Abstract: Mesoporous materials of large pore size(12 nm)were synthesized by the usage of swelling agent. After modification, the mesoporous materials were used as the carriers in the immobilization of penicillin G acylase. Specifically, a study was carried out on the stability of the immobilized enzyme. Penicillin G acylase can catalyze the cleavage of the amide bond in the benzyl penicillin(penicillin G) side-chain to yield phenylacetic acid and 6-aminopenicillanic acid(6-APA). The enzyme is of great pharmaceutical importance, as the product 6-APA is the starting point for the synthesis of many semi-synthetic penicillin antibiotics. The activity of nature PGA is low, which limits the application of PGA. By immobilizing PGA on a solid support, it can be reused and its useful lifetime can be extended because the immobilized PGA is less susceptible to degradation, aggregation, or denaturation.The research results indicate that the functionalization of the internal surfaces of mesoporous solids permitted the enzyme immobilization. The reuse of the catalysts is also possible. The retention activity up to 90% of the PGA is observed in the most favorable case after using for 10 times.

Key words: Mesoporous materials, Penicillin G acylase, Stability