Vancomycin-Biomineralized Gold Nanoflowers for In Vitro Photothermal Antibacterial and Antitumor Applications

Photothermal therapy is a highly promising non-invasive treatment strategy, but its clinical application is still limited by issues such as insufficient light-to-heat conversion efficiency and potential biological toxicity. To address these challenges, this study employed a biomineralization strategy to synthesize gold nanoflowers (Van@Au4 NFs) using vancomycin as a template. The synthesized Van@Au4 NFs exhibited a uniform flower-like morphology with a hydrodynamic diameter of approximately 122 nm. Under 808 nm laser irradiation, this material demonstrated excellent photothermal properties, with a photothermal conversion efficiency of 34.94%, and remained stable after four cold-hot cycles. The introduction of vancomycin effectively enhanced the colloidal stability and photothermal conversion ability of the nanoflowers. In vitro experiments showed that Van@Au4 NFs had an inhibition rate of 90.8% against Staphylococcus aureus and 95.18% against A549 tumor cells under near-infrared light irradiation. This study constructed an efficient photothermal agent, providing important experimental evidence for in vitro synergistic photothermal treatment of bacterial infections and tumors.