SELECTIVE POTENTIOMETRIC DETERMINATION OF COPPER(II) IONS BY USE OF AMOLECULAR DEPOSITION FILM ELECTRODE BASED ON WATER-SOLUBLE COPPER PHTHALOCYANINE

A novel copper(II)-selective electrode was produced based on a molecul ar deposition technique in which water-soluble copper phthalocyanine t etrasulfonate was alternatively deposited with a bipolar pyridine salt (PyC(6)BPC(6)Py) on a 3-mercaptopropionic acid modified Au electrode. The potentiometric response is independent on pH of the solution betw een pH 1 and 5, while it is dependent on the nature of the medium. The electrode has a linear dynamic range between 1 x 10(-5) and 0.1 mol l (-1) with a Nernstian slope of 29 mV/decade concentration and a detect ion limit of 7 x 10(-6) mol l(-1) in acetate buffer (0.2 mol l(-1), pH 4.5). Except for Fe2+, Fe3+ and Co2+, Other common inorganic cations do not interfere in the determination of copper(II). The electrode has the advantages of low resistance, short conditioning time and fast re sponse.