Separation and preconcentration of copper in environmental samples on Amberlite XAD-8 resin after complexation with a carbothioamide derivative

Abstract

Recebido em 16/10/12 ; aceito em 25/1/13; publicado na web em 14/5/13A new solid phase extraction (SPE) method has been developed for the selective separation and preconcentration of Cu (II) ions in food and water samples prior to its flame atomic absorption spectrometry determination. The method is based on the adsorption of the Cu(II)-2-{[4-Amino-3-(4-methylphenyl-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl]acetyl}-N-phenyl hydrazinecarbothioamide complex on Amberlite XAD-8 resin. The metal complex retained on the resin was eluted with 7.5 mL of 2.0 mol L −1 HCl in acetone. The optimum conditions for the SPE of Cu(II) ions were investigated, and the method was subsequently applied to sea water, stream water, rice, tea, and tobacco samples for the determination of Cu(II) levels.

Comparative study for the separation, preconcentration, and determination of copper and cadmium in real samples by using two different ligands

“…23−30 Additionally, adsorption capacity of the resin for Cu(II) and Cd(II) is broadly similar to that of some other methods in the literature. 14,23,24,26 When these two methods are compared with each other, both methods have the same optimum pH, but the second method has a high preconcentration factor. While the LOD of the second method is lower than that of the first method for Cd(II), the LOD of first method is lower for Cu(II).…”

“…23−30 Additionally, adsorption capacity of the resin for Cu(II) and Cd(II) is broadly similar to that of some other methods in the literature. 14,23,24,26 When these two methods are compared Table 5a. Spiked recoveries of Cu(II) and Cd(II) ions from solid samples (L1) (N = 3; pH 6.0; ligand concentration: 7.5 mg; eluent: 7.5 mL of 1.0 mol L −1 HCl in acetone; sample quantity: 0.750 g; and final volume: 2.0 mL).…”

Biological substrates: Green alternatives in trace elemental preconcentration and speciation analysis

“…As time went on, classical liquid-liquid extraction (LLE) techniques have been gradually replaced by SPE ones. They offer significant advantages over LLE, such as: i) higher recoveries; ii) higher enrichment factors, iii) improved selectivity, iv) specificity and reproducibility; v) less organic solvent and other reagents consumption (environmentally friendly); vi) shorter sample preparation time; vii) lower cost, easier operation and possibility of automation, viii) reusability of sorbents and ix) the possibility of coupling to different detection techniques [7,54].…”

“…For this reason, a previous preconcentration step is required in most analytical methods. Among traditional techniques, solid-phase extraction (SPE) is the most widely used for preconcentration of metals because it offers advantages such as high enrichment factors, low consumption of organic solvent/acids, and allows the development of flow methodologies, minimizing time of analysis and risk of contamination [7].…”

Microfluidic paper-based analytical devices coupled with coprecipitation enrichment show improved trace analysis of copper ions in water samples

“…Several separation-enrichment techniques have been reported for conventional instrumental analyses. These include preconcentration techniques such as liquid-liquid extraction, 18,19 membrane filtration, 20,21 microextraction, 22,23 cloud point extraction, [24][25][26] ion exchange, 27 solid-phase extraction (SPE), 28,29 and coprecipitation. 30,31 Some of the preconcentration techniques are also coupled with μ-PADs, which include a heating method, 32,33 ion concentration polarization, 34 and a pumping system.…”