A new photosensitizer sulfonated aluminum phthalocyanine:In vitro study on its photodynamic action

Abstract

The photosensitizing effects of sulfonated aluminum phthalocyanine on human liver cancer cells were studied by determining the kinetics of its cellular uptake, its state of aggregation therein and its photocytotoxicitic effect on these cells. Fluorescence methods were used to measure the cellular uptake in cell extracts and intact cells in monolayer. Results exhibited that the cellular uptake increases with the incubation time of sulfonated aluminum phthalocyanine (Alspc) and saturates at 24 hours. This relation was in coincidence with that between Alspc’s photocytotoxic effect and the Alspc incubation time. Although the average Alspc concentration in cells is higher than the incubation concentration of Alspc, laser fluorescence experiments showed that the fluorescence peak of Alspc in cells incubated in higher concentration coincides with that of its aqueous solution of low concentration, suggesting that Alspc in cancer cells exists in monomer state. The results that lipid peroxidation in cells is enhanced by Alspc photosensitization reflected that it may be one of the mechanisms of cell damage. The photodamage on cells was also studied with 3T3 mouse cells (conversion), showing agreeable results to that with liver cancer cells, which suggests that Alspc’s photocytotoxic effect is nonselective to cell types.