Synthesis, Radiolabeling and Biological Evaluation of 99mTc-labeled Deoxyglucose Derivatives for Molecular Imaging

Two deoxyglucose (DG) derivatives, (alpha,beta)-2-deoxy-2-amino(ethylcarbamate)-D-glucose (ECB-DG) and (alpha,beta)-2-deoxy-2-amino(1,2-dihydroxypropyl)-D-glucose (DHP-DG), were synthesized and radiolabeled successfully with [Tc-99m(H2O)(3)(CO)(3)](+) complex. [Tc-99m]-ECB-DG and [Tc-99m]-DHP-DG complexes were prepared (96% and 93% radiochemical purities respectively) by using 46 mCi of (NaTcO4)-Tc-99m in 1 mL saline. Radio-HPLC analysis of [Tc-99m]-ECB-DG at pH = 7.4, revealed that labeling with Tc-99m leads to formation of one radiochemical species with t(R) = 381 second. Three radiochemical species, (NaTcO4)-Tc-99m, [Tc-99m]-DHP-DG and [Tc-99m(H2O)(3)(CO)(3)](+) complexes with t(R) = 342 sec, t(R) = 567 sec and t(R) = 1586 sec respectively, were obtained when [Tc-99m]-DHP-DG complex evaluated by HPLC. Biodistribution of two complexes were studied on normal mice at 10, 30 and 60 min post-injections. Compared to the F-18-FDG, [Tc-99m]-ECB-DG displayed a 2.8-fold reduction in brain uptake (1.7 +/- 0.2 versus 0.61% +/- 0.09), whereas [Tc-99m]-DHP-DG just showed 1.9-fold reduction in heart uptake (2.2 +/- 0.05 towards 1.16 +/- 0.10) at 1 h post-injection. On the basis of our results, it seems that ECB-DG and DHP-DG analogues could be used as brain and heart imaging agent respectively.