Laser-induced photodynamic effect

摘要

Photodynamic therapy is a treatment that is used for destruction of certain tumours. The treatment is performed with photosensitisers that generate reactive oxygen species in the presence of light and oxygen. The absorption and fluorescence spectra of the ClAlPcS_2 and ZnPcS_2 photosensitisers were measured. From this analysis a semiconductor laser emitting a beam of 50 m W cw power at the wavelength of 675 nm for our experiments was chosen, because this wavelength corresponded with the absorption maximum ( 675 nm ) in long-wave region of the visible part of electromagnetic spectra. B16 ( cells line of mouse melanoma ) was chosen as a standard testing system for definition of the in vitro phototoxicity after photodynamic reaction. The optimal phototoxic effect on B16 cells was observed at 2 μg/ml ClMPcS_2 in combination with laser irradiation of 10 J/cm~2.