• M. Uesaka
  The University of Tokyo, Nuclear Professional School, Ibaraki-ken
• R. Kuroda, K. Yamada
  AIST, Tsukuba, Ibaraki
• K. Mizuno, A. Mori, T. Natsui, H. Taguchi, J.D. Trono
  University of Tokyo, Tokyo
• N. Yusa
  Tohoku University, Graduate School of Engineering, Sendai

In X-ray Drug Delivery System, anticancer drugs containing Pt, such as cisplatin and dachplatin, and Au colloid contrast agent are surrounded by polymers (micelle, PEG (polyethylene glycol), etc.).Ttheir sizes are controlled to be 20-100 nm. Since holes of capillary to organ are as large as 100 nm in only cancer, those large particles can be accumulated in cancer effectively. That is called as EPR (Extended Penetration and Retention effect). We have observed the distribution of Pt of dachplatin-micelle in cancer of mouse’s pancreas by X-ray fluorescence analysis using 10 μm pinpoint 15 keV X-ray by SPring8. Further, in-vitro- and in-vivo-experiments of Au colloid PEG are under way. It is expected to be used as contrast agent for dynamic tracking treatment for moving cancer. Imaging properties for polychromatic X-rays from X-ray tube and monochromatic Compton source are numerically analyzed and discussed. We continue to analyze radiation enhancement by Auger electrons and successive characteristic X-rays and its toxic effect to cancer.

• N. Fukunishi, T. Dantsuka, M. Fujimaki, A. Goto, H. Hasebe, Y. Higurashi, E. Ikezawa, T. Kageyama, O. Kamigaito, M. Kase, M. Kidera, M. Komiyama, H. Kuboki, K. Kumagai, T. Maie, M. Nagase, T. Nakagawa, J. Ohnishi, H. Okuno, N. Sakamoto, Y. Sato, K. Sekiguchi, K. Suda, H. Suzuki, M. Wakasugi, H. Watanabe, T. Watanabe, Y. Watanabe, K. Yamada, Y. Yano, S. Yokouchi
  RIKEN Nishina Center, Wako

The RIKEN RI Beam Factory (RIBF) is pushing the limits of energy for heavy ion cyclotrons. The first experiment of the RIBF has successfully finished with the discovery of new isotopes ¹²⁵Pd and ¹²⁶Pd* in June 2007 with a 345-MeV/nucleon uranium beam. However, the total transmission efficiency was limited to be less than 1%. In addition, a carry-over of oil was found in the refrigerator of the Superconducting Ring Cyclotron (SRC), which was the main accelerator of the RIBF. To solve these problems, we have improved beam monitors, upgraded the oil remover system of the compressor of the liquid helium cryogenic plant at SRC and made a series of acceleration tests. As a result, 0.3 pnA of a 345-MeV/nucleon uranium beam was stably delivered to RIBF users in November 2008 and a 345-MeV/nucleon ⁴⁸Ca beam with the intensity of 170 pnA was obtained in December 2008. In the PAC09 presentation, we will summarize our operating experience with the SRC and developments of RIBF accelerators in addition to most up-to-date performance of the RIBF accelerator complex.

*T. Ohnishi et al., J. Phys. Soc. Jpn. 77 (2008) 083201

Slides