A preliminary study of trace elements in plasma protein by gel chromatography combined with SXRF

Fractions of plasma protein of male Kunming mice (body weight 24.2±0.3g), treated with Cisplatin i.p. injection in dose of 10mg/kg, were obtained by separation on Sephadex-G-50 columns, buffered with ammonium acetate to pH 5.7. The SXRF experiments were performed at the BEPC (Beijing Electron Positron Collider) synchrotron radiation facility. The elements (Pt, S, Ca, Fe, Ni, Cu, Zn, Se, Br and Sr) in the fraction of the plasma proteins (< 22KD) were assayed using highly sensitive SXRF. The relative concentrations of elements were calculated by a normalization of Compton scattering intensity around 22 keV, after the normalization for collecting time of X-ray spectrum and the counting of the ion chamber, and subtracting the contribution of the polycarbonate film used for supporting the samples. The determination could prove that the element Pt in plasma was bound with macro-molecularprotein. Cu and S were present in the fraction of the protein in mice treated with Cisplatin and exhibited an increase, the ratio of treated/control were 1.66±0.06 and 1.78±0.33 respectively, whereas Zn decreased to a ratio of 0.78±0.09. Our results are in agreement with others which showed that Cisplatin exposure leads to a marked loss of kidney copper, and a moderate rise in kidney zinc. However, this work mainly focussed on the implementation of this analytical procedure, but not on the results of the investigations of the effect of Cisplatin on trace elements in plasma protein.