MES sodium salt

MES sodium salt has been used:

• To achieve the required density and stretching of DNA fibers during melting of agarose plugs containing genomic DNA
• To equilibrate the Balch homogenizer chamber and to prevent sample hydrolysis before sample homogenization

MES is one of the so-called "Good" buffers developed for biological applications. This product is tested for trace ions. A buffer using MES free acid can be prepared by titrating the free acid with sodium hydroxide to the desired pH (pKa=±-1). Alternatively, volumes of equimolar solutions of MES free acid and MES sodium can be mixed to attain the desired pH. Standard mixing tables using stock solutions to prepare a buffer of a given pH have been published.

Easily compare specifications for MES sodium salt products with the MES sodium salt specification table.

MES Sodium is soluble in water, giving a clear colourless solution at 25g in 50mL water (approximately 2.3M). The pH of a solution should be between 9 and 10 depending on concentration. Solutions should be stable at 2-8°C for months. Sterilization should be by filteration through 0.2μm filters. Autoclaving is not recommended. If buffers must be nuclease-free, it is best to treat the water first, and then add the buffer solids after autoclaving. When MES solutions are autoclaved, they turn yellow (although pH does not change measurably). The identity of the yellow breakdown product is unknown.