Modulation of the enzyme-like activity of CuAsp nanozyme by gallic acid and the selective detection of bisphenol A in infant food packaging

The activity modulation of nanozymes with multi-enzymatic activities has both opportunities and challenges in practical applications. In this study, we found firstly that gallic acid erosion had a significant inhibitory effect on the peroxidase-catalyzed colorimetric reaction process of copper aspartate nanozyme prepared based on aspartic acid and copper (CuAsp), and the laccase-like catalytic activity remained almost unchanged. A sensing strategy for bisphenol A was then developed based on the laccase-like activity of GA-CuAsp synthesized by gallic acid (GA) acid erosion of CuAsp, which may have less interference due to the peroxidase-like activity. The developed sensing strategy had good selectivity and interference resistant ability, with a detection limit of 0.75 μmol L^-1. In addition, the method was successfully applied to detecting BPA in plastic bottled drinking water samples and infant food packaging.