Abstract:
:We have developed an all-electronic digital microfluidic device for microscale chemical synthesis in organic solvents, operated by electrowetting-on-dielectric (EWOD). As an example of the principles, we demonstrate the multistep synthesis of [(18)F]FDG, the most common radiotracer for positron emission tomography (PET), with high and reliable radio-fluorination efficiency of [(18)F]FTAG (88 ± 7%, n = 11) and quantitative hydrolysis to [(18)F]FDG (> 95%, n = 11). We furthermore show that batches of purified [(18)F]FDG can successfully be used for PET imaging in mice and that they pass typical quality control requirements for human use (including radiochemical purity, residual solvents, Kryptofix, chemical purity, and pH). We report statistical repeatability of the radiosynthesis rather than best-case results, demonstrating the robustness of the EWOD microfluidic platform. Exhibiting high compatibility with organic solvents and the ability to carry out sophisticated actuation and sensing of reaction droplets, EWOD is a unique platform for performing diverse microscale chemical syntheses in small volumes, including multistep processes with intermediate solvent-exchange steps.
journal_name
Proc Natl Acad Sci U S Aauthors
Keng PY,Chen S,Ding H,Sadeghi S,Shah GJ,Dooraghi A,Phelps ME,Satyamurthy N,Chatziioannou AF,Kim CJ,van Dam RMdoi
10.1073/pnas.1117566109subject
Has Abstractpub_date
2012-01-17 00:00:00pages
690-5issue
3eissn
0027-8424issn
1091-6490pii
1117566109journal_volume
109pub_type
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