FI-CV-AFS Determination of Mercury in Traditional Chinese Crude Drugs

Samples of traditional Chinese crude drugs were digested with HNO3 and H2O2 in closed vessel under pressure and heated in micro-wave oven.Aliquot portions of 1.0 mL of sample solutions were introduced with intermittent flow-injection mode into the AFS spectrometer and contents of mercury in micro amounts were determined by CV-AFS under the working conditions of the instrument described.Linear relationship between values of fluorescence intensity and concentration of mercury was obtained in the range within 25 μg·L-1,with detection limit(3S) of 0.02 μg·L-1.Ten samples of different crude drugs were analyzed by the proposed method.Values of RSD′s(n=7) calculated from the analytical results of mercury were all less than 5%,and values of recovery found by standard addition method were in the range of 97.2%-102.7%