The 5X Green GoTaq Reaction Buffer contains two dyes (a blue dye and a yellow dye) that separate during electrophoresis to show migration progress. The buffer also contains a compound that increases sample density. This means that samples can be loaded directly onto gels without the need for loading dye. The blue dye migrates at the same rate as a 3-5kb DNA fragment in a 1% agarose gel. The yellow dye migrates at a rate faster than primers (less than50bp) in a 1% agarose gel. The 5X Colorless GoTaq Reaction Buffer has the same formulation as the 5X Green GoTaq Reaction Buffer but does not contain dyes and is recommended for any applications where absorbance or fluorescence measurements are necessary prior to PCR cleanup. Both buffers are supplied at pH 8.5. Cat.# M7911 and M7921 contain MgCl2 at a concentration of 7.5mM, giving a final concentration of 1.5mM in the 1X reaction. Cat.# M8901 and M8911 do not contain magnesium.|