Gene

Catalysis

Adsorption

Engineering

Horseradish peroxidase

Materials science

Embedded system

Robustness (evolution)

Biochemistry

Computer science

Chemical engineering

Biosensor

Porosity

Combinatorial chemistry

Nanotechnology

Organic chemistry

Enzyme

Atom (system on chip)

Metal-organic framework

Nanomaterials

Chemistry

Biosensors and Bioelectronics

Due to robustness, easy large-scale preparation and low cost, nanomaterials with enzyme-like characteristics (defined as 'nanozymes') are attracting increasing interest for various applications. However, most of currently developed nanozymes show much lower activity in comparison with natural enzymes, and the deficiency greatly hinders their use in sensing and biomedicine. Single-atom catalysts (SACs) offer the unique feature of maximum atomic utilization, providing a potential pathway to improve the catalytic activity of nanozymes. Herein, we propose a Fe-N-C single-atom nanozyme (SAN) that exhibits unprecedented peroxidase-mimicking activity. The SAN consists of atomically dispersed Fe─Nx moieties hosted by metal-organic frameworks (MOF) derived porous carbon. Thanks to the 100% single-atom active Fe dispersion and the large surface area of the porous support, the Fe-N-C SAN provided a specific activity of 57.76 U mg-1, which was almost at the same level as natural horseradish peroxidase (HRP). Attractively, the SAN presented much better storage stability and robustness against harsh environments. As a proof-of-concept application, highly sensitive biosensing of butyrylcholinesterase (BChE) activity using the Fe-N-C SAN as a substitute for natural HRP was further verified.

Unprecedented peroxidase-mimicking activity of single-atom nanozyme with atomically dispersed Fe–Nx moieties hosted by MOF derived porous carbon