Silver staining is a common special staining technique used in medical laboratories. Gomori's Methenamine Silver (GMS) stain is used for fungi and bacteria. The fungi and bacteria are turned black, while everything else is stained green with Light green SF solution.

Using GMS stain, aldehydes resulting from oxidation of 1,2-glycols with periodic acid are visualized with a methenamine borate silver nitrate solution. The aldehyde groups reduce silver ions in the alkaline pH range to metallic silver, which appears black. The color of the silver deposits can be intensified still further by treatment with gold chloride solution, which forms a silver-gold complex. The use of gold chloride solution also prevents non-specific staining of the background. Excess silver nitrate is washed out with sodium thiosulfate solution.

The important step in Gomori's Methenamine Silver stain technique is carried out with the methenamine borate silver nitrate solution in a water bath at approx. 52°C for 35-45 min. The warmed staining solution gives brilliant and intense staining results. A detailed procedure is available on the insert sheet included in the staining kit.

If preferred, Gomori's Methenamine Silver stain technique can be performed in a microwave oven as well. A microwave protocol has been developed that specifies a contact time for the methenamine borate silver nitrate solution of 2 min only. The solution has to be radiated for 55 sec with 600 W beforehand. The microwave protocol is available on request.

The Methernamine silver plating acc. to Gomori kit guarantees easy silver staining and offers in addition:

• highly reproducible results
• perfect visualization of argentaffin structures
• the kit contains all of the reagents needed for the reaction
• the kit includes the methenamine borate component in handy tablet form
• simple, dependable procedure
• time-saving microwave protocol is available
• user-friendly pack size - kit with 100 ml PE bottles
• kit for 10 staining operations, for up to 50 stained slides in total
• developed, tested and produced in accordance with DIN ISO 9001