The rates of fast reactions of carbon dioxide and bicarbonate in human erythrocytes measured by carbon-13 NMR.

The application of carbon-13 nuclear magnetic resonance spectroscopy to the study of the kinetics of millisecond timescale reactions of CO2 in human erythrocyte suspensions is described. The rates of intracellular enzyme catalyzed CO2 hydration and HCO3- dehydration were quantitatively determined, as well as the rates of CO2 diffusion into and out of the erythrocytes. The method also provides an accurate measure of the intracellular pH in the range of pH 6.0 to pH 7.0. A temperature dependence study was used to determine the thermodynamic functions for the intracellular hydration-dehydration reaction.