ROS-Catalytic Transition-Metal-Based Enzymatic Nanoagents for Tumor and Bacterial Eradication

The extensive research into developing new nanomedicines during the past few years has witnessed significant progress in diverse biomedical fields, especially for combating drug resistance in antitumor and antibacterial therapies. Recently, transition-metal-based enzymatic nanoagents (TM-EnzNAs) with catalytic production of reactive oxygen species (ROS) have been designed and intensively explored, which have become powerful nanoplatforms and exciting research frontiers in constructing next-generation nanotherapeutics to combat drug-resistant tumors and bacteria. Here, the focus is on the recent design, fundamental principles, and material chemistries in developing and applications of TM-EnzNAs. At first, the different ROS-producing mechanisms and the key factors to enhance ROS level are carefully concluded, and the analytic methods are systematically summarized. Then, the rationally engineered TM-EnzNAs via different synthetic approaches with high ROS producing efficiencies are comprehensively discussed, especially the catalytic activities, mechanisms, and structure-function relationships. After that, the representative applications of these ROS-catalytic TM-EnzNAs for antitumor and bacterial eradication are summarized in detail. Finally, the primary challenges and future perspectives have also been outlined. It is anticipated new therapeutic insights into combating drug-resistant tumors and bacteria will be provided, and significant new inspiration for designing future enzymatic nanoagents is offered.