This article was downloaded by: [University of Kent] On: 14 December 2014, At: 09:45 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK
Journal of Biomaterials Science, Polymer Edition Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/tbsp20
Fabrication and characterization of chitosan–collagen crosslinked membranes for corneal tissue engineering a
a
a
a
a
Weichang Li , Yuyu Long , Yang Liu , Kai Long , Sa Liu , Zhichong b
a
Wang , Yingjun Wang & Li Ren
a
a
School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641, P.R. China b
State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou 510060, P.R. China Published online: 09 Oct 2014.
To cite this article: Weichang Li, Yuyu Long, Yang Liu, Kai Long, Sa Liu, Zhichong Wang, Yingjun Wang & Li Ren (2014) Fabrication and characterization of chitosan–collagen crosslinked membranes for corneal tissue engineering, Journal of Biomaterials Science, Polymer Edition, 25:17, 1962-1972, DOI: 10.1080/09205063.2014.965996 To link to this article: http://dx.doi.org/10.1080/09205063.2014.965996
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing,
Downloaded by [University of Kent] at 09:45 14 December 2014
systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/termsand-conditions
Journal of Biomaterials Science, Polymer Edition, 2014 Vol. 25, No. 17, 1962–1972, http://dx.doi.org/10.1080/09205063.2014.965996
Fabrication and characterization of chitosan–collagen crosslinked membranes for corneal tissue engineering Weichang Lia, Yuyu Longa, Yang Liua, Kai Longa, Sa Liua, Zhichong Wangb, Yingjun Wanga and Li Rena*
Downloaded by [University of Kent] at 09:45 14 December 2014
a School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641, P.R. China; bState Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou 510060, P.R. China
(Received 19 April 2014; accepted 10 September 2014) This article describes a chitosan–collagen composite membrane as corneal tissueengineering biomaterials. The membrane was prepared by dissolving the chitosan into collagen with the weight ratio of 0, 15, 30, 45, 60, and 100%, followed by crosslinked with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide. Mechanical properties, contact angles, and optical transmittance were determined and compared between chitosan membrane and crosslinking composite membrane. As a result, the optical transparency and mechanical strength of the chitosan–collagen membranes were significantly better than that of the sample of chitosan. In addition, in vitro cell culture studies revealed that the collagen has no negative effect on the cell morphology, viability, and proliferation and possess good biocompatibility. Overall, the dendrimer crosslinked chitosan–collagen composite membranes showed promising properties that suggest that these might be suitable biomaterials for corneal tissueengineering applications. Keywords: 1-ethyl-3-(3-dimethylaminopropyl) collagen; crosslinked membranes
carbodiimide
(EDC);
chitosan;
1. Introduction The cornea, which is the transparent, avascular, surface layer of the eye, could protect the intraocular tissues. Approximately, 285 million people worldwide are suffering from impaired vision; of these, 2.85 million have corneal opacities.[1] Allograft cornea transplantation is an effective method to resolve this disease. However, there are some limiting factors, such as the shortage of donor corneas, the rejection to the donor grafts in many patients and unprofessional skills for corneal grafting in some underdeveloped countries.[2] Tissue-engineering technology provides a new way to cure the corneal diseases, and the preparation of an ideal corneal tissue-engineering scaffold plays a key role. An ideal corneal scaffold material should not only have good biocompatibility and controllable degradability, but also have suitable optical transmittance and mechanical properties. In recent years, different corneal substitutes have been developed by using amniotic membrane,[3–5] chitosan,[6] fibrin,[7,8] caprolactone,[9] collagen hydrogel,[10] and other biomaterials. Although these corneal grafts exhibit good biocompatibility, the microstructure of the natural cornea is not imitated completely. *Corresponding author. Email: [email protected] © 2014 Taylor & Francis
Downloaded by [University of Kent] at 09:45 14 December 2014
Journal of Biomaterials Science, Polymer Edition
1963
So researchers are still developing new materials with optimal structures for clinic corneal transplantation. Among these materials, chitosan is a linear polysaccharide consisting of randomly distributed glucosamine and N-acetylglucosamine repeat units, and is derived from N-deacetylation of chitin.[11] Important properties of chitosan are biocompatible, biodegradable, and nontoxic nature, making this polymer suitable for extensively investigated as a material for various tissue-engineering applications.[12,13] Chitosan membrane is easily prepared due to its physicochemical properties, such as permeability, tensile strength, and adhesion property.[14] However, inherent water sensitivity and relatively low-stability properties still limit the use of chitosan membranes for a wider range of applications, especially in moist environments.[15] Many materials have been used to improve the chitosan membrane, such as nanowhiskers,[15] poly(vinyl alcohol),[16] or collagen.[14] Among these materials, collagen was focused by researchers as it is one of the main components of extracellular matrix, and is well known for excellent biocompatibility, low antigenicity, and biodegradability. In this study, we developed a biomimic corneal material containing chitosan and collagen crosslinked with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC). We then employed scanning electron microscope (SEM) and PC spectrophotometer to characterize the materials, and reported their biocompatibility with human corneal epithelial cells. 2. Materials and methods 2.1. Materials Chitosan (degree of deacetylation ≥90%, viscosity
Journal of Biomaterials Science, Polymer Edition Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/tbsp20
Fabrication and characterization of chitosan–collagen crosslinked membranes for corneal tissue engineering a
a
a
a
a
Weichang Li , Yuyu Long , Yang Liu , Kai Long , Sa Liu , Zhichong b
a
Wang , Yingjun Wang & Li Ren
a
a
School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641, P.R. China b
State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou 510060, P.R. China Published online: 09 Oct 2014.
