Determination of Trace Copper(II) in Food Samples by Flame Atomic Absorption Spectrometry after Cloud Point Extraction

Document Type : Research Article

Authors

School of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou City, P.R. CHINA

Abstract

A new method for the determination of trace copper(II) in food samples by Cloud Point Extraction(CPE) combined with Flame Atomic Absorption Spectrometry(FAAS) is presented and evaluated. The method is based on the fact that hydrophobic complex of copper(II) with sodium diethyldithiocarbamate (DDTC) was formed at pH 6.0 and subsequently the hydrophobic complex was extracted into surfactant-rich phase. Copper(II) in surfactant-rich phase was analyzed by FAAS after dilution the surfactant-rich phase to 0.5 mL by nitric acid in methanol(0.1 mol L-1). The main factors affecting CPE, such as pH, concentration of DDTC and Triton X-114, equilibrium temperature and incubation time, sample volume were investigated in detail. The effect of coexisting ions on the recovery of copper(II) was also investigated. Under the optimum conditions, the detection limit(3σ) of this method was 1.1 ng mL-1 for copper(II), and the relative standard deviation was 3.4 % (c=100 ng mL-1, n=7). The analytical results for the certified reference tea sample(GBW07605) were in a good agreement with the certified value. The proposed method was successfully applied to determination of trace copper(II) in milk powder and mineral water with satisfactory results.

