Monoanionic 99mTc-tricarbonyl-aminopolycarboxylate complexes with uncharged pendant groups: Radiosynthesis and evaluation as potential renal tubular tracers

New tracers lacking the negatively charged pendant carboxyl group previously thought to be essential for rapid renal extraction, Tc(CO)(ADA), Tc(CO)(HDA) and Tc(CO)(FEDA), exhibit pharmacokinetics in rats comparable to those of Tc(CO)(NTA) and I-OIH. Furthermore, these encouraging results in rats warrant evaluation of this new tracer type in humans.