一种新型脑灌注显像剂^(99m)TcN-CPDTC的制备及生物分布

Preparation and Biodistribution of the ~ (99m)TcN-CPDTC Complex as a New Potential Brain Perfusion Imaging Agent

The complex 99m TcN CPDTC(CPDTC: N cyclopropyl dithiocarbamate trihydrate) is synthesized through ligand exchange reaction. The two step procedure involves the initial reaction of 99m TcO - 4 with succinic dihydrazide(SDH) as a donor of nitrido ligand(N 3- ) in the presence of stannous chloride dihydrate as reducing agent and propylenediamine tetraacetic acid(PDTA) as complex agent, followed by the addition of sodium N cyclopropyl dithiocarbamate trihydrate. The radiochemical purity(RCP) of the product is over 90% as measured by thin layer chromatography(TLC). It is stable over 6 h at room temperature. Its partition coefficient indicates it is a good lipophilic complex. The biodistribution results in mice indicate that 99m TcN CPDTC is significantly retained into the brain. The brain uptake(%, ID/g) is 4.64, 3 54 and 2.59 and the brain/blood ratio is 1.08, 1.27 and 1.28 at 5, 30 and 60 min post injection respectively. These results suggest potential usefulness of the complex as a brain perfusion imaging agent.