PRODUCTION OF ⁸⁹SR USING (n,γ)- AND (n,p) REACTIONS

Abstract

Two technologies of 89 Sr production: "traditional", based on 88 Sr(n,y)-reaction, and alternative, based on 89 Y(n,p) reaction, has been discussed in the paper. The quality and suitability for radiopharmaceuticals production of two types of product (with carrier and no-carrier-added) are discussed.For more then 20 years strontium-89 is used for palliative treatment of bone metastases. Several years ago -Metastron -strontium chloride solution produced by Amersham was approved for clinical use.Two ways of strontium-89 production are known. First is «traditional» one, based on 88 Sr(n,y) 89 Sr reaction, taking place in thermal neutron fluxes. The second way is an alternative, based on 89 Y(n,p) 89 Sr reaction, occurring in fast neutron fluxes. In both cases production of strontium-89 is accompanied by radioactive impurities production, particularly -strontium-85 and strontium-90, effecting final product quality.Regardless of production technology, strontium-89 preparation should confirm a number of requirements, conditioned by its application as radiopharmatheutical. Its specific activity should be not less then 100 mCi/g, gamma-emitting impurities content should be not greater then 0,4%, strontium-90 impurity content should be not higher then 2 10" 4 %.Basic elements of technology flow-sheets, using both production ways, designed and applied by RIAR for strontium-89 production, are discussed in the report.

Determination of radionuclide impurities in pure beta radiation sources by semiconductor spectrometry

“…Both methods of spectra deconvolution described above in Sections 2.2 and 2.3 were tested on data from the measurement of samples with varying amounts of 89 Sr and 90 Sr. This mixture is commonly formed during the production of 89 Sr radionuclide due to parasitic reactions [7]. The samples also contained 90 Y, which is a radioactive decay product of 90 Sr. As the parent nuclide has a much longer half-life than the daughter nuclide 2 , it can be assumed that secular (long-term) radioactive equilibrium between these nuclides was established in the sample.…”

Separation of strontium from yttrium nitrate solutions by solvent extraction with dicyclohexano-18-crown-6

“…Comparison of the extraction process and the existing one, based on the precipitation of yttrium hydroxide [1], shows Brought to you by | New York University Bobst Library Technical Services Authenticated Download Date | 6/1/15 2:17 PM the advantages of the first one. In the precipitation process, the volume of the processing solution for the 100 g yttrium oxide target reaches 2-2.5 L (as the yttrium concentration should not exceed 45-50 g/L), whereas the extraction process allows one to work at a 150-170 g/L concentration, decreasing the processing volume to 0.5-0.6 L. After yttrium hydroxide precipitation, strontium has to be isolated from a large volume of solution with high salinity (3-4 L of 2-4 M ammonia nitrate solution), and this is a distinct problem.…”

“…89 Sr via the 89 Y(n, p) reaction. Despite low yieldsirradiation of yttrium oxide in a fast neutron flux of 10 15 cm −2 s −1 for 40-50 days gives 10-12 mCi of 89 Sr per gram of Y 2 O 3 [1] -there is an interest in this reaction, as it provides the production of high-specific activity 89 Sr (of "no carrier added" grade) with a low content of inseparable radioactive impurity 90 Sr. These characteristics are of great importance for the final product used in modern nuclear medicine for bone metastases palliation treatment.…”

“…In turn, the proper technology should be applied for 89 Sr isolation from the irradiated target. A previously described process of 89 Sr production [1] was based on the precipitation of yttrium hydroxide or oxalate followed by chromatographic purification. This process is too bulky and laborious for remote operation, and it can hardly be used for reprocessing *Author for correspondence (E-mail: rostik@nanum.kaeri.re.kr).…”