Dual-functionalized carbon dots with precise antibacterial activity through specific recognition and enzyme inactivation.

The rise of drug-resistant bacteria, coupled with the toxicity of existing therapies, has underscored an urgent demand for novel, precise, and resistance-resistant antimicrobial agents. Carbon dots (CDs), an emerging class of carbon nanomaterials, offer a promising platform due to their excellent biocompatibility and tunable surface chemistry. In this study, we design and synthesize functional CDs capable of selective bacterial recognition coupled with potent antibacterial activity. These CDs were prepared from phytic acid (PA) and citric acid (CA) via electro-polymerization, which features dual functional characters: specific bacterial recognition and metal chelation. These CDs selectively penetrate bacterial, but not human skin cells, bind to and inactivate DNA polymerase I inside bacterial cells, exerting antibacterial action (IC50: 344.4 μg mL-1). Furthermore, a mathematical model was developed to elucidate the antibacterial mechanism of the CDs, offering deeper insight into their dynamic action. This work provides valuable insights for the functional design of CDs and advances the development of precise antibacterial therapies.