Carbon dots as an emerging antibacterial agent: Antibacterial mechanism and synthetic optimization

The risking prevalence in antibiotic resistance forces researchers to develop alternative antimicrobial agents. Carbon dots (CDs) have emerged as a type of promising candidates in antibacterial field due to their unique optical properties, excellent biological activity and low toxicity. Herein, we focus primarily on the recent advances in CDs-based antibacterial research. Firstly, the potential antibacterial mechanisms are discussed systematically, including bacterial cell structure damage, photodynamic therapy, photothermal therapy, and metabolic interference. Then, particular attention is given to the synthetic optimization of antibacterial CDs to enhance their antibacterial efficiency, such as the proposed method and precursors chosen, size control, heteroatom doping, surface functionalization of antibacterial CDs. In addition, diverse applications of these antibacterial CDs are discussed briefly. Finally, the current challenges and proposed future directions of antibacterial CDs are outlined, involving deep exploration of antibacterial mechanisms, identification of the antibacterial CDs' structure, precise sterilization, and minimization of the gap between scientific research and clinical use. We hope this review will provide an opportunity for in-depth understanding of the antibacterial CDs, and help to attract more interested researchers to participate and jointly promote the future development of antimicrobial CDs.