Abstract

The new photosensitizer (PH-1126) is a pheophorubaide derivative which have amine in the D-ring of pheophorubaide structure. This photosensitizer have the longest absorbance peak of Q band at 652.4nm. Comparing PH-1126 and HpD in terms of the longest absorbance peak of Q band, the wavelength of PH-1126 is 35nm longer. Its longest absorbance peak of Q band showed the 7.5 times than the HpD's at same concentration. Since blood (hemogrobin) and tissues absorbs light in the 500-600nm wavelength range, light transmittance is low in this range. Longer wavelength, especially those greater than 600nm, are not affection by the blood and tissues. The effect of the PH-1126 and red light at 647.1nm wavelength of Kr'-laser on Meth-A tumors transplanted in mice was examind. The animals were given a oral administration of PH-1126 in doses range of 0-40mg/kg b. w.. At 48hrs after administration, Kr⁺-laser were irradiated with laser power of 50mw/cm2 and power density of 0-60J/cm2. In the experimental animals, tumor mass with PH-1126 in doses of 40mg/kg b. w. and laser Power density of 60J/cm2 were 11.4% to non-treatment tumor mass at 7days after PDT.