Composites of Fe₃O₄, Ag, and Au Nanoparticles for Dye Degradation and Selective Detection of Glutathione

In comparison with the poor stability, high cost, and difficult preparation of conventional natural enzymes, nanozymes have the obvious advantages of excellent stability, high catalytic activity, multifunctionality, and large-scale preparation. Herein, a series of Fe 3 O 4 NPs-based magnetic composite with dual enzyme-like activities (peroxidase and oxidase) were successfully synthesized by the microwave-assisted method. Among them, the Fe 3 O 4 /Ag Au nanocomposite showed the highest peroxidase-like activity due to the synergistic catalytic effect of Ag and Au bimetallic modifications. Enzyme kinetic studies revealed good kinetic parameters of the Fe 3 O 4 /Ag Au nanocomposite for peroxidase, and it also exhibited a higher affinity for TMB compared to natural horseradish peroxidase. In addition, a method for effective dye degradation and selective detection of glutathione was constructed based on its peroxidase-like activity. Importantly, the remarkable magnetic separation property and the outstanding stability proved the extensive application prospects of the nanozymes in the remediation of water pollution and some biomarker-specific detection.