Green method for the determination of Cd in rice and water samples based on electrolytic hydride generation and atomic fluorescence spectrometry

A simple, low cost and green method based on electrolytic reduction for hydride generation and atomic fluorescence spectrometry (AFS) was proposed for the determination of ultratrace amounts of cadmium in water and rice samples. The factors of electrolytic conditions such as cathode material, electrolytic current, enhancement reagents and catholyte on the signal intensity of Cd have been studied in detail. Ti foil was used as cathode material because of its efficacy of improving the response signal of cadmium. The electrolytic reducing product of cadmium was a molecular form of Cd, and the location for introducing carrier gas was an important factor that influenced the signal intensity of Cd greatly. Moreover, the potential interference and effective eliminating method was researched. Under the optimized conditions, the detection limit of Cd is 0.15 ng mL(-1); relative standard deviation of 3.0% for 20 ng mL(-1) Cd is obtained. The accuracy of the method is verified through analysis of the certificated reference materials (CRMs) and the proposed method has been applied to the determination of Cd in rice and water samples.