Separation of pertechnetate from molybdate by anion-exchange chromatography:: Recovery of 99mTc from (n, y)99Mo and suitability for use in central radiopharmacy (CRPh)

A novel method for the recovery of (TcO4-)-Tc-99m from (n , gamma)(99) Mo using conventional anion-exchange chromatography over Dowex- 1 x 8 column, followed by elution and subsequent novel purification over AgCl-alumina column is reported. (MoO42-)-Mo-99 2- solution (7-14GBq/mg) in NaOH was passed down a Dowex- 1 x 8 column (6-7 x 2 min), collected and preserved for reuse on the subsequent days. (TcO4-)-Tc-99m preferentially retained on the Dowex-1 column, was recovered quantitatively by elution with 4 nil of 4 M HNO3\ or 4 ml 0.2 M HClO4 or 6 ml of 0.2 M NaI solution. Further purification to deliver 99mTcO(4)(-) in a physiological vehicle has been achieved. Use of NaI eluent and post elution purification over a bed of 1 g AgCl + 1 g alumina developed has been adapted in preference to the other two eluents. The overall yield of (TCO4-)-T-99m was 75%-85% and the quality features of (TcO4-)-Tc-99m were compatible to radiopharmaceutical use. The method has applicability for decontamination of 99(g)Tc from spent 99Mo waste solution and recovery of Tc-99g for research use. The procedure should also be equally applicable for recovery of (188) ReO4- from 188WO(4)(2-) in a radioisotope laboratory.