Application of linear solvation energy relationships to polymeric pseudostationary phases in micellar electrokinetic chromatography.

Abstract

Polymerized sodium 11-acrylamidoundecanoate (poly(Na 11-AAU)) was used as a pseudostationary phase (PSP) for micellar electrokinetic chromatography to separate uncharged compounds. The polymer PSP showed signifcantly different solute migration behaviors from conventional micelles including sodium dodecyl sulfate and poly (sodium 10-undecylenate), giving high separation efficiencies (>200000 theoretical plates/m). Linear solvation energy relationships were used to evaluate and characterize the chemical interactions that influence the retention behavior in the poly (Na 11-AAU) micellar system. It was found that the solute volume and solute hydrogen bond basicity mainly influenced the retention. The characteristic feature of the poly (Na 11-AAU) micellar system is that the micelle has a significantly higher capacity for dipole-dipole and dipole-induced dipole interactions as well as a slightly higher capacity for electron pair interactions than the aqueous phase. Due to its unique selectivity, the poly(Na 11-AAU) micellar system would become an attractive new option for selectivity optimization on methods development.