INVESTIGATION OF LOW-MOLECULAR-WEIGHT PLATINUM SPECIES IN GRASS

The analysis of the low molecular weight fraction (<10 kDa) of platinu m species in grass is described. This fraction is isolated by ultrafil tration, gel-chromatography and preparative isotachophoresis and then further separated by Liquid chromatography with diode-array UV and pul sed amperometric detection. Platinum is determined in eluted fractions by using a very sensitive adsorptive voltammetric method. The strong correlation of platinum concentration with the highly selective pulsed amperometric detection enables the platinum binding ligands to be ide ntified as carbohydrate-oligomers (MW about 1 kDa). Further evidence o f this result is obtained by using capillary electrophoresis as an ind ependent separation technique. (C) 1998 Elsevier Science B.V.