A Tc-99-ADP complex was prepared when KTcO4 was reduced in aqueous med
ium by SnCl2, Na2S2O4, NaBH4 or Zn in the presence of ADP in excess. T
he resulting solution was studied by chromatography and spectrophotome
try. Electrochemical reduction and substitution on [Tc-III(tu)(6)](3+)
were investigated as alternative synthetic routes. The anionic Tc-ADP
complex was isolated as a solid. Cerimetric titrations confirmed the
oxidation state +3 for the central atom. IR and H-1-NMR data showed th
at the purine base is bonded to the Tc central atom but not the ribose
moiety. No oxo groups seemed to be directly bonded to the Tc atom. Th
e complex is rather stable in neutral solutions. However, it decompose
s to pertechnetate and TcO2 at extreme pH values.