Spherical polyelectrolyte brushes as bio-platforms to integrate platinum nanozyme and glucose oxidase for colorimetric detection of glucose

The integration of nanozyme and natural enzyme for cascade reactions has attracted great attention due to their huge potential applications in detection, biomedicine, and catalysis. Here the novel cascade bio-platforms were fabricated by using spherical poly[(2-methacryloyloxyethyl)trimethyl ammonium chloride] (PMOTA) brushes (SPB) as nanoreactors to prepare platinum nanoparticles in situ and as nanocarriers to immobilize glucose oxidase (GOX). The generated Pt nanoparticles possess high stability and peroxidase-like properties, which can catalyze the oxidation of 3,3 ',5,5 '-tetramethylbenzidine (TMB) in the presence of H2O2 to generate blue colored oxidized TMB (oxTMB). And the absorbed GOX can specifically catalyze the oxidation of glucose into gluconic acid and H2O2, while the produced H2O2 is subsequently catalyzed by the Pt nanozymes. Thus, the co-immobilized Pt nanozymes and GOX within SPB (SPB@Pt@GOX) acted as effective biosensors for colorimetric detection of glucose showing high selectivity and great feasibility. This work demonstrates a facile and general strategy to use SPB as bio-platforms to integrate nanozymes and natural enzymes for cascade reactions.

Automated summary

The study demonstrates a facile and general strategy to integrate nanozymes and natural enzymes for cascade reactions using SPB as bio-platforms. The co-immobilized Pt nanozymes and GOX within SPB act as effective biosensors for colorimetric detection of glucose, showing high selectivity and feasibility.