Development of more efficacious Tc-99m organ imaging agents for use in nuclear medicine by analytical characterization of radiopharmaceutical mixtures

A comprehensive study of the electrochemical generation of Tc-MDP complexes at reticulated vitreous carbon is in progress. Results thus far indicate that high yields of the same complexes that are formed by electrochemical generation at mercury electrodes and by chemical reduction by NaBH4 at various values of solution pH are formed. Reticulated vitreous carbon offers the advantage of a flow through electrode with a large surface area for the rapid generation of Tc-MDP complexes at very low cost. It is a suitable electrode material for the proposed electrochemical syringe. A prototype TcO4- sensor has been fabricated by coating a graphite electrode with a thin film of the polymer poly(dimethyl-diallylammonium chloride). The polymer concentrates electroactive anions at the electrode surface as demonstrated with ferricyanide and thereby enhances the analytical signal for their detection. 2 figs