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
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Official URL: http://dx.doi.org/10.1016/j.chroma.2007.09.003
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, methanolâ€“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 Âµg/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 10â€“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 9â€“12% (n = 3).
|Uncontrolled Keywords:||propiconazole; chiral triazole fungicides; enantiomer separation; capillary electrophoresis; cd-mekc; on-line preconcentration; stacking; sweeping|
|Subjects:||Q Science > QD Chemistry|
|Deposited By:||INVALID USER|
|Deposited On:||13 May 2009 03:55|
|Last Modified:||13 May 2009 03:55|
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