Preparation and biodistribution of 99mTc-labeled tyramine iminodiacetic acid

The synthesis and biodistribution properties of 99mTc-labeled N-substituted tyramine, [N-(4-hydroxyphenethyl)iminodiacetic acid] are described. Tissue distribution studies in rats were indicative of high hepatic and kidney extraction, accompanied by rapid plasma and urinary clearance and minimal biliary excretion. These findings were substantiated by organ image analysis. The preliminary data indicate that this labeled material may represent a new class of radiopharmaceuticals for the evaluation of hepatic and renal functions.