Three-Pronged Flower-like Nanoplatforms for the Photothermal/Photodynamic/Quaternary Ammonium Salt Synergistic Antibacterial Method and Bioimaging

Bacterialinfections caused by pathogenic bacteria areextremelythreatening to human health. Currently, the treatment of bacterialinfections relies heavily on antibiotics, leading to a high incidenceof antibiotic abuse. Bacterial resistance appeared along with themisuse of antibiotics that produced growing harm to human beings.Therefore, a cutting-edge strategy for treating bacterial infectionsis indeed needed. Here we prepared QCuRCDs@BMoS2 nanocomposites(QBs) for an efficient bacterial trapping and triple quaternary ammoniumsalt/photothermal/photodynamic bactericidal method. Copper-doped carbonquantum dots were first prepared by using a solvothermal method, modifiedwith quaternary ammonium salts, and then combined with grafted MoS2 nanoflowers. The long alkyl chains of QBs and the sharp surfaceof MoS2 facilitate the destruction of bacterial structures,while the electrostatic adsorption binds closely to bacteria, shorteningthe bactericidal distance of the reactive oxygen species (ROS). Moreover,the excellent photothermal performance under 808 nm irradiation inthe near-infrared (NIR) region and deep penetrating heat can accelerateoxidative stress and achieve a multisynergistic bactericidal purpose.Consequently, QBs with ideal antibacterial properties and inherentbrightness hold great promise in the biomedical field.