Polyacrylamide gel electrophoresis (PAGE) is a common laboratory technique for the separation and analysis of proteins. Unfortunately, the staining of proteins following PAGE separation can be a time-consuming process. The Gelcode Blue Stain Reagent by Pierce is an affordable, ready-to-use method that effectively cuts down on the time involved for fixing, staining and de-staining gels. It is a single reagent formulation, requiring the addition of only deionized water for both the fixing and de-staining steps. Moreover, Gelcode Blue Stain demonstrates versatility for use in staining NATIVE and SDS-PAGE gels, blotting membranes, as well as compatibility with different electrophoresis buffer formulations.
Gelcode Blue Stain exhibits a reduced level of band color intensity when compared to standard Coomassie protocols and reagents despite having the same colloidal properties as G-250 protein dyes. However, the lack in intensity is compensated for with an appreciable, albeit slight, increase in sensitivity. In addition, there is some flexibility in the protocol, such as the suggested number of washes and the staining incubation period. Detection can be quite rapid with distinct bands (corresponding to ~1-10 ug) appearing within approximately 30 mins on 0.75 mm gels. Staining overnight is also an option, requiring a minimum 2 hour “Water-Wash Enhancement” step the next day to effectively remove any background. In fact, there is no possibility of over-destaining since the gels can be stored in deionized water. The Pierce formulation retains the stain color intensity over longer periods of time (5-months) than other staining techniques, with little fading; a fact observed when using single-step formulations from other companies.
To maximize the staining capabilities, wash the gel with at least 100 ml of deionized water (for at least 5-7 mins per wash and a minimum of two changes), use thinner gels (< 1 mm) and equilibrate the Gelcode bottle to room temperature prior to incubation. While there are other options available, the Gelcode Blue Stain Reagent’s low-cost, ease of use and consistent results has made it a mainstay in our laboratory.
Rhoel Dinglasan, Ph.D., MPH
Postdoctoral Fellow
Johns Hopkins Bloomberg School of Public Health