Nitrogen-doped carbon dots/curcumin nanocomposite for combined Photodynamic/photothermal dual-mode antibacterial therapy

Due to their excellent photophysical properties, carbon quantum dots have great potential in biomedical and drug delivery fields. In this study, nitrogen-doped carbon quantum dots with good water solubility were prepared using citric acid and ethylenediamine as precursors, and compounded with curcumin, a photosensitive component, to produce composite nanomaterials with photodynamic therapy and synergistic photothermal therapy. The formation of nitrogen-doped carbon quantum dots and composite nanomaterials was verified using physical and optical means. In addition, the composite nanomaterials produced single-linear oxygen and exac-erbated the increase of solution temperature under blue (405 nm) and near-infrared (808 nm) light irradiation, respectively. The plate counting method showed that the composite nanomaterials exhibited good photodynamic synergistic photothermal antibacterial properties against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus under dual light source (405+808 nm) irradiation, which improved the photoinactivation of curcumin against bacteria. In addition, the composite nanomaterials exhibited low toxicity and good hemo-compatibility. These experimental results suggested that the composite nanomaterials showed great potential in a multimodal photodynamic therapy synergistic photothermal treatment platform.

Automated summary

This study successfully prepared nitrogen-doped carbon quantum dots with good water solubility and compounded them with curcumin to produce composite nanomaterials with potential applications in photodynamic therapy and photothermal therapy. The formation of nitrogen-doped carbon quantum dots and composite nanomaterials was confirmed, and the composite nanomaterials exhibited good antibacterial properties under dual light source irradiation, as well as low toxicity and good hemo-compatibility.