2-D Gel Electrophoresis (2DGE)

Two-dimensional (2-D) gel electrophoresis is a powerful, widely used method for high-resolution analysis of complex protein mixtures from cells and other biological samples. The technique is a core component in the proteomics lab, due to its ability to separate and resolve thousands of proteins in a single gel. Proteins are separated in two steps: isoelectric focusing (according to isoelectric point) and SDS-PAGE (by molecular weight). 2-D electrophoresis applications include protein expression analysis, post-translational modification studies, and biomarker analysis. Complete 2-D electrophoresis systems are available, such as the Multiphor II, or can be assembled from modular components. The first dimension can be run in tube gels or fixed gradient gel strips (IPG strips). The second dimension can be run in a vertical or horizontal gel box depending on gel size and electrophoresis conditions. Sample preparation and cleanup with accessories such as sample homogenizer and clean up kits, is an integral part of the 2-D process. Important considerations for 2-D are sample size, pH range and purity, desired resolution, reproducibility and the ability to run multiple gels simultaneously.