Identifiers
urn:nbn:se:uu:diva-366555 (URN)10.1021/acsabm.8b00370 (DOI)
Available from: 2018-11-21 Created: 2018-11-21 Last updated: 2019-02-06Bibliographically approved
Basu, A., Heitz, K., Strömme, M., Welch, K. & Ferraz, N. (2018). Ion-crosslinked wood-derived nanocellulose hydrogels with tunable antibacterial properties: Candidate materials for advanced wound care applications. Carbohydrate Polymers, 181, 345-350
Open this publication in new window or tab >>Ion-crosslinked wood-derived nanocellulose hydrogels with tunable antibacterial properties: Candidate materials for advanced wound care applications
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2018 (English)In: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 181, p. 345-350Article in journal (Refereed) Published
Abstract [en]

Development of advanced dressings with antimicrobial properties for the treatment of infected wounds is an important approach in the fight against evolution of antibiotic resistant bacterial strains. Herein, the effects of ion-crosslinked nanocellulose hydrogels on bacteria commonly found in infected wounds were investigated in vitro. By using divalent calcium or copper ions as crosslinking agents, different antibacterial properties against the bacterial strains Staphylococcus epidermidis and Pseudomonas aeruginosa were obtained. Calcium crosslinked hydrogels were found to retard S. epidermidis growth (up to 266% increase in lag time, 36% increase in doubling time) and inhibited P. aeruginosa biofilm formation, while copper crosslinked hydrogels prevented S. epidermidis growth and were bacteriostatic towards P. aeruginosa (49% increase in lag time, 78% increase in doubling time). The wound dressing candidates furthermore displayed barrier properties towards both S. epidermidis and P. aeruginosa, hence making them interesting for further development of advanced wound dressings with tunable antibacterial properties.

Keywords
Nanofibrillated cellulose, Biofilm, Wound dressing, Infected wound
National Category
Nano Technology
Research subject
Engineering Science with specialization in Nanotechnology and Functional Materials
Identifiers
urn:nbn:se:uu:diva-333382 (URN)10.1016/j.carbpol.2017.10.085 (DOI)000418661000041 ()29253982 (PubMedID)
Funder
Swedish Research Council Formas
Available from: 2017-11-13 Created: 2017-11-13 Last updated: 2018-10-12Bibliographically approved
Ferraz, N. (2018). Nanocellulose for biomedical applications. In: Uppsala Biomaterials and Bioengineering Meeting September 4th, 2018.: . Paper presented at Uppsala Biomaterials and Bioengineering Meeting September 4th, 2018. Uppsala, Sweden.
Open this publication in new window or tab >>Nanocellulose for biomedical applications
2018 (English)In: Uppsala Biomaterials and Bioengineering Meeting September 4th, 2018., 2018Conference paper, Oral presentation with published abstract (Refereed)
National Category
Medical Materials Other Materials Engineering
Research subject
Engineering Science with specialization in Nanotechnology and Functional Materials
Identifiers
urn:nbn:se:uu:diva-366850 (URN)
Conference
Uppsala Biomaterials and Bioengineering Meeting September 4th, 2018. Uppsala, Sweden
Available from: 2018-11-26 Created: 2018-11-26 Last updated: 2019-03-13Bibliographically approved
Fernandez-Cruz, M. L., Hernandez-Moreno, D., Catalan, J., Cross, R., Stockmann-Juvala, H., Cabellos, J., . . . Janer, G. (2018). Quality evaluation of human and environmental toxicity studies performed with nanomaterials – the GUIDEnano approach. Environmental Science: Nano, 5(2), 381-397
Open this publication in new window or tab >>Quality evaluation of human and environmental toxicity studies performed with nanomaterials – the GUIDEnano approach
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2018 (English)In: Environmental Science: Nano, Vol. 5, no 2, p. 381-397Article in journal (Refereed) Published
Abstract [en]

The European Union FP-7 project GUIDEnano developed a web-based guidance tool, which guides users to assess human and environmental risks of nanomaterial-enabled products throughout their life cycle. One of the aims in the GUIDEnano hazard assessment strategy is to derive safety limit values based on existing human toxicity and ecotoxicological studies. Clear criteria needed to be established to select studies that could be used for such purpose. In the present paper, we present an approach for a systematical and quantitative evaluation of the quality of environmental and human toxicity studies performed with nanomaterials. The approach builds upon previous initiatives and includes refinements to facilitate its application by users with limited toxicological expertise. It covers in vivo and in vitro human toxicity studies as well as ecotoxicological studies addressing the toxicity to all environmental compartments. A scoring system related to test design and reporting considerations was developed following the principles of the Klimisch score (K score). In addition, the approach includes a scoring system based on the physicochemical properties that have been characterized and reported for the nanomaterial, including properties characterized in the exposure medium (S score). These two scores (K and S) are combined to obtain an overall quality score (Q score) that can be used to select studies, to weight different studies, and/or to introduce uncertainty factors in the risk assessment process. During its development, the approach has been tested and refined with 137 peer-reviewed articles. The final quality assessment approach and the results of its evaluation are presented here.

