Atomic Fluorescence Spectrometry Determination of Mercury in Corn

HG-AFS was applied to the determinations of mercury in corn with microwave assisted sample digestion.The flow rates of carrier gas and shielded gas,concentration of potassium borohydride,electrical current of lamp,and interferences of the coexisting ions were studied and optimized.Linear relationship between the fluorescence intensity and mass concentration of Hg was found in the range within 20 μg·L-1,with detection limit of 0.02 μg·L-1.The proposed method was applied to the analysis of 5 corn samples,and values of recovery found by standard addition method were in range of 90.0% to 102.5%,with values of RSD′s (n=10) less than 4%.