An efficient enzyme cascade bio‐platform based on metal‐organic frameworks nanozyme for the detection of glucose

Abstract Objective Enzyme cascade reaction typically involves the synergistic action of two or more enzymes. It is an efficient tool in the field of biosensing. In this research, with the combination of natural enzyme and nanozyme, a high‐performance enzyme cascade bio‐platform is constructed for sensing of H2O2 and glucose. Methods The enzyme cascade bio‐platform consisting of natural enzyme glucose oxidase (GOX) and nanozyme (hemin@ZIF‐8) was constructed through one‐step co‐precipitation method. The morphology and structure of the composites were characterized by using scanning electron microscopy, x‐ray diffraction and Fourier transform infrared spectrometer. UV‐vis spectrophotometer was used to research the catalytic activity and sensing performances of enzyme cascade bio‐platform. Results The synergistic catalysis between hemin and ZIF‐8 in hemin@ZIF‐8 nanozyme resulted in highly efficient peroxidase‐like activity, which could be used for H2O2 sensing. The porous structure of the metal‐organic framework provided a good microenvironment for loading the natural enzyme, guaranteeing the enzyme activity and spatial proximity of enzymes. The bio‐platform achieved the sensitive detection of glucose with low detection limit of 7.15 μM. Due to the color change in the catalytic reaction, this bio‐platform can be used for detecting glucose qualitatively and semi‐quantitatively with the naked eye. Conclusions The constructed efficient enzyme cascade bio‐platform combined the advantages of natural enzyme and nanozyme. This research not only expanded the application possibilities of nanozyme‐based enzyme cascade system, but also offered an effective strategy for the development of simple, rapid and reliable sensing methods for real application.