Imaging of alpha particles and X-rays emitted from actinium-225 and its daughter radionuclides using a perovskite structure scintillator: YAP(Ce) based radiation imaging detector

Actinium-225 (Ac-225) holds substantial promise as an alpha emitter for targeted radionuclide therapy, yet precise, energy-resolved imaging of its alpha particles and X-rays has been a challenge. Here we show a perovskite-structure scintillator: YAP(Ce) based detector, achieving advancements in energy-resolved imaging. For alpha particle detection, the system reached a spatial resolution of 1 mm with an energy resolution of 8% for 8.38 MeV alpha particles, enabling clear differentiation of 4 energy peaks of Ac-225 and its daughter radionuclides. In imaging with X-rays with an energy range of approximately 80 keV to 100 keV, the detector achieved a spatial resolution of 1.6 mm, enabling detailed visualization of phantoms. These findings underscore the potential of YAP(Ce)-based detector as a tool for the imaging required in developing Ac-225 radiopharmaceuticals.