Staining nucleic acids and proteins in electrophoresis gels

This review addresses the most widely used stains for gel electrophoresis in molecular biology today. A brief introduction to electrophoresis is given, followed by a description of agarose and acrylamide gel formation. The major stains for nucleic acids are described, most of which are fluorescent and intercalate into the double helix structure of the nucleic acids. An ultraviolet transilluminator is necessary to visualize the fluorescent bands. The major protein stains include Coomassie blue, silver, and commercial fluorescent stains. Negative staining also can be used to stain the gel background, leaving the protein bands of interest transparent and visible against a white background.