Circularly polarized light activated chiral molybdenum-doped carbon dots for spatiotemporally synergistic antibacterial strategy
Chiral nanomaterials have attracted considerable attention for antibacterial applications due to their unique chiroptical properties. Here, we report a novel spatiotemporally precise synergistic photodynamic therapy (PDT) and photothermal therapy (PTT) strategy using circularly polarized light (CPL)-activated chiral molybdenum-doped carbon dots (L-Mo-CDs and D-Mo-CDs). These chiral carbon dots were synthesized using chiral tartaric acid as a precursor. Notably, D-Mo-CDs selectively respond to left-handed CPL (LCP), while L-Mo-CDs respond to right-handed CPL (RCP). Under CPL irradiation, D-Mo-CDs exhibit enhanced reactive oxygen species (ROS) generation and a higher photothermal conversion efficiency (PCE) compared to L-Mo-CDs. In vitro antibacterial assays demonstrate that D-Mo-CDs possess excellent bactericidal efficacy against both Gram-positive and Gram-negative bacteria. In vivo wound healing studies in a mouse model reveal remarkable therapeutic efficacy, attributed to reduced inflammation, accelerated angiogenesis, and enhanced collagen deposition. This work introduces a paradigm for utilizing chiral carbon dots in precision antibacterial therapy, addressing the limitations of conventional chiral nanomaterials such as poor biocompatibility and low photothermal conversion. The findings underscore the potential of metal-doped chiral carbon dots for advanced biomedical applications, offering a spatiotemporally controllable approach to combat bacterial infections without promoting resistance.