Q.In which technique is Ethidium Bromide used ?

Ethidium bromide is the intercalating dye used to stain and visualise DNA bands in agarose gel electrophoresis.

Working

In Agarose Gel Electrophoresis, DNA fragments (negatively charged, due to their phosphate backbone) are loaded into wells cut in an agarose gel, and an electric current is applied so that the fragments migrate through the gel matrix, with smaller fragments moving faster and travelling further than larger ones, achieving size-based separation. Because DNA itself is colourless, the gel is stained with Ethidium bromide, a planar dye molecule that inserts (intercalates) between the stacked base pairs of the double helix. When exposed to UV light, ethidium-bromide-bound DNA fluoresces bright orange, allowing the separated DNA bands to be seen and photographed directly on the gel. Ethidium bromide is not a reagent of the Polymerase Chai …