著者

平野 達

出版者

一般社団法人 レーザー学会

雑誌

レーザー研究 (ISSN:03870200)

巻号頁・発行日

vol.35, no.8, pp.486-492, 2007

被引用文献数

1

---

PDT is based on the generation of singlet oxygen (<SUP>1</SUP>O<SUB>2</SUB>) in a photochemical reaction among a tumor-accumulated photosensitizer, irradiation light, and oxygen in a tumor, and the detection of <SUP>1</SUP>O<SUB>2</SUB> is very important for understanding the mechanism of PDT. We used a near-infrared detection system to detect a 1270nm emission that was derived from the <SUP>1</SUP>O<SUB>2</SUB>. Utilizing this system, we detected the generation of <SUP>1</SUP>O<SUB>2</SUB> from Photofrin dissolved in water or injected in a HeLa tumor-bearing mouse. We showed the irradiation power dependence of the generation of <SUP>1</SUP>O<SUB>2</SUB> in 5-ALA-mediated PDT with 9L cells and 9L tumor-bearing rats. High-power irradiation reduced the generation of <SUP>1</SUP>O<SUB>2</SUB> more than that with low power, and an MTT assay revealed that more 9L cells were killed by low-powered irradiation. In tumors, low-powered irradiation resulted in efficient tumor necrosis. Generations of <SUP>1</SUP>O<SUB>2</SUB> in ICG and TiO<SUB>2</SUB> irradiation are also described.