Radiosynthesis and preliminary biodistribution in mice of 6‐deoxy‐6‐[131I]iodo‐ L ‐ascorbic acid

An ascorbate analog labeled with iodine‐131, 6‐deoxy‐ 6‐[131I]iodo‐L‐ascorbic acid was prepared for evaluation as an in vivo tracer of L‐ascorbic acid. The no‐carrier‐added radiosynthesis was conducted by nucleophilic bromine–iodine exchange between the brominated precursor and sodium [131I]iodide in 2‐pentanone at 130–140°C. HPLC purification using a reverse‐phase column gave 6‐deoxy‐6‐[131I]iodo‐L‐ascorbic acid in radiochemical yield of 36–60% with high radiochemical purity and satisfactory‐specific radioactivity in a total preparation time of 90 min. Biodistribution studies in fibrosarcoma‐bearing mice showed a high uptake in the adrenal glands, accompanied by low activity of tumor accumulation, accumulation properties similar to previous results obtained with 14C‐labeled ascorbic acid and 6‐deoxy‐6‐[18F]fluoro‐L‐ascorbic acid, in spite of high level of deiodination.