PRECONCENTRATION OF COPPER TRACES ON C-60-C-70 FULLERENES BY FORMATION OF ION-PAIRS AND CHELATES

The adsorptive potential of C-60 and C-70 fullerenes for the preconcen tration of copper traces was assessed for the first time in this work, The method used for this purpose involves the formation, adsorption o n a fullerene minicolumn, and elution with 250 mu L of methyl isobutyl ketone of various ion pairs or chelates of copper. A sample loading t ime of 2 min provides an enrichment factor for copper between 40 and 1 85 relative to direct introduction of aqueous solutions into an atomic absorption spectrometer. The effect of concurrent cations was investi gated in order to optimize the best chemical system (ion pairs or chel ate) for the determination of copper. The systematic study carried out in this work allows us to conclude that the best selectivity and sens itivity are achieved with chelate formation and sorption on C-70 fulle rene.