Silver stain development

Cassab GI, Varner JE. Immunocytolocalization of extensin in developing soybean seed coats by immunogold-silver staining and by tissue printing on nitrocellulose paper. J Cell Biol 1987 105 2581-2588. 

There are a number of different silver staining methods. Some are available in kit form from various manufacturers. Others do not lend themselves to commercial kits. For a discussion of the mechanisms of silver staining, see Reference 54. Silver staining can be as much as 100 times more sensitive than CBB dye staining. All silver staining procedures have many manual steps and the decision as to when to terminate color development is quite subjective. 

In silver staining, the gel is Impregnated with soluble silver ions and developed by treatment with formaldehyde, which reduces silver ions to form an insoluble brown precipitate of metallic silver. This reduction is promoted by protein. 

A variety of methods are available to detect proteins separated by electrophoresis or to measure the concentration of total protein in a solution. These methods are normally based on the binding of a dye to one of the amino acids in protein, or a color reaction with an amino acid side chain. The most commonly used stains for protein detection on gels are Coomassie Brilliant Blue (98) and silver stain (99,100). These methods detect any protein residues, either in solution or on an electrophoresis gel. Their main requirement is sensitivity, not specificity. New, more sensitive dyes are being developed for the proteomic analysis of protein structure and sequence, for example Ruby Red (101). 

Scan the ECL-developed film, the Ponceau S-stained nitrocellulose membrane, and the silver-stained gel of the same sample with a computing densitometer with a sufficient resolution (see Notes 24 and 25). 

Uses In acidulating and preserving fixing baths as a preservative for pyro developer for removing silver stains from printing-out paper. 

Second, methods for the characterization of complex antisera are difficult. Antisera to E. coli protein mixtures have been developed with impressive spectra of reactivity using conventional immunization methods (6,22-23). An exact assessment of the spectrum of antibody reactivity is often limited, however, by the resolution of the analytical methods used. Counter immunoelectrophoresis is limited by the relatively low sensitivity of detection and resolution for complex mixtures of reacting species. One dimensional silver stained SDS-PAGE and immunoblotting provides sensitive detection limits but lacks resolution. Therefore, methods which have a high degree of resolution and sensitivity are required to best compare potential improvements in the production of antibodies to minor components in the mixture. 

Improved silver staining procedure for fast staining in PhastSystem Development Unit. 1. Staining of sodium dodecyl sulfate gels. Electrophoresis 9,... 

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