Premium
Microemulsion electrokinetic chromatography of drugs varying in charge and hydrophobicity: I. Impact of parameters on separation performance evaluated by multiple linear regression models
Author(s) -
Harang Valérie,
Eriksson Jessica,
Sängervan de Griend Cari E.,
Jacobsson Sven P.,
Westerlund Douglas
Publication year - 2004
Publication title -
electrophoresis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.666
H-Index - 158
eISSN - 1522-2683
pISSN - 0173-0835
DOI - 10.1002/elps.200305671
Subject(s) - microemulsion , electrokinetic phenomena , chemistry , pulmonary surfactant , chromatography , sodium dodecyl sulfate , micellar electrokinetic chromatography , analytical chemistry (journal) , propanol , octane , selectivity , cationic polymerization , toluene , diffusion , capillary electrophoresis , ethanol , organic chemistry , thermodynamics , biochemistry , catalysis , physics
The separation of anionic, cationic and neutral drugs in microemulsion electrokinetic chromatography (MEEKC) was studied with a statistical experimental design. The concentration of sodium dodecyl sulfate (SDS, surfactant), 1‐butanol (co‐surfactant) and borate buffer and the factors Brij 35 (surfactant), 2‐propanol (organic solvent) and cassette temperature were varied simultaneously, while the parameters pH (9.2), the concentration of octane (oil, 0.8% w/w), the voltage (10 kV) and the dimension of the fused‐silica capillary, were kept constant. Eight different model substances were chosen with different hydrophobicities. Two of the analytes were positively charged, two were negatively charged, and the remaining four were neutral or close to neutral at the pH explored. The importance of each parameter on the separation window, the plate height and the retention factor for each of the analytes was studied by means of multiple linear regression (MLR) models. A new response was evaluated for anions, the quotient between the effective mobility in the microemulsion and the effective mobility in the corresponding buffer. Factors affecting selectivity changes were also explored, and it was found that SDS and 2‐propanol had the largest effect on selectivity.