Determination of Trace Selenium in Teas by Atomic Fluorescence Spectrometry

Selenium element in teas can be determined by atomic fluorescence spectrometry.The method was described for the eliminating the interference of Pb~(2+)、Cu~(2+)、Ag~(+)with the enrichment of sulfhydryl cotton and thiourea ascorbic acid.The optimum determination conditions were tested and discussed.The linear range and detection limit were 0.00～100.00 ng·mL~(-1) and 0.57 ng·mL~(-1) respectively.The rate of recovery varied from 99.0 % to 106.3%,and the RSD was less than 1.71%.