Newer methods of labeling diagnostic agents with Tc-99m

The past several years have seen marked advances in technetium/rhenium chemistry applicable to the preparation of new Tc-99m-labeled radiopharmaceuticals. This article focuses on recent developments in technetium chemistry, including the preparation of "3 + 1" complexes, the preparation and use of (Tc-99m[CO](3))(+) complexes for labeling biomolecules, the preparation of rhenium steroid inclusion complexes, improvements in both hydrazinonicotinamide labeling chemistry and in the preformed Tc-99m complex method of labeling biomolecules, and new solid-phase separation techniques that may allow the isolation of high specific-activity radiopharmaceuticals in a clinical setting. Copyright (C) 2001 by W.B. Saunders Company.