Radiochemical quality control of the radiopharmaceutical, 89SrCl2 produced in FBTR

Abstract

89SrCl2 radiopharmaceuticals is mainly used for bone pain palliation in the cancer patients, is being produced in FBTR via 89Y(n, p)89Sr using yttria target. The irradiated yttria target is chemically processed in high pure quartz distilled nitric acid medium in hot cell facility, to avoid the corrosion of components of hotcell due to chloride ions while using HCl medium. Being ionic species, the purified 89Sr(II) cation in aqueous solution containing bulk nitrate and other trace anions, exists as SrXn species where X: F−, Cl−, Br−, NO3−, PO43− and SO42−, n: stoichiometric anion content. The aim of the manuscript is to standardise an efficient ultra-low level anion purification method (ppb range) for the conversion of SrXn to SrCl2 and estimate the residual anionic impurities as recommended by the appropriate source specifications for its medical application. Various methods were standardised for the removal of anions in the SrCl2 source produced by the above process which include evaporation, calcination, anion exchange column, cation exchange column as well as its combination with pre-concentration column of ion chromatography (IC) technique using 89Sr tracers as well as FBTR produced 89Sr solution. Assay of 89Sr and other anions including nitrate for the above study were accomplished using Cerenkov counting and ion chromatography respectively. Thus evaporation-calcination-column chromatography mode was finalised to obtain pure SrCl2 source free from nitrate and other anionic impurities. This is the first ever systematic study for the Radiochemical quality control of nca 89SrCl2 radiopharmaceutical produced in a fast reactor. This study also finds its application to any analytical lab as well as industry where there is a requirement of anion purification in the ppb level.