A device for in vitro irradiation with alpha-particles using an alpha-emitting radioactive source

A device to irradiate a monolayer of cultured cells with alpha-particles using an Am-241 alpha-source (33.4 MBq) was designed to investigate RBEs of alpha-particles in cell killing, induction of chromosome aberration, mutagenic changes and transformation. This device can be used conveniently in a common laboratory by a small number of researchers without any limitation of machine time. The device performs as follows: (1) The energy of alpha-particles at the entrance of the cell layer is 3.20 MeV with a standard deviation of 0.25 MeV, (2) the incident angle to the cell layer is 82.8 degrees with a standard deviation of 3.2 degrees, (3) the fluence rate is 4.7 x 10(5) cm-2.min-1, (4) the average LET infinity for a cell layer 5 microns thick is 138 keV/micron, (5) the average dose rate for a cell layer 5 microns thick is 0.10 Gy/min., (6) a temperature and CO2 concentration conducive to cell cultivation are maintained during irradiation.