Developing a novel strategy for light-triggered reversible enzyme immobilization and reuse of support

Abstract

The reuse of support material still hamper the practical application of enzyme immobilization technology in wastewater treatment. Here, a novel strategy based on light-triggered reversible β-cyclodextrin (β-CD)-Azobenzene(Azo) host-guest interaction was developed. First, magnetic Fe3O4 nanoparticles were coated with porous β-CD-containing polymers(PCDP), and then the Azo-modified enzyme was immobilized in normal condition. The immobilization would enhance the stability and catalytic performance of enzymes, and the easy separation from reaction medium could be available with external magnetic field. Over broad ranges of temperature and pH, the immobilized enzyme showed higher activity than free enzyme, and the phenol removal efficiency retained about 58.63% even after five cycles. Under UV light, the photoisomerization of Azo would lead to disassemble of β-CD-Azo interaction, resulting in the detachment of the enzyme, and phenol removal efficiency decreased to only 16%. The support materials could be recovered for continue enzyme immobilization, results based on cyclic process of enzyme immobilization and detachment strongly demonstrated the detachment of enzyme and excellent reusability of Fe3O4@PCDP. And this strategy was proved to be a practical method based on batch experiments on the removal of phenol by tyrosinase (Tyr)-based remediation.