Preparation and in-vivo evaluation of 99mTc-IOTIDA for cholescintigraphy.

The synthesis, radiolabeling and in vivo evaluation of 99mTc-IOIDA(3-iodo 2,4,6-trimethylpheyl carbamoylmethyl iminodiacetic acid) for the assessment of hepatocytic function and the functional status of the cystic duct and the gallbladder are described. For a scintigraphic imaging comparison, three different 99mTc-IDA derivatives, 99mTc-DISIDA, 99mTc-mebrofenin and 99mTc-IOTIDA, were prepared and evaluated for their in vivo pharmacokinetic behavior through animal studies. Serial static image scans of rabbits injected with 99mTc-IOTIDA revealed that none of the tissues except the hepatobiliary system showed radioactivity concentrations. A scintigraphic study in a healthy volunteer showed that most of the administrated radioactivity accumulated in the liver and was rapidly excreted through the hepatobiliary system, visualizing the gallbladder within 15 min. In conclusion, 99mTc-IOTIDA is a potential hepatobiliary imaging agent for the evaluation of the functional status of hepatocytes and the patency of the biliary duct.