A label-free photoelectrochemical sensor based on BiVO4@graphene oxide hybrid for analysis of the antioxidant capacity in food

Antioxidant can protect body from free radical and dietary intake is a major source of antioxidants for human body. Therefore, it is particularly important to evaluate the antioxidant capacity of food and drink in daily diet. Herein, a label-free photoelectrochemical (PEC) sensor based on BiVO4@graphene oxide (GO) hybrid has been developed for antioxidants analysis and applied it to antioxidant capacity detection of real samples. Five representative antioxidants including ascorbic acid (AA), caffeic acid (CA), chlorogenic acid (CHA), fisetin (FT) and quercetin (QT) were determined by this PEC sensor to acquire photocurrent response at different concentrations. This PEC sensor exhibited excellent sensitivity and anti-interference. Furthermore, antioxidant capacity of food samples was assessed utilizing this PEC sensor, indicating the practicability and accuracy of this PEC sensor. This study suggests that BiVO4@GO composites constructed PEC sensor can provide a practical and fast method for detecting antioxidant capacity in the field of food.