CONTRAST MATERIAL-CARRYING LIPOSOMES - BIODISTRIBUTION, CLEARANCE, AND IMAGING CHARACTERISTICS

PURPOSE: To assess the biodistribution, clearance, and computed tomogr aphic (CT) imaging characteristics of interdigitation-fusion (IF) lipo somes that carry iotrolan in their aqueous phases. MATERIALS AND METHO DS: Biodistribution and clearance of liposomes containing iotrolan pro duced with the IF method (IF vesicles) were assessed in rats. CT scans of rats and dogs were obtained after injection of IF vesicles at 100 and 250 mg of iodine per kilogram of body weight. RESULTS: A high init ial uptake (63%-96% of the injected dose) was found in the liver and s pleen. Liver elimination Showed half-lives to be 12.9 days at 250 mg o f iodine per kilogram, 10.9 days at 100 mg, and 8.7 days at 25 mg. At 250 mg of iodine per kilogram, the rats had an average of 96 HU of hep atic and 321 HU of splenic enhancement. The dogs had 116 HU of hepatic and 65 HU of splenic enhancement. CONCLUSION: IF liposomes have favor able biodistribution, clearance, and imaging characteristics as hepato splenic contrast agents.