title: Tissue localization of stable and radioactive nuclides by secondary-ion microscopy.
abstract: Images of the distribution of a given nuclide in a section of biological tissue can be obtained at the microscopic level by "secondary-ion mass analysis." In this method, the images are formed by an ion-emission microscope wherein the specimen's atoms are progressively sputtered from the surface and the ions are selectively visualized by mass spectrometry according to their mass-to-charge ratios. Such images are obtained at the cost of the destruction of the specimen, which is progressively eroded at the rate of 1-10 atomic layers per second. The spatial resolution is better than 1 micrometer for an imaged area 250 micrometer in diameter and a section thickness of 1-2000 nm; thus, the analytical images are element distributions representative of 3-6000 atomic layers. Distributional images can be obtained for many nuclides, whether stable or radioactive, natural or artificially administered.
mesh_terms: D000535:Aluminum / Q000032:analysis; D000818:Animals; D001706:Biopsy; D001842:Bone and Bones / Q000032:analysis*; D002118:Calcium / Q000032:analysis; D002414:Cations, Monovalent / Q000032:analysis; D004912:Erythrocytes / Q000032:analysis; D005069:Evaluation Studies as Topic; D005708:Gallium / Q000008:administration & dosage / Q000032:analysis; D006801:Humans; D007204:Indium / Q000008:administration & dosage / Q000032:analysis; D007668:Kidney / Q000032:analysis; D008854:Microscopy, Electron / Q000295:instrumentation / Q000379:methods*; D010018:Osteomalacia / Q000378:metabolism*; D051381:Rats; D012964:Sodium / Q000032:analysis
chemical_list: D002414:Cations, Monovalent; D007204:Indium; D012964:Sodium; D005708:Gallium; D000535:Aluminum; D002118:Calcium