In the last decade, the development of new radiopharmaceuticals for the imaging and therapy of prostate cancer has been a highly active and important area of research, especially focusing on the prostate‐specific membrane antigen (PSMA), an antigen which is upregulated in prostate, as well as in other tumor cells. A large variety of PSMA ligands have been radiolabeled, to date. Among the various derivatives, PSMA‐617 resulted to be one of the most interesting in terms of interaction with the antigen and clinical properties, and its lutetium‐177 labeled version has recently been approved by regulatory agencies for therapeutic purposes. For this reasons, the radiolabeling with fluorine‐18 of a PSMA‐617 derivative might be of interest. Beside other methodologies to radiolabel macromolecules with fluorine‐18, the “click‐chemistry” approach resulted to be very useful, and the copper‐catalyzed azide‐alkyne cycloaddition (CuAAC) is considered one of most efficient and reliable. This paper proposes the synthesis of a suitable precursor for the radiolabeling with fluorine‐18 of a new PSMA‐617 derivative. The whole radiosynthetic procedure has been fully automated, and the final product, which proved to be stable in plasma, has been obtained with radiochemical yield and purity suitable for subsequent preclinical studies.

As an effort to improve F-radiolabeling of biomolecules in method robustness and versatility, we report the synthesis and radiolabeling of a new azido precursor potentially useful for the so-called "click reaction," in particular the ligand-free version of the copper(I)-catalyzed alkyne-azide cycloaddition. The new azido precursor may help to overcome problems sometimes exhibited by most of the currently used analogues, as it is safe to handle and it displays long-term chemical stability, thus facilitating the development of new radiolabeling procedures. Moreover, the formed F-labeled 1,2,3-triazole is potentially metabolically stable and could enhance the in vivo circulation time. The above azido precursor was successfully radiolabeled with F, with 51% radiochemical yield (nondecay-corrected). As a proof of concept, the F-labeled azide was then tested with a suitable alkyne functionalized aminoacid (l-propargylglycine), showing 94% of conversion, and a final radiochemical yield of 27% (>99% radiochemical purity), nondecay-corrected, with a total preparation time of 104 minutes.

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The increasing research and engineering of pure copper in the field of experimental nuclear physics is motivated by its outstanding physical properties making such material the key constituent of many types of detectors and particle accelerators. The Italian Research Institute on Nuclear Physics (INFN -Istituto Nazionale di Fisica Nucleare) is in charge of research in this field and, taking advantage of its expertise in the field of additive manufacturing (AM), has equipped the HAMMER (https://hammer.lngs.infn.it/) Lab with a 3D printer, characterized by a powder bed together with a laser beam, in order to evaluate the possibility of producing pure copper objects compatible with the requirements of experimental apparatuses using Selective Laser Melting (SLM) technique and specific post-processing thermal treatments. Notwithstanding the growing request of pure copper components realized via AM processes techniques, their processability via SLM technology is still challenging due to the high reflectivity of copper at the emission wavelength of the conventional SLM laser sources (1064 nm) along with the thermal issues resulted from copper's high conductivity. This work aims to verify the quality of parts produced in pure Cu in terms of density and mechanical properties as well as to evaluate the effect of heat treatments during post-processing, in order to achieve the highest consolidation for the material and, thus, improved functional properties.

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