UCLA

There is currently a need to improve production of radiotracers for positron emission tomography (PET) imaging because although thousands of radiotracers have been developed in research settings, only a few are readily available, severely limiting the biological problems that can be studied in vivo via PET. An electrowetting-on-dielectric (EWOD) digital microfluidic chip was designed with multifunctional electrodes (for heating, temperature sensing, and EWOD driving) to synthesize a variety of ¹⁸F-labeled tracers targeting a range of biological processes. A single EWOD radiosynthesizer device design was used for complete synthesis of four radiotracers (a sugar, a DNA nucleoside, a protein-labelling compound, and a neurotransmitter). All of the key synthesis steps for radiochemistry have been demonstrated on chip: concentration of fluoride ion, solvent exchange, chemical reaction, and purification. A mirrored configuration of valve metal oxide was also investigated for use as a cost effective and high electrical performance dielectric in EWOD.