Comparative analysis of the DNA staining efficiencies of different fluorescent dyes in preparative agarose gel electrophoresis.

Ethidium bromide (EB) is a mutagen and toxin that is widely used in the laboratory for visualization of nucleic acids. Safer nucleic acid stains, such as SYBR Gold, SYBR Green, GoldView, GeneFinder, and GoldStar, have been developed. However, there has been no systematic comparative analysis of the staining efficiencies of these dyes. In the present study, SYBR Gold, SYBR Green I, GoldView and EB were compared. Although both SYBR Gold and SYBR Green alter electrophoretic mobility and thus DNA size estimates, they are cost-effective alternatives to EB. SYBR Gold was more sensitive than SYBR Green I at detecting short fragments, but 50-bp bands were clearly visible using either dye when visualized with a long integration time. SYBR Gold or SYBR Green I are sensitive and relatively safe alternatives to EB. In our laboratory, the SYBR Gold method is now used routinely by all members of our group with great consistency and success.