Terminally sterilized alpha-emitting isotope generator and method for producing terminally sterilized alpha-emitting isotope

A terminally sterilized isotope generator for producing a 212Pb daughter isotope by emanation of Radon-220 (220Rn) gas from a parent isotope, the isotope generator comprising:

• a parent-isotope chamber, divided into a lower zone initially loaded with the parent isotope onto a sponge or glass wool, and an upper zone extending above the lower zone, the lower zone and the upper zone being in fluid communication with each other, the parent-isotope chamber having a gas outlet port in the upper zone;
• a daughter-isotope chamber for collecting the 212Pb daughter isotope, the daughter-isotope chamber having a gas inlet port in an upper zone of the daughter-isotope chamber;
• a controllable gas duct, connected between the gas outlet port and the gas inlet port, the controllable gas duct being configurable between an open configuration fluidly connecting the gas outlet port of the parent-isotope chamber to the gas inlet port of the daughter-isotope chamber, and a closed configuration fluidly isolating the gas outlet port of the parent-isotope chamber from the gas inlet port of the daughter-isotope chamber;
• an eluent dispenser, configured to deliver an eluent;
• a controllable eluent duct having three ends;
• a first end in fluid communication with the eluent dispenser to receive the eluent;
• a second end in fluid communication with the parent-isotope chamber;
• and
• a third end in fluid communication with the daughter-isotope chamber,
• wherein the controllable eluent duct is configurable between a loading configuration fluidly connecting the first end to the third end to fill the daughter-isotope chamber with the eluent and to elute in a liquid form the 212Pb daughter isotope generated in a gaseous form, and a mix configuration fluidly connecting the second end to the third end to allow remaining 220Rn to circulate from the daughter-isotope chamber to the parent-isotope chamber;
• and
• a collection container, in fluid communication with an outlet port located in a lower zone of the daughter-isotope chamber, configured to collect the 212Pb daughter isotope eluted in a liquid form from the daughter-isotope chamber,
• wherein the parent-isotope chamber further comprises a first actuator for creating a vortex, wherein when actuated, the vortex created initiate generation of 220Rn in a gaseous form, the 220Rn naturally decaying from 224Ra, and force the 220Rn in a gaseous form to circulate in the upper zone of the parent-isotope chamber through the gas outlet port, to the controllable gas duct in the open configuration, to the gas inlet port and then to the daughter-isotope chamber;
• wherein the daughter-isotope chamber further comprises a second actuator for creating a vortex, wherein when the controllable gas duct in the closed configuration and when actuated, the vortex created initiate a generation of 212Pb in a gaseous form, the 212Pb naturally decaying from 220Rn, where 212Pb in a gaseous form is extracted by the eluent and carried to the collection container through the outlet port,
• wherein the isotope generator is scalable based on a required 212Pb daughter-isotope quantities to be generated, the required 212Pb daughter-isotope quantities range from 1 mCi to 500 mCi.

A method for producing terminally sterilized pure alpha-emitting daughter isotope, comprising the steps of:

• delivering a parent isotope into a parent-isotope chamber of a closed retainer assembly for initiating a 220Rn emanation process by natural decay of the parent isotope in the parent-isotope chamber;
• transferring the 220Rn in a gaseous form into a daughter-isotope chamber, through a gas permeable membrane separating the parent-isotope chamber and the daughter-isotope chamber, the gas permeable membrane allowing the 220Rn to passively pass therethrough under an action of gravity or diffusion;
• generating a 212Pb daughter isotope by natural decay of 220Rn in the daughter-isotope chamber;
• circulating an eluent in the daughter-isotope chamber, to elute the 212Pb daughter isotope generated in a gaseous form;
• collecting the 212Pb daughter isotope eluted in a liquid form from the daughter-isotope chamber into a collection container;
• and
• sealing the collection container filled of the 212Pb daughter isotope with a daughter isotope cap plug, to ensure sterilized collection container and maintain closed collection container integrity.