Uncertainty Evaluation of Determination Results for Trace Leadin Monosodium Glutamate by Graphite Furnace Atomic Absorption Spectrometry

The uncertainty measurement of the trace Pb in monosodium glutamate samples by graphite furnace atomic absorption spectrometry (GFAAS) was evaluated in this paper. The results showed that the main sources of the total uncertainty came from the fraction uncertainties of sample weighting, calibration curve fitting, the certified values of standard reference materials, the instrument stability and etc.. The total uncertainty for the determination of lead by GFAAS was combined and the expanding uncertainty was calculated with value of 0.002×10-6for the monosodium glutamate sample with lead content of 0.025×10-6