111In-phenolphthalexon, a new chelate for extended cholescintigraphy: formulation and preclinical characterization

The first 111In chelate exhibiting hepatobiliary excretion, a 111In-phenolphthalexon, has been formulated and tested in rats. The preparation of the chelate is simple, reflecting its inherently high stability. Its capability for extended cholescintigraphy allowed distinct visualization of the gallbladder and the bowel to the level of the rectosigmoid in dogs. No lethality or acute toxicity was induced by administration of the chelate.