Radioactive 32P Research Articles

Since Szilard and Chalmers prepared the carrier-free radiohalogens from the organohologen compouds in 1934, the Szilard-Chalmers method has been applied to the separation of radioisotopes in a high specific activity. In order to prepare silicon-31 and phosphorus-32 in a high specific activity, the authors investigated the process with tributyl phosphate as the target material. Tributyl phosphate was bombarded with neutron by the cyclotron (neutron flux: 107n/cm2.sec), and radioactive 31Si and 32P formed were extracted from tributyl phosphate with the various kinds of extracting reagents. The percentage yield of separated 31Si activity showed the maximum value 87.5% when potassium hydroxide-solution of pH 12.5 was used, while percentage yield of 32P showed the maximum value, 54.3%, in the same conditions. Both anion and cation exchange resins were tried for the separation of 31Si and 32P from each other, and the cation exchange resin, Diaion SK-1 (ferric form), gave the most preferable results. 31Si and 32P separated by the procedure mentioned above were almost in a carrier-free form, and rediochemical purity of 31Si was 99.9% and that of 32P was nearly 100.0% Thus, we could prepare the radioactive 31Si and 32P in a high specific activity and in a high radiochemical purity by a simple procedure in a short while.