Spectrophotometric and thermodynamic study for Separation and preconcentration of Trace Amounts of Selenium Species After CPE

Abstract

Abstract A new prepared chelating agent namely, 2-(Benzimidazolyl azo-4-benzyl phenol) (BIABP) is used for the determination of selenium species in water, rice and vegetables samples by a combination of cloud point extraction (CPE) method and spectrophotmetric techniques. The method involved a selective hydrophobic complex formation between selenium (IV) (and selenium (VI) after reduction with HCl under specified conditions) and (BIABP) at pH 5 which can efficiently be extracted in surfactant-rich phase of Triton X-114 and determined sepectrophotometrically at λmax of 534 nm. All significant factors for selenium (IV) complex that impact the separation and determination steps were discussed in detail by one factor-at-a-time (OFAT) optimization. The interferences and thermodynamic studies are also considered. At optimum conditions, the enrichment factor of 58 fold was obtained for Se (IV), leading to detection limits of 2.55 ng Se (IV) mL−1. The linear dynamic range, relative standard deviation (n=7 at 30 ng Se (IV), and the percent recovery were of 5-80 ng mL−1, 1.07% and 97.83±1.40. The described method is sensitive, easy to apply and has a slight interferences thereby the determination of selenium species in water, rice and vegetables samples was performed.