Preparation of a Light‐Sensitive and Reversible Dissolution Copolymer and Its Application in Lysozyme Purification

Abstract A novel light‐sensitive and cation‐exchange copolymer (P NBCC ) has been synthesized by random copolymerization of chlorophyllin sodium copper salt, crylic acid, n ‐butyl acrylate, and N ‐isopropylacrylamide. The P NBCC copolymer showed reversible dissolution and could be precipitated by 488 nm laser irradiation with the least light density of 1.70 × 10 5 W/m 2 . By optimizing the ratio of monomers, pH, and ion concentration, over 95% copolymer was recovered by laser irradiation. The copolymer was used to purify lysozyme as light‐sensitive cation exchanger, and its adsorption matched a Langmuir adsorption isotherm with maximum adsorption capacity of 98 900 U/g and dissociated constant of 852 U/mL. By applying the copolymer to the separation of lysozyme from egg white, the specific activity of lysozyme was improved from 399 to 6346 U/mg and the recovery of lysozyme achieved 81.3%.