In situ synthesis of protein-loaded hydrogels via biocatalytic ATRP

Protein-loaded hydrogels were synthesized via biocatalytic atom transfer radical polymerization (ATRP) for the first time. Laccase from Trametes versicolor acted as the ATRPase for the enzymatic polymerizations and was in situ loaded into the porous network of poly(ethylene glycol)-based hydrogels. The use of additional ligands such as tris(2-(dimethylamino)ethyl)amine could significantly increase the polymerization conversion, allowing the polymerizations to occur at ambient or even lower temperature. The rheology and water uptake ratio of hydrogels could be tuned by using different cross-linkers. Immobilized enzymes in the hydrogels have shown decreased yet considerable activity compared with pristine laccase. The hydrogels could be facilely recovered and reused up to six times with no significant decrease in enzyme activity. Such hydrogels were successfully used for the oxidative polymerization of hydroquinone and may find potential applications in protein delivery and water treatment.