EFFECT OF ORGANIC MODIFIERS ON THE CAPACITY FACTOR IN MICELLAR ELECTROKINETIC CHROMATOGRAPHY

Organic modifiers were effective both to extend the migration time win dow and to improve the separation of very hydrophobic compounds in MEK C. An iteration method was used to determine the migration time of mic elles. The quantitative relationship between the capacity factor k' an d the concentration of organic modifiers was derived, which was invest igated experimentally. The linear solvation energy relationships (LSER ) methodology was applied to MEKC, and good linear relationships betwe en lnk' and solvatochromic parameters of 15 solutes were obtained in t he presence of organic modifier in different concentrations, which ind icated a new access in MEKC to predict k' from the structural paramete rs of solutes. The effect of column temperature T on k' was also inves tigated.