Triplet-state photophysics of aluminium phthalocyanine sensitizer in murine cancer cells

Diffuse-reflectance laser flash photolysis has been used to record transient spectra and decay kinetics of the photodynamic therapy sensitizer dusulfonated aluminium phthalocyanine in two murine cancer cell lines, P815 derived from white mouse mast cells, and EL4, a lymphoblast derived from black mouse lymphocytes. In contrast to results with bacterial cells and yeasts, no transient other than the triplet state of the sensitizer was detected, suggesting that unlike the case in microbes, Type I electron-transfer processes play no role in the photodestruction of the murine cells studied.