A block copolymer brush based on functional monomers (N-succinimidyl acrylate and N-adamantylacrylamide) successfully grew on the surface of Fe3O4@SiO2 nanoparticles by surface-initiated reversible addition-fragmentation chain transfer polymerization (SI-RAFT). According to the multiple recognition mechanisms of this material, horseradish peroxidase (HRP) and β-cyclodextrin-modified glucose oxidase (GOx-CD) were constructed into a multienzyme system with an ordered distribution for the cascade reaction, where multifunctional polymer brush-grafted magnetic nanoparticles were used as the scaffolds. The catalytic activity of GOx-CD was enhanced compared with free GOx. In addition to being easily recycled, this multienzyme system exhibited an outstanding conditional stability compared with the free enzyme system. After being reused 8 times, the activity of multienzyme system retained 67.21% of the initial catalytic activity. This strategy provides a novel idea for reusable ordered enzyme immobilization.
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