Microreactors for radiopharmaceutical synthesis

Multiple advantages of microfluidics have been demonstrated in the area of organic synthesis. However, only a limited number of them have found applications in radiopharmaceutical synthesis, while that is an area where the need for improvements offered by microfluidics is very significant. The need is to create an environment where all reactions involving short-lived radioisotopes such as ¹⁸F (110 min half-life) or ¹¹C (20 min half-life) are rapid and high-yielding while the devices are controlled remotely. Several groups have identified the potential of microfluidics in this area and have demonstrated that various steps of conventional radiosynthesis can be replaced by microfluidic devices. However, despite promising results that stir up the interest in the scientific community, none of these inventions has found commercial applications with broad use yet. This article will review the technologies reported to date and analyze the unmet needs that will have to be addressed before microfluidic technology has a chance of becoming a viable and truly advantageous method of preparation of commercial radiopharmaceuticals. The latter mostly center around Positron Emission Tomography (PET) biomarkers.