Physics

Nanomaterials

Kinetics

Nanotechnology

Enzyme

Combinatorial chemistry

Active site

Catalysis

Peroxidase

Chemistry

Materials science

Catalytic efficiency

Quantum mechanics

Biochemistry

Enzyme kinetics

Nature Protocols

Nanozymes are nanomaterials exhibiting intrinsic enzyme-like characteristics that have increasingly attracted attention, owing to their high catalytic activity, low cost and high stability. This combination of properties has enabled a broad spectrum of applications, ranging from biological detection assays to disease diagnosis and biomedicine development. Since the intrinsic peroxidase activity of Fe3O4 nanoparticles (NPs) was first reported in 2007, &gt;40 types of nanozymes have been reported that possess peroxidase-, oxidase-, haloperoxidase- or superoxide dismutase–like catalytic activities. Given the complex interdependence of the physicochemical properties and catalytic characteristics of nanozymes, it is important to establish a standard by which the catalytic activities and kinetics of various nanozymes can be quantitatively compared and that will benefit the development of nanozyme-based detection and diagnostic technologies. Here, we first present a protocol for measuring and defining the catalytic activity units and kinetics for peroxidase nanozymes, the most widely used type of nanozyme. In addition, we describe the detailed experimental procedures for a typical nanozyme strip–based biological detection test and demonstrate that nanozyme-based detection is repeatable and reliable when guided by the presented nanozyme catalytic standard. The catalytic activity and kinetics assays for a nanozyme can be performed within 4 h. Nanozymes are nanomaterials that possess intrinsic enzyme-like properties and are increasingly used in various biological applications. This protocol describes standardized assays of the catalytic activity and kinetics of peroxidase-like nanozymes.

Standardized assays for determining the catalytic activity and kinetics of peroxidase-like nanozymes