Negative staining technique

Fig. 3. Negative stain technique. Micrograph shows a bundle of pili From the bacterium Neisseria meningitidis immunostained with an antipilus rabbit polyclonal antibody visualized using Protein A conjugated to 5-nm gold followed by negative staining with 1% methyl tungstate. Bar is 0.1 pm.

Negative staining Technique of staining the background around a specimen, leaving the specimen clear and unstained. 

Fig. 5.17. Electron micrograph, prepared by the negative staining technique, of a mixture of specifically purified rabbit anti-2,4-dinitrophenyl (anti-DNP) antibody and a bivalent hapten (see text). The length of a typical linear segment in one of the many closed structures is about 120 A. From Valentine and Green (7).

The negative-staining technique is of invaluable aid in determining the fine structure of very small objects in suspension, such as proteins (ferritin, catalase, enzymatic complexes, etc.), viruses or isolated subcellular elements (mitochondria, ribosomes membranes). It consists of placing the object in an electron-dense stain... 

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