A novel and single step ultrastructural method for staining biological tissues embedded in common embedding media.

: A new single step staining method is described which is very simple, rapid and reproducible with better contrast than the widely employed uranyl acetate-lead citrate double staining method for observation of cell organelles in various tissue sections using transmission electron microscope. A copper uranyl acetate solution was employed to stain the ultrathin sections of tissues embedded in either water-miscible or water-immiscible resin media. The staining results are excellent. Cell organelles and extracellular matrix are stained with no artifactual precipitation or granulation.