A SXRF method for determining the relative concentration of trace elementsin plasma protein affected by cisplatin

This article presents an analytical method for the determination of the rel ative concentrations of trace elements in plasma protein by gel chromatogra phy combined with SXRF (synchrotron radiation X-ray fluorescence). The frac tion of plasma protein of male Kunming mice (body weight 24.2 +/- 0.3 g), t reated with a cisplatin ip injection at a dose of 10 mg/kg, was obtained by the separation of a Sephadex G-50 column (buffered with ammonium acetate, pH 5.7). The SXRF experiments were performed at the Beijing Electron Positr on Collider synchrotron radiation facility. The elements (Pt, S, Ca, Fe, Ni , Cu, Zn, Se, Br, and Sr) in the fraction of the plasma proteins (>22 kDa) were assayed using highly sensitive SXRF. The relative concentrations of el ements were calculated by a normalization of Compton scattering intensity a round 22 keV, after the normalization for the collection time of the X-ray spectrum and the counting of the ion chamber, and subtracting the contribut ion of the polycarbonate film for the supporting sample. The determination could prove that the element Pt in plasma was bound with macromolecular pro tein. Cu and S were present in the fraction of the protein in mice treated with cisplatin increase, and their ratios of treated/control were 1.66 +/- 0.06 and 1.78 +/- 0.33, respectively; Zn decreased to a ratio of 0.78 +/- 0 .09. Our results are in agreement with others that cisplatin exposure leads to a marked loss of kidney copper and a moderate rise in kidney zinc. Howe ver, this article primarily describes one of the analytical methods used; i t does not emphasize the results of the effect of cisplatin on trace elemen ts in plasma protein.