Simultaneous first derivative spectrophotometric determination of copper(II) and nickel(II) using 1-phenyl-1,2-propanedione-2-oxime thiosemicarbazone

Oil Technological Research Institute, JNTU, Anantapur-515 001, Andhra Pradesh, India

Department of Chemistry, Sri Krishnadevaraya University, Anantapur-515 003, Andhra Pradesh. India

Manuscript received 15 July 2005, revised 27 January 2006. accepted 20 February 2006

The reagent, 1-phenyl-1,2-propanedione-2-oxime thiosemicarbazone (PPDOT) has been used for the determination of Cu^ll and Ni^ll by spectrophotometric method. The reagent gives intense colour reactions with copper(ll) and nickel(ll) in sodium acetate-acetic acid burrer medium. Maximum colour intensity is observed in the pH range 3.0-8.0. The molar absorptivity and Sandell's sensitivity of the methods for the determination of copper(ll) and nickel(ll) are 0.575 x 10⁴, 1.20 x 10⁴ L mol^-l cm^-1 and O.Oll8 and 0.00503 μg cm^-2 respectively. The compositions of copper and nickel complexes of PPDOT as determined by Job's and molar ratio methods are found to be l : 2 (M : L). First derivative methods have been developed for the determination of Cu^ll and Ni^ll. Simultaneous spectrophotometric determination of Cu^ll and Ni^ll carried out by measuring the peak-base line technique at 500 and 467.5 nm respectively. The method is carried out without the need for employing simultaneous equations in the determination of Cu^ll and Ni^ll in synthetic mixtures and in edible oils and seeds.