Secondary ion images of the rodent brain

Sections of biologic tissue obtained from laboratory rodents are prepared a nd analyzed by secondary ion mass spectrometry. The intensity of phosphocho line secondary ions is used to identify anatomical features of the brain fr om secondary ion images and to evaluate the effectiveness of procedures dev eloped. Secondary ion emission of phosphocholine (m/z 184), is found to be abundant and its intensity is heterogeneous. Effects of sample thickness ar e addressed. Correspondence between conventional optical images of stained tissue and secondary ion images shows that successive ion images may be use d to produce a three-dimensional map of the brain, i.e., an atlas. (C) 2000 American Society for Mass Spectrometry.