Direct determination of lithium in erythrocytes by electrothermal atomic absorption spectrometry.

A method for the direct determination of lithium in erythrocytes using 0.2 mol l-1 K2HPO4-1% Triton X-100 solution as a matrix modifier is described. The optimum experimental parameters and effect of co-existing elements on the determination of lithium has been investigated in detail. The detection limit for lithium was 5.0 x 10(-11) g, and the relative standard deviations were less than 3.20%. The rate of recovery varied from 96.40 to 101.16%. The procedure was simple, rapid and reproducible. The present study allows the determination of the amount of lithium in erythrocytes using electrothermal atomic absorption spectrometry. In the 33 healthy subjects studied, the average concentration of lithium in erythrocytes was 13.70 +/- 1.56 micrograms l-1.