Thermo Fisher, R0611, DNA Gel Loading Dye (6X)

Thermo Scientific DNA Gel Loading Dye (6X) prepares nucleic-acid samples and size markers for conventional agarose and polyacrylamide gel electrophoresis. Bromophenol blue and xylene cyanol FF provide two visible migration fronts for monitoring separation without adding fluorescent signal to the sample. Glycerol increases sample density so the liquid settles into the loading well, while EDTA chelates divalent cations that support metal-dependent nuclease activity. Each package contains five 1 mL aliquots of sixfold-concentrated dye. For a final concentration of 1X, add one volume of dye to five volumes of DNA sample; mix before carefully loading the gel. On a 1% agarose gel, bromophenol blue typically migrates near 300 bp and xylene cyanol FF near 4 kb, although migration varies with gel composition and running conditions. The dye assists with sample loading and tracking; it is not itself a nucleic-acid stain.