Method for Quick Coomassie Blue Staining of Polyacrylamide Gels

Abstract

Gel electrophoresis is a popular technique that is taught in high school and college biotechnology laboratories. It can be used to demonstrate identification of proteins by analyzing banding patterns or it can be used for DNA analysis (Hames & Rickwood 1990; Carlson 1998). One drawback about this procedure, from a teaching perspective, is that it is time consuming and cannot be completed during a three-hour laboratory session. When using conventional procedures, the time period to run the mini-gel takes a minimum of 20 minutes at 250V (constant voltage). The Coomassie Blue staining procedure will take hours or overnight to see banding patterns with high resolution (Ballog 1991; Hames & Rickwood 1990). As a researcher, I used a nonconventional method of staining polyacrylamide mini-gels with Coomassie Blue when I analyzed the banding patterns of purified eukaryotic cell membrane proteins. This method can be applied to the community college biotechnology laboratories that use electrophoresis to separate human blood serum proteins, e.g. comparing sickle-cell anemia to normal hemoglobin (Kisiel 1980) or comparing blood serum of different animals to show evolutionary homology (Lewis 1998). A pure protein sample will show more distinct banding patterns and better resolution will be obtained when staining (Carlson 1998). The minimum protein concentration that can be analyzed using this quick Coomassie staining technique is 200 ng. This method is geared toward community colleges because some reagents used are hazardous; however when used properly, provide a quick, safe and convenient means of staining