PREPARATION, HPLC STUDIES AND BIOLOGICAL BEHAVIOR OF TC-99M-RADIOPHARMACEUTICALS AND TC-99MN-RADIOPHARMACEUTICALS BASED ON QUINOLINE TYPE LIGANDS

T-99m-Complexes of oxine (ox), thiooxine (tox) and 8-hydroxy-5-quinolinesulphonic acid (HQS) were prepared by ligand exchange of (TcNCl4-)-Tc-99m and by stannous and dithionite reduction of (TcO4-)-Tc-99m. HPLC studies showed that the (TcN-tox)-Tc-99m preparation was almost pure TcN(tox)2. (Tc(Sn)-ox)-Tc-99m yielded a number of peaks upon HPLC with the major peak being identified as TcO(ox)2Cl. No other Tc-complexes responsible for other chromatographic peaks were identified. Biodistribution studies in mice showed that all complexes except (Tc-HQS)-Tc-99m were cleared essentially by the hepatobiliary pathway. The (Tc-HQS)-Tc-99m preparations showed increased renal clearance due to the increased aqueous solubility of the complexes resulting from the presence of the sulphonate group on the quinoline ring.