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-exist ing 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 r elative standard deviations were less than 3.20%. The rate of recovery varied from 96.40 to 101.16%. The procedure was simple, rapid and rep roducible. The present study allows the determination of the amount of lithium in erythrocytes using electrothermal atomic absorption spectr ometry. In the 33 healthy subjects studied, the average concentration of lithium in erythrocytes was 13.70 +/- 1.56 mu g l(-1).