PVC dechlorination residues as new peroxidase-mimicking nanozyme and chemiluminescence sensing probe with high activity for glucose and ascorbic acid detection

Abstract

Polyvinyl chloride (PVC) dechlorination residues urgently need to be used to improve PVC recycling efficiency. Herein, PVC dechlorination residues were used for visual colorimetry and chemiluminescence (CL) sensing for the first time. It was found that the dechlorination residues of PVC and iron chips treated by subcritical water showed excellent peroxidase-mimicking activity and could catalyze enzyme substrate 3,3′,5,5′-tetramethylbenzidine (TMB) oxidation to produce blue product. Based on this, residues colorimetric analysis was developed to detect hydrogen peroxide in the range of 3.2 × 10−8–9.5 × 10−5 M and glucose in the range of 8.9 × 10−6–9.2 × 10−4 M. The detection limits were estimated to be 4.5 × 10−9 M for hydrogen peroxide and 6.8 × 10−7 M for glucose, respectively. The kinetic investigation of enzymatic reaction confirmed that the simulated enzyme activity of the residues was much stronger than that of the previously synthesized nanocomposite (The Km and Vmax of the residue system with TMB as the substrate were 0.298 mM and 207.3 × 10−8 M S−1, respectively). In addition, the residues could alone trigger luminol CL reaction to produce strong CL signal with no need for oxidant, and the residues CL analysis was developed for detection of ascorbic acid (AA) in the range of 1.5 × 10−12 M to 7 × 10−8 M with the detection limit of 0.32 pM. The results affirmed that the residues were fantastic colorimetric and CL sensing material, which not only provided vital reference for residues applications in other sensing assays, but also was important for construction of the sensing platforms using wastes.