Publication detail

Towards the Comprehensive Two-Dimensional LCxMEKC Separations using On-Line Preconcentration and Programmed Separation Conditions

Authors: Česla Petr | Fischer Jan | Jandera Pavel

Year: 2011

Type of publication: ostatní - přednáška nebo poster

Page from-to: nestránkováno

Titles:

Language	Name	Abstract	Keywords
eng	Towards the Comprehensive Two-Dimensional LCxMEKC Separations using On-Line Preconcentration and Programmed Separation Conditions	When gradient elution is applied in the first dimension of 2D LCxMEKC system, increasing concentration of organic solvent in the mobile phase and in fractions transferred from LC influences the electroosmotic flow, partitioning equilibria of samples in micelles and properties of the micelles, which results in shifts of migration times during the consecutive runs in the second MEKC separation dimension. The effect becomes more significant with increasing length of the injected sample zone, i.e. during the on-line preconcentration step of transferred LC fraction in the second dimension MEKC separation. In present work, the on-line sweeping preconcentration step with injection of significant part of the volume of transferred fractions from LC was applied in the recently developed LCxMEKC method. The changing composition of micellar pseudostationary phase in background electrolyte was employed to compensate the influence of increasing concentration of acetonitrile on MEKC separation in second dimension.	Two-Dimensional LCxMEKC Separations; On-Line Preconcentration; Programmed Separation Conditions; Micellar Electrokinetic Chromatography

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