@misc{oai:repo.qst.go.jp:00070000,
 author = {Matsumoto, Kenichiro and Aoki, Ichio and Nakanishi, Ikuo and Matsumoto, Atsuko and Nyuui, Minako and Endo, Kazutoyo and Anzai, Kazunori and 松本 謙一郎 and 青木 伊知男 and 中西 郁夫 and 松本 厚子 and 乳井 美奈子 and 安西 和紀},
 month = {Dec},
 note = {The spatial distribution of hydrogen peroxide (H2O2) generated in a solid gelatin sample irradiated by heavy-ion (carbon) beam was investigated. 
The detectable level of H2O2 was generated in water by relatively high-dose (~ 256 Gy) X-ray irradiation. Simultaneously, oxygen consumption was observed in water irradiated by X-ray. H2O2 generated in an aqueous solution of a nitroxyl radical, 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPOL), participated a reducing the nitroxyl radical during X-ray irradiation, since this reduction of nitroxyl radical was inhibited by catalase. H2O2 generation in the solid gelatin sample irradiated by carbon beam was analyzed using this reaction system.
An aqueous solution of a nitroxyl radical, TEMPOL, was caked using gelatin to test depth-dependent redox reactions. The gelatin sample was irradiated with a 290 MeV/nucleon carbon ion beam up to a dose of 128 Gy. The detection of H2O2 in a sample irradiated by a carbon beam was performed by EPR spectroscopic and MRI methods. When gelatin samples were irradiated by several different linear energy transfer (LET) of carbon beam, the H2O2 generation profile in the gelatin sample was obtained based on H2O2-dependent EPR signal loss of TEMPOL in the sample. The oxygen consumption profile in the gelatin sample, measured with L-band EPR oxymetry, showed almost the same shape as the H2O2 profile. The H2O2 profile in one intact solid gelatin sample scanned by 7 T MRI showed a similar shape as a result of the EPR experiment. Micromolar level generation of H2O2 in a gelatin sample irradiated by carbon beam was observed from the surface to the beam end with an almost flat distribution, except for a slight peak just before the beam end. 
The MRI approach using nitroxyl based redox transformations shows feasibility of obtaining spatial profiles of H2O2 generation in a solid sample irradiated with high LET radiation., 5th Joint Meeting of The Societies for Free Radical Research Australasia and Japan},
 title = {Visualizing distribution of hydrogen peroxidein an aqueous gelatin sample irradiated by carbon ion beam},
 year = {2009}
}