Simultaneous determination of the amounts of Na and K inside single human erythrocytes was accomplished by laser vaporization and monitoring the atomic emission produced. By using a modified sheath-flow arrangement, detection of 8 fg (0.35 fmol) of Na is possible with one laser pulse. By using Poisson statistics, one can obtain single-cell information even when multiple cells are vaporized per laser pulse. The intracellular contents for a given individual were found to vary significantly. The ±55% and ±155% variations for Na and K, respectively, cannot be explained by changes in cell volume. There is only a weak correlation between the Na and K contents in single cells. The results reflect the age distribution of erythrocytes in the sample. Presumably, the enzymes regulating ion transport lose their activities in the older cells.
Scopus Subject Areas
- Analytical Chemistry