To cite this article: Weichang Li, Yuyu Long, Yang Liu, Kai Long, Sa Liu, Zhichong Wang, Yingjun Wang & Li Ren (2014) Fabrication and characterization of chitosan–collagen crosslinked membranes for corneal tissue engineering, Journal of Biomaterials Science, Polymer Edition, 25:17, 1962-1972, DOI: 10.1080/09205063.2014.965996 To link to this article: http://dx.doi.org/10.1080/09205063.2014.965996
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing,
Downloaded by [University of Kent] at 09:45 14 December 2014
systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/termsand-conditions
Journal of Biomaterials Science, Polymer Edition, 2014 Vol. 25, No. 17, 1962–1972, http://dx.doi.org/10.1080/09205063.2014.965996
Fabrication and characterization of chitosan–collagen crosslinked membranes for corneal tissue engineering Weichang Lia, Yuyu Longa, Yang Liua, Kai Longa, Sa Liua, Zhichong Wangb, Yingjun Wanga and Li Rena*
Downloaded by [University of Kent] at 09:45 14 December 2014
a School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641, P.R. China; bState Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou 510060, P.R. China
(Received 19 April 2014; accepted 10 September 2014) This article describes a chitosan–collagen composite membrane as corneal tissueengineering biomaterials. The membrane was prepared by dissolving the chitosan into collagen with the weight ratio of 0, 15, 30, 45, 60, and 100%, followed by crosslinked with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide. Mechanical properties, contact angles, and optical transmittance were determined and compared between chitosan membrane and crosslinking composite membrane. As a result, the optical transparency and mechanical strength of the chitosan–collagen membranes were significantly better than that of the sample of chitosan. In addition, in vitro cell culture studies revealed that the collagen has no negative effect on the cell morphology, viability, and proliferation and possess good biocompatibility. Overall, the dendrimer crosslinked chitosan–collagen composite membranes showed promising properties that suggest that these might be suitable biomaterials for corneal tissueengineering applications. Keywords: 1-ethyl-3-(3-dimethylaminopropyl) collagen; crosslinked membranes
carbodiimide
(EDC);
chitosan;
1. Introduction The cornea, which is the transparent, avascular, surface layer of the eye, could protect the intraocular tissues. Approximately, 285 million people worldwide are suffering from impaired vision; of these, 2.85 million have corneal opacities.[1] Allograft cornea transplantation is an effective method to resolve this disease. However, there are some limiting factors, such as the shortage of donor corneas, the rejection to the donor grafts in many patients and unprofessional skills for corneal grafting in some underdeveloped countries.[2] Tissue-engineering technology provides a new way to cure the corneal diseases, and the preparation of an ideal corneal tissue-engineering scaffold plays a key role. An ideal corneal scaffold material should not only have good biocompatibility and controllable degradability, but also have suitable optical transmittance and mechanical properties. In recent years, different corneal substitutes have been developed by using amniotic membrane,[3–5] chitosan,[6] fibrin,[7,8] caprolactone,[9] collagen hydrogel,[10] and other biomaterials. Although these corneal grafts exhibit good biocompatibility, the microstructure of the natural cornea is not imitated completely. *Corresponding author. Email: [email protected] © 2014 Taylor & Francis
Downloaded by [University of Kent] at 09:45 14 December 2014
Journal of Biomaterials Science, Polymer Edition
1963
So researchers are still developing new materials with optimal structures for clinic corneal transplantation. Among these materials, chitosan is a linear polysaccharide consisting of randomly distributed glucosamine and N-acetylglucosamine repeat units, and is derived from N-deacetylation of chitin.[11] Important properties of chitosan are biocompatible, biodegradable, and nontoxic nature, making this polymer suitable for extensively investigated as a material for various tissue-engineering applications.[12,13] Chitosan membrane is easily prepared due to its physicochemical properties, such as permeability, tensile strength, and adhesion property.[14] However, inherent water sensitivity and relatively low-stability properties still limit the use of chitosan membranes for a wider range of applications, especially in moist environments.[15] Many materials have been used to improve the chitosan membrane, such as nanowhiskers,[15] poly(vinyl alcohol),[16] or collagen.[14] Among these materials, collagen was focused by researchers as it is one of the main components of extracellular matrix, and is well known for excellent biocompatibility, low antigenicity, and biodegradability. In this study, we developed a biomimic corneal material containing chitosan and collagen crosslinked with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC). We then employed scanning electron microscope (SEM) and PC spectrophotometer to characterize the materials, and reported their biocompatibility with human corneal epithelial cells. 2. Materials and methods 2.1. Materials Chitosan (degree of deacetylation ≥90%, viscosity
