Many molecules of the phenanthridine group are used as fluorescence tags in gel electrophoresis due to their high quantum efficiencies and stability , , . Ethidium bromide (EtBr) is one of the most used phenanthridine compounds, due to its ability to bind nucleic acids, and has been documented in the literature since 1964 . It is typically seen as the gold standard of the florescence tags used for gel electrophoresis , , . More recently it is being used to assess anti-toxicity studies in bacteria . The ability of EtBr to bind to DNA comes with caution since it has also been shown to stop the nucleic acids synthesis in Strigomonas oncopelti , damage the mitochondrial circular DNA , , and cause mutations in DNA . Despite these negatives, ethidium bromide is still a wellused dye with it ability to bind to different sites on the dsDNA, for which it has a preference, and also to ssDNA structures , . Recently, EtBr is also used as an electrochemical probe molecule . The oxidation of EtBr has been studied using cyclic voltammetry on these, on a variety of working electrode materials such as boron-doped diamond mercury drop systems and large gold electrodes and has been used to electrochemically detect EtBr that is bound to DNA complementing fluorescence approaches .