Production Method for Cobalt-58 (58Co) Radioisotopes By 58Ni(n,p)58Co Reaction

Radioisotope 58Co is one of the radioisotope which is developed for the preparation of labelled compounds. Radioisotope 58Co has a gamma radiation energy which is suitable for the radiotracer technique purpose. Radioisotope 58Co can be produced through neutron activation reaction 58Ni(n,p)58Co in a nuclear reactor by irradiation the NiO target. In this study the target used is from natural origin which has a natural isotopic abundance (θ) of 67.88% and a cross section (σ)nf of 0.09 barn. The establishment of the production method for 58Co was the aim of this study, and the result was expected could be used for further development of the labelled compound production. The NiO target was irradiated in nuclear reactor TRIGA 2000 Bandung by a neutron flux of 6.387 x 1013 n / cm2 / s1 for 60 hour. The irradiated target dissolved in HCl 12 M further more evaporated until dry and dissolved in HCl 9 M. The separation of 58Co radioisotope from the impurities used an anion exchange method using Dowex resin with the eluent HCl 4 M. The final 58Co radioisotope product was a clear colorless solution of 58CoCl2 with p H 1 - 1.5 and the average radioactivity concentration of 0.085 mCi/m L. The radionuclide purity of 58Co was determined by using multichannel analyzer (MCA). Gamma ray spectrum appeared at energy of 810.69 keV, 863.95 keV, 1675.40 keV indicating there was radioisotope 58Co as the result of 58Ni(n,p)58Co reaction. The radiochemical purity determination was done by paper chromatographic method using 3 M M Whatman as the stationary phase and the mixture of NH3 : ethanol : water (1:10:20) as mobile phase, It was found the migration of 58CoCl2 gave an Rf value of zero (Rf = 0) and a radiochemical purity > 99% and the solution still stable in one week. The nickel metal determination was done by spectrophotometry method using dimethylglyoxime reagents, indicated that the concentration on nickel metal was not exceed 2 ppm. (author)