The determination of thallium is of great interest because of its clinical and environmental roles as well as industrial applications. Thallium is highly toxic to the biosphere even more than Hg, Cd, Pb and Cu[1]. Imprinted polymers are biomimetic materials used for sensitive and selective detection of analyte 350 molecules. They are much more stable to organic solvents, pH, high temperature and pressure than their biological counterparts. Moreover, these materials are cheap to be produced and stored in dry state at room temperature for long periods of time. With such benefits, the technology has found a niche in various techniques including solid phase extraction applications[2]. In this study, thallium (I)-ion imprinted polymer as a new sorbent has been synthesized for the first time. This sorbent was used for SPE and preconcentration of thallium(I) ions from aqueous solution.The thallium(I)-imprinted polymer joined with dispersive liquid–liquid microextraction (DLLME) has been developed as an ultra preconcentration technique for determination of thallium(I) in water samples. In ion imprinted polymer(IIP)–dispersive liquid–liquid microextraction (IIP–DLLME), thallium(I) are adsorbed from a large volume of aqueous samples (100 mL) into 100 mg ion imprinted polymer sorbent followed by the elution of the desired compounds from the sorbent by using nitric acid and adopted to DLLME.Various experimental parameters e.g. pH, uptake time, desorption time, IIP weight, aqueous phase volume and HNO3 desorption volume were examined for ion imprinted polymer. Factors affecting the dispersive liquid–liquid micro-extraction procedure such as pH, the concentrations of crown ether and picric acid,the nature and volume of the extraction and disperser solvents and extraction time were studied. The percentage recovery of thallium was calculated from the FAAS results.At the optimized conditions, the detection limit was found to be 1.5 ng mL1. The relative standard deviation for five replicate analysis of 30 ng mL1 of thallium (III) was 2.1%. The method was applied to determine thallium in a certified reference material and spiked tap water to demonstrate the accuracy, relative recovery and applicability of the presented method. The proposed technique is simple, convenient, selective and efficient.

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