Loss of Silver Grains from Radioautographs Stained by Gallocyanin-Chrome Alum

Abstract

Radioactive tissue sections covered with the film from Kodak Fine-Grain Autoradiographic Stripping Plate AR. 10 were stained with Ehrlich's hematoxylin or gallocyanin-chrome alum after exposure and photographic processing. Staining with gallocyanin-chrome alum at pH 1.7 and 2.4 dissolved the silver grains completely or almost completely in 1 to. Grains were quite visible after a 3 hr staining at pH 3.4, but a statistical analysis revealed a loss of grains, compared with unstained controls. Grains were also lost in slides immersed in solutions of gallocyanin alone at pH 2.5 for 24 hr but not in solutions of chrome alum alone, nor in some other alums. In sections stained 1 hr with Ehrlich's hematoxylin, the grains were not dissolved.