Ag/P(St-MMA)纳米复合高分子微球固定化青霉素酰化酶的研究

通过溶剂热法和无皂乳液聚合相结合,制备了P(St-MMA)高分子纳米微球.并以吸附沉积的方式在其表面沉积了Ag金属纳米粒子,最后将青霉素酰化酶共价连接在微球表面.初步研究了微球直径、银的质量分数等因素对固定化酶活力的影响.结果显示随着微球直径减小,固定化酶的偶联率和活力逐渐增加;银纳米粒子最多将固定化酶的偶联率和活力分别提高了42%和72%,固定化酶的最大表观活力(以干重记)达到了1 869 u/g,明显高于其它高分子载体固定化青霉素酰化酶的活力;实验证明银纳米粒子在青霉素水解过程中没有催化活力,但能大大提高青霉素酰化酶的催化活力.

Preparation and characterization of Ag/P(St-MMA) and application in the immobilization of penicillin acylase

P(St-MMA) spheres were synthesized in emulsifier-free system with solvothermal method.Silver nanoparticles were deposited on the surface of the copolymer spheres,then penicillin acylase was coupled on the spheres with covalent linkage.Effect of some factors,such as diameters of copolymer spheres,content of silver,ratio of enzyme to copolymer spheres,was studied.Results showed that coupled yield and activity of the immobilized enzyme increased with the decrease of diameter of spheres;silver nanoparticles could improve the coupled yield and activity of immobilized enzyme by 42% and 72% respectively,the maximum of activity of immobilized enzyme was up to 1869 u/g,which was better than the enzyme coupled on the polymer spheres;it was also confirmed that silver nanoparticles had no catalysis in the hydrolysis of penicillin G potassium salt,but could improve the catalysis of immobilized penicillin acylase greatly.