Polyiodinated triglyceride lipid emulsions for use as hepatoselective contrast agents in CT - Effects of physicochemical properties on biodistribution and imaging profiles

RATIONALE AND OBJECTIVES. A novel lipid emulsion (LE) was developed for hep atoselective delivery of a polyiodinated triglyceride (ITG) with potential for use in CT, This work assessed the effects of mean particle size, total administered dose, and formulation composition on the in vivo biodistributi on and imaging profiles of the ITG-LE in rats. METHODS. The concentration of radioactivity derived from intravenously admi nistered I-125-ITG-LE was determined as a function of time after injection, CT imaging studies of the abdomen evaluated the extent of hepatic enhancem ent after administration of ITG-LE, RESULTS. Mean emulsion particle diameter and total administered dose exerte d the greatest effect on ITG-LE biodistribution profiles. In the optimal de livery scenario, >70% of the administered dose localized to the liver 30 mi nutes after injection. Liver enhancement profiles in CT imaging studies wer e consistent with biodistribution profiles. CONCLUSIONS. These results suggest that an appropriately formulated and adm inistered dose of ITG-LE provides tissue-selective localization of contrast material for use in CT.