64Cu-ATSM

Cyclotron‐produced copper‐64 radioisotope tracers offer the possibility to perform both diagnostic investigation by positron emission tomography (PET) and radiotherapy by a theranostic approach with bifunctional chelators. The versatile chemical properties of copper add to the importance of this isotope in medicinal investigation. [64Cu][Cu (ATSM)] has shown to be a viable candidate for imaging of tumor hypoxia; a critical tumor microenvironment characteristic that typically signifies tumor progression and resistance to chemo‐radiotherapy. Various production and radiosynthesis methods of [64Cu][Cu (ATSM)] exist in labs, but usually involved non‐standardized equipment with varying production qualities and may not be easily implemented in wider hospital settings. [64Cu][Cu (ATSM)] was synthesized on a modified GE TRACERlab FXN automated synthesis module. End‐of‐synthesis (EOS) molar activity of [64Cu][Cu (ATSM)] was 2.2–5.5 Ci/μmol (HPLC), 2.2–2.6 Ci/μmol (ATSM‐titration), and 3.0–4.4 Ci/μmol (ICP‐MS). Radiochemical purity was determined to be >99% based on radio‐HPLC. The final product maintained radiochemical purity after 20 h. We demonstrated a simple and feasible process development and quality control protocols for automated cyclotron production and synthesis of [64Cu][Cu (ATSM)] based on commercially distributed standardized synthesis modules suitable for PET imaging and theranostic studies.

A review.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 pharmacol. 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.