The use of stable radioisotopes for metabolic studies in man
Lefebvre, P.
Pathologie-Biologie 24(5): 303-305
1976
ISSN/ISBN: 0369-8114 PMID: 781599 Document Number: 99614
Stable (nonradioactive) isotopes like 13C can be isolated in large quantities and are also present in nature in somewhat greater than normal proportions in certain plant materials. For many metabolic experiments in humans (including pregnant women), such stable isotopes can be used safely, since they are nonradioactive. While the proportion of 13C in atmospheric CO2 is usually 1.1%, the sugar biosynthesis of certain plants (as sugar cane and corn) has special features that result in cane and corn sugar being naturally a little richer in 13C, compared with C in atmospheric CO2. By administering such sugars to humans participating in metabolic studies, the air breathed by these subjects will be slightly richer in 13C than ordinarily. This difference can be measured by the new devices not requiring radioactive elements or artificial sources of stable isotopes.