Matrix-assisted laser desorption ionization time-of-flight mass spectrometry of DNA-Pt(II) complexes

Matrix‐assisted laser desorption ionization (MALDI) time‐of‐flight mass spectrometry has been used to characterize the reaction products of the 18‐mer deoxyribonucleotide d(AACGGTTAACCGTTAATT) with [Pt(NH3)3(H2O)]2+ and cis‐[Pt(NH3)2(H2O)2]2+. Characteristic peaks corresponding to different monofunctional adducts {18‐mer+n[Pt(NH3)3]} (n =1, 2, 3 and 4) have been observed with the triamino–monoaqua complex. With the diamino‐diaqua cis‐Pt complex, formation of a chelate {18‐mer+[Pt(NH3)2]} involving two adjacent guanines has been demonstrated. A good correlation between MALDI and polyacrylamide gel electrophoresis results is observed.