Keywords
quality, toxicity, ecotoxicity, nanomaterial, reliability, data completeness
National Category
Nano Technology Environmental Sciences
Research subject
Engineering Science with specialization in Nanotechnology and Functional Materials
Identifiers
urn:nbn:se:uu:diva-335733 (URN)10.1039/C7EN00716G (DOI)000425492800013 ()
Funder
EU, FP7, Seventh Framework Programme, 604387 GUIDEnano
Available from: 2017-12-07 Created: 2017-12-07 Last updated: 2018-05-07Bibliographically approved
Rocha, I., Ferraz, N., Mihranyan, A., Strömme, M. & Lindh, J. (2018). Sulfonated Nanocellulose Beads as Potential Immunosorbents. Cellulose (London), 28(3), 1899-1910
Open this publication in new window or tab >>Sulfonated Nanocellulose Beads as Potential Immunosorbents
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2018 (English)In: Cellulose (London), ISSN 0969-0239, E-ISSN 1572-882X, Vol. 28, no 3, p. 1899-1910Article in journal (Refereed) Published
Abstract [en]

Herein 2,3-dialdehyde cellulose beads prepared from Cladophora green algae nanocellulose were sulfonated and characterized by FTIR, conductometric titration, elemental analysis, SEM, ζ-potential, nitrogen adsorption–desorption and laser diffraction, aiming for its application as a potential immunosorbent material. Porous beads were prepared at mild reaction conditions in water and were chemically modified by sulfonation and reduction. The obtained 15 µm sized sulfonated beads were found to be highly charged and to have a high surface area of ~ 100 m2 g−1 and pore sizes between 20 and 60 nm, adequate for usage as immunosorbents. After reduction of remaining aldehyde groups, the beads could be classified as non-cytotoxic in indirect toxicity studies with human dermal fibroblasts as a first screening of their biocompatibility. The observed properties make the sulfonated cellulose beads interesting for further development as matrix material in immunosorbent devices.

Keywords
Periodate oxidation Dialdehyde cellulose, Surface group density, Sulfonated beads, Cytotoxicity
National Category
Nano Technology
Identifiers
urn:nbn:se:uu:diva-346207 (URN)10.1007/s10570-018-1661-2 (DOI)000427379200027 ()
Funder
Knut and Alice Wallenberg Foundation
Available from: 2018-03-15 Created: 2018-03-15 Last updated: 2018-05-18Bibliographically approved
Basu, A., Strömme, M. & Ferraz, N. (2018). Towards Tunable Protein-Carrier Wound Dressings Based on Nanocellulose Hydrogels Crosslinked with Calcium Ions. Nanomaterials, 8(7), Article ID 550.
Open this publication in new window or tab >>Towards Tunable Protein-Carrier Wound Dressings Based on Nanocellulose Hydrogels Crosslinked with Calcium Ions
2018 (English)In: Nanomaterials, E-ISSN 2079-4991, Vol. 8, no 7, article id 550Article in journal (Refereed) Published
Abstract [en]

A Ca2+-crosslinked wood-based nanofibrillated cellulose (NFC) hydrogel was investigated to build knowledge toward the use of nanocellulose for topical drug delivery applications in a chronic wound healing context. Proteins of varying size and isoelectric point were loaded into the hydrogel in a simple soaking procedure. The release of the proteins from the hydrogel was monitored and kinetics determining parameters of the release processes were assessed. The integrity of the hydrogel and proteins were also studied. The results showed that electrostatic interactions between the proteins and the negatively-charged NFC hydrogel structure played a central role in the loading process. The release of the proteins were governed by Fickian diffusion. An increased protein size, as well as a positive protein charge facilitated a slower and more sustained release process from the hydrogel matrix. At the same time, the positively-charged protein was shown to increase the post-loading hydrogel strength. Released proteins maintained structural stability and activity, thus indicating that the Ca2+-crosslinked NFC hydrogel could function as a carrier of therapeutic proteins without compromising protein function. It is foreseen that, by utilizing tunable charge properties of the NFC hydrogel, release profiles can be tailored to meet very specific treatment needs.

Place, publisher, year, edition, pages
MDPI, 2018
Keywords
nanofibrillated cellulose, ion-crosslinked, drug delivery, wound healing, chronic wounds
National Category
Nano Technology
Research subject
Engineering Science with specialization in Nanotechnology and Functional Materials
Identifiers
urn:nbn:se:uu:diva-362722 (URN)10.3390/nano8070550 (DOI)000442523100101 ()30036970 (PubMedID)
Funder
Swedish Research Council Formas, 942-2015-475
Available from: 2018-10-09 Created: 2018-10-09 Last updated: 2018-10-30Bibliographically approved
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