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

Abstract

A novel lipid emulsion (LE) was developed for hepatoselective 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 biodistribution and imaging profiles of the ITG-LE in rats. The concentration of radioactivity derived from intravenously administered 125I-ITG-LE was determined as a function of time after injection. CT imaging studies of the abdomen evaluated the extent of hepatic enhancement after administration of ITG-LE. Mean emulsion particle diameter and total administered dose exerted the greatest effect on ITG-LE biodistribution profiles. In the optimal delivery scenario, >70% of the administered dose localized to the liver 30 minutes after injection. Liver enhancement profiles in CT imaging studies were consistent with biodistribution profiles. These results suggest that an appropriately formulated and administered dose of ITG-LE provides tissue-selective localization of contrast material for use in CT.