title: Rapid localization of carbon 14-labeled molecules in biological samples by ion mass microscopy.
abstract: We report here on the ability of secondary ion mass spectrometry (SIMS) to provide rapid imaging of the intracellular distribution of 14C-labeled molecules. The validity of this method, using mass discrimination of carbon 14 atoms, was assessed by imaging the distribution of two molecules of well-known metabolism, [14C]-thymidine and [14C]-uridine, incorporated by human fibroblasts in culture. As expected, 14C ion images showed the presence of [14C]-thymidine in the nucleus of dividing cells, whereas [14C]-uridine was present in the cytoplasm as well as the nucleus of all cells, with a large concentration in the nucleoli. The time required to obtain the distribution images with the SMI 300 microscope was less than 6 min, whereas microautoradiography, the classical method for mapping the tissue distribution of 14C-labeled molecules, usually requires exposure times of several months. Secondary ion mass spectrometry using in situ mass discrimination is proposed here as a very sensitive method which permits rapid imaging of the subcellular distribution of molecules labeled with carbon 14.
authors.affiliation: Laboratoire de Biophysique, SC 27 de l'INSERM, Faculté de Médecine, Créteil, France.
authors.forename: E
authors.initials: E
authors.lastname: Hindie
authors.forename: F
authors.initials: F
authors.lastname: Escaig
authors.forename: B
authors.initials: B
authors.lastname: Coulomb
authors.forename: C
authors.initials: C
authors.lastname: Lebreton
authors.forename: P
authors.initials: P
authors.lastname: Galle
mesh_terms: D002250:Carbon Radioisotopes / Q000032:analysis*; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*; D008853:Microscopy / Q000379:methods*
chemical_list: D002250:Carbon Radioisotopes