CHEMICAL AND BIOLOGICAL STUDIES OF TC-99M N,N'-BIS(MERCAPTOACETAMIDO)-ETHYLENEDIAMINE - A POTENTIAL REPLACEMENT FOR 1-131 LODOHIPPURATE

Abstract

The tetradentate chelating agent N,N''-bis(benzoylmercaptoacetamido)ethylenediamine was synthesized for evaluation as a potential 99mTc renal-function radiopharmaceutical. Complexes were prepared using different reducing agents and analyzed by high-performance liquid chromatography. Biological studies were performed in mice, rats and rabbits and indicated that the new agent is cleared by the kidneys significantly faster than 99mTc-DTPA [diethylenetriaminepentaacetic acid] (P < 0.01) and slightly slower than 131I-o-iodohippuric acid (P > 0.05). There was no evidence of significant renal retention. Renal excretion in all species studied was 70-75% of the injected dose in 30 min; biliary excretion in rats was 7% in animals with normal renal function and 18% in 90 min in the absence of renal function. Limited clinical trials are warranted.