Preconcentration and Speciation of Sb(III) and Sb(V) in Water Samples and Blood Serum after Cloud Point Extraction Using Chemometric Tools for Optimization

A new Sb(III) and Sb(V) preconcentration and speciation method, optimized by multivariate design using cloud point extraction (CPE) with determination by graphite furnace atomic absorption spectrometry, is described. It is based on the formation of Sb(III) complexes with ammonium O, O- diethyl dithiophosphate (DDTP) in acid medium in the presence of Triton X-114. The Sb(V) is determined after quantitative reduction with L-cysteine, and its concentration is calculated by subtracting Sb(III) from the total antimony amount. The method provides a linear calibration range from 0.25 to 16.0g L-1 (r0.994) and limits of detection and quantification of 0.08g L-1 and 0.25g L-1, respectively. A high preconcentration factor was found to be 229-fold by preconcentrating 12.0mL of sample. The proposed method was successfully applied for the preconcentration and speciation of Sb(III) and Sb(V) in water samples and blood serum, where satisfactory recovery values were obtained, thus attesting to the feasibility of the method.