Determination of silver in biological samples using graphite furnace atomic absorption spectrometry based on Zeeman effect background correction and matrix modification

A method for the determination of silver in human body fluids and biological material is described. The silver in an acid digest of biological samples and diluted body fluids is quantified using Zeeman graphite furnace atomic absorption spectrometry (ZGFAAS). The effects of NH4H2PO4 as matrix modifier and standard addition are discussed. Atomization from the graphite tube wall and from the pyrolytical tube with platform is also discussed and the peak height and the peak area are compared. The best results were achieved by using matrix modification, stabilized temperature platform furnace, integrated absorbance and standard addition technique. The calibration was linear up to 15 micrograms X L-1; the between-run precision was 5.9% at 40 micrograms X kg-1 of silver.