Reactions of
cis-diamminedichloroplatinum(II) (cisplatin) and 1,1-cyclobutanedicarboxylatodiammineplatinum(II) (carboplatin) with reduced glutathione, a tripeptide that is abundant in cells, were studied by means of X-ray absorption spectroscopy. Back-scattering amplitudes
Fi(
k) and phase shifts Φ
i(
k) were theoretically derived, and validated by applying them to calculate extended X-ray absorption fine structure (EXAFS) oscillations of cisplatin and K
2[Pt(SCN)
4] in the solid state. EXAFS oscillations of reaction mixtures of cisplatin or carboplatin with reduced glutathione were fitted to the standard EXAFS equation using the
Fi(
k) and Φ
i(
k) functions to give the coordination numbers of N or O atoms (
NN/O) and of Cl or S atoms (
NCl/S). For both cisplatin and carboplatin, the
NN/O value decreased and the
NCl/S values increased monotonically as the reaction proceeded. However, the reaction rate for carboplatin was significantly slower than that for cisplatin.
抄録全体を表示