Incorporation of sample stacking techniques into the capillary electrophoresis CF-FAB mass spectrometric analysis of DNA adducts.

Sample stacking is used to improve the detection limits of capillary zone electrophoresis coupled to continuous flow fast atom bombardment mass spectrometry for the analysis of DNA adducts. It was found that, with stacking, the concentration detection limit of deoxynucleotide adducts could be improved by as much as 3 orders of magnitude, thereby bringing it into the 10(-8) M range. In addition, the mass spectrometric mass detection limits of a model acetylaminofluorene deoxyguanosine 5'-monophosphate adduct were found to be in the low picomole range for full scanning and the low femtomole range for multiple reaction monitoring of a selected fragmentation. The techniques have been applied to the analysis of adducts formed in the in vitro reaction of N-acetoxy-N-acetyl-2-aminofluorene with DNA.