Carbon dots in the generation of reactive oxygen species for antibacterial therapy: advances and challenges

Bacterial infections remain a major threat to global public health. While antibiotics have been the cornerstone of clinical antibacterial therapy, their efficacy is increasingly compromised by the emergence of resistant bacterial strains. This urgent challenge has accelerated the exploration of alternative antimicrobial strategies. Among these, reactive oxygen species (ROS)-based therapies have emerged as a highly promising approach, offering potent and broad-spectrum antibacterial activity with a low propensity for inducing resistance. Carbon dots (CDs) have garnered significant attention as novel nanomaterials for ROS-mediated antibacterial applications due to their unique combination of intrinsic fluorescence, excellent biocompatibility, and highly tunable physicochemical properties. A key antibacterial mechanism of these materials is their ability to generate ROS in situ within bacterial cells through multiple pathways. This review provides a comprehensive and systematic analysis of the diverse antibacterial strategies enabled by CDs through ROS generation. We categorize and discuss these strategies based on their activation mechanisms: non-irradiation-dependent methods and light- or ultrasound (US)-mediated approaches. By examining the design principles, functional mechanisms, and potential applications of these CD-based ROS generators, this review aims to offer valuable insights and inspire the future development of innovative, efficient, and targeted ROS-mediated antibacterial platforms.