Open Access Repository
Mixed-mode capillary electrochromatographic separation of anionic analytes
Downloads
Downloads per month over past year
![]() |
PDF
202.pdf.pdf | Request a copy Full text restricted Available under University of Tasmania Standard License. |
Abstract
In this work, mixed-mode capillary electrochromatography is introduced as a method for selectivity manipulation in the separation of charged analytes and is investigated for a number of analytes. This concept involves utilising a component of the eluent to permit the chromatographic and capillary electrophoresis (CE) separation mechanisms to contribute in varying proportions to the separation. This approach was first investigated using a combination of CE with reversed-phase liquid chromatography (RP-LC) for hydrophobic, charged analytes (aliphatic sulfonates), and using the concentration of organic modifier in the eluent to control the contributions of CE and RP-LC. However, the use of reversed-phase columns was found to be problematic for mobile phases with less then 50% organic modifier due to the hydrophobicity of the stationary phase causing the column bed to overheat and dry, and low electroosmotic flow (EOF) values (µ ? 17.8 × 10–9 m2 V–1 s–1) caused additional restrictions. In a second case, ion-exchange stationary phases were used, with the type and concentration of a competing anion in the eluent being used to control the contributions of ion chromatography (IC) and CE to the separation. Nine common inorganic anions were separated using a silica based anion-exchange column and phosphate (pH 7.20) or sulfate (pH 8.2) as eluent with direct UV detection at 214 nm and 17 inorganic and small organic anions were separated using a nitrate eluent (pH 6.80) with indirect UV detection at 214 nm. The separation selectivity was shown to be a combination of IC and CE.
Item Type: | Article |
---|---|
Authors/Creators: | Hilder, EF and Macka, M and Haddad, PR |
Keywords: | mixed-mode capillary electrochromatography,charged analytes, chromatographic and capillary electrophoresis (CE) separation mechanisms, reversed-phase liquid chromatography, hydrophobic, charged analytes, ion-exchange stationary phases, |
Journal or Publication Title: | Analytical Communications |
ISSN: | 1359-7337 |
DOI / ID Number: | 10.1039/a904506f |
Additional Information: | © Royal Society of Chemistry 1999. |
Item Statistics: | View statistics for this item |
Actions (login required)
![]() |
Item Control Page |