Determination of Antimony from Polyethylene Terephthalate in Drinking Water by Solid Floating Organic Drop Microextraction and Electrothermal Atomization Atomic Absorption Spectrometry

Trace antimony in drinking water leached from polyethylene terephthalate bottles was determined by solidified floating organic drop microextraction for preconcentration prior to electrothermal atomization atomic absorption spectrometry. The antimony formed an anionic complex with iodide in the presence of sulfuric acid. Didecyl dimethyl ammonium chloride was used to form a hydrophobic ion association complex that was extracted using a drop of 1-dodecanol. All significant parameters affecting the analytical performance were studied. Under the optimum conditions, the enhancement factor was 331. The limit of quantification and precision were 0.04ng/mL and 2.46% (n=9, 1.0ng/mL), respectively. The accuracy of the developed method was evaluated by analyzing a certified reference material. The optimized method was employed for the determination of Sb(III) in water stored in polyethylene terephthalate bottles. The effects of factors affecting antimony transfer such as storage time, exposure to ultraviolet light, and temperature were characterized.