PLATINUM SPECIES ANALYSIS IN PLANT-MATERIAL BY GEL-PERMEATION CHROMATOGRAPHY

Model experiments for the analysis of platinum species in extracts from native and platinum treated grass cultivation are described. The procedural steps are cultivation of the grass samples, preparative separation of the Pt species and analytical detection and characterisation of the separated species. The platinum uptake from the roots resulted by treating the grass cultivation with an aqueous solution of tetrammineplatinum(II) nitrate, [Pt(NH3)(4)](NO3)(2). The grass was cut, the cell fluid extracted and the Pt species were separated by gel permeation chromatography. The extremely sensitive adsorptive voltammetry was used for the sequential determination of platinum in the elution fractions. The estimation and determination of the molecular weights were carried out by gel permeation and liquid chromatography. In the native grass extract only one Pt species (160-200 kD) was detected. In the platinum treated grass extracts several Pt species were observed. More than 90% of all the platinum is bound to a low molecular weight species (about 1 kD), whereas less than 10% of the platinum is bound to species with molecular weights from 19 up to > 1000 kD.