Influence of the unpacked section on the chromatographic performance of duplex strong anion-exchange columns in capillary electrochromatography

Byrne, Christopher D.; Smith, Norman W.; Dearie, H S; Moffatt, Frank; Wren, Stephen; Evans, Kenneth P.

doi:10.1016/s0021-9673(01)01061-5

Cited by 11 publications

(5 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Column Fabrication for CEC-MS and Retention Time Reproducibility Study. For most of the current CEC column configurations, − the packed column consists of two segments. A packed segment is usually followed by an open tubular segment to achieve on-column UV detection.…”

Section: Resultsmentioning

confidence: 99%

Combination of Chiral Capillary Electrochromatography with Electrospray Ionization Mass Spectrometry: Method Development and Assay of Warfarin Enantiomers in Human Plasma

Zheng

Shamsi

2003

Anal. Chem.

View full text Add to dashboard Cite

The hyphenation of chiral capillary electrochromatography (CEC) with electrospray ionization mass spectrometry (ESI-MS) is very challenging but promising due to the fact that it combines sensitivity with high specificity and selectivity. In this work, CEC capillaries packed with (3R,4S)-Whelk-O1 chiral stationary phase were used for simultaneous enantioseparation of (+/-)-warfarin and its internal standard, (+/-)-coumachlor. Furthermore, both the chiral CEC separation and MS detection parameters were examined in detail. First, the influence of different column fabrication was investigated. Second, enantioseparation was optimized by varying CEC parameters, including acetonitrile concentration, buffer pH, and ionic strength. Under the optimum chiral CEC conditions, ESI-MS parameters such as sheath liquid pH and composition, sheath liquid flow rate, drying gas flow rate, drying gas temperature, nebulizer pressure, and fragmentor voltage were investigated to achieve maximum MS signals of the separated enantiomers. Finally, using solid-phase extraction as sample preparation method, (+/-)-warfarin spiked in 100-microL human plasma samples were analyzed. The calibration curves showed good linearity for both (R)-warfarin (R = 0.9979) and (S)-warfarin (R = 0.9978) enantiomers. The experimental limit of detection was approximately 25 ng/mL for both enantiomers. Even though the data are still preliminary, we can state with confidence that chiral CEC-ESI-MS has the potential to establish itself as a very powerful technique for the determination of enantiomeric ratios in human body fluid.

show abstract

Section: Resultsmentioning

confidence: 99%

Combination of Chiral Capillary Electrochromatography with Electrospray Ionization Mass Spectrometry: Method Development and Assay of Warfarin Enantiomers in Human Plasma

Zheng

Shamsi

2003

Anal. Chem.

View full text Add to dashboard Cite

show abstract

“…Byrne et al [323] undertook a detailed study of the contribution of the capillary wall and stationary phase to the EOF using a Spherisorb SAX stationary phase. The columns under study were either fully or partially (viz.…”

Section: Anion Exchangers (Ax)mentioning

confidence: 99%

Stationary and mobile phases in capillary electrochromatography (CEC)

Jiskra

Claessens²,

Cramers

2003

J of Separation Science

View full text Add to dashboard Cite

Stationary and mobile phases in capillary electrochromatography (CEC)This review describes the state of the art of capillary electrochromatography (CEC). Properties of and interactions between stationary and mobile phases applied in CEC are described and discussed; developments in stationary phases, partly also monolithic stationary phases, are reviewed. Special attention is paid to the comparison of the behaviour of stationary and/or mobile phases under CEC versus HPLC conditions with respect to variables such as particle and pore size of the stationary phase, mobile phase composition, and temperature. These issues are discussed throughout the paper. A number of applications in CEC is presented as well.

show abstract

“…As for columns packed with particles that are currently available, we obtain higher performance with an open capillary. In addition, the simplicity of the Byrne et al [37] have recently published a study where it is seen that having a segmented column can sometimes have a deleterious effect on separation. Here, normal fused-silica capillaries are packed with strong ion-exchange particles, resulting in formation of counter-directional EOF in the two segments and causing a massive degradation in column performance.…”

Section: Case Of Segmented Cec Columnsmentioning

confidence: 99%

“…Using pore size distribution data by mercury intrusion porosimetry, fractions of total column void volume contributed by pores were determined. The effective particle diameter, d p,eff , for a given type of packing was found to be dependent upon the pore size distribution of the material, its porosity, and the ionic strength of the eluent and was expressed as d p,eff = 3.57d ch (37) where the average channel diameter d ch was obtained as a weighted average of the individual flow channels. This model also treated intraparticle and interstitial channels as parallel cylindrical capillary tubes.…”

Section: Parallel Tube Model For Packed Bedsmentioning

confidence: 99%

Theory of electroosmotic flow, retention and separation efficiency in capillary electrochromatography

Rathore¹

2002

Electrophoresis

View full text Add to dashboard Cite

This article reviews recent progress that has taken place in the past decade (1992-2002) in the areas of understanding of flow of ions, buffers, as well as neutral and charged sample components through open channels and porous media. Though, primarily dealing with open capillaries and packed columns that are often used in capillary electrochromatography (CEC), these fundamental concepts are applicable to the evolving area of separations on a microchip.

show abstract

Influence of the unpacked section on the chromatographic performance of duplex strong anion-exchange columns in capillary electrochromatography

Cited by 11 publications

References 36 publications

Combination of Chiral Capillary Electrochromatography with Electrospray Ionization Mass Spectrometry: Method Development and Assay of Warfarin Enantiomers in Human Plasma

Combination of Chiral Capillary Electrochromatography with Electrospray Ionization Mass Spectrometry: Method Development and Assay of Warfarin Enantiomers in Human Plasma

Stationary and mobile phases in capillary electrochromatography (CEC)

Theory of electroosmotic flow, retention and separation efficiency in capillary electrochromatography

Contact Info

Product

Resources

About