角膜修复材料的制备及生物相容性研究

发布时间：2018-06-01 00:07

本文选题：改性壳聚糖 + 胶原　；参考：《华南理工大学》2012年硕士论文

【摘要】：角膜病已经成为全球第二大致盲眼病，目前角膜移植是角膜盲患者重见光明的唯一有效手段。然而角膜移植存在供体来源匮乏的问题。为解决这一问题，需要寻找可靠的供体来源，角膜修复材料成为研究的热点。角膜修复与重建为角膜盲患者重见光明提供了新的途径，这一领域的一个重要方面就是角膜修复材料的制备。角膜修复材料要求具有优异的眼组织相容性、可控降解性，良好的光学性能，适宜的力学强度与良好的营养物质透过性，以保证能与眼组织相容，并促进角膜组织的再生与修复。本研究以胶原、明胶为基体，通过与改性壳聚糖、生物表面活性剂A15等交联复合的方法制备出光学性能良好、眼组织相容性优异，具有良好营养物质透过性和适宜力学强度的角膜修复材料，并对其眼组织相容性和促进组织再生性能进行初步探讨。采用碳二亚胺交联法制备了胶原交联膜和不同A15含量的A15-胶原复合膜，考察A15组分的比例对复合膜性能的影响。结果表明，随着A15含量增加，复合膜的透光率逐渐升高，最大值达90%；折光率随着A15含量的增加而减小，与透光率变化趋势相反；随着A15含量增加，复合膜含水量增加，湿态拉伸强度下降，当A15含量大于10%时，复合膜含水量达到98%以上；各复合膜对葡萄糖、色氨酸和氯化钠均具有良好的渗透性，其中A15含量为2%的复合膜对三种物质的渗透性能最优。人角膜上皮细胞（HCEC）在A15-胶原复合膜上的黏附、生长与增殖优于胶原交联膜，且后期的细胞增殖优势较明显。A15-胶原复合膜植入兔眼角膜后在眼内维持透明，，无明显炎性与排斥反应，术后5个月可观察到少量基质细胞长入植片表面，显示出良好的眼组织相容性。为提高胶原膜的眼组织相容性，本研究将具有良好抗菌抗炎性的改性壳聚糖与胶原复合，采用碳二亚胺交联法制备了改性壳聚糖-胶原交联膜，并与胶原交联膜的理化性能和生物相容性进行比较。结果表明，改性壳聚糖的加入改善了胶原膜的透光率，折光率则略低于胶原交联膜；改性膜的含水量为72.9%，低于胶原膜的含水量，与人角膜接近；改性壳聚糖的加入显著提高了复合膜的拉伸强度，达到2MPa以上；胶原膜和改性膜对葡萄糖、色氨酸和氯化钠的渗透率均接近或优于人角膜。HCEC在改性膜上的黏附、生长良好，改性壳聚糖的加入有利于细胞增殖。改性膜植入兔眼角膜后无明显炎性和排斥反应，术后7个月植片表面可观察到少量基质细胞长入，显示出良好的眼组织相容性。但改性膜植入后发白，眼内透明性较低。为改善壳聚糖复合膜的眼组织相容性，本研究采用碳二亚胺交联法，将改性壳聚糖与明胶复合制备改性壳聚糖-明胶交联膜，并与壳聚糖-明胶交联膜的理化性能和生物相容性进行比较。结果表明，改性壳聚糖复合膜较壳聚糖复合膜具有更高的含水量，达73.47%，湿态拉伸强度则低于壳聚糖复合膜，为0.94MPa；两复合膜均具有较高的透光率，最大值达95%；改性壳聚糖复合膜的折光率略高于壳聚糖复合膜，对葡萄糖、色氨酸和氯化钠的渗透性能亦优于壳聚糖复合膜。HCEC在两种膜上生长、增殖良好；改性壳聚糖复合膜植入兔眼角膜后，无明显炎性反应，角膜与植片维持透明；术后16周植片完全降解，降解产物对眼组织无毒、无刺激，表现出良好的眼组织相容性。壳聚糖复合膜在兔角膜内则引起较严重的炎性反应，角膜化脓、水肿，眼组织相容性较差。
[Abstract]:Corneal diseases have become the only effective method for corneal transplantation , which is the only effective method to treat corneal diseases .

A15 - collagen composite membrane with collagen cross - linked membrane and different A15 content was prepared by carbodiimide crosslinking method . The influence of the ratio of A15 components on the properties of composite membrane was investigated . The results showed that the light transmittance of composite membrane increased with the increase of A15 content , and the maximum value reached 90 % .
The refractive index decreases with the increase of A15 content , which is opposite to the change trend of light transmittance ;
With the increase of the content of A15 , the water content of the composite membrane is increased and the wet tensile strength decreases , and when the content of A15 is more than 10 % , the water content of the composite membrane reaches above 98 % ;
Human corneal epithelial cells ( HCEC ) had an excellent permeability to glucose , tryptophan and sodium chloride . The adhesion , growth and proliferation of human corneal epithelial cells ( HCEC ) on A15 - collagen composite membranes were superior to that of collagen cross - linked membranes .

In order to improve the ocular tissue compatibility of collagen membrane , the modified chitosan - collagen cross - linked membrane was prepared by carbodiimide crosslinking method , and the physicochemical properties and biocompatibility of collagen cross - linked membrane were compared . The results showed that the addition of modified chitosan improved the light transmittance of collagen membrane , while the refractive index was slightly lower than that of collagen cross - linked membrane .
The water content of the modified membrane was 72.9 % , which was lower than the water content of the collagen membrane and was close to the human cornea .
the addition of the modified chitosan remarkably improves the tensile strength of the composite membrane and reaches above 2MPa ;
The permeability of the collagen membrane and the modified membrane to glucose , tryptophan and sodium chloride was close to or better than that of the human cornea . The adhesion and growth of HCEC on the modified membrane were good . The addition of modified chitosan was beneficial to cell proliferation . After the modified membrane was implanted in the rabbit cornea , there was no obvious inflammatory and rejection reaction .

In order to improve the ocular tissue compatibility of chitosan composite membrane , the modified chitosan - gelatin crosslinked membrane was prepared by compounding modified chitosan and gelatin by carbodiimide crosslinking method . The results showed that the modified chitosan composite membrane had higher water content , 73.47 % than that of chitosan composite membrane , and the wet tensile strength was lower than that of chitosan composite membrane , which was 0.94 MPa ;
the two composite films have high light transmittance , and the maximum value is up to 95 percent ;
The refractive index of the modified chitosan composite membrane was slightly higher than that of chitosan composite membrane . The permeation properties of glucose , tryptophan and sodium chloride were better than that of chitosan composite membrane .
After the modified chitosan composite membrane was implanted into rabbit cornea , there was no obvious inflammatory reaction , and the cornea and the implant remained transparent ;
After 16 weeks of operation , the grafts were completely degraded , and the degradation products were non - toxic and non - irritating to the ocular tissues . The chitosan composite membrane caused severe inflammatory reaction , corneal pus , edema and poor ocular tissue compatibility in the rabbit cornea .
【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R318.08

【参考文献】