CHARGE-REMOTE FRAGMENTATION OF SULFATED AND GLUCURONIDATED BILE-ACIDS AND THEIR 2-AMINOETHANESULPHONIC ACID-DERIVATIVES

Negative-ion fast-atom bombardment mass spectra of bile acids show prominent [M-H]- pseudomolecular ions, and few fragment ions. Collision-induced dissociation of such pseudomolecular ions gives charge-remote fragmentations which are useful in structural identifications. It has been shown that bile acids conjugated with taurine (2-aminoethanesulphonic acid) give more intense and informative collision-induced dissociation spectra than unconjugated bile acids. In this laboratory, a procedure for the aminosulphation of biological samples, for analysis by tandem mass spectrometry, has been developed. In the present study, a comparison has been made between the collision-induced dissociation spectra of a series of sulphated and glucuronidated bile acids and their 2-aminoethanesulphonic acid derivatives.