Widespread bacterial infection and the spread of antibiotic resistance exhibit increasing threat to the public and thus require new antibacterial strategies. Carbon quantum dots (CQDs) have been extensively investigated to play fluorescent, catalytic roles and even potential biomedical functions containing sterilization. However, synthetic understanding of the interaction of CQDs and bacteria, the exhibition of antibacterial ability, and the risk of resistance evolution remain lacking. Herein, a simple one-pot method was fabricated to prepare positively charged CQDs (PC-CQDs) as a broad-spectrum antibacterial agent. PC-CQDs possessed effective antibacterial activity against all tested Gram-positive, Gram-negative, and drug-resistant bacteria. Investigation of the antibacterial mechanism of PC-CQDs indicated that small-sized PC-CQDs functionalized with –NH₂ and –NH induced strong adherence behavior on the bacterial cell membrane. Moreover, the entry of PC-CQDs caused conformational changes in the genes and generation of reactive oxygen species in the bacteria. Safety evaluation illustrated that PC-CQDs did not trigger detectable drug resistance or hemolysis. Furthermore, PC-CQDs effectively promoted the antibacterial treatment of mixed Staphylococcus aureus and Escherichia coli infected wound in rats with low in vivo toxicity. These results suggested that PC-CQDs are a potential antibacterial candidate for real wound healing applications in complex bacterial infections and even resistant bacteria-caused infections.

广泛的细菌感染和抗生素耐药性的传播对公众构成越来越大的威胁，因此需要新的抗菌策略。碳量子点（CQD）已被广泛研究以发挥荧光，催化作用，甚至具有杀菌作用的潜在生物医学功能。但是，仍然缺乏对CQD与细菌相互作用，抗菌能力的展现以及耐药性演变风险的综合理解。本文中，制造了一种简单的一锅法以制备带正电荷的CQD（PC-CQD）作为广谱抗菌剂。PC-CQD对所有测试的革兰氏阳性，革兰氏阴性和耐药菌具有有效的抗菌活性。₂和–NH诱导在细菌细胞膜上的强粘附行为。此外，PC-CQD的进入导致基因的构象变化和细菌中活性氧的产生。安全性评估表明，PC-CQD不会触发可检测到的耐药性或溶血现象。此外，PC-CQDs在体内毒性低的大鼠中有效地促进了金黄色葡萄球菌和大肠杆菌混合感染伤口的抗菌处理。这些结果表明，PC-CQD是在复杂细菌感染甚至耐药菌引起的感染中真正伤口愈合应用的潜在抗菌候选物。