ESMS and NMR investigations on the interaction of the anticancer drug cisplatin and chemopreventive agent selenomethionine

The reactions of L-selenomethionine (L-Se-MetH) with cisplatin, cis-[PtCl2(NH3)(2)], were investigated using electrospray mass spectroscopy (ESMS) and 2-D [H-1-N-15] NMR spectroscopy. The reaction intermediates and products identified were cis-[PtCl(L-Se-MetH)(NH3)(2)](+), cis-[Pt(L-Se-Met)(NH3)(2)](+), [PtCl(L-Se-MetH)(NH3)](+) and [Pt(L-Se-Met)(L-Se-MetH)](+). Some binuclear adducts were also detected by ESMS during the reaction, although they existed in minor amounts. Similar reactions with L-MetH were also conducted under similar conditions for comparison. This work provides the first detailed studies on the reaction of a platinum-based drug with L-Se-MetH.