Reactor production of ~(32)P for medical applications: an assessment of ~(32)S(n,p)~(32)P and ~(31)P(n,γ)~(32)P methods

摘要

The article describes a comparative study carried out on the reactor production of ~(32)P by two different processes, namely, ~(32)S(n,p)~(32)P and ~(31)P(n,γ)~(32)P with a view to determine the merits and bottlenecks of each method and assess the usefulness of ~(32)P obtained from each of the processes. In a typical batch, 250 g of elemental sulfur when irradiated at a fast neutron flux of ~8 × 10~(11) n cm~(-2) s~(-1) for 60 days, after chemical processing provided about 150 GBq(4.05Ci) of ~(32)P having specific activity of 200TBq(5500Ci)/mmole. On the other hand, irradiation of 0.35 g of red phosphorus at a fast neutron flux of ~7.5 × 10~(13) n cm~(-2) s~(-1) for a period of 60 days gave 75 GBq(2.02Ci) of ~(32)P of specific activity 7 GBq(190mCi)/ mol~(-1). While the specific activity of ~(32)P obtained from ~(32)S(n,p)~(32)P is superior to that obtained from the ~(3l)P(n,γ)~(32)P process, the requirement of elaborate target processing steps involving distillation and purification emerged as a deterrent that limits its widespread adaptability. Both the production routes offer ~(32)P of acceptable quality amenable for medical applications although their specific activity differs.