Pluronic F-127-coated ZnO nanoparticles as superior photosensitizers for effective bladder cancer photodynamic therapy: In-vitro evaluation

Bladder cancer is the most prevalent malignancy of the urinary system and ranks among the top ten most common cancers in humans. Photodynamic therapy (PDT) demonstrates significant promise in cancer treatment due to its high selectivity and minimal side effects. Zinc oxide nanoparticles (ZnO NPs) exhibit substantial potential in various biomedical applications, including cancer therapy. This study systematically investigates the potential of bare and Pluronic F-127-coated ZnO NPs as photosensitizers (PSs) for effective photodynamic therapy against the RT4 bladder cancer cell line, marking the first such exploration. Transmission electron mi-croscopy (TEM) micrographs reveal the formation of a Pluronic F-127 coating layer with thickness ranging from approximately 3 nm-7 nm on the particle surface. The Pluronic coating process significantly enhances the cytotoxicity of ZnO NPs under dark conditions and during photodynamic therapy on the RT4 bladder cancer cell line. Additionally, the impact of PDT using bare and coated ZnO NPs is further evaluated through a 3D spheroid assay, which better replicates the real tumor environment for photodynamic therapy. Hoechst and rhodamine assays confirm the induction of apoptosis, characterized by nuclear condensation and disruption of mitochon-drial membrane potential in the cells. This study advances the potential of ZnO NPs in bladder cancer photo-dynamic therapy and highlights the importance of Pluronic F-127 coatings, paving the way for more effective and targeted cancer treatments.