Dispersive liquid-liquid microextraction: An efficient approach for the extraction of Cd and Pb from honey and determination by flame atomic absorption spectrometry

In this work, the application of dispersive liquid-liquid microextraction (DLLME) for the extraction and preconcentration of Cd and Pb in honey and subsequent determination by flame atomic absorption spectrometry (FAAS) is proposed. Parameters such as type and volume of dispersive solvent (300 mu L., of acetonitrile for Cd and 900 mu L of acetone for Pb), type and volume of extraction solvent (140 mu L of carbon tetrachloride), concentration of complexing agent (sodium diethyldithiocarbamate, 025 g L-1 for Cd and 050 g L-1 for Pb), pH (7.0), temperature (35 degrees C), washing cycles of extract (2 times), centrifugation speed (840 g for Cd and 4600 g for Pb) and sample mass (500 mg) were evaluated. The limits of detection (LODs) were 20 and 140 ng g(-1) for Cd and Pb, respectively. These limits are lower than those established by the Brazilian Ministry of Agriculture, Livestock and Supply (500 ng g(-1) for both elements) for honey and for food in European Community. Samples were also digested in a microwave-assisted digestion system followed by element determination by inductively coupled plasma mass spectrometry (ICP-MS). Therefore, the proposed method is promising for routine analysis and quality control of Cd and Pb in honey. (C) 2015 Elsevier B.V. All rights reserved.