Lead-Ammonium Acetate; A Staining Medium for Electron Microscopy Free of Contamination by Carbonate

Abstract
A solution which is stable toward atmospheric CO2 can be made by dissolving 18 gm of NH4Ac in 100 ml of a saturated solution of PbOAc2. Ultrathin sections stained for 45 min in the solution remain free of contamination by precipitated carbonate and show good contrast. No precautions to avoid contact with air need be taken during staining, filtration or storage. The pH of the solution is about 6.8.