Influence of pre-electrophoresis on protein separations in polyacrylamide gels

Polyacrylamide gel electrophoresis (PAGE) is a widely used technique in protein separations. In this study, the effects of pre-electrophoresis (i.e., exposing polyacrylamide gels to an electrical field prior to loading samples) on the separation of a mixture of 10 standard proteins was investigated. Three different gel concentrations (based on amounts of acrylamide and bis-acrylamide, always at a 37.5:1 ratio) relative to the volume of the gel solution were tested: 6%, 9%, and 12%. For each concentration, multiple slab gels were subjected to pre-electrophoresis prior to separation of proteins, while multiple other (i.e., companion) slab gels were used but without applying the pre-electrophoresis technique. Separation results were investigated, showing that the application of the pre-electrophoresis technique had a significant effect on separations particularly for 6% and 9% gels.