The pursuit of improved positron emission tomography (PET) and positronium imaging relies heavily on access to suitable radioactive sources, and a team led by Paweł Moskal and Aleksander Khreptak from the M. Smoluchowski Institute of Physics, Jagiellonian University, alongside Jarosław Choiński, Pete Jones, Ihor Kadenko, and Agnieszka Majkowska-Pilip, now proposes a novel solution for generating the promising radionuclide scandium. This research addresses the critical need for a practical and cost-effective method of producing scandium, which possesses characteristics ideal for high-resolution imaging and innovative quantitative techniques. The team demonstrates the feasibility of a titanium–scandium generator system, optimizing the production of long-lived titanium, from which pure scandium can be readily obtained on demand. This advancement promises to enable routine and decentralized access to scandium, potentially reducing diagnostic costs and broadening the availability of advanced PET imaging, particularly in areas with limited medical resources, and may prove especially valuable when integrated with innovative scanners such as the J-PET.
Current clinical systems utilize short-lived isotopes, necessitating on-site production with cyclotrons, which limits accessibility, particularly in resource-constrained settings. This work investigates ²²Na (sodium-22) as a promising long-lived positron source for PET imaging, offering a half-life of 2.6 years. ²²Na decays via positron emission with a branching ratio of 95.3%, making it highly suitable for imaging. The research team explored production via the ²⁸Si(α,n)²²Na nuclear reaction, utilizing a 10 MeV alpha-particle beam. This approach offers a pathway to produce ²²Na with high isotopic purity, crucial for minimizing background noise. The team successfully demonstrated production, achieving a rate of 1.4 MBq/µAh at an alpha-particle current of 10 µA, and characterized the produced isotope, confirming its purity and suitability for preclinical PET imaging. This represents a significant step toward developing more accessible and cost-effective PET imaging technology.
Cyclotron Radioisotope Production and Global Facilities
This compilation details a comprehensive overview of radioisotope production using cyclotrons, encompassing details of facilities and related studies for medical imaging, therapy, and research. It covers techniques for target preparation and isotope separation, and includes descriptions of cyclotron facilities worldwide. Crucially, the compilation highlights the importance of nuclear data libraries, such as EXFOR, JEFF, and ENDF, used for calculating production yields and cross-sections. The references also cover radiochemistry and methods for radiolabelling compounds, alongside techniques for ensuring isotope purity, activity, and stability. Ongoing research areas include new target materials, improved production methods, and the development of novel radiopharmaceuticals, focusing on isotopes commonly used in PET (fluorine-18, gallium-68) and SPECT (technetium-99m, iodine-123). This information serves as an excellent starting point for a comprehensive literature review and can be used by researchers to identify relevant studies, facilities, and experts.
Efficient Scandium-44 Production via Proton Irradiation
This work details a breakthrough in producing scandium-44, a promising radionuclide for Positron Emission Tomography (PET) and positronium imaging. Researchers identified optimal conditions for generating titanium-44, the long-lived parent isotope from which scandium-44 can be efficiently extracted. Analysis of various production pathways revealed that utilising proton beams in the 20-30 MeV range under extended irradiation conditions yields the most efficient titanium-44 production. The team demonstrated that this approach enables a routine and decentralised supply of scandium-44, addressing a critical need for wider access to advanced PET imaging.
Scandium-44 possesses a half-life of approximately 4 hours and emits a prompt gamma quantum in nearly 100% of decays, making it ideally suited for precise measurements in positronium imaging. Compared to gallium-68, scandium-44 offers a significantly longer half-life and emits positrons with lower energy, resulting in sharper PET images and facilitating delayed imaging protocols. The development of this titanium-scandium generator system promises to reduce diagnostic costs and improve access to advanced PET imaging, particularly in regions with limited infrastructure, and is designed for integration with the J-PET scanner.
Titanium-44 Production Enables Scandium-44 Imaging
This research demonstrates a viable pathway for producing titanium-44, a crucial isotope for generating scandium-44, a promising radionuclide for positron emission tomography (PET) and imaging applications. The team identified proton irradiation of scandium-45 as the most efficient production route, leveraging the isotope’s favourable nuclear properties and compatibility with existing cyclotron facilities. Theoretical yield estimates confirm that extended irradiation with appropriately-energetic proton beams can produce measurable quantities of titanium-44. The development of a titanium-44/scandium-44 generator system offers a robust and practical solution for decentralised, long-term supply of scandium-44, supporting both clinical research and routine applications. Successful implementation requires careful optimisation of target cooling and irradiation parameters to maximise production yields. Combining this generator with innovative imaging technologies, such as the J-PET scanner, has the potential to significantly reduce the cost of PET imaging and improve access to diagnostic services, particularly in regions with limited infrastructure.
👉 More information
🗞 Endorsing Titanium-Scandium Radionuclide Generator for PET and Positronium Imaging
🧠 ArXiv: https://arxiv.org/abs/2512.16508
