fast-atom bombardment mass spectrometry has been used to obtain spectra of conjugated benzo ( a ) pyrene ( bap ) metabolites using a 1:1 , glycerol + thioglycerol matrix , bap glucuronides give positive- and negative-ion spectra with peaks due to [ m + h ] + and [ m - h ] - ions and a major fragment peak ( base peak ) at [ bap-oh ] + and [ bap-o ] - .
C0017861
glycerol
C0076470
matrix