明胶的疏水化及性能表征

Hydrophobic modification of gelatin and the characterization on its performance

利用乙酸酐和苯甲醇,分别对明胶进行乙酰化和酯化反应等疏水化改性,拟改善明胶的疏水性,期望得到不需化学交联的难溶于水的明胶支架.通过乙酰化率分析、红外分析、接触角分析、热重分析、水溶性分析和降解性分析等研究改性后明胶的结构与性能.结果表明成功将疏水基团连接到明胶分子上,改性后明胶疏水性增强,在室温不溶于水,降解速度大大减慢,而热稳定性与原始明胶的基本一致.其中,乙酰化率达93.46%,说明乙酰化反应的条件已达到优化.改性明胶可望单独用于诸如皮肤、软骨修复的支架材料.

Hydrophobic modification of gelatin, including acetylation and esterification, was performed by using of acetic anhydride and benzyl alcohol, in order to improve the hydrophobicity of gelatin and to get water-insoluble gelatin scaffolds without chemical cross-linking. The acetylation rate, IR, contact angle, TGA, water-solubility and biodegradation rate were also examined to evaluate the structures and properties of the modified gelatin. The results showed that hydrophobic groups had been successfully conjugated to gelatin molecules. The hydrophobicity of gelatin was enhanced after modification, and the modified gelatin was insoluble in water at room temperature. The biodegradation rate of the gelatin slowed down greatly, and its thermal stability was the same as the original gelatin. Moreover, acetylation rate reached 93.46%, which demonstrated that the reaction conditions of acetylation had been optimized. These performs indicate that the modified gelatin has a promise in tissue regeneration scaffold alone, such as skin and cartilage regeneration scaffold.