76Br-MBBG, a PET radiotracer to investigate the norepinephrine neurological and vesicular transproters in the heart

Expanding PET-applications in life sciences with positron-emitters beyond fluorine-18

Positron-emission-tomography (PET) has become an indispensable diagnostic tool in modern nuclear medicine. Its outstanding molecular imaging features allow repetitive studies on one individual and with high sensitivity, though no interference. Rather few positron-emitters with near favourable physical properties, i.e. carbon-11 and fluorine-18, furnished most studies in the beginning, preferably if covalently bound as isotopic label of small molecules. With the advancement of PET-devices the scope of in vivo research in life sciences and especially that of medical applications expanded, and other than "standard" PET-nuclides received increasing significance, like the radiometals copper-64 and gallium-68. Especially during the last decades, positron-emitters of other chemical elements have gotten into the focus of interest, concomitant with the technical advancements in imaging and radionuclide production. With known nuclear imaging properties and main production methods of emerging positron-emitters their usefulness for medical application is promising and even proven for several ones already. Unfortunate decay properties could be corrected for, and β+-emitters, especially with a longer half-life, provided new possibilities for application where slower processes are of importance. Further on, (bio)chemical features of positron-emitters of other elements, among there many metals, not only expanded the field of classical clinical investigations, but also opened up new fields of application. Appropriately labelled peptides, proteins and nanoparticles lend itself as newer probes for PET-imaging, e.g. in theragnostic or PET/MR hybrid imaging. Furthermore, the potential of non-destructive in-vivo imaging with positron-emission-tomography directs the view on further areas of life sciences. Thus, exploiting the excellent methodology for basic research on molecular biochemical functions and processes is increasingly encouraged as well in areas outside of health, such as plant and environmental sciences.

Evaluation of excitation functions of proton, ³He- and α-particle induced reactions for production of the medically interesting positron-emitter bromine-76

Cross section data for production of the medically interesting radionuclide ⁷⁶Br (T(½)=16.2 h) via the proton induced reactions on ⁷⁶Se, ⁷⁷Se, ⁷⁸Se and ⁷⁹Br, and ³He- and α-particle induced reactions on ⁷⁵As were evaluated. The nuclear model codes STAPRE, EMPIRE and TALYS were used to check the consistency in the experimental data and a statistical procedure was applied to derive the recommended excitation functions. A comparison of various production routes of ⁷⁶Br (and of ⁷⁵Br) is presented.