6-Deoxy-6-[
18F]fluoro-L-threo-2,3-hexodiulosonic acid γ-lactone(6-[
18F]fluoro-dehydroascorbic acid,
18F-FDHA)was synthesized by oxidation of 6-deoxy-6-[
18F]fluoro-L-ascorbic acid(
18F-DFA)with Br
2, a route that is analogous to the original synthesis of FDHA, in order to develop a radiotracer for nuclear medical imaging. Tissue biodistribution of
18F-FDHA in fibrosarcoma-bearing mice showed a low accumulation of radioactivity in the brain, with both substantial in vivo defluorination and low tumoral uptake levels. Several organs of mice unfed for 24h showed a more significant increase in radioactivity postinjection of
18F-FDHA than did fed mice. Co-injection with 2-deoxyglucose of
18F-FDHA did not significantly alter brain and tumor uptake, as confirmed by tissue-to-blood ratios, and as compared to control experiments. Thus,
18F-FDHA does not exhibit desirable properties as a brain-targeting imaging agent for ascorbic acid bioactivity.
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