Silver Staining Kit is an extremely sensitive color-imetric staining procedure for the detection of subnanogram amounts of proteins resolved on polyacrylamide gels. With high sensitivity and very low background, Silver Staining Kit is ideal for the visualization of protein bands in dilute samples or for the detection of proteins present in trace amounts. It is generally about 100 fold more sensitive than the commonly used Coomassie Blue stain.The 4 hour staining procedure begins with a fixation step to reduce band diffusion and remove interfering substances. A sensitization process, which enhances binding of silver ions to proteins, follows fixation. The staining step allows silver ions to permeate the gel and bind preferentially to sulfhydryl and carboxyl side chains. In the final development step,silver ions are reduced to metallic silver to form precipitates that are visible as brown bands within the gel. Staining intensity varies by the type of protein in the sample. Acidic proteins and proteins with highly negatively charged sulfated sugar residues such as proteoglycans and mucins are not readily detected by silver stains.