李亚,郭杰,胡集铖,韩萍芳

• 1:南京工业大学生物与制药工程学院
• 2:南通农业职业技术学院环境与资源系

摘要(Abstract)：

以凹土为原料,醋酸铁为γ-Fe2O3前驱体,湿法工艺制备了磁性凹土基复合材料,并用偶联剂γ-氨丙基三乙氧基硅烷对磁性凹土基复合材料进行了氨基改性。XRD、TEM、FT-IR、VSM表征结果表明:γ-Fe2O3粒子均匀负载于凹土层间,粒子直径为4~15 nm;经过改性,氨基接枝于磁性凹土基复合材料表面;改性前后的磁性凹土基复合材料均具超顺磁性,饱和磁强度分别为13.4和10.7 emu·g-1。以戊二醛为交联剂,以氨基化磁性凹土基复合材料为载体固定化假丝酵母脂肪酶,研究结果表明:相比于游离脂肪酶,固定化脂肪酶的热稳定性和p H稳定性显著提升,重复用于水解反应8次后仍保持约78%的活力,米氏常数是游离脂肪酶的1.28倍,且在外加磁场作用下易于从反应体系分离。

关键词(KeyWords)： 磁性凹土;氨基改性;脂肪酶;固定化;交联

Abstract:

Keywords:

基金项目(Foundation): 江苏省普通高校研究生科研创新计划项目(CXZZ12 0440)

作者(Author): 李亚,郭杰,胡集铖,韩萍芳

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