Potential radiopharmaceuticals for the diagnosis of biliary atresia and neonatal hepatitis: EHPG and HBED chelates of 67Ga and 111In.

Radiopharmaceuticals suitable for use in cases where delayed excretion of hepatobiliary tracer can occur, were formulated from indium-111 and gallium-67 and the chelating agents N,N'-ethylene-bis-[o-hydroxy-phenylglycine], (EHPG) and N,N'-bis-[2-hydroxybenzyl] ethylenediamine-N,N'-diacetic acid, (HBED). The hepatobiliary excretion of these 67Ga and 111In chelates was optimised by using chelators which had substituents in the phenolic ring; halogen substituents imparted the most favourable characteristics.