Investigation of the retention mechanism in nonionic micellar liquid chromatography using an alkylbenzene homologous series

Journal Article · Tue Nov 15 04:00:00 EST 1988 · Anal. Chem.; (United States)

DOI:https://doi.org/10.1021/ac00173a018· OSTI ID:6357568

Borgerding, M F; Quina, F H; Hinze, W L; Bowermaster, J; McNair, H M

Micellar liquid chromatography (MLC) of a homologous series of alkylbenzenes with two nonionic micellar mobile phases, i.e., poly(oxyethylene(10 or 23))dodecanol (Brij-22 or Brij-35), indicates a linear relationship between the capacity factor, k', and the homologue carbon number, n/sub c/. This is in contrast to the usual log k' vs n/sub c/ relationship found for a conventional methanol-water mobile phase. In order to identify the origin of this difference, the various partition coefficients unique to MLC were determined as a function of carbon homologue number in the usual manner, employing an improved procedure for estimation of the chromatographic phase ratio based on measurement of the cumulative pore volumes of the stationary phase. Examination of the partition coefficient data, together with solute selectivity and water solubility data, leads to the conclusion that separate and distinct retention mechanisms are operative in MLC, depending upon the degree of water solubility or insolubility of the solute. Thus, the retention of sparingly soluble or water-insoluble solutes is largely governed by the partition coefficient associated with the direct transfer of the solute from the mobile phase micelle to the surfactant-modified (hemimicellar) stationary phase. A solubility limit equation, derived from the original Armstrong-Nome MLC theory, is shown to describe the observed linear k' vs n/sub c/ behavior adequately for the homologous series with these micellar mobile phases.

• Research Organization: Wake Forest Univ., Winston-Salem, NC (USA)
• OSTI ID: 6357568
• Journal Information: Anal. Chem.; (United States), Journal Name: Anal. Chem.; (United States) Vol. 60:22; ISSN ANCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400105* -- Separation Procedures
ALKANES
AROMATICS
CHROMATOGRAPHY
DATA
EQUATIONS
EXPERIMENTAL DATA
FUNCTIONS
HYDROCARBONS
INFORMATION
LIQUID COLUMN CHROMATOGRAPHY
MICELLAR SYSTEMS
NUMERICAL DATA
ORGANIC COMPOUNDS
PARTITION FUNCTIONS
PHASE STUDIES
PREDICTION EQUATIONS
SEPARATION PROCESSES
SOLUBILITY
TIME DEPENDENCE