Charge‐remote fragmentation of bile acids derivatized with amino‐sulphonic acids

Abstract

Abstract Negative‐ion fast‐atom bombardment mass spectra of free and conjugated bile acids are dominated by [M  H]− pseudomolecularions. Collision‐induced dissociations of these pseudomolecular ions give charge‐remote fragmentation patterns which are useful for structural identification. Taurine (2‐aminoethanesulrtionic acid)‐conjugated bile acids have a high cross‐section for charge‐remote fragmentation, and give the most informative and intense spectra among the naturally occurring bile acids. In the present study, collision‐induced dissociation spectra of bile acids derivatized with different aliphatic and aromatic aminosulphonates, and with 2‐amlnoethyl hydrogen sulphate have been compared. All show charge‐remote fragmentation patterns. Determination of the intensities of the fragment ions shows that the highest sensitivity is usually obtained with aromatic aininosulpho‐nate derivatives.