A microfluidic radiopharmaceutical production system and process for synthesizing per run approximately, but not less than, one (1) unit dose of a radiopharmaceutical biomarker for use in positron emission tomography (PET). The radiopharmaceutical production system includes a reaction vessel that receives a radioisotope from an accelerator or other radioisotope generator. Organic and aqueous reagents are introduced into the reaction vessel, and the mixture is heated to synthesize a solution of a pre-selected radiopharmaceutical. The radiopharmaceutical solution is purified by passing the solution through a solid phase extraction column and a filter. The synthesis process produces per run a quantity of radiopharmaceutical approximately equal to, but not less than, one (1) unit dose of a radiopharmaceutical, reducing waste and allowing for the production of radiopharmaceutical on an as-needed basis. The synthesis process allows for the production of biomarker radiopharmaceuticals on site and close to the location where the unit dose will be administered to the patient. On-site, as-needed production of radiopharmaceuticals in small doses reduces the time between the synthesis of the radiopharmaceutical and the administration of that radiopharmaceutical, thereby minimizing the loss of active isotopes through decay and allowing the production of lesser amounts of radioisotopes overall.