Related Experiment Video
Updated: Jun 3, 2026

Fast and Sensitive Colloidal Coomassie G-250 Staining for Proteins in Polyacrylamide Gels
Published on: August 3, 2009
Two-dimensional polyacrylamide gel electrophoresis using flat-bed isoelectric focusing in the first dimension
1Jerry Lewis Muscle Research Centre, Royal Postgraduate Medical School, London, UK.
Abstract:
Electrophoretic techniques are, perhaps, the most important group of procedures for the separation and analysis of complex protein mixtures because of their high resolution capacity. This resolving power is maximized in high-resolution, two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) based on the technique developed by O'Farrell (1). This methodology involves a combination of a first-dimension separation in cylindrical isoelectric focusing (IEF) gels containing 9M urea and 2% (w/v) of the detergent NP-40 with discontinuous gradient polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE) in the second dimension. Detailed reviews of the theoretical basis, methodological variations, and applications of this technology can be found in refs. 2-5.
Related Concept Videos
Two-dimensional Gel Electrophoresis
The first dimension separation uses the isoelectric focusing or IEF technique performed on immobilized pH gradient (IPG) strips that separate proteins according to their isoelectric points.
Biological samples, such as cells...
SDS-PAGE
A variation of gel electrophoresis, termed polyacrylamide gel electrophoresis (PAGE), is commonly used for separating proteins according to their molecular size by passing them through a polyacrylamide gel. Because of the varying charges associated with amino acid side chains, PAGE can be used to separate intact proteins...
Electrophoresis: Overview
There...
Capillary Electrophoresis: Applications
Capillary zone electrophoresis (CZE) separates ionic components based on their electrophoretic mobility. It has been used to separate proteins, amino acids,...
DNA Agarose Gel Electrophoresis
Gel extraction follows five major steps: running gel electrophoresis to separate fragments, isolating the individual bands, extracting DNA from those bands, and removing the dye and salts from the extracted mixture to obtain pure DNA.
In cloning experiments, both the insert and vector DNA...

