AAT Bioquest

Are there safer alternatives to ethidium bromide?

Posted December 2, 2021


Yes, there are safer alternatives to ethidium bromide. Ethidium bromide remains the cheapest and most efficient dye for DNA detection. However, its use is severely restricted because of potential mutagenic, carcinogenic, and teratogenic properties. The alternatives to ethidium bromide are less toxic, but they are more expensive and not as efficient as EtBr.

Safer alternatives to ethidium bromide include:

  • Crystal Violet – Crystal Violet is similar to ethidium bromide in the way that it intercalates with DNA, but it is less mutagenic. In addition, UV exposure is not needed because crystal violet is detectable in the visible range. 100–200 ng bands are detectable.
  • SYBR Safe – SYBR safe is a highly sensitive DNA stain that enables DNA visualization in agarose or acrylamide gels with either blue-light or UV excitation. It is as sensitive as EtBr but with lower mutagenicity. Bands of 1-5 ng can be detected. It can also be used for staining RNA in gels.
  • GelRed – GelRed is a sensitive, robust, and safe DNA stain. It is less mutagenic than ethidium bromide, stable in extreme heat and light, and can be visualized using UV light. GelRed is compatible with all downstream manipulations. Bands of 100–200 ng bands are detectable.
  • Methylene Blue – The major advantage of methylene blue is that it is detectable in the visible range. However, it is not a very sensitive stain. De-staining in water can help increase its sensitivity. Bands of 40-100 ng can be detected.
  • Gelite™ Safe - Gelite™ Safe DNA gel stain is an extremely sensitive and stable fluorescent dye for visualizing DNA in electrophoretic gels. Unlike the highly-toxic ethidium bromide (EtBr), Gelite™ Safe is explicitly designed to be less hazardous, non-cytotoxic, and non-mutagenic, providing greater sensitivity and lower background fluorescence than EtBr and SYBR® Safe.
Additional resources

SYBR safe TM efficiently replaces ethidium bromide in Aspergillus fumigatus gene disruption

Gelite™ Safe DNA Gel Stain, the Best and Most Robust DNA Gel Stain