Do these stains work like osmication or uranyl acetate staining?
These reagents work only on cells or macromolecules in suspension: a layer of electron-dense material is left around the edges of the cell or macromolecule, and the edges are defined. The spaces between the structures of interest are filled in rather than the features themselves; this makes negative staining particularly appropriate for use with immunogold labeling. There is no positive staining of the biological specimen itself, unlike osmication.
