Metal Nanoclusters: Structure Design, Enzymatic Activity, and Biomedical Applications

Abstract Metal nanoclusters (NCs) are nanomaterials composed of a few to several hundred metal atoms. They typically measure less than 3 nm in size. In addition, their unique structure endows NCs with distinctive properties, including an extremely high specific surface area, quantum size effects, catalytic activity, enzyme-like activity, biofilm permeability, light-harvesting capabilities, optical properties, and tunable physicochemical characteristics. Because of these properties and activities, NCs have attracted widespread attention in the biomedical field. This review summarizes the preparation strategies, characterization methods, enzyme-like activities, and biomedical applications of NCs. First, common preparation strategies for NCs and their respective advantages and disadvantages are introduced. Second, relevant characterization methods for NCs are discussed. Lastly, the applications of NCs in antibacterial, anti-inflammatory, anticancer, and antiviral therapies are summarized. Additionally, this review provides a critical summary of the limitations of existing NCs in terms of synthesis and biomedical applications and predicts future trends, with the aim of inspiring researchers in related fields.