Radiopharmaceuticals: Production, Physics, and Clinical Applications in Nuclear Medicine: A Short Review

Abstract

Introduction: The use of radioactive atoms in medicine is growing, particularly in nuclear medicine, where radiation is emitted from the body. Radiopharmaceuticals or radiotracers are artificial short-living radioisotopes labeled with special pharmaceuticals. There are around 1800 radioisotopes, but only around 200 are suitable for general applications. There are four methods for generating radioisotopes: reactor-producing, neutron activation, charged acceleration, and radioisotope generators. Cyclotrons are used to produce many other radioisotopes for medical applications. Physical and biomedical characteristics are crucial for radiopharmaceuticals for clinical use. Physical aspects include the type and energy of radiation, mother and daughter radioactive elements, purity, and half-life of radioactives. Biomedical considerations include easy adhesion to biomolecules, a dynamic time course in the body, toxicity, and high tissue targeting. Radiopharmaceuticals used in diagnosis differ from those used in therapy, with positron emission tomography (PET) using radioisotopes, and gamma-emitting radioisotope-labeled radiopharmaceuticals suitable for SPECT imaging. Over 90% of radiopharmaceuticals are used for diagnostic purposes. Conclusion: Nuclear medicine, as an inevitable part of modern medicine, follows different methods to create more effective diagnostic and therapeutic radiopharmaceuticals with respect to several physical and biological considerations.