Supported molecular matrix electrophoresis

Abstract

Supported molecular matrix electrophoresis (SMME) is an electrophoresis using the polyvinylidene difluoride (PVDF) filter membrane which is normally used for Western blotting. SMME membrane is not just a PVDF filter membrane. It requires hydrophilic polymer as an essential component. In SMME, a hydrophilic polymer such as polyvinyl alcohol (PVA) serves as a separation medium within a porous PVDF membrane filter. The PVDF membrane is enough inert to harsh chemical conditions including reductive ß-elimination for releasing of O-linked glycans. This property broadens applications of post-electrophoresis analysis such as glycan analysis and staining methods. Moderate hydrophobicity derived from the PVDF membrane is essential to immobilization of glycoproteins through hydrophobic adsorption with the membrane. Proteins separated by this method can be immunoblotted without any transferring procedures. Mucins can be barely characterized by proteomics technique such as 2D gel electrophoresis because of an inability to enter a gel of SDS-PAGE and their protease resistance. SMME is rapid and simple compared with the proteomic techniques and can be used for analysis of mucins. Glycan analysis and immunostaining of the separated mucins on the SMME membrane are possible. This method can be applied to other types of proteins including serum proteins.