Single-Atom Catalysts for Biomedical Applications: Enzyme-Like Activity, Precise Regulation, and Application Frontiers

The discovery of nanoenzymes offers a novel approach to mimicking natural enzymes with both high stability and low cost. However, their complex surface structures and compositions often result in ambiguous catalytic sites and low atomic utilization. The emergence of single-atom catalysts (SACs) has overcome this bottleneck. By dispersing metal atoms in isolated form on a support, these catalysts achieve maximum atomic utilization and uniform coordination environments. This makes it possible for people to perfectly replicate the electrons and geometric structures of natural metallases on an atomic scale to construct SACs. These materials not only inherit the advantages of nanoenzymes, but also provide an ideal platform for clarifying the catalytic mechanism because of their clear and precisely controllable active sites. By regulating the central metal ion type, the type of coordinating atom and the carrier effect, its catalytic activity can be effectively optimized. Based on the enzyme-like activity of SACs and its activity regulation mechanism, this review explains the application of SACs in the field of biomedicine.