Determination of total thallium in water and spinach samples by ligandless microextraction using ion pair-based dispersive liquid-liquid microextraction followed by electrothermal atomic absorption spectrometry

摘要

An efficient, simple, and sensitive ligandless, ion pair-based dispersive liquid-liquid microextraction technique was used for preconcentration and determination of trace levels of total thallium followed by electrothermal atomic absorption spectrometry. In this method, thallium(III) was complexed by bromide ion to produce negative charged thallium bromide complex followed by addition of cetylpyridinium chloride as a counterion to form hydrophobic complex which was extracted into the extraction solvent by DLLME. In this method, a mixture of 1.5 mL of methanol (as disperser solvent) containing 150 mu L of chloroform (as extraction solvent) was injected as extractant.