Dosimetry of 51MnCl2 and 52MnCl2 for PET application

Manganese has been so far mainly used for in-vivo animal studies of tissue anatomy of liver, kidneys, heart and pancreas, as well as to monitor cellular activity, cytoarchitecture and neuronal tract tracing in the brain by using the so-called Manganese-Enhanced Magnetic Resonance Imaging (MEMRI)-based techniques. However, the large amount of manganese necessary for MEMRI may induce neurotoxic effects that result in manganism, a neurological syndrome similar to Parkinson\u2019s disease. The much higher sensitivity of positron emission tomography (PET) over MRI enables, instead, the use of non-toxic trace level concentrations of Mn. The radioisotopes 52Mn (t1/2= 5.591 d, \u3b2+= 29.4%, E(\u3b2+)avg= 241.6 keV) and 51Mn (t1/2= 45.59 min, \u3b2+=97.1%, E(\u3b2+)avg = 970.2 keV) have already been used for preclinical PET imaging in the past, mainly administered in free ionic form as MnCl2 1-2. However, internal radiation dose assessment due to the administration of 52MnCl2 to humans is still missing, while only one study has been reported for 51MnCl2 dosimetry calculations2. The aim of this work is to fill this gap by assessing the radiation effective dose (ED) of 51MnCl2 and 52MnCl2

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 \u3b3-ray emission, and for treatment of small-size tumours, thanks to the intense \u3b2 12 emission (mean \u3b2 12 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