Dispersive liquid-liquid microextraction for the determination of cadmium, palladium and gold elements in several environmental samples by faas

In this study, the usage of three organic ligands, in separation and preconcentration of some ions such as Cd2+, Pd2+ and Au3+ by dispersive liquid liquid microextraction (DLLME), has been evaluated with FAAS detection. The analytical factors affecting the microextraction efficiency, such as the pH, amount of ligand, type and volume of dispersive solvent, type and volume of extraction solvent, sample volume, standing time, centrifugation rate and time were investigated. From the obtained results, it was seen that, 2-[(4-phenyl-5-thioxo-4,5-dihydro-1,3,4-oxadiazol-2-yl)methyl]-5-methyl-4-[2-(1H-indol-3-yl)ethylated]-2,4-dihydro-3H-1,2,4-triazol-3-one (L1) can be used for selective separation and preconcentration of Cd2+ ions at pH 6.5; with 1-(6-morpholino pyridine-3-yl)-3-phenyl thiourea (L2), Au3+ at pH 5.5 and Pd2+ at pH 1.5; with N-(Benzyl)-2-({3-methyl-5-oxo-4.2-(1H-indol-3-yl)ethyl]-4,5-dihydro-1H-1,2,4-triazol-1-yl} acetyl) hidrazinkarbotiyoamid (L3), Au3+ ions at 0.2 mol L-1 of HNO3. The limit of detection (LOD) were found 0,69 µg L-1 for cadmium, 4,97 µg L-1 for palladium, and 4,86-4,97 µg L-1 for gold. The enrichment factor was 40 for Cd2+, was 20 for Au3+ ve Pd2+. The spike tests and the certified reference material applications were used for the accuracy testing of improved methods. The developed methods were applied to environmental solid samples such as ore, food, plastic, cigarette, tobacco and liquid samples such as sea, stream and drinking water).