Colorimetric Test Paper for H2O2 Determination Based on Peroxidase-Like Activity of an AuFe/ZIF-8-Graphene Composite

摘要

Herein, we prepared a bisuppport-based bimetallic nanoparticle composite AuFe/ZIF-8-graphene. It exhibited high peroxidase activity compared to those hybrids without graphene support, which demonstrated the regulatory effect of graphene on the catalytic activity. SEM, TEM, EDX, XRD, FT-IR and XPS characterization showed that Au and Fe3O4 NPs were successfully immobilized on ZIF-8-rGO carriers. Kinetic analysis confirmed that the fabricated composites showed better K-m and V-max for H2O2 than HRP and some other reported peroxidase mimics. Under the optimal conditions, a sensing assay for H2O2 determination was constructed with a linear detection range of 0.01-2.5 mM and a detection limit of 0.63 mu M. On this basis, a colorimetric test paper with its standard card was prepared for rapid visualization detection. It realized H2O2 detection in the range of 0.01-500 mM and was further successfully applicated in the semi-quantitative detection of H2O2 in actual spiked water samples. This achievement was expected to encourage the development of rapid visual detection for other pollutants in environmental and medical field.