Imitation of artificial membrane system via mobile phases with Tween-80 and cholic acid in biopartitioning micellar chromatography.

The chromatographic behaviour of compounds of biomedical significance was studied using micellar mobile phases modified with polyoxyethylene (20) sorbitan monooleate (Tween-80). The influence of the surfactant within the 0.75-4% concentration range on the retention factor of model compounds was investigated. The biological surfactant cholic acid was introduced into the mobile phases in order to approach to the structure of natural membranes, viz. erythrocyte and cytoplasmatic membranes. It was found that curves of dependence of retention factor vs concentration of Tween-80 in the absence and presence of cholic acid in the mobile phase considerably diverge with one another, especially in the 2-3% concentration range of Tween-80 using C18-type support. Increasing the concentration of Tween-80 resulted in the increase of retention factors using phenyl-coated stationary phase.

Influence of nonionic surfactants on the chromatographic behaviour of proteins in hydrophobic interaction chromatography.

The chromatographic characteristics of proteins in the presence of additives of nonionic surfactants Brij-35 and Tween-80 in the conditions of descending gradient of ammonium sulfate and phenyl-coated polymeric stationary phase were investigated. It was revealed that retention factors of proteins may be regulated by use of mentioned additives. The improvement of resolution is achieved for some hardly separated pairs of proteins, viz. albumin egg/albumin bovine, aldolase/tripsin. A reversion of the elution order is observed for tripsin/chymotrypsinogen A.