Synthesis and biological evaluation of novel technetium-99m-labeled HYNIC-D-glucose as a potential tumor imaging agent

A conjugate of 6-hydrazinopyridine-3-carboxylic acid (HYNIC) with the d-Glucosamine Hydrochloride (DG) was synthesized though a multiple-step reaction. HYNIC-DG could be labeled successfully and efficiently with Tc-99m using N-[2-hydroxy-1,1-bis(hydroxymethyl)ethyl]glycine (tricine) and ethylenediamine-N,N'-diacetic acid (EDDA) or tricine and triphenylphosphine-3,3',3aEuro(3)-trisulfonic acid trisodium salt (TPPTS) as co-ligands to form two Tc-99m-HYNIC-DG complexes Tc-99m-(t/E)HYNIC-DG and Tc-99m-(t/T)HYNIC-DG in high yields (> 95 %). The partition coefficient and electrophoresis results indicated they were very hydrophilic and electronegative. The biodistribution studies of two Tc-99m-HYNIC-DG complexes in Kunming mice bearing S 180 tumor showed that Tc-99m-(t/T)HYNIC-DG has more favorable characteristics than Tc-99m-(t/E)HYNIC-DG. High tumor uptake, low or negligible accumulation in non-target organs, and good retention, suggesting Tc-99m-(t/T)HYNIC-DG would be a novel potential tumor imaging agent.