Interface-free two-dimensional heart-cutting capillary electrophoresis is typically used to purify/concentrate and separate a single target fraction. Here, we demonstrate the simultaneous stacking and orthogonal separation of target fractions that belong to two different classes of compounds. The cationic species were first analyzed by capillary zone electrophoresis using an electrolyte of low pH in a fused-silica capillary. The neutrals that remained inside the capillary after the first dimension analysis were then separated by micellar electrokinetic chromatography using sodium dodecyl sulfate micelles that were electrophoretically introduced into the capillary. The suppression of electro-osmotic flow using low pH was essential in shifting the separation selectivity from electrophoresis to electrokinetic chromatography. Two approaches to stacking based on the solubility of the species present were developed. Stacking was achieved during the first dimension analysis via sweeping and/or analyte focusing by micelle collapse. Two artificial mixtures (eight cationic drugs/five neutral steroids, and three quaternary ammonium/three neutral organophosphate pesticides) were successfully analyzed with sensitivity enhancement factors from 15 to 100. Some analytical parameters and application to a spiked real water sample were also studied.

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:	Kukusamude, C (Mr Chunyapuk Kukusamude)
UTAS Author:	Quirino, JP (Associate Professor Lito Quirino)
ID Code:	98468
Year Published:	2014
Web of Science® Times Cited:	25
Deposited By:	Austn Centre for Research in Separation Science
Deposited On:	2015-02-17
Last Modified:	2018-03-14
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