New strategies for a sustainable Tc supply to meet increasing medical demands: Promising solutions for current problems.

The continuing rapid expansion of Tc diagnostic agents always calls for scaling up Tc production to cover increasing clinical demand. Nevertheless, Tc availability depends mainly on the fission-produced Mo supply. This supply is seriously influenced during renewed emergency periods, such as the past Mo production crisis or the current COVID-19 pandemic. Consequently, these interruptions have promoted the need for Tc production through alternative strategies capable of providing clinical-grade Tc with high purity. In the light of this context, this review illustrates diverse production routes that either have commercially been used or new strategies that offer potential solutions to promote a rapid production growth of Tc. These techniques have been selected, highlighted, and evaluated to imply their impact on developing Tc production. Furthermore, their advantages and limitations, current situation, and long-term perspective were also discussed. It appears that, on the one hand, careful attention needs to be devoted to enhancing the Mo economy. It can be achieved by utilizing Mo neutron activation in commercial nuclear power reactors and using accelerator-based Mo production, especially the photonuclear transmutation strategy. On the other hand, more research efforts should be devoted to widening the utility of Mo/Tc generators, which incorporate nanomaterial-based sorbents and promote their development, validation, and full automization in the near future. These strategies are expected to play a vital role in providing sufficient clinical-grade Tc, resulting in a reasonable cost per patient dose.