Iron as a Stain for Nucleic Acids in Electron Microscopy

Abstract

The use of iron (0.1 [image] FeCl3) as a stain for acidic residues for electron microscopy is described. Differential staining of protein and nucleic acid is demonstrated in the bacteriophage T2 of Escherichia coli, using OsO4 and FeCl3. Chemical analysis indicates a combining ratio of 4 atoms of iron to 1 atom of nucleic acid phosphorus.