Abstract
Hematoporphyrin studies including absorption and fluorescence measurements were performed using hematoporphyrin dihydrochloride (Hp. 2HCl) dissolved in ethanol and PBS solutions. Q-switched Nd: YAG laser original and its second harmonic beam were employed for their excitation. Thus the visible fluorescence generated by Nd: YAG laser irradiation was attributed to the two-photon absorption process in these solutions, although its intensity was about 10-4 weaker than the case of second harmonic excitation. Survival rate of TE-2 cultured esophagus cancer cell uptaken Hp. 2HCl exhibited a linear decrease with the Nd: YAG laser irradiation time, and this photochemical effect was formed to be more appreciable for higher dye concentration.
