A semi-automated technique for assessing the microdistribution of 239 Pu deposited in bone

A semi-automated analytical procedure is described for the localisation of 239 Pu in bone. The method is based on the use of a Quantimet 720B Image Analyser for the analysis of neutron-induced autoradiographs, and may be applied to most tissues with fissionable radionuclides. Compared with former methods the present technique offers improvements in accuracy and a considerable saving on time and manpower. These savings arise mainly from the ability of the Quantimet to be used for the automatic detection of the fission-fragment tracks and to operate directly on the neutron-induced autoradiograph without recourse to photography. Results are presented for the distribution of 239 Pu in the ilia of CBA mice at 24 h post-injection.