Co- and Counter-Electroosmotic Flow Capillary Electrophoresis of Anionic Phenols Using UV and MS Detection

Abstract

Co- and counter-electroosmotic flow (EOF) capillary electrophoresis (CE) of anionic phenols, using UV and mass spectrometry (MS) detection were investigated. The co-EOF CE-UV detection was performed by using hexadimethrine bromide (HDB) as an EOF modifier, which provided the separation in 6.2 min. The counter-EOF CE-MS was obtained without HDB and coupling was achieved by sheath liquid interface. The CE-UV provided the better linearity (r ² > 0.99) than the CE-MS (r ² > 0.81), however, both methods gave comparable detection limits (5 µg/mL). CE-UV is efficient for the routine quantitative analysis, whereas CE-MS is useful for identification of the phenols.

Keywords:

• Anionic phenols
• Co-electroosmotic
• Counter-electroosmotic
• MS detection
• UV detection

ACKNOWLEDGMENTS

The authors would like to thank the Alexander von Humboldt Foundation for the support of Leena Suntornsuk (3-THA/118636 STP). Special thanks go to Dr. Markus Martin and Prof. Christian Huber at Saarland University, Instrumental Analysis and Bioanalysis, Saarbruecken, Germany, for kind assistance, valuable discussion, and for providing all facilities.

Manuscript 6453

Notes

^a BEG = 30 mM ammonium acetate buffer (pH 10.0), CE capillary = 88.5 cm (effective length: 80 cm) × 75 µm, 30 kV.

^b for condition 4–7, HDB was added into the BGE, for condition 8–11, HDB was flushed through the capillary during pre-conditioning step.

^c + = positive polarity, − = negative polarity.