Low LET proton microbeam to understand high-LET RBE by shaping spatial dose distribution
Collection title:
Proceedings of the 15th International Conference on Nuclear Microprobe Technology and Applications
Journal:
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
Volume:
404
Issue:
Supplement C
Conference title:
International Conference on Nuclear Microprobe Technology and Applications (15., 2017, Lanzhou)
Venue:
Lanzhou, China
Year of conference:
2017
Date of conference beginning:
31.07.2017
Date of conference ending:
05.08.2017
Year:
2017
Pages from - to:
155-161
Language:
Englisch
Keywords:
Proton microbeam ; LET ; Spatial dose distribution ; RBE ; Fluorescent nuclear track detector
Abstract:
High LET radiation, like heavy ions, are known to have a higher biological effectiveness (RBE) compared to low LET radiation, like X- or -rays. Theories and models attribute these higher effectiveness mostly to their extremely inhomogeneous dose deposition, which is concentrated in only a few micron sized spots. At the ion microprobe SNAKE, low LET 20 MeV protons (LET in water of 2.6 keV/μm) can be applied to cells either randomly distributed or focused to submicron spots, approximating heavy ion dose deposition. Thus, the transition between low and high LET energy deposition is experimentally accessible and the effect of different spatial dose distributions can be analysed. Here, we report on the technical setup to cultivate and irradiate 104 cells with submicron spots of low LET protons to measure cell survival in unstained cells. In addition we have taken special care to characterise the beam spot of the 20 MeV proton microbeam with fluorescent nuclear track detectors. «
High LET radiation, like heavy ions, are known to have a higher biological effectiveness (RBE) compared to low LET radiation, like X- or -rays. Theories and models attribute these higher effectiveness mostly to their extremely inhomogeneous dose deposition, which is concentrated in only a few micron sized spots. At the ion microprobe SNAKE, low LET 20 MeV protons (LET in water of 2.6 keV/μm) can be applied to cells either randomly distributed or focused to submicron spots, approximating heavy io... »