Reaction of (SP-4-2)-dichlorobis(2-hydroxyethylamine)platinum(II) with 5′-GMP under simulated physiological conditions, a CZE-ESI-MS study

Capillary zone electrophoresis (CZE) has been applied for studying the binding behavior of the tumor inhibiting complex (SP-4-2)-dichlorobis(2-hydroxyethylamine)platinum(II) to the nucleotide 5′-GMP. Diode array UV detection enabled investigation of the time dependent behavior of 5′-GMP coordination under simulated physiological conditions. The binding behavior has shown to be dependent on the NaCl concentration as well as the pH value. For elucidation of the reaction pathway coupling of CZE to a mass spectrometer via an electrospray interface was applied. Contrary to common platinum complexes used in cancer therapy (e.g. cisplatin), the complex investigated forms a very stable monoadduct via intramolecular ligand attack reaction.