An efficient differential sensing strategy for phenolic pollutants based on a nanozyme with polyphenol oxidase activity

Abstract

To realize the efficient differential sensing of phenolic pollutants in sewage, a novel sensing strategy was successfully developed based on a nanozyme (GMP‐Cu) with polyphenol oxidase activity. Phenolic pollutants can be oxidized using GMP‐Cu, and the oxidation products reacts subsequently with 4‐aminoantipyrine to produce a quinone‐imine compound. The absorption spectra of final quinone‐imine products that resulted from different phenolic pollutants showed obvious differences, which were due to the interaction difference between GMP‐Cu and phenolic pollutants, as well as the different molecular structures of the quinone‐imine products from different phenolic pollutants. Based on the difference in the absorption spectra, a novel differential sensing strategy was developed. A genetic algorithm was used to select the characteristic wavelengths at different enzymatic reaction times. Hierarchical cluster analysis and PLS‐DA algorithms were utilized for the discriminant sensing of seven representative phenolic pollutants, including hydroquinone, resorcinol, catechol, resorcinol, phenol, p‐chlorophenol, and 2,4‐dichlorophenol. A scientific wavelength selection algorithm and a recognition algorithm resulted in the successful identification of phenolic pollutants in sewage with a discriminant accuracy of 100%, and differentiation of the phenolic pollutants regardless of their concentration. These results indicated that a sensing strategy can be used as an effective tool for the efficient identification and differentiation of phenolic pollutants in sewage.

Nanozymes: powerful catalytic materials for environmental pollutant detection and degradation

“…Such laccase mimic-based assays have also been developed for phenol sensing. [107][108][109][110][111][112][113][114][115][116][117][118][119][120][121][124][125][126][127][128] In a representative study, Liu's group synthesized a guanosine monophosphate (GMP) chelated Cu-based material and found that the material exhibited excellent laccase-mimicking activity. 121 They employed epinephrine as a laccase substrate and found that a colored oxidation product was formed (Fig.…”

“…Fortunately, there are several nanozyme-based sensors arrays developed to realize this goal. 106,120,123,[126][127][128][129][130][131] For example, we proposed a high-performance and convenient sensor array for optical discrimination of phenolic contaminants through using Fe 3 O 4 NPs as a peroxidase imitator. 106 The synthesized Fe 3 O 4 NPs exhibited high activity to catalytically accelerate the reaction of 4-AAP, H 2 O 2 and phenolic substances, presenting a notable Environmental Science: Nano Critical review color change to reveal the content of the analyte (Fig.…”