The objective of this study was to explore the effects of dehydrothermal treatment (DHT) and glutaraldehyde (GTA) cross-linking on mechanical, biological properties and biodegradation behavior of Nile tilapia skin collagen sponge fabricated by freeze-drying technology. It was found that the GTA cross-linked collagen sponge exhibited a higher degree of cross-linking in comparison with DHT. The extent of increased tensile strength as well as hygroscopicity indicated that GTA cross-linking was superior to DHT in mechanical properties and liquid absorption, which was attributed to different cross-linking mechanisms. Hygroscopicity assay indicated that cross-linking could improve stability of collagen in solutions. No obvious changes in porosity and blood coagulation time were observed whether cross-linking or not. Results from collagenase biodegradation assay in vitro illustrated that GTA-treated collagen sponge was more resistant to collagenase biodegradation, while DHT exhibited negligible resistance. In addition, photochemical stability of collagen sponge was studied by Fourier transforms infrared spectroscopy (FTIR), which indicated that both cross-linking treatments could not change the backbone structure of collagen. Furthermore, the microstructure of collagen sponge was stable after cross-linking. The highly porous and interconnected structure of collagen sponge was helpful to the absorption of wound exudates, supplement of oxygen and cell proliferation, accompanied with good blood compatibility, which indicated that our fabricated collagen sponge could be applied in biomedical materials field as wound dressings.

这项研究的目的是探讨脱水处理（DHT）和戊二醛（GTA）交联对冷冻干燥技术制备的尼罗罗非鱼皮肤胶原蛋白海绵的机械，生物学特性和生物降解行为的影响。发现与DHT相比，GTA交联的胶原海绵具有更高的交联度。拉伸强度和吸湿性增加的程度表明，GTA交联在机械性能和液体吸收方面优于DHT，这归因于不同的交联机理。吸湿性测定表明交联可改善溶液中胶原蛋白的稳定性。无论是否交联，均未观察到孔隙率和凝血时间的明显变化。体外实验表明，经GTA处理的胶原蛋白海绵对胶原酶的生物降解具有更高的抵抗力，而DHT的抵抗力却可以忽略不计。另外，通过傅里叶变换红外光谱（FTIR）研究了胶原蛋白海绵的光化学稳定性，这表明两种交联处理均不能改变胶原蛋白的骨架结构。此外，交联后胶原海绵的微观结构是稳定的。胶原蛋白海绵的高度多孔和相互连接的结构有助于吸收伤口渗出液，补充氧气和促进细胞增殖，并具有良好的血液相容性，这表明我们制备的胶原蛋白海绵可以在生物医学材料领域用作伤口敷料。