Dosimetric analysis of the contribution of Radionuclides Coproduced through natV(p,x)47Sc reaction route in Cyclotron Irradiation

Scandium presents different radionuclides with good imaging and therapeutic properties for the development of theranostic radiopharmaceuticals. In particular, 47Sc (t1/2= 3.35 d) has suitable features both for SPECT imaging, thanks to the 159 keV γ-ray emission, and for treatment of small-size tumours, thanks to the intense β− emission (mean β− energy: 162.0 keV). Its efficacy has been demonstrated at preclinical stage, but its low availability has however limited the application of 47Sc-based radiopharmaceuticals to the clinic. Among the different proposed production routes, the natV(p,x)47Sc nuclear reaction is of particular interest, due to the low-cost and easy availability of the target material, as well as the widespread availability of medium-energy cyclotrons. However, the nuclear cross section of this reaction is quite low and small amounts of Sc radioactive contaminants are co-produced. The aim of this work is to evaluate the contribution of Sc-contaminants to the patient radiation dose.