Fluorine-18 is a radioactive isotope of the element fluorine, commonly used in medical imaging, particularly in positron emission tomography (PET) scans. It has a half-life of about 110 minutes, which allows it to be used effectively in diagnostic procedures while minimizing radiation exposure to patients. This isotope is produced in cyclotrons and is often incorporated into radiopharmaceuticals that target specific biological processes. Its ability to emit positrons makes it valuable for visualizing metabolic activity in tissues, aiding in the diagnosis and monitoring of various conditions, including cancer and neurological disorders.