Clinical Chemistry, Vol 21, 891-893, Copyright © 1975 by the American Association for Clinical Chemistry

Correction for Spectral Interference with Determination of Lead in Blood by Non-Flame Atomic Absorption Spectrometry

V. P. Garnys ¹ and Jaroslav P. Matouek ¹

¹ Department of Analytical Chemistry, University of New South Wales, Sydney, N.S.W., Australia.

A non-flame atomizer incorporating a graphite tube and cup is used to determine lead in whole blood and packed erythrocytes. In a direct method, a 2-µl sample is treated in situ in the cup with 1 µl of concentrated nitric acid. The oxidized sample can then be dried, ashed, and atomized without leaving a residue. The nitric acid treatment obviates correction for nonselective absorption, something previously necessary in the determination of lead in blood by non-flame techniques. The resulting chemical conversion of the matrix compounds frees the lead atomic absorption peak from the spectral interference. Alternatively, a 50-µl sample of blood or erythrocytes is treated with 50 µl of concentrated nitric acid and a 1.5-µl aliquot is analyzed with use of the graphite tube.

Submitted on November 4, 1974
Accepted on March 10, 1975