Single-atom catalysts: Enzyme-mimicking coordinations, platform designs, and biomedical applications

Recent advancements in nanotechnology have resulted in the appearance of single-atom catalysts (SACs), along with a novel class of materials with the potential to mimic the performance of natural enzymes for a wide range of biological applications. Characterized by atomically dispersed metal sites anchored on appropriate substrates, SACs render unique electronic configurations and maximized metal atom utilization. These properties enhance catalytic activity, selectivity, and stability, which makes SACs more efficient than normal nanocatalysts. These intriguing features allow SACs to address key challenges in biomedicine, including enzyme-like activity for biosensing, targeted therapy, and disease prevention. SACs have shown significant potential in cancer treatment, oxidative stress reduction, antimicrobial therapies, real-time biosensing, and bioimaging, closing the disparity gap between nanozymes and natural enzymes. Furthermore, SAC platforms are versatile, allowing surface modifications and the integration of other materials to improve biocompatibility, catalytic performance, and multi-functionality. This study reviews progress in SAC synthesis, coordination environments, and platform designs, proving their transformative potential in biomedicine. In addition, the main challenges of SACs for clinical use, such as improving substrate selectivity and biocompatibility or ensuring long-term stability, are also considered. When these limitations are addressed, SACs promise to revolutionize therapeutic strategies and allow new solutions for diagnostic innovations, precision medicine and disease management. This work contributes to the growing understanding of SACs and their future applications in catalytic biomedicine.