Rapid determination of (carbon-14) glucose specific radioactivity for in vivo glucose kinetics

Specific radioactivity of blood glucose was determined by use of a Dowex-1 anion-exchange column after (carbon-14) glucose was infused for in vivo kinetics. The first 20-ml eluate of protein-free blood filtrate from the column was discarded; then 10 ml was collected, lyophilized, and counted in a liquid-scintillation counter. Glucose concentration was determined and specific radioactivity calculated. Kinetic results were comparable to those obtained with the more laborious glucose-pentaacetate procedure.