cis-Diamminedichloroplatinum(II) (cisplatin) is applied against different kinds of cancer although toxic side effects are known. Screening systems for alternative compounds with higher effectiveness but minimizing toxic side effects are required. We investigated the adduct formation of cisplatin with nucleoside monophosphates, di- and trinucleotides. Capillary electrophoretic separations were performed in a sodium phosphate buffer using an instrument equipped with a diode array detector. Adduct formation results in a significant shift of lambda(max) to lower energy compared to free nucleotides. Therefore, UV spectra are an important tool for peak identification. We could separate and identify all four common nucleotides and their major platinum adducts in a single run demonstrating the suitability of CE for these kinds of investigations. Furthermore, kinetic studies of these reactions are performed.