Determination of selenium in tea leaves by microwave digestion and Atomic Fluorescence Spectroscopy

The operation of the closed and high pressure microwave digested the tea with HNO3-H2O2,Iron potassium cyanide was used as screening agent,then determined by atomic fluorescence spectrometer. The result showed the microwave digestion was convenient,fast,little interference by base and with better control throughout the whole digestion process. The detection limits for selenium was 0.0858 μg/L. The relative standard deviation for Se was 1.17%. The recovery for Se was in the rang of 94.0%～107.1%,and the correlation coefficient was 0.9994.