Procurement and biological significance of pure 11C-glucose

Biological significance of 11C-glucose purity has been a controversial matter. In order to understand the contribution of impurities contained in the photosynthetic 11C-glucose, its analysis and biodistribution in mice was studied. Studies indicated the interference of impurities, particularly 11C-fructose in the injectate, with the quantitative evaluation of glucose metabolic rate in brain. Furthermore, results obtained offered a good basis for search of simpler and easier separation methodology. Namely, good selection and combination of commercially available high performance liquid chromatography (HPLC) column provided 11C-glucose with high radiochemical purity. The radiochemical yield achieved was 6-10% at 75 min after the end of bombardment including the HPLC purification. The imaging study by positron computed tomography in a rabbit showed the suitability of 11C-glucose as a radiopharmaceutical for the diagnosis of the brain function.