A route for the preparation of [P-32]-sodium monofluorophosphate

[P-32]-labelled sodium monofluorophosphate (Na2FPO3) was prepared according to a procedure, which is based on melting of a mixture of carrier-added [P -32]-phosphoric acid and ammonium bifluoride, both solid. Monofluorophospha te was precipitated as the silver salt from the reaction mixture, then it w as converted to the sodium salt by using a cation exchange column in Na+ fo rm. The influence of the molar ratios of the reactants, and the reaction ti me on the final yield was studied. Powder X-ray diffraction showed a chemic al purity of about 98 % and absence of NaF in the final product. After a re action time of 2 hours and a molar ratio of the reactants of 1:1, the yield for the reaction was 30 % of the initial P-32 activity, corresponding to a specific activity of 56 MBq P-32 per mmol. An increase in yield is possibl e by increasing the reaction time, a higher specific activity may be obtain ed by a decrease of carrier phosphoric acid. The advantages of the procedur e developed are the availability of [P-32]-phosphoric acid, and the simple preparation of the compound.