Revolutionary Pyrazole‐based Aza‐BODIPY: Harnessing Photothermal Power Against Cancer Cells and Bacteria

Abstract In the realm of cancer therapy and treatment of bacterial infection, photothermal therapy (PTT) stands out as a potential strategy. The challenge, however, is to create photothermal agents that can perform both imaging and PTT, a so‐called theranostic agent. Photothermal agents that absorb and emit in the near‐infrared region (750–900 nm) have recently received a lot of attention due to the extensive penetration of NIR light in biological tissues. In this study, we combined pyrazole with aza‐BODIPY ( PY ‐ AZB ) to develop a novel photothermal agent. PY ‐ AZB demonstrated great photostability with a photothermal conversion efficiency (PCE) of up to 33 %. Additionally, PY ‐ AZB can permeate cancer cells at a fast accumulation rate in less than 6 hours, according to the confocal images. Furthermore, in vitro photothermal therapy results showed that PY ‐ AZB effectively eliminated cancer cells by up to 70 %. Interestingly, PY ‐ AZB exhibited antibacterial activities against both gram‐negative bacteria, Escherichia coli 780, and gram‐positive bacteria, Staphylococcus aureus 1466. The results exhibit a satisfactory bactericidal effect against bacteria, with a killing efficiency of up to 100 % upon laser irradiation. As a result, PY ‐ AZB may provide a viable option for photothermal treatment.