title: Improved sensitivity in detection of chlormequat by liquid chromatography-mass spectrometry.
abstract: Two published separations, using electrospray mass spectrometry (ES-MS), exhibit significant differences in limits of detection (LODs) for chlormequat cation in pear. Separation on ODS1, confirmed to result from ion-exchange, gives shorter analysis times and calibration over a wider concentration range than on an SCX cation-exchange column. The superior LOD using ODS1 (0.04 ng ml(-1) vs. 1.0 ng ml(-1)) results mainly from better chromatographic peak shape. Separation on ODS1 combined with optimised ES-MS detection allows direct quantification of chlormequat on an ion trap instrument at levels lower than those required for residue analysis in foods and also in drinking water.
authors: Chemistry Department, University of York, Heslington, UK.
authors: C S
authors: CS
authors: Evans
authors: J R
authors: JR
authors: Startin
authors: D M
authors: DM
authors: Goodall
authors: B J
authors: BJ
authors: Keely
mesh_terms: D002716:Chlormequat / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002852:Chromatography, Ion Exchange / Q000379:methods*; D012680:Sensitivity and Specificity
chemical_list: D002716:Chlormequat