4-Morpholineethanesulfonic acid, sodium salt (MES) is a popular zwitterionic buffer in scientific research due to its excellent properties. It can buffer solutions effectively within a pH range of 5.5-6.5 with a pKa value of 6.1. This product is BioPerformance certified and it finds extensive application as a buffering agent in biochemistry and molecular biology experiments, contributing to the stabilization of pH in different biological reactions including western blotting, cell culture and electrophoresis.
MES is one of the so-called 'Good' buffers developed for biological applications. 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.
Application:
MES sodium salt has been employed as a coupling buffer for amine-reactive sensors at either pH 4.5 or pH 5.0 to facilitate the coupling of monoclonal antibodies (MAbs) onto the sensors, used in hybridization studies with fluorescently-labeled complementary strands and microarray slide washing during microarray analysis, and played a role in preparing a new set of RNA phosphoramidites compatible with in situ photolithography for growing RNA oligonucleotides on microarrays.
MES sodium salt has been used as a coupling buffer during the coupling of MAbs onto amine-reactive sensors. It has also been used as a component of germination medium and shoot induction medium during in vitro plant regeneration.