Both particle packed (25 cm × 0.46 cm I.D. SUPELCOSIL 5 μm C 18) and monolithic type (10 cm × 0.46 cm I.D. Merck Chromolith Performance C18) reversed-phase substrates were dynamically coated with a carboxybetaine type zwitterionic surfactant ((dodecyldimethyl-amino) acetic acid) and investigated as stationary phases for use in zwitterionic ion chromatography (ZIC). Investigations into eluent concentration and pH were carried out using KCl eluents containing 0.2 mM of the carboxybetaine surfactant to stabilise the column coatings. It was found that eluent concentration decreased anion retention whilst simultaneously increasing peak efficiencies, which may be due to the dissociation of intra- and inter-molecular salts of the carboxybetaine surfactant under higher ionic strength conditions. The Effect of eluent pH was an increase in anion retention with decreased eluent pH due to the increased protonation of the weak acid terminal group of the carboxybetaine, causing both a relative increase in the positive charge of the stationary phase and less repulsion of the anions by the dissociated weak acid group. The carboxybetaine-coated monolithic phase was applied to rapid anion separations using elevated flow rates and flow rate gradients. © 2005 Elsevier B.V. All rights reserved.

Item Type:	Refereed Article
Research Division:	Chemical Sciences
Research Group:	Analytical chemistry
Research Field:	Separation science
Objective Division:	Expanding Knowledge
Objective Group:	Expanding knowledge
Objective Field:	Expanding knowledge in the chemical sciences
UTAS Author:	Nesterenko, PN (Professor Pavel Nesterenko)
UTAS Author:	Paull, B (Professor Brett Paull)
ID Code:	47584
Year Published:	2005
Web of Science® Times Cited:	21
Deposited By:	Chemistry
Deposited On:	2007-09-18
Last Modified:	2011-08-18
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