Universiti Teknologi Malaysia Institutional Repository

On-line preconcentration and chiral separation of propiconazole by cyclodextrin-modified micellar electrokinetic chromatography

Wan Ibrahim, Wan Aini and Hermawan, Dadan and Sanagi, Mohd Marsin (2007) On-line preconcentration and chiral separation of propiconazole by cyclodextrin-modified micellar electrokinetic chromatography. Journal of Chromatography A, 1170 (1-2). pp. 107-113. ISSN 1873-3778

Full text not available from this repository.

Official URL: http://dx.doi.org/10.1016/j.chroma.2007.09.003

Abstract

A method for the chiral separation of propiconazole using cyclodextrin-modified micellar electrokinetic chromatography (CD-MEKC) with hydroxypropyl-?-cyclodextrin (HP-?-CD) as chiral selector is reported. The use of a mixture of 30 mM HP-?-CD, 50 mM SDS, methanol–acetonitrile 10%:5% (v/v) in 25 mM phosphate buffer solution was able to separate two enantiomeric pairs of propiconazole. Stacking- and sweeping-CD-MEKC under neutral pH (pH 7) and under acidic condition (pH 3.0) were used as two on-line preconcentration methods to increase detection sensitivity of propiconazole. Good repeatabilities in the migration time, peak area and peak height were obtained in terms of relative standard deviation (RSD). A sensitivity enhancement factor of 100-fold was achieved using sweeping-CD-MEKC at acidic pH. This is the first report on the separation of two pairs of propiconazole enantiomers and all the enantiomers of fenbuconazole and tebuconazole using sweeping-CD-MEKC. The limit of detection (S/N = 3) for the three triazole fungicides ranged from 0.09 to 0.1 µg/mL, which is well below the maximum residue limits (MRL) set by Codex Alimentarius Commission (CAC). Combination of solid-phase extraction (SPE) pretreatment and sweeping-CD-MEKC procedure was applied to the determination of selected triazole fungicides in grapes samples spiked at concentration 10–40 times lower than the MRL established by the CAC. The average recoveries of the selected fungicides in spiked grapes samples were good, ranging from 73% to 109% with RSD of 9–12% (n = 3).

Item Type:Article
Uncontrolled Keywords:propiconazole; chiral triazole fungicides; enantiomer separation; capillary electrophoresis; cd-mekc; on-line preconcentration; stacking; sweeping
Subjects:Q Science > QD Chemistry
Divisions:Science
ID Code:8804
Deposited By:INVALID USER
Deposited On:13 May 2009 03:55
Last Modified:13 May 2009 03:55

Repository Staff Only: item control page