title: An improved procedure for the X-ray microanalysis of acid phosphatase activity in lysosomes.
abstract: The useful detection of acid phosphatase activity with cerium as a capturing agent is confirmed. By introducing a freeze step in combination with a preincubation, reliably localized, lysosomal precipitates are obtained and aspecific ones prevented. Short (t less than 1 h) postfixation with either OsO4 plus K4Fe (CN)6 or OsO4 plus aminotriazole, added to lysosomal cerium localization a high membrane contrast. The detection of cerium by X-ray microanalysis is improved by a better spectral separation of the osmium (M alpha) and cerium (L alpha) peaks.
mesh_terms: D000135:Acid Phosphatase / Q000032:analysis*; D000818:Animals; D002563:Cerium; D004121:Dimethyl Sulfoxide; D004577:Electron Probe Microanalysis; D005615:Freezing; D006651:Histocytochemistry; D007687:Kidney Tubules, Proximal / Q000648:ultrastructure; D008247:Lysosomes / Q000201:enzymology*; D008264:Macrophages; D051379:Mice; D009993:Osmium Tetroxide; D010539:Permeability; D051381:Rats
chemical_list: D002563:Cerium; D000135:Acid Phosphatase; D009993:Osmium Tetroxide; D004121:Dimethyl Sulfoxide