Kobayashi Yasuhiko, Funayama Tomoo, Wada Seiichi, Sakashita Tetsuya
Research Group for Biotechnology Development, Japan Atomic Energy Research Institute (JAERI-Takasaki).
Biol Sci Space. 2003 Oct;17(3):253-4.
A single cell irradiation system has been developed at JAERI-Takasaki to elucidate biological effects of low dose and low dose-rate space radiation. The system has been installed at high-energy collimated heavy-ion microbeam apparatus under a vertical beam line of AVF-cyclotron accelerator. Individual mammalian cultured cells are irradiated in the atmosphere on the cell dish, the bottom of which is made of ion-track-detector TNF-1 (modified CR-39), with a single or precise numbers of 11.5 MeV/u 40Ar13+, 13.0 MeV/u 20Ne7+, and 18.3 MeV/u 12C5+ ions. Positional data of the target cells are obtained at the off-line microscope before irradiation. Targeting and irradiation of the cells are performed automatically at the on-line microscope of the microbeam apparatus according to the obtained data. About 50-100 cells are irradiated in several minutes. The number of ions traversed the cells attached on the ion track detector were counted with a plastic scintillator-photomultiplier tube assembly and a constant fraction discriminator. Immediately after the irradiation, the bottom of the cell dish was etched at 37 degrees C to check the spatial distribution of irradiated ions. The one batch of cell sample is treated in about 1 hr including the phases of cell finding, irradiation, and etching/observing of the ion tracks.
日本原子能研究开发机构高崎研究所开发了一种单细胞辐照系统，以阐明低剂量和低剂量率空间辐射的生物学效应。该系统已安装在AVF回旋加速器垂直束线下的高能准直重离子微束装置上。将单个哺乳动物培养细胞置于细胞培养皿的大气环境中进行辐照，培养皿底部由离子径迹探测器TNF-1（改良型CR-39）制成，用单个或精确数量的11.5 MeV/u的40Ar13+、13.0 MeV/u的20Ne7+和18.3 MeV/u的12C5+离子进行辐照。在辐照前，通过离线显微镜获取靶细胞的位置数据。根据获取的数据，在微束装置的在线显微镜上自动对细胞进行靶向和辐照。几分钟内对约50 - 100个细胞进行辐照。用塑料闪烁体 - 光电倍增管组件和恒比鉴别器对穿过附着在离子径迹探测器上细胞的离子数量进行计数。辐照后立即在37摄氏度下蚀刻细胞培养皿底部，以检查辐照离子的空间分布。一批细胞样品的处理过程，包括细胞寻找、辐照以及离子径迹蚀刻/观察阶段，大约需要1小时。
