title: Unusual peaks and baseline shifts in capillary electrophoresis.
abstract: Emersion peaks, baseline shifts, and spontaneous-marker peaks in CE are documented. These baseline perturbations are observed in a simple CE system that does not employ sample injection and with sodium benzoate as the running electrolyte. Emersion peaks are attributed to the preferential adsorption of electrolyte at the air-solution interface formed upon emersion of the capillary inlet. Baseline shifts are believed to be caused by field-dependent changes in electrolyte concentration entering the capillary. These shifts may be accompanied by spontaneous-marker peaks, which may be caused by diffusion into or out of the capillary inlet between electrophoretic experiments. All baseline perturbations are detected as a change in UV absorbance signal and are transported by electroosmotic flow.
authors.affiliation: Department of Chemistry, University of Alberta, Edmonton, Canada.
authors.forename: C L
authors.initials: CL
authors.lastname: Colyer
mesh_terms: D000327:Adsorption; D001565:Benzoates; D019817:Benzoic Acid; D002138:Calibration; D002197:Capillary Action; D004573:Electrolytes; D019075:Electrophoresis, Capillary / Q000295:instrumentation* / Q000379:methods*; D015203:Reproducibility of Results
chemical_list: D001565:Benzoates; D004573:Electrolytes; D019817:Benzoic Acid