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