Multivariate analysis of elution parameters for RP-HPLC with charged aerosol detection of sucrose caprate regioisomers

BIOCAT2012, Hamburg University of Technology
Book of Abstracts, p290
ISBN 987-3-941492
L73) Multivariate analysis of elution parameters for RP-HPLC with charged aerosol detection of sucrose caprate regioisomers
Aleksander Lie and Lars Haastrup Pedersen
Department of Biotechnology, Chemistry and Environmental Engineering,
Aalborg University, Denmark
Sugar fatty acid monoesters have been shown to possess antibiotic and insecticidal properties. The physical and chemical properties of sugar fatty acid esters depend on the saccharide moiety, fatty acid chain length, and both position and degree of esterification. In the case of sucrose esterification by a single fatty acid potentially results in a total of 255 isomers – eight of which are monoester regioisomers. Enzyme-catalysed regioselective synthesis of sugar fatty acid esters is a very efficient alternative to conventional organic synthesis. Nevertheless, preparative purification is often a necessary downstream processing step to obtain regioisomer pure products. In the present work we have investigated the use of step-down gradient elution profiles to improve regioisomer separation as part of the development of a quantitative HPLC analysis method for sucrose caprate regioisomers. As a sensitive method based on mass detection, charged aerosol detection was used. The investigation was conducted using design-of-experiments (DOE) methodology for development and prediction of elution strategies. The elution profiles were described by a number of important variables, and the resulting data were analysed by multivariate and regression methods. This way four essential variables were identified: 1, initial concentration of acetonitrile; 2, duration of initial concentration; 3, step-down concentration of acetonitrile; and 4, duration of step-down concentration. Eluent time was minimised and baseline separation was achieved for six sucrose caprate regioisomers, while peak resolutions adequate for quantification were achieved for all eight possible regioisomers. The present approach will be used to predict strategies for preparative RP-HPLC.
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