Sb-doped FeOCl nanozyme-based biosensor for highly sensitive colorimetric detection of glutathione.

Abstract

Nanozymes have been emerging as substitutes for natural enzymes to construct biosensors towards biomolecular detection. However, the detection of glutathione (GSH) by nanozyme-based biosensors still remains agreat challenge for research on catalytic activity enhancement and thedetection mechanism. In this work, Sb-doped iron oxychloride (Sb-FeOCl) with awell-defined nanorod-like structure is prepared by high-temperature calcination. Sb-FeOCl nanorods have high peroxidase-like activity, which can catalyze the decomposition of H2O2 into ·OH and then oxidize 3,3',5,5'-tetramethylbenzidine (TMB). In view of these intriguing observations, a reliable colorimetric method with a simple mixing and detection strategy is developed for the detection of GSH. The linear range of GSH detection is 1-36μM. The detection limit of GSH reaches a low level of 0.495μM (3σ/slope). The GSH sensing system also exhibits excellent specificity and anti-interference. Taking advantage of the advantages of theSb-FeOCl nanorod-based biosensor, it can be used to quantitatively detect GSH levels in human serum. It can be anticipated that the Sb-FeOCl nanorods have broad prospects in the field of enzymatic biochemical reactions.