Polyiodinated triglyceride analogs as potential computed tomography imaging agents for the liver

A series of glyceryl 2-oleoyl 1,3-bis[omega-(3-amino-2,4,6-triiodophenyl)] alkanoates was synthesized, radioiodinated with iodine-125, emulsified, and evaluated for their ability to selectively localize in the liver for potential use as hepatographic agents in computed tomography. All seven analogs displayed rapid liver uptake wherein between 65 and 78% of the injected dose accumulated in the liver by 30 min. Liver values ranged from 46 to 93% 3 h after injection which corresponded to liver to blood ratios ranging from 21 to 450. Moreover, subsequent elimination of radioactivity from the liver was nearly linear with respect to alkyl chain length. Analogs with longer alkyl chain length were eliminated from the liver more rapidly than their shorter chain counterparts. Because of their biochemical similarities to naturally occurring triglycerides, these novel analogs may prove useful not only for high-resolution anatomic imaging of focal liver lesions, but also for evaluating a variety of diffuse diseases known to affect hepatic function and biochemistry.