Covalent immobilization of penicillin G acylase onto chemically activated surface of poly(vinyl chloride) membranes for 6-penicillic acid production from penicillin hydrolysis process I. Optimization of surface modification and its characterization

The covalent immobilization of penicillin G acylase (PGA) onto the surface of NH2–poly(vinyl chloride) (PVC) membranes was studied. PGA was chosen because it plays a relevant role in the pharmaceutical industry, catalyzing the production of an important intermediate for the industrial production of semisynthetic penicillin and cephalosporine. Because PVC has no functional groups in its structure, in this work, we focused on the functionalization of PVC with primary amine functional groups for the covalent immobilization of PGA. This goal was achieved through an aminoalkylation process of the surface of the PVC membranes with ethylene diamine followed by activation with glutaraldehyde to finally immobilize the enzyme. Different factors affecting the modification and activation processes were studied, and their impacts on the catalytic activity of the immobilized PGA were followed. The functionalized membranes were characterized with Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy to verify the modification process. In addition, the changes resulting from the modification in physical characteristics, such as surface roughness, water uptake, and mechanical properties, were monitored. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012