Pore-Filled Scintillating Membrane as Sensing Matrix for α‑Emitting Actinides

Pore-filled membranes with scintillating properties have been synthesized for sensing α-emitting radionuclides. The membranes have been prepared by in situ UV-initiator-induced polymerization of monomer bis­[2-(methacryloxy)­ethyl] phosphate in pores of the host membranes, poly­(propylene) and poly­(ethersulfone). The polymerization has been carried out in the presence of scintillating molecules, 2,5-diphenyloxazole. These scintillating molecules are physically trapped in the thus formed microgel in the membrane. Much higher α-scintillation efficiency has been obtained for the 241Am-loaded poly­(ethersulfone)-based grafted membrane compared to poly­(propylene)-based membrane. This was attributed to the aromatic backbone of the poly­(ethersulfone) membrane. The scintillation response of poly­(ethersulfone)-based membranes has been found to be linear over the range of 241Am activity studied. The pore-filled scintillating membranes have been found to be selective toward Pu4+ ions at higher HNO3 concentration compared to Am3+. The analytical performance of the pore-filled scintillating membranes has been evaluated. The membranes have been found to be stable and reusable. The scintillating membrane with optimized composition has been applied for quantification of Pu in a soil sample.