DNA-Directed Immobilized Enzymes on Recoverable Magnetic Nanoparticles Shielded in Nucleotide Coordinated Polymers

Immobilizing enzymes is an effective method to construct a multienzyme system for tandem reactions, but the anchored enzymes are too fragile for industrial applications. Here, an enzyme-shielding strategy is described to manufacture a multienzyme system with an “anchor-shield” structure. This system applies the self-assembly of supramolecular nucleotide coordinated polymers (NCPs) of controllable thickness encapsulating glucose oxidase (GOx) which is fixed on magnetic nanoparticles by DNA-directed immobilization. The nanocoating completely shields GOx, protecting it from denaturation and detachment. As a result, the stability of GOx against stresses was enhanced significantly; it maintained 83% and 64% of activity after incubation of 60 and 120 min under 60 °C. Notably, the encapsulated-enzyme retained 94% of activity after 45 days under 4 °C and 81% after 20 cycles, proving excellent reproducibility. More importantly, with the use of NCPs as a peroxidase-mimic, an enzyme–nanozyme cascade was established to be applicable for the removal of common pollutants, suggesting the potential of such magnetically separable systems.