Local photothermal/photodynamic synergistic antibacterial therapy based on two-dimensional BP@CQDs triggered by single NIR light source.

Pathogenic bacteria-infected wound healing faces challenges even though many advanced antibiotics and antibacterial nanoagents have been developed. Herein, we established a two-dimensional antibacterial nanoplatform with synergistic photothermal therapy (PTT) and photodynamic therapy (PDT) antibacterial capabilities mediated by a single 808 nm laser irradiation. The nanoplatform is constructed by combining black phosphorus (BP) obtained by liquid phase exfoliation and hydrothermally prepared tellurium-doped carbon quantum dots (CQDs) prepared by electrostatic interaction. As a result, the photothermal conversion of BP and hydroxyl radical (‧OH) production of CQDs under NIR laser makes the nanoplatform (BP@CQDs) possess an outstanding antibacterial performance against S. aureus and E. coli (as high as 92.7% and 98.4%, respectively), resulting in a faster wound closure ratio than another infected wound. Moreover, in vitro and in vivo researches showed that BP@CQDs have good hemocompatibility, cytocompatibility, and biocompatibility during the therapeutic process. This work demonstrates the broad application prospect of BP nanosheets in infectious microenvironments and develops a potential strategy for S. aureus-infected wound repair.

Dual enzyme-mimic nanozyme based on single-atom construction strategy for photothermal-augmented nanocatalytic therapy in the second near-infrared biowindow.

Nanozyme-based catalytic therapy, an emerging therapeutic pattern, has significantly incorporated in the advancement of tumor therapy by generating lethal reactive oxygen species. Nevertheless, most of the nanozymes have mono catalytic performances with H2O2 in the tumor microenvironment (TME), which lowers their therapeutic efficiency. Herein, we design a newly-developed single-atom Fe dispersed N-doped mesoporous carbon nanospheres (SAFe-NMCNs) nanozyme with high H2O2 affinity for photothermal-augmented nanocatalytic therapy. The SAFe-NMCNs nanozyme possesses dual enzyme-mimic catalytic activity which not only acts as a catalase-mimic role to achieve ultrasonic imaging in tumor site by O2 generation, but also exhibits the superior peroxidase-mimic catalytic performance to generate •OH for nanocatalytic therapy. Besides, the SAFe-NMCNs nanozyme with strong optical absorption in the second near-infrared (NIR-II) region shows excellent photothermal conversion performance. The peroxidase-mimic catalytic process of SAFe-NMCNs nanozyme is realized using density functional theory (DFT). Both in vitro and in vivo results indicate that the SAFe-NMCNs nanozyme can efficiently suppress tumor cells growth by a synergistic therapy effect with photothermal-augmented nanocatalytic therapy. The work developed a single-atom-coordinated nanozyme with dual-enzyme catalytic performance and achieve hyperthermia-augmented nanocatalytic therapy effect, can open a window for potential biological applications.