交联方法对草鱼皮胶原蛋白海绵性能的影响

摘要

In this study, the effect of crosslinking method on biological properties of grass carp skin collagen sponge was discussed. Collagen was extracted from skin of grass carp ( Ctenopharyngodon idellus) and collagen sponge was prepared from this collagen. Then,this collagen sponge was crosslinked with different methods,such as UV, dehydrothermal, EDC/NHS and glutaraldehyde crosslinking processes. At the same time, the biological and mechanical properties of those collagen sponges, including degree of crosslinking, denaturation temperature,tensile strength and enzymatic sensitivity in vitro,were evaluated and compared. Experiment results indicated that the grass carp skin collagen was type I collagen. The degree of crosslinking of different crosslinking methods decreased in the order of glutaraldehyde (72. 0% ) > EDC/ NHS(32. 5% ) > dehydrothermal(29. 9% ) > UV( 15. 6% ). Compared with control collagen sponges,the denaturation temperature (67. 4 ℃), tensile strength ( 125. 6 kPa)and enzymatic sensitivity in vitro of collagen sponges crosslinked by glutaraldehyde were significantly improved ( P < 0. 05 ); EDC/NHS crosslinking could lead to obvious increasing in denaturation enthalpy (6. 86 J/g)and moderate improving on tensile strength (98.6 kPa) and enzymatic sensitivity for collagen sponge ( P < 0. 05). The changes of biological and mechanical properties of collagen sponges after being crosslinked by dehydrothermal and UV crosslinking processes were not notable. The results of FTIR showed that glutaraldehyde crosslinking could improve properties of collagen sponges by forming new covalent bond in triple helix structure of collagen, while EDC/NHS crosslinking do that by forming new hydrogen bonds among collagen molecules. This research shows that glutaraldehyde and EDC/NHS crosslinking could lead to obvious improvement in properties of collagen sponges but the influences on properties of collagen sponges after being crosslinked by dehydrothermal and UV crosslinking processes were limited.%为探讨不同交联方法对草鱼皮胶原蛋白海绵材料性能的影响,实验以草鱼鱼皮为原料,提取、纯化胶原蛋白并制备胶原海绵材料.在此基础上,分别用紫外交联、热交联、戊二醛交联以及EDC/NHS交联方法处理胶原海绵,通过测定材料的交联度、热变性温度、拉伸强度和体外抗酶降解性能,比较了不同方法的交联效果.结果发现,提取所得的草鱼皮胶原蛋白为典型的Ⅰ型胶原；经不同方法交联处理后,海绵材料交联度依次为戊二醛(72.0％) ＞EDC/NHS(32.5％)＞热交联(29.9％)＞紫外交联(15.6％)；与对照胶原材料相比,戊二醛处理后,胶原材料的热变性峰值温度(67.4℃)、最大拉伸强度(125.6 kPa)和体外抗酶降解性能均有显著提升(P＜0.05)；EDC/NHS处理后,胶原材料的热变性焓显著提升(6.86 J/g),同时材料的拉伸强度(98.6 kPa)和体外抗酶降解性能也得到适度增加(P＜0.05).紫外交联和热交联对草鱼皮胶原材料性能的改善作用比较有限,并可能导致胶原分子的部分变性.红外光谱的分析结果表明,戊二醛处理可导致草鱼皮胶原三螺旋分子内产生新的共价键交联从而使材料性能改善,而EDC/NHS处理主要导致胶原分子间产生新的氢键交联并可提高胶原材料的稳定性.研究表明,戊二醛和EDC/NHS交联能有效提高胶原海绵材料的性能,而热交联和紫外交联对材料性能的改善作用非常有限.