Hydride Generation-Atomic Fluorescence Spectrometric Determination of Lead in Agricultural Product with Micro-Wave Assisted Sample Digestion

Hydride generation-atomic fluorescence spectrometric method was applied to the determination of lead in agricultural products.The sample was dissolved with HNO3 and H2O2 in a tightly closed PTFE vessel and heated in a microwave oven under prescribed program.The sample solution was evaporated to near dryness and taken up with HCl(5+95).An intermittent flow hydride generation manifold was used in the generation of PbH4 and for separation of the gaseous mixture from the solution.Working conditions of the instrument and conditions of chemical reaction tested and optimized.Detection limit (S/N=3) of the method was 0.80 μg·L-1 Tests for precision and recovery were made,giving values of RSD′s (n=8) less than 10%,and recoveries in the range of 94.0%-113.5%.