Radiopharmaceuticals and Methods of Radiolabeling

Abstract

A radiopharmaceutical is a radioactive compound used for the diagnosis and therapeutic treatment of human diseases. In nuclear medicine nearly 95{\%} of the radiopharmaceuticals are used for diagnostic purposes, while the rest are used for therapeutic treatment. Radiopharmaceuticals usually have no pharmacologic effect, because in most cases they are used in tracer quