Differential pulse polarographic determination of copper in alloys and biological samples after preconcentration with 2-nitroso-1-naphthol-4-sulphonic acid-tetradecyldimethylbenzylammonium-naphthalene adsorbent

Copper is quantitatively retained on 2-nitroso-1-naphthol-4-sulphonic acid- terradecyldimethylbenzylammonium (TDBA(+))-naphthalene adsorbent packed in a chromatographic column in the pH range 7.1-10.7 at a flow rate of 2 mL/mi n from a large volume of its aqueous solution of various alloys and biologi cal samples. The metal complex is desorbed with 1 M hydrochloric acid and d etermined by differential pulse polarography (DPP). The detection limit is 0.25 mu g/mL (signal to noise ratio = 2) and the linearity is maintained in the concentration range 0.7 - 28.0 mu g/mL with a correlation coefficient of 0.9994 and relative standard deviation of +/- 0.88%. Characterization of the electroactive process included an examination of the degree of reversi bility. Various parameters such as the effect of pH, volume of aqueous phas e and interference of a large number of metal ions on the determination of copper have been studied in detail to optimize the conditions for its deter mination in various alloys and biological samples. The method may also be a pplied for the determination of copper in various environmental samples.