Keywords

Main Subjects


[1] Kendüzler E., Türker A.R., Atomic Absorption Spectrophotometric Determination of Trace Copper in Waters, Aluminium Foil and Tea Samples After Preconcentration with 1-Nitroso-2-Naphthol-3,6-Disulfonic Acid on Ambersorb 572, Anal. Chim. Acta, 480, p. 259 (2003).
[2] Ghiasvand A.R., Ghaderi R., Kakanejadifard A., Selective Preconcentration of Ultra Trace Copper(II) Using Octadecyl Silica Membrane Disks Modified by a Recently Synthesized Glyoxime Derivative, Talanta, 62, p. 287 (2004).
[3] Rumori P., Cerdà V., Reversed Flow Injection and SandwichSequential Injection Methods for the Spectrophotometric Determination of Copper (II) with Cuprizone, Anal. Chim. Acta, 486, p. 227 (2003).
[4] Szigeti Z., Bitter I., Toth K., Latkoczy C., Fliegel D.J., Gunther D., Pretsch E., A Novel Polymeric Membrana Electrode for the Potentiometric Anylisis of Cu2+ in Drinking Water, Anal. Chim. Acta, 532, p. 129 (2005).
[5] Tuzen M., Soylak M., Citak D., Ferreira H.S., Korn M.G.A., Bezerra M.A., A Preconcentration System for Determination of Copper and Nickel in Water and Food Samples Employing Flame Atomic Absorption Spectrometry, J. Hazard. Mater., 162, p. 1041 (2009).
[6] Ferreira H.S., SantosA.C.N., PortugalL.A., Costa A.C.S., Miro M., Ferreira S.L.C., Pre-Concentration Procedure for Determination of Copper and Zinc in Food Samples by Sequential Multi-Element Flame Atomic Absorption Spectrometry, Talanta, 77, p. 73 (2008).
[7] Vinas P., Pardo-Martinez M., Hernandez-Cordoba M., Determination of Copper, Cobalt, Nickel, and Manganese in Baby Food Slurries Using Electrothermal Atomic Absorption Spectrometry, J. Agric. Food Chem., 48, p. 5789 (2000).
[8] Mitic S.S., Micic R.J., Simonovic R.M., Analytical Application of Food Dye Sunset Yellow for the Rapid Kinetic Determination of Traces of Copper(II) by Spectrophotometry, Food Chem., 117, p. 461 (2009).
[9] Faraji M., Yamini Y., Shariati S., Application of Cotton as a Solid Phase Extraction Sorbent for
On-Line Preconcentration of Copper in Water Samples Prior to Inductively Coupled Plasma Optical Emission Spectrometry Determination, J. Hazard. Mater., 166, p. 1383 (2009).
[10] Vassileva E., Quetel C.R., Certification Measurement of the Cadmium, Copper and Lead Contents in Rice Using Isotope Dilution Inductively Coupled Plasma Mass Spectrometry, Anal. Chim. Acta, 519, p. 79 (2004).
[11] Citak D., Tuzen M., Soylak M., Simultaneous Coprecipitation of Lead, Cobalt, Copper, Cadmium, Iron and Nickel in Food Samples with Zirconium(IV) Hydroxide Prior to Their Flame Atomic Absorption Spectrometric Determination, Food Chem. Toxicol., 47, p. 2302 (2009).
[12] Tuzen M., Citak D., Soylak, M., 5-Chloro-2-Hydroxyaniline-Copper(II) Coprecipitation System for Preconcentration and Separation of Lead(II) and Chromium(III) at Trace Levels, J. Hazard. Mater., 158, p. 137 (2008) .
[13] Xie F.Z., Lin X.C., Wu X.P., Xie Z.H., Solid Phase Extraction of Lead (II), Copper (II), Cadmium (II) and Nickel (II) Using Gallic Acid-Modified Silica Gel Prior to Determination by Flame Atomic Absorption Spectrometry, Talanta, 74, p. 836 (2008).
[14] Anthemidis A.N., Ioannou K.I.G., On-Line Sequential Injection Dispersive Liquid-Liquid Microextraction System for Flame Atomic Absorption Spectrometric Determination of Copper and Lead in Water Samples, Talanta, 79, p. 86 (2009).
[15] Fathi S.A.M., Yaftian M.R., Cloud Point Extraction and Flame Atomic Absorption Spectrometry Determination of Trace Amounts of Copper(II) Ions in Water Samples, J. Colloid. Interface Sci., 334, p. 167 (2009).
[16] Chen J.G., Chen H.W., Chen S.H. Lin L., Zhong Y.Y., Determination of Ultratrace Amounts of Copper (II) in Water Samples by Electrothermal Aomic Absorption Spectrometry After Cloud Point Extraction, Chem. Res. Chinese U., 23, p. 143 (2007).
[17] Tatara E., Materna K., Schaadt A., Bart H.J., Szymanowski J., Cloud Point Extraction of Direct Yellow, Environ. Sci. Technol., 39, p. 3110 (2005).
[18] Bellato A.C.S, Gervasio A.P.G., GinéM F., Cloud-Point Extraction of Molybdenum in Plants and Determination by Isotope Dilution Inductively Coupled Plasma Mass Spectrometry, J. Anal. At. Spectrom., 20, p. 535 (2005).
[19] Silva E.L., Roldan P.S., Simultaneous Flow Injection Preconcentration of Lead and Cadmium Using Cloud Point Extraction and Determination by Atomic Absorption Spectrometry, J. Hazard. Mater., 161, p. 142 (2009).
[20] Stalikas C.D., Micelle-Mediated Extraction as a Tool for the Separation and Preconcentration in Metal Analysis, Trends Anal. Chem., 21, p. 343 (2002).
[21] Şatıroğlu N., Çiğdem, A., Cloud Point Extraction for the Determination of Trace Copper in Water Samples by Flame Atomic Absorption Spectrometry, Microchim. Acta, 162, p. 107 (2008).
[22] Manzoori J.L., Bavili-Tabrizi A., The Application of Cloud Point Preconcentration for the Determination of Cu in Real Samples by Flame Atomic Absorption Spectrometry, Microchem. J., 72, p. 1 (2002).
[23] Lemos A., Me-BTABr Reagent in Cloud Point Extraction for Spectrometric Determination of Copper in Water Samples, J. Braz. Chem. Soc., 17, p. 30 (2006).
[24] Chen J.R., Teo K.C., Determination of Cadmium, Copper, Lead and Zinc in Water Samples by Flame Atomic Absorption Spectrometry After Cloud Point Extraction, Anal. Chim. Acta, 450, p. 215 (2001).
[25] Shemirani F., AbkenarS.D., Khatouni A., Determination of Trace Amounts of Lead and Copper in Water Samples by Flame Atomic Absorption Spectrometry After Cloud Point Extraction, Bull. Korea. Chem. Soc., 25, p. 1133 (2004).
[26] Lemos V.A., Santos M.S., Dos Santos M.J.S., Vieira D.R., Novaes C.G., Determination of Copper in Water Samples by Atomic Absorption Spectrometry After Cloud Point Extraction, Microchim. Acta, 157, p. 215 (2007).
[27] Shemirani F., Jamali M.R., Kozani R.R., Salavati-Niasari M., Cloud Point Extraction and Preconcentration for the Determination of Cu and Ni in Natural Water by Flame Atomic Absorption Spectrometry, Sep. Sci. Technol., 41, p. 3065 (2006).