Applications of radiocomplexes with thiosemicarbazones and bis(thiosemicarbazones) in diagnostic and therapeutic nuclear medicine

[Display omitted] •Radiolabeled metal complexes with thiosemicarbazones.•Radiolabeled metal complexes with bis(thiosemicarbazones).•Metal complexes with thiosemicarbazones in nuclear medicine.•Metal complexes with bis(thiosemicarbazones) in nuclear medicine. Metallic radionuclides possess a variety of half-lives, emission types, energies, and branching ratios, making it possible to apply them as diagnostic and/or therapeutic agents. Mono(thiosemicarbazones) and bis(thiosemicarbazones) show wide pharmacological profile and ability to chelate metals forming stable complexes. In the present work the behaviors of different radiometal complexes with mono(thiosemicarbazones) and bis(thiosemicarbazones) as diagnostic and therapeutic radiopharmaceutical drug candidates are reported. In particular, the applications of metal complexes with bis(thiosemicarbazones) as diagnostic radiopharmaceuticals have mostly been focused on bis(thiosemicarbazonato)copper(II) complexes, due to the success of the hypoxia-selective PET imaging agent 64Cu(ATSM), H2ATSM = diacetyl-bis(N4-methylthiosemicarbazone). However, metal complexes with mono- and bis(thiosemicarbazones) have also been obtained with other radioisotopes, mainly 67/68Ga, 111/114mIn and 99mTc. Some of these complexes have shown promising results in the search for new radiopharmaceuticals with applications in diagnosis and therapy.