Stereoselective separation and detection of phenoxy acid herbicide enantiomers by cyclodextrin-modified capillary zone electrophoresis–electrospray ionization mass spectrometry

摘要: Abstract An application of on-line coupling capillary electrophoresis and mass spectrometry (CE–MS) to the chiral separation phenoxy acid herbicide enantiomers was investigated. As an ionization method, electrospray (ESI) is used for a CE–MS interface. Generally, nonvolatile additives in solutions sometimes decrease MS sensitivity and/or signal intensity. In this study, however, heptakis(2,3,6-tri- O -methyl)-β-cyclodextrin (TM-β-CD) as selector it migrated directly into ESI By using negative-ionization mode along with methanol–water–formic solution sheath liquid nitrogen gas, stereoselective detection three were successfully achieved 20 m M TM-β-CD 50 ammonium acetate buffer (pH 4.6).