Determination of copper from environmental samples by solvent microextraction method using AAS. Multivariate modelling and factorial design

Abstract

ABSTRACT The dispersive liquid–liquid microextraction methods were developed, based on the enrichment and separation of copper after complexation with bis(salicylaldehyde)ethylenediamine (H2SA2en) from environmental samples. The quantitation was made by the flame atomic absorption spectrometric methods. The effect of parameters pH, derivatising reagent (H2SA2en) concentration, the volume, extracting solvent, disperser solvent, centrifugation time and temperature on analytical signals and the extraction efficiency of metal ion was examined and optimised using univalent and multivalent (factorial design) techniques. The linearity of calibration curve was in the range of 5–30 ng/ml with R 2 = 0.9907. Limit of detection was 2.0 ng/ml and limit of quantification was 6.0 ng/ml, and the enrichment factor (21.5), repeatability (n = 4) and robustness of the determination were also evaluated. Method was effectively employed for the estimation of copper from the samples of water and sediments. Samples were collected from Darawat Dam and River Indus. The results obtained were matched with reported methods, and comparable sensitivity and selectivity was indicated.