Enhanced pH-mediated stacking of anions for CE incorporating a dynamic pH junction.
A technique has been developed to enhance analyte focusing for CE for the analysis of physiological samples. High-ionic-strength samples are titrated to low-ionic-strength on-line using pH-mediated sample stacking in conjunction with a dynamic pH junction. This method concentrates analytes by reducing their electrophoretic mobility during field-amplification. Parameters responsible for enhanced focusing were investigated, and an enhanced pH-mediated stacking method was optimized for anionic nucleosides. The process results in ultra-narrow peak widths, for example, 0.28 s for thymidine with a 10 min analysis time. Peak width and resolution with the enhanced stacking method were also compared to normal base stacking and electrokinetic injection. With this technique, mass-loading capacity can be increased without degradation in peak shape and resolution is dramatically improved.
Arnett
Stacy D
SD
Department of Chemistry, Ralph N. Adams Institute of Bioanalytical Chemistry, University of Kansas, Lawrence, KS, USA.
Lunte
Craig E
CE
D000465:Algorithms; D000838:Anions / Q000032:analysis* / Q000737:chemistry*; D002412:Cations; D019075:Electrophoresis, Capillary / Q000295:instrumentation* / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D007267:Injections; D008956:Models, Chemical; D009994:Osmolar Concentration; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide; D012972:Sodium Hydroxide
D000838:Anions; D002412:Cations; D012972:Sodium Hydroxide; D012822:Silicon Dioxide