Distribution of Pyridylazophenols and Their Metal Chelates between Two Phases Separated from a Micellar Solution of Octyl-β-D-thioglucoside in the Presence of Polyethylene Glycol

Abstract

Aqueous micellar solutions of octyl-β-D-thioglucoside (OTG) were separated into two phases upon addition of polyethylene glycol 6000 (PEG). In this polymer-induced phase separation, one phase was an aqueous phase in which PEG was retained; the other was a surfactant-rich phase into which pyridylazophenols and their three metal chelates (nickel(II), zinc(II), and cadmium(II)) were extracted. Their distribution constants were highly dependent upon the PEG concentration and the nature of the metal chelate. This observation provides a possibility of controlling the extraction selectivity in polymer-induced phase separation.