Production of nitrogen-13-labeled ammonia by using 11MeV medical cyclotron: our experience

A method has been developed for the production of (13)N-labeled ammonia in usable quantities with negligible contamination. A system was developed and a process for the production of nitrogen-13 ammonium ions from a target material in the form of a dilute solution of ethanol in natural water, i.e. the bombardment of oxygen-16 with protons within the target material. The system includes a device for producing a proton beam which travels along a pre selected path and strikes the target material in a target chamber. This target chamber is positioned in the path of the proton beam such that subjection of the target material to the beam produces nitrogen-13 atoms and alpha particles. These nitrogen-13 atoms are converted in the aqueous solution to ammonium ions and oxides and are conducted from the target holder to a purification cartridge for collecting a purified product containing the ammonium ions.