Preclinical assessment of 99mTc labeled liposome agents as an effective tracer in nuclear medicine.

Alkandari, Anfal Mohammad; Shafaa, Medhat Wahba; Alsayed, Yasser Mohammad

This study investigates the use of [Tc99m] liposome agents for the assessment of nuclear medicine purposes. A variety of [99mTc] liposome formulations were compared with common lymphoscintigraphic agents including [Tc99m] regular-sulfur colloid (SC), and [Tc99m] human serum albumin (HSA) besides assisting the use of positive charged liposomes in rabbits. 10 male rabbits (2-2.5 kg) were anesthetized with ketamine:xylazine intramuscularly. Then they were injected with different [Tc99m] liposome agents subcutaneously in the dorsum of each hind foot over the region of the metatarsals at the midline as well as intravenously. Dynamic (1 minute) scintigraphic images were acquired in a 256x1024 image matrix using a symbia gamma camera as early images and for the first 60 minutes post injection. This was followed by testing the tissue biodistribution by calculating the percentage of the injected dose (% ID) per organ for each (Tc99m) agent and studying the heart/liver, heart/bone marrow, and heart/kidneys ratio. All agents demonstrated good migration from the injection site to blood pool but not to lymphatic drainage. Agents were starting to clear out rapidly after 60 minutes. [Tc99m] liposome imaging can be used to develop novel liposome compositions with improved cardiac diagnostic and drug delivery characteristics.