Whole-body autoradiography using 11C with double-tracer applications

This paper reports that it is possible to obtain good autoradiographic pictures of a 11C-labelled compound ([11C]methionine) in spite of the short half-life of 20 min by modifying the whole-body autoradiographic (WBA) technique. Double radionuclide autoradiography was performed by utilizing the great difference between the half-lives of 11C and 14C or 35S. The first exposure resulted entirely from 11C, and the second exposure the day after from 14C or 35S, respectively. Satisfactory blackening of the film was obtained by a mean radioactivity of 1.6 X 10(6) disintegrations/cm2 during the exposure. The 11C-WBA technique apparently provides a useful tool in distribution studies on animals, which is valuable in the interpretation of positron emission tomography images of the same 11C-compound.