【摘 要】
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The great demand for enantiopure substances imposed the development of appropriate and accurate analytical techniques and methods.Enantioselective separations are widely connected to gas chromatograph
【机 构】
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Dipartimento Farmaco-chimico, Facoltà di Farmacia, Università di Messina, viale Annunziata, 98168-Me
【出 处】
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DaLian Internationall Symposia and Exhibition on Chromatogra
论文部分内容阅读
The great demand for enantiopure substances imposed the development of appropriate and accurate analytical techniques and methods.Enantioselective separations are widely connected to gas chromatography (GC), and its hyphenation to mass spectrometry (MS) presents to be of advantage for qualitative information.However, in GC-Enantio/MS, since stereoisomers are compounds made up of the identical atoms connected by the same sequence of bonds, but having different three dimensional structures, it is expected that pairs of enantiomers present a similar fragmentation pattern.This similarity can limit the identification of a target compound specially when the unknown spectra matching is made solely by its comparison to reference compounds MS spectra.Moreover, a reliable peak assignment of enantiomers is hindered not only by the MS spectra similarity, but also by not surely established elution orders.To support MS data, linear retention index (LRI) values based on different homologous series (n-alkanes, FAMEs and FAEEs) can be determined for the resolved enantiomers in different chiral stationary phases (CSP).However, considering closely eluting enantiomers, with retention indices separated by few index units, the LRI looses reliability.
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