Gel shift assays or electrophoretic mobility shift assays (EMSA) provide a simple method to study DNA-protein interactions. This assay is based on the principle that DNA-protein complexes will have a different mobility during electrophoresis than non-bound DNA. These shifts can be visualized on a native acrylamide gel using labeled DNA to form the DNA-protein binding complex.

To date, protocols require labeling DNA by radioisotope, digoxygenin, or biotin. The Odyssey® Infrared EMSA Kit coupled with IRDye® 700 EMSA oligonucleotides is an excellent alternative method to radioisotopic and chemiluminescent detection methods for EMSA analysis and visualization. Using IRDye EMSA reagents, assays can be completed in less than two hours with no gel transfer or film exposure. The gel doesn’t even have to be removed from the glass plates for imaging.