摘要 : A simple method was proposed for the preparation of CeVO_4. The as-synthesized CeVO_4 was, for the first time, demonstrated to exhibit both peroxidase-like and oxidase-like activity, which catalyzes the oxidation of 3, 3', 5, 5'-t... 展开 A simple method was proposed for the preparation of CeVO_4. The as-synthesized CeVO_4 was, for the first time, demonstrated to exhibit both peroxidase-like and oxidase-like activity, which catalyzes the oxidation of 3, 3', 5, 5'-tetramethylbenzidine (TMB) to form a typical blue solution in the presence or absence of H_2O_2. Moreover, the mechanism of its dual-enzyme activity was investigated in detail. The Michaelis constant (K_m) value for CeVO_4 (0.136mM) was lower than that of horseradish peroxidase (0.424mM) with TMB as the substrate. Interestingly, hydroquinone (H_2Q), dihydroxybenzene isomer, undergoes reduction accompanying the oxidation of TMB by the CeVO_4 oxidase mimic along with a visible color change, while the other two dihydroxybenzene isomers, i.e., resorcinol (RC) and catechol (CC), do not. Based on these findings, a colorimetric platform was developed to discriminate H_2Q from RC and CC. Under optimal conditions, a linear relationship between the H_2Q concentration and absorbance was observed from 0.05 to 8 μM, and a limit of detection of 0.04 μM was achieved. Moreover, this colorimetric platform can selectively reveal H_2Q concentrations in the presence of other dihydroxybenzene isomers. 收起