Ethidium bromide (EtBr) is a fluorescent dye widely used in molecular biology research. It is a mutagenic compound that intercalates double-stranded DNA and RNA and has been used in multiple fluorimetric assays for nucleic acids. It is a powerful inhibitor of DNA polymerase. It fluoresces under ultra violet light. Hence, DNA separated using agarose gel electrophoresis can be visualised under UV lamp.