BODIPY-based photosensitizers with simultaneous photodynamic antitumor and antibacterial effects

Abstract

Surgical positive margins and surgical site infections have seriously affected the prognosis of tumor resection. Photodynamic therapy is a promising candidate as adjuvant therapy to eliminate surgical positive margins and surgical site infections with minimal side effects and negligible drug resistance. Herein, we report BODIPY-based photosensitizers with photodynamic antitumor and antibacterial activity to improve the prognosis of postoperative patients. The photosensitizers bearing two pyridinium groups spontaneously self-assemble in water to form stable nanoparticles. The ¹O₂ generation efficiency of nano-PSs in water is 24–124 times higher than that of the corresponding molecules in organic solutions. Photodynamic experiments demonstrate that the nano-PSs target the mitochondria of cancer cells and induce cancer cell apoptosis under 660 nm light irradiation. Meanwhile, nano-PSs also kill clinically resistant Gram-positive bacteria upon light irradiation. The antibacterial activity is 128-fold higher than clinical antibiotics, norfloxacin. The excellent antitumor and antibacterial properties endow these nano-PSs with great potential to eliminate surgical positive margins and surgical site infections. This work provides a significant guideline for developing photosensitizers with excellent properties to improve the prognosis of tumor excision.