Solidified floating organic drop microextraction for pre-concentration and trace monitoring of cadmium ions in environmental food and water samples

Abstract

In this research, solidified floating organic drop microextraction as an efficient sample preparation method was used for trace monitoring of cadmium ions in environmental samples. In this method, a free microdroplet of 1-undecanol is floated on the surface of aqueous solution and agitated by a stirring bar placed on the bottom of the sample vial. Cadmium ions were complexed with neocuproine to obtain hydrophobic complex and extracted to extraction solvent. The extracted target ions were determined by flow injection–flame atomic absorption spectrometry. The effect of important factors on the extraction of target ions by the proposed sample preparation method was evaluated and optimized. The limit of detection, relative standard deviation (%) and enrichment factor of the method were 0.02, 3.7 and 98.5%, respectively. The validation of the method was examined by the analysis of cadmium ions in the certified reference material (sea food mix), and the obtained data can proof the reliability of the method for trace detection of cadmium ions. The method was successfully applied for determination of cadmium in the real food and water samples, and satisfactory relative recoveries (97–102%) were achieved.