A convenient solution-phase method for the preparation of meta-iodobenzylguanidine in high effective specific activity

Synthesis of Radioiodinated Compounds. Classical Approaches and Achievements of Recent Years

This review demonstrates the progress in the synthesis of radioiodinated compounds over the past decade. The possibilities and limitations of radiopharmaceuticals with different iodine isotopes, as well as the synthesis of low and high molecular weight compounds containing radioiodine, are discussed. An analysis of synthesis strategies, substrate frameworks, isolation methods, and metabolic stability, and the possibility of industrial production of radioiodinated organic derivatives which can find applications in the synthesis of drugs and diagnostics are presented.

Radiobromine and radioiodine for medical applications

The halogens bromine and iodine have similar chemical properties and undergo similar reactions due to their closeness in Group 17 of the periodic chart. There are a number of bromine and iodine radionuclides that have properties useful for diagnosis and therapy of human diseases. The emission properties of radiobromine and radioiodine nuclides with half-lives longer than 1 h are summarized along with properties that make radionuclides useful in PET/SPECT imaging and β/Auger therapy, such that the reader can assess which of the radionuclides might be useful for medical applications. An overview of chemical approaches that have been used to radiolabel molecules with radiobromine and radioiodine nuclides is provided with examples. Further, references to a large variety of different organ/cancer-targeting agents utilizing the radiolabeling approaches described are provided.

A convenient method for the preparation of radioiodinated meta-iodobenzylguanidine at a no-carrier-added level

Radioiodinated meta-iodobenzylguanidine (MIBG) in high effective specific activity was prepared using 3-tributylstannylbenzylguanidine as the precursor. The labeling was carried out in aqueous solution with the insoluble and lyophilized precursor suspended in the solvent. Simply by filtration, the starting material and by-products were readily separated from the labeled solution. Less than 1.15 ppb tin has remained in the filtrate as determined by the atom fluorescence spectrometry. By this approach, high specific activity (3.4 GBq/µmol) [(131)I]MIBG was obtained in 72.3 ± 3% (n = 3) radiochemical yield and 97.3 ± 2% (n = 3) radiochemical purity. The whole preparation could be finished in less than 10 min. According to this method, a kit for the preparation of (123)I-MIBG and (131)I-MIBG is currently being developed.

Establishment of a fast and high yield method for routine production of [(131) I]MIBG and investigation of its radiochemical stability for diagnosis and treatment uses

In this work, exchange radioiodination of metaiodobenzylguanidine (MIBG) was carried out at optimum conditions that facilitates the production of [(131) I]MIBG both quickly and efficiently. The radiochemical purity and yield of the labeled product are typically as high as 99% and 90% for diagnostic dose and 95% and 80% for therapeutic dose, respectively. Stability studies show that labeled material at the room temperature met the demand of the clinical application. This labeling procedure will be used in the routine production process of [(131) I]MIBG for diagnosis and treatment uses.