Silverman L, Glick D
J Cell Biol. 1969 Mar;40(3):761-7. doi: 10.1083/jcb.40.3.761.
After aldehyde-fixation, treatment with phosphotungstic acid (PTA) in aqueous acidic medium was shown to produce an intense electron-opaque stain with minimal distortion of organelles. Mitochondrial matrix, cisternae of the endoplasmic reticulum, and the Z-band of muscle were densely stained, whereas membranes stood out in negative contrast. Staining of glycogen or lipid was not apparent. Under certain conditions the stain density reflected the concentration of protein based on the quantitative reaction of PTA with the positively charged groups, although the stoichiometry of the reaction between PTA and protein varied with the kind of protein. The staining conditions established should provide a base for the use of the method in quantitative electron microscopy, particularly on thin sections.
醛固定后，在水相酸性介质中用磷钨酸（PTA）处理，结果显示能产生强烈的电子不透明染色，且细胞器变形最小。线粒体基质、内质网池和肌肉的Z带被密集染色，而膜则呈现负反差。糖原或脂质的染色不明显。在某些条件下，基于PTA与带正电荷基团的定量反应，染色密度反映了蛋白质的浓度，尽管PTA与蛋白质之间反应的化学计量比因蛋白质种类而异。所建立的染色条件应为该方法在定量电子显微镜中的应用提供基础，特别是在薄片上的应用。
