Study of Aqueous Biphasic sSystems Composed of Biocompatible Cholinium Aminoate Ionic Liquids as Novel Extractants and Polyethylene Glycol DiMethyl Ether for Separation of Bovine Serum Albumin (BSA)

Aqueous biphasic systems, ABSs, are known as interesting media for the separation and purification of proteins [1-4]. From this viewpoint, the ambition of this work is investigating ability of cholinium aminoate ([Ch][AA]) as novel, low toxic and high biodegradable ionic liquids including of cholinium glycinate, cholinium prolinate and cholinium valinate for inducing ABSs with polyethylene glycol di-methyl ether, PEGDME, and then evaluating their performances for partitioning of bovine serum albumin, BSA, as a model protein. For achieving this purpose, binodal curves and tie-lines were experimentally measured at 298.15 K for three ABSs. Two empirical equations including Merchuk equation were applied in order to represent the binodal data. Tie-line were correlated with two versions of NRTL models (i.e. e-NRTL and m-NRTL). In addition, the partition behavior of BSA was studied by measuring of partition coefficient and extraction efficiency in mentioned systems.