A two-dimensional coordination polymer with high laccase-like activity for sensitive colorimetric detection of thiram

In contrast to natural enzymes, nanozymes show promising advantages of low cost and high stability for analytical applications. The simple mix of L-phenylalanine (F) and Cu²⁺ produces two-dimensional nanosheets of a coordination polymer with a high surface area ratio and rich exposed active sites as a novel catalyst. As the mimetic of natural laccase, this nanozyme (F-Cu) can catalyze the oxidative coupling reaction of 2,4-dichlorophenol (2,4-DP) and 4-aminoantipyrine (4-AP) to produce a distinct red product, thus establishing an intuitive and simple method for the detection of thiram. In the range of 0-7.5 μM, the absorbance intensity was linearly related to the concentration of thiram, and the detection limit was 0.0845 μM. The F-Cu nanozyme was successfully applied to the colorimetric detection of thiram in real samples.