Speciation of Antimony Using Dithizone Ligand via Cloud Point Extraction and Determination by USN-ICP-OES

Abstract

In this paper, a cloud point extraction (CPE) method is described and inorganic antimony species were determined by using an inductively coupled plasma optic emission spectrometer coupled to an ultrasonic nebulizer (USN-ICPOES). Dithizone complexed Sb(III) species were trapped in the micelle front the aqueous phase using the Triton X-114 surfactant with an increase in temperature. After centrifugation and phase separation, the surfactant-rich phase was dissolved with 2 M HNO3 and measured in the USN-ICP-OES. Indium (In) was used as an internal standard in order to reduce noise and random systematic errors. The effects of phi, surfactant concentration, ligand concentration, heating time, temperature, and interfering ions were optimized. The effects of the rate of foreign ions and their species, as well as the parameters such as pH, surfactant concentration, ligand concentration, heating time and temperature, were optimized. In the proposed method, Sb(V) was reduced to Sb(III) with L-cysteine for the determination of total antimony. For Sb(III), the determined 1.01) value was 0.04 mu g with an RSD of 2.59% (n=12) [pH = 4, 0.04 mu g mol L-1 dithizone, and 0.06% (w/v) Triton X-114]. The developed method was applied to the analysis of real water and fruit juices, and validated using a certified reference material.