Research Progress of Microfluidics in Radiopharmaceutical Quality Control

Radionuclide imaging is divided into positron emission tomography and single photon emission tomography and is widely used in clinical practice for diagnosis and treatment, as well as in clinical research for the development and evaluation of new therapies. Although it is a visually intuitive form of three‐dimensional functional imaging, this modality requires the injection of radiopharmaceuticals labeled with positron‐ or gamma‐emitting isotopes into patients to assess and quantify anabolism, gene expression, and other processes. For this reason, radiopharmaceuticals must undergo rigorous quality control (QC) to ensure product purity, efficacy, and safety. Traditional QC of pharmaceuticals is manual, requiring specially trained personnel, a range of expensive analytical and chemical equipment and laboratory space, the consumption of many samples, and usually a long time. Compared with ordinary pharmaceuticals, radiopharmaceuticals have the following unique characteristics: radioactivity, short lifetime, low synthesis yield, and high cost. Therefore, analytical methods and instrumentation must be exclusively developed for the QC of radiopharmaceuticals to avoid large losses owing to radioactive decay or handling. Microfluidics integrates microchannels or microchambers into several square centimeters of a microscale chip through micro–nanofabrication, allowing a precise manipulation of the fluid in microtubules, where various traditional physical, chemical, or biological experiments occur. Microfluidics is gaining attention in the field of analytical testing owing to significantly reduced consumption of samples and reagents, reduced analysis time, increased detection sensitivity, increased multiplexing, and reduced instrument size. Features such as micro size, micro volume, high sensitivity, and on‐line testing have led to increasing interest in microfluidics. This review covers the development of integrated microfluidic QC devices that can automatically process, test, analyze, and calculate completed test metrics online.