Novel carbon dots (CDs) were synthesized by a one-pot hydrothermal approach using ampicillin as a precursor, and the as-prepared CDs exhibited a high quantum yield (23%). The CDs were found to possess abundant surface functional groups, thus providing good permeability to the cell, and the antibacterial activity of CDs was evaluated. S. aureus and L. monocytogenes were selected as model bacteria, and our results showed that the CDs exhibited antibacterial activity against S. aureus and L. monocytogenes under visible light illumination, even at low concentrations. The antibacterial mechanism is believed to be the production of reactive oxygen species (ROS) from CDs under visible light irradiation, which attacked the bacterial cell membranes, resulting in the death of the bacteria. In addition, because of the multicolor fluorescence properties of CDs, staining of S. aureus and L. monocytogenes obtained multicolor fluorescence images at different excitation wavelengths. Based on these results, CDs are a promising candidate material for biological applications. Graphical abstract.

中文翻译：

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碳点的一步合成，用于选择性细菌灭活和细菌分化。

以氨苄青霉素为前体，通过一锅水热法合成了新型碳点（CD），并且所制备的CD表现出较高的量子产率（23％）。发现CD具有丰富的表面官能团，从而为细胞提供了良好的渗透性，并评估了CD的抗菌活性。选择金黄色葡萄球菌和单核细胞增生李斯特菌作为模型细菌，我们的结果表明，即使在低浓度下，CD在可见光照射下也表现出对金黄色葡萄球菌和单核细胞增生李斯特菌的抗菌活性。据信这种抗菌机制是在可见光照射下从CD产生活性氧（ROS），它攻击细菌细胞膜，导致细菌死亡。此外，由于CD的多色荧光特性，金黄色葡萄球菌和单核细胞增生李斯特氏菌染色可在不同激发波长下获得多色荧光图像。基于这些结果，CD是用于生物应用的有前途的候选材料。图形概要。