Isotopic differences in the lithium transport rate in human erythrocytes during simultaneous incubations with the stable isotopes 6Li and 7Li.

The membrane transport of the two stable lithium isotopes, 6Li and 7Li, by erythrocytes has been studied using a dual channel atomic absorption spectroscopic technique. 6Li appears to be taken up preferentially to 7Li, in the ratio of 10 to 40%, depending on the concentration of total lithium and on the lithium isotopic ratio in the external medium.