Enantiomeric separations by capillary electrophoresis: Theoretical method to determine optimum chiral selector concentration

A method to optimize the ligand concentration [S] in the background electrolyte of capillary electrophoresis separations is presented. It is based on the use of a model which predicts apparent electrophoretic mobilities as a function of ligand concentration (expressed as p[S] = −log[S]). This model...

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Detalhes bibliográficos
Autores: Lancioni, Carlina, Keunchkarian, Sonia, Castells, Cecilia Beatriz Marta, Gagliardi, Leonardo Gabriel
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2018
País:Argentina
Recursos:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositório:CONICET Digital (CONICET)
Idioma:inglês
OAI Identifier:oai:ri.conicet.gov.ar:11336/99696
Acesso em linha:http://hdl.handle.net/11336/99696
Access Level:Acceso aberto
Palavra-chave:CAPILLARY ELECTROPHORESIS
CHIRAL SEPARATION
CYCLODEXTRIN
MULTICRITERION OPTIMIZATION FUNCTION
SEPARATION OPTIMIZATION
https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
Descrição
Resumo:A method to optimize the ligand concentration [S] in the background electrolyte of capillary electrophoresis separations is presented. It is based on the use of a model which predicts apparent electrophoretic mobilities as a function of ligand concentration (expressed as p[S] = −log[S]). This model is employed to compose the expression of a recently proposed criterion to qualify separations in electrophoresis. Two strategies to find the optimum p[S], leading to the best separation of all compounds, are explained: 1.- a graphical method using a windows map depicting the single separation criteria between all possible combination of compounds by pairs, and 2.- an analytical method where an extended multicriterion optimization function is composed and optimum p[S] is found by mathematical maximization. The procedure is applied to a hard-to-separate model system: enantiomeric separations of racemic mixtures. 2-Hydroxypropyl-β-cyclodextrin was chosen as a model ligand, and four pharmaceutical drugs as model analytes. In order to demonstrate the performance of the procedure, results of electrophoretic separations obtained at p[S] found as optimum are compared with separations obtained at p[S] values slightly higher and lower than the optimum.