Chiral separation of aryloxyphenoxy-propionate herbicides in a permethyl-β-cyclodextrin based column. Influence of temperature and mobile phase composition on enantioselectivity.

Autor: Lubomirsky E; Laboratorio de Investigación y Desarrollo de Métodos Analíticos (LIDMA) and División Química Analítica, Facultad de Ciencias Exactas, UNLP, La Plata, Argentina., Padró JM; Laboratorio de Investigación y Desarrollo de Métodos Analíticos (LIDMA) and División Química Analítica, Facultad de Ciencias Exactas, UNLP, La Plata, Argentina., Di Loreto H; Agrofina S. A, Laboratorio de Desarrollo Analítico, Ciudad Autónoma de Buenos Aires, Argentina., Castells CB; Laboratorio de Investigación y Desarrollo de Métodos Analíticos (LIDMA) and División Química Analítica, Facultad de Ciencias Exactas, UNLP, La Plata, Argentina.
Jazyk: angličtina
Zdroj: Electrophoresis [Electrophoresis] 2017 Aug; Vol. 38 (15), pp. 1948-1955. Date of Electronic Publication: 2017 May 11.
DOI: 10.1002/elps.201600528
Abstrakt: We used a permethyl-β-cyclodextrin chiral stationary phase under reversed-phase conditions for the chiral separation of four aryloxyphenoxy-propionate herbicides (fenoxaprop-p-ethyl, quizalofop-p-ethyl and tefuryl, and haloxyfop-p-methyl) with mixtures of methanol, ethanol, 2-propanol, n-propanol, tert-butanol, or acetonitrile and water as mobile phases and investigated the influence of mobile phase composition and column temperature (from 0 to 50°C) on the separation. The retention factors (k) and selectivity factors (α) of all the herbicides investigated decreased with increasing temperature. The lnα versus 1/T and lnk versus 1/T plots for the enantiomers of the chiral pesticides were linear within the range of 0-50°C with all alcohol/water mixtures constituting the mobile phase, but the lnk versus 1/T plots were nonlinear for all the enantiomers chromatographed in acetonitrile/water mixtures. The thermodynamic parameters based on linear van't Hoff plots were calculated. The influence of temperature and mobile phase composition on the enantioseparation of the solutes has rarely been considered simultaneously. The temperature and the solvents used in the mobile phase, however, were found to have a profound effect on the enantioseparation of these herbicides.
(© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
Databáze: MEDLINE
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