Study of the stabilization of zinc phthalocyanine in sol-gel TiO₂ for photodynamic therapy applications

Abstract 

Photodynamic therapy (PDT) has emerged as an alternative and promising noninvasive treatment for cancer. It is a two-step procedure that uses a combination of molecular oxygen, visible light, and photosensitizer (PS) agents; phthalocyanine (Pc) was supported over titanium oxide but has not yet been used for cell inactivation. Zinc phthalocyanine (ZnPc) molecules were incorporated into the porous network of titanium dioxide (TiO₂) using the sol-gel method. It was prepared from stock solutions of ZnPc and TiO₂. ZnPc-TiO₂ was tested with four cancer cell lines. The characterization of supported ZnPc showed that phthalocyanine is linked by the N-pyrrole to the support and is stable up to 250°C, leading to testing for PDT. The preferential localization in target organelles such as mitochondria or lysosomes could determine the cell death mechanism after PDT. The results suggest that nanoparticulated TiO₂ sensitized with ZnPc is an excellent candidate as sensitizer in PDT against cancer and infectious diseases.

From the Clinical Editor

Photodynamic therapy is a two-step procedure that uses a combination of molecular oxygen, visible light and photosensitizer agents as an alternative and promising non-invasive treatment for cancer. The results of this study suggest that nanoparticulated TiO₂ sensitized with ZnPc is an excellent photosensitizer candidate against cancer and infectious diseases.

Key words: Titania, Phthalocyanine, Cancer, Photodynamic therapies