Galvanostatic method assembled ZIFs nanostructure as novel nanozyme for the glucose oxidation and biosensing

Recently, the composite of soft conductive substrates, such as carbon fiber (CF), with metal-organic frameworks (MOFs) has been employed in a myriad of applications. The composite material has demonstrated exceptional potential in the realm of electrochemical sensing platforms. However, the rapid growth of MOFs on the surface of CF remains a challenge. Herein, we propose a simple galvanostatic method as an effective strategy for rapidly growing zeolitic imidazolate frameworks (ZIFs) on CF, and obtain nano-caltrop-like ZIFs modified CF (NC-ZIFs/CF) glucose (Glu) sensor platform with distinctive morphology. The prepared NC-ZIFs/CF demonstrated significant electrocatalytic activity towards the oxidation of Glu in alkaline media, characterized by a pronounced augmentation in oxidation current density. At an applied potential of 0.4 V, NC-ZIFs/CF exhibited a remarkably broad detection range (3–30,000 μmol/L) and demonstrated outstanding selectivity, repeatability and reproducibility. Additionally, the NC-ZIFs/CF was efficaciously employed for the detection of blood Glu levels in the serum of both normoglycemic and hyperglycemic patients, obtaining highly reliable results. This work demonstrates the feasibility of using galvanostatic method assembly to induce the growth of MOFs on conductive substrates, providing new ideas for electrocatalysis sensors and other electrochemical applications.