磁性壳聚糖微球的制备及对乳酸氧化酶的固定化研究

Preparation of magnetic chitosan microsphere and its application in immobilizing lactate oxidase

以戊二醛为交联剂制备了磁性壳聚糖微球,对其形貌和结构进行了观察和分析,结果表明,载体呈规则圆球状,表面平滑,分散性较好,平均粒径为3μm。以此载体对乳酸氧化酶进行了固定化,并对固定化乳酸氧化酶的催化条件进行了研究。固定化酶的最适催化温度为50℃,最适pH为6.5~7.5;在60℃保温40 min后,固定化酶活仍保持60%;连续操作5次后,固定化酶活仍保持70%以上。与游离酶相比,固定化乳酸氧化酶的使用效率明显提高,并且具有良好的储存性。

Magnetic chitosan microsphere was prepared with glutaraldehyde as crosslinking agent.Its shape and structure were observed and analyzed,and the results showed that the particle size of carriers was small(3 μm),symmetrical and well dispersed.Lactate oxidase(LOD) was immobilized with this carrier,and the enzymatic properties were investigated.The optimal catalytic pH value of the immobilized LOD was 6.5-7.5 and the optimal temperature was 50℃.After 40 min incubation at 60℃,60% activity of the immobilized LOD still remained.After 5 times consecutive catalytic process,the activity of the immobilized LOD remained 70%.The stability of operation and reservation of the immobilized LOD was superior to that of the free LOD.