Abstract
Exploring highly active peroxidase mimics at physiological pH is important for the construction of efficient and convenient colorimetric sensing platforms for detecting small biomolecules. In this work, prepared zinc pyrovanadate (Zn3V2O7(OH)(2)center dot 2H(2)O) nanorods exhibit excellent peroxidase-like activity, which is verified by the fast oxidation of colorless 3,3 ',5,5 '-tetramethylbenzidine (TMB) into a blue product (oxTMB) by H2O2 at physiological pH (pH = 7) in 2 min. In addition, the catalytic behaviors of Zn3V2O7(OH)(2)center dot 2H(2)O as a peroxidase-like nanozyme conform to the Michaelis-Menten equation. Scavenger experiments prove that the catalytic activity of Zn3V2O7(OH)(2)center dot 2H(2)O is ascribed to O-2(-) radicals generated in the process of catalysis. Based on the peroxidase-like activity of the Zn3V2O7(OH)(2)center dot 2H(2)O nanozyme, a fast and convenient colorimetric sensor has been constructed to detect H2O2 and epinephrine (EP) under physiological pH. The detection limit of EP is as low as 0.26 mu M. In addition, the feasibility of the proposed sensor has been validated to detect H2O2 in milk and EP in serum.