Radiolabeled liposomes as metabolic and scanning tracers in mice. II. In-111 oxine compared with Tc-99m DTPA, entrapped in multilamellar lipid vesicles.

We describe the organ distribution of positively and negatively charged multilamellar lipid vesicles (MLV) labeled with Tc-99m DTPA or In-111 oxine in mice. The organ distribution of MLV (In-111 oxine) is fairly constant throughout 72 hr, indicating that the radiotracer remains associated with cellular structures at the site of MLV uptake. In animals injected with MLV (Tc-99m DTPA), on the other hand, there is continuous leakage of radioactivity from the involved organs.