Electrospray time-of-flight mass spectrometry was employed to investigate chiral molecular recognition of pseudoephedrine using α- cyclodextrin, β-cyclodextrin and γ-cyclodextrin as chiral selectors. The effect of nozzle potential on chiral recognition of cyclodextrins was also studied.Strong chiral recognition ability of these three cyclodextrins was revealed by the mass spectra based on the protonated complexes of pseudoephedrine with cyclodextrins. It was demonstrated that three chiral selectors possess their individual chiral recognition characteristics when nozzle potential changed.

Key words: CYCLODEXTRIN, TIME-OFF FLIGHT MASS SPECTROMETRY, molecular recognition