Copper-based nanomaterials as peroxidase candidates for intelligent colorimetric detection and antibacterial applications

With natural polyphenol compound tannic acid (TA) as the ingredient, copper tannate (CuTA) nanolayer material was formed by self-assembly under the conditions of heating and copper ion. Copper ion and tannic acid could coordinate to form Cu–O–C structure which was similar to the Fe–N–C structure of natural heme enzymes. In addition, the obtained CuTA nanomaterial possessed excellent peroxidase-like catalytic activity and stability. Based on this excellent enzymatic activity, CuTA nanomaterials could be used for colorimetric detection of hydrogen peroxide with a smartphone and decomposition of organic dyes. Based on the structural characteristics and catalytic activity, the copper tannate nanozymes could also serve as potential antibacterial reagents to effectively inhibit the growth of gram-negative and positive bacteria in a low hydrogen peroxide level. This work may promote the exploration of novel peroxidase mimetics and broaden the applications of nanozymes.