Fe_(3)O_(4)磁性载体的制备及其固定脂肪酶的研究

Preparation of Fe_(3)O_(4) Magnetic Carrier and Its Immobilization of Lipase

利用化学共沉淀法制备Fe_(3)O_(4)磁性内核,并以其为载体采用吸附法结合溶胶-凝胶法固定脂肪酶。分别以内核包硅之前和包硅过程中加入脂肪酶两种方法固定脂肪酶,对两种方法得到的固定化脂肪酶测定酶活回收率。实验表明:先吸附脂肪酶后包硅所得酶活回收率较高。同时对固定条件进行优化,在给酶浓度1.5 g/L、pH 8.5、温度30℃、固定时长6 h条件下进行包硅,所得固定酶酶活回收率最高为40.57%。且脂肪酶经过固定后具有了较好的重复使用性和储存稳定性。磁性载体的引入有利于脂肪酶从反应体系中分离,降低了使用成本。而吸附法与溶胶-凝胶法相结合,增加了脂肪酶的固定稳定性。

The Fe_(3)O_(4) magnetic carrier was synthesized using a chemical co-precipitation method,and the lipase was immobilized on the Fe_(3)O_(4) magnetic carrier through the adsorption method combined with the sol-gel method.Two methods were investigated for immobilizing lipase:adsorbing lipase before or during the sol-gel process,and the activity recovery rates of both methods were measured.The experiments showed that the activity recovery rate of lipase immobilized via adsorption before the sol-gel process was comparatively higher.After optimizing the immobilization conditions,it was determined that under alipase concentration of 1.5 g/L,pH 8.5,temperature at 30℃,fixation time of 6 hours,the highest activity recovery rate of lipase achieved was 40.57%.After immobilization,the lipase exhibited good reusability and storage stability.The incorporation of magnetic carriers facilitates efficient separation of lipase from the reaction system,thereby reducing operational costs.Furthermore,combining adsorption with sol-gel techniques enhanced the stability of lipase immobilization.