Radiosynthesis of no-carrier-added meta -[ 124 I]iodobenzylguanidine for PET imaging of metastatic neuroblastoma

Meta -iodobenzylguanidine ( m IBG) has been radiolabelled at the no-carrier-added level with [ 124 I] for a proof of concept study to assess the diagnostic accuracy of [ 124 I] m IBG PET/CT in detecting metastatic deposits in patients diagnosed with metastatic neuroblastoma. Radiolabelling of m IBG was achieved via the iododesilylation reaction between [ 124 I]sodium iodide and meta -trimethylsilylbenzylguanidine. [ 124 I] m IBG was produced in 62–70 % radioiodide incorporation yield from [ 124 I]sodium iodide. The average amount of formulated [ 124 I] m IBG was 359 MBq (range 344–389 MBq) with an average specific radioactivity of 4.1 TBq μmol −1 (range 1.8–5.9 TBq μmol −1 ) at end of synthesis.