Palygorskite@Co3O4 nanocomposites as efficient peroxidase mimics for colorimetric detection of H2O2 and ascorbic acid

Nanomaterials with intrinsic enzyme-like activities have attracted extensive research interest as promising alternatives to natural biological enzymes due to their advantages of low cost and high stability. Many artificial enzyme mimics have been successfully applied in the fields of sensing, environmental treatment, and oncotherapy. Herein, novel [email protected] 3 O 4 nanocomposites ( [email protected] 3 O 4 NCs) were fabricated by modifying Pal with Co 3 O 4 nanoparticles through a facile hydrothermal method . The obtained [email protected] 3 O 4 nanocomposites as nanozymes displayed enhanced peroxidase-like activity, which can catalyze the oxidation of 3,3,5,5-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide (H 2 O 2 ) to obtain colored products. Kinetic assay indicated that the [email protected] 3 O 4 peroxidase mimics showed a higher affinity towards TMB than that of natural horseradish peroxidase (HRP). Moreover, a sensitive and selective sensor for colorimetric determination of H 2 O 2 and ascorbic acid (AA) was successfully constructed by using [email protected] 3 O 4 nanocomposites as peroxidase mimics. Furthermore, the proposed assay for sensing of AA in model samples was evaluated with satisfactory results, demonstrating the potential applications in complex biological systems.