Products and Services

RSS

BioSepra QMA Spherosil® M, LS ion exchange chromatography sorbents are composed of silica beads grafted with polymer specifically designed for biochemical use. The polymer provides ionic and slightly hydrophobic properties to the sorbent. This unique mix mode chromatography allows the purification of proteins difficult to isolate on classical sorbents. QMA Spherosil M, LS ion exchangers are available in dry form.

Chemical Composition and Structure

QMA Spherosil are rigid beads based on porous silica. The particle size ranges between 100 and 300 µm for LS grade (M grade, with particle size of 40-100 µm is available on request). The silanols covering the pore surface are linked to functionalized polymers (this occurs by covalent binding). The polymer provides the ionic and slightly hydrophobic properties to the sorbent. QMA is a quaternary amine. Silica allows for the combination of high rigidity and high porosity, whereas the role of the cationic polymer is to adsorb the protein to be purified.

Regardless of whether the gel is polyanionic or polycationic, it additionally demonstrates some hydrophobic character. This allows adsorption and elution, but may require the modification of parameters typically selected in hydrophilic ion exchange. The ability to manipulate two physical properties during chromatography makes possible the purification of proteins which have been previously difficult or impossible to isolate on classical gels.