The Photophysical Properties of Pyropheophorbide-a in Different Laser Light and PDT Efficiency for Eca-109 Cell In Vitro

Pyropheophorbid-a (PyroPheo) is one of the well-known photosensitizers which can be useful for future clinical applications. This work is aimed to compare and measure generation rates of single oxygen through activation of pyropheophorbide-a by four different wavelength, and observe the sensitivity of pyropheophorbide-a mediated photodynamic therapy for eca-109 cell. Methods: UV-vis spectrophotometrics was used to measure decrease of singlet oxygen probe 9,10-dimethylanthracene(DPBF) so as to evaluate singlet oxygen production generation. The Eca-109 cells were were exposed to light (650nm) with a constant light power of 200mW/cm2, at a distance of 5cm, for 25 to 200 seconds. The results were measured by MTT assay. Results: pyropheophorbide-a in DMF solution irradiation by different light power can produce singlet oxygen quickly. Comparison of single oxygen generation rate has proved that photodynamic effect at 532nm is fastest, followed by 650nm, 635nm, 690nm which has correlation with absorbance of pyropheophorbide-a. The survival rate of cells dropped after irradiation by light what was significantly different from other groups. Conclusion: pyropheophorbide-a is an excellent photosensitizer and prooxidant. Through activated by different wavelength it could be apply to different disease