THERMOSPRAY LIQUID-CHROMATOGRAPHY MASS-SPECTROMETRY OF THE DNA-ADDUCTS FORMED BETWEEN 2'-DEOXYNUCLEOSIDES AND BISPHENOL-A-DIGLYCIDYL ETHER

The adducts formed between 2'-deoxyadenosine (dAdo), 2'-deoxycytidine (dCyd), 2'-deoxyuridine (dUrd), 2'deoxyguanosine (dGuo) and bisphenol A diglycidyl ether (BPADGE) were analysed by high-performance liquid c hromatography (HPLC) and thermospray liquid chromatography-mass spectr ometry. An HPLC method was developed using a 5RP8 select B column (125 x 4 mm i.d.) and a mobile phase of MeOH/0.1 M NH4OAc at a flow-rate o f 0.8 ml min(-1), A sample enrichment procedure using solid phase extr action was developed and was found to result in an enrichment factor w ith a mean value of 9. Mono-adducts were characterized by intense [BH + H](+), [BH + Na](+) and [S](+) ion signals. Imidazole ring opening w as observed for the BPADGE/dGuo adduct indicating that the alkylation occurs at N-7. The alkylation site in the BPADGE/dCyd adduct was assig ned to N-3 because a hydrolytic deamination reaction was observed lead ing to the BPADGE/dUrd adduct. Cross-linking was not observed.