Differentiation of enantiomers using matrix‐assisted laser desorption/ionization mass spectrometry

Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has successfully been used to differentiate pseudo-enantiomeric (isotopically labelled) amino acids by using cyclodextrin as complexing host. By using different pseudo-enantiomeric mixtures (i.e. RDn + S; and R + SDn), it has been demonstrated that the preference of cyclodextrin for S-enantiomers is not due to the size differences caused by the hydrogen/deuterium substitution. It is postulated that this method can be extended to differentiate enantiomers (and determine enantiomeric excess) by using a pair of enantiomeric hosts, as demonstrated previously using other ionization techniques, but with much higher sensitivity. Copyright © 2000 John Wiley & Sons, Ltd.