Surfactant-mediated capillary electrochromatography with octadecyl-silica- packed capillary columns for the separation of nonpolar compounds. Case of pyrethroid insecticides.
Capillary electrochromatography (CEC) with octadecyl-silica-packed capillary columns was evaluated in the separation of nonpolar compounds, e.g., pyrethroid insecticides, using surfactant-rich mobile phases. This novel concept is referred to as surfactant-mediated capillary electrochromatography (SM-CEC), and is based on including a charged surfactant, namely sodium di-2-ethylhexyl sulfosuccinate (DOSS), in the mobile phase. Under these conditions, DOSS plays the role of a slowly moving pseudostationary phase so that solutes are partitioned between a mobile phase, a fixed stationary phase and a slowly moving pseudostationary phase. The SM-CEC system was investigated with pyrethroid insecticides over a wide range of DOSS and acetonitrile concentrations in the mobile phase. Pyrethroid insecticides, which are very hydrophobic solutes consisting of geometric isomers and diastereomers, were better resolved in SM-CEC than in straight CEC.
Tegeler
Tony
T
Department of Chemistry, Oklahoma State University, Stillwater, OK 74078-3071, USA.
El-Rassi
Ziad
Z
D000097:Acetonitriles / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods / Q000592:standards; D004143:Dioctyl Sulfosuccinic Acid / Q000737:chemistry; D019075:Electrophoresis, Capillary / Q000379:methods* / Q000592:standards; D057927:Hydrophobic and Hydrophilic Interactions; D007202:Indicators and Reagents / Q000737:chemistry; D007306:Insecticides / Q000302:isolation & purification*; D011722:Pyrethrins / Q000302:isolation & purification*; D012822:Silicon Dioxide; D013501:Surface-Active Agents / Q000737:chemistry
D000097:Acetonitriles; D007202:Indicators and Reagents; D007306:Insecticides; D011722:Pyrethrins; D013501:Surface-Active Agents; C026679:octadecylsilica; D004143:Dioctyl Sulfosuccinic Acid; D012822:Silicon Dioxide