SPECTROPHOTOMETRIC DETERMINATION OF COPPER(II) FOLLOWING COLLECTION ON AN ORGANIC SOLVENT-SOLUBLE MEMBRANE-FILTER AS THE N,NORMAL-DIETHYLDITHIOCARBAMATE COMPLEX

A highly sensitive, rapid and facile method is described for the determination of copper(II). A small amount of copper(II) is quantitatively collected on a membrane filter made of cellulose nitrate as a colored complex with N,N-diethyldithiocarbamate without carrier substances. The complex, together with the membrane filter, is dissolved in N,N-dimethylformamide (DMF), and the absorbance of the solution is measured for the determination. The calibration curve was linear from 0.1 to 8.8-mu-g of copper(II) in 3.0-cm3 DMF. The apparent molar absorptivity of copper(II) was 1.20 x 10(4) dm3 mol-1 cm-1. The relative standard deviations at 1.2 and 6.0-mu-g of copper(II) were 4.3% (n = 13) and 1.1% (n = 12), respectively. The method was applied to the determination of copper in environmental certified reference material (NIES No. 1, Pepperbush) and water samples.