Analysis of nucleoside-estrogen adducts by LC-ESI-MS-MS†

Abstract

Liquid chromatography coupled with tandem mass spectrometry (LC-MS-MS) has been used for the assessment of the reactivity of estradiol-2,3-quinone towards deoxyribonucleosides in crude reaction mixtures. The use of LC-MS-MS allowed the direct injection of crude reaction mixtures, thus avoiding tedious sample preparation and purification steps before the mass spectrometric analysis of the prepared adducts. Several original (sometimes minor) adducts could be evidenced with deoxyguanosine and a new addition product has been characterized in the reaction of estradiol-2,3-quinone with deoxycytidine. Multisequential MSⁿ mass spectrometry performed on a quadrupole ion-trap mass spectrometer enabled the discrimination of isomeric adducts present in crude reaction mixtures. These results show that LC-MS-MS is a very powerful analytical tool for the detection and characterization of adducts in crude reaction mixtures.