Simultaneous Determination of As and Se in Chinese Yam Samples by Co-precipitation-Hydrid Genevation-Atomic Fluorescence Spectrometry

A method has been developed for simultaneous determination of arsenic and selenium in Chinese Yam samples by co-precipitation combining with hydride generation-atomic fluorescence spectrometry(HG-AFS).Various factors including type and amount of co-precipitation agents,pH value and concentration of KBH4 were investigated.With a sampling volume of 80 mL,the sensitivities for detection of arsenic and selenium were improved by 37.6 and 35.3 fold compared to conventional HG-AFS without preconcentration.Detection limits of 0.0007 μg/mL and 0.0007 μg/mL were obtained for arsenic and selenium with relative standard deviation of 1.05% and 0.77%,respectively.The method has been applied for the determination of trace arsenic and selenium in real samples with average recoveries of 95.4% and 90.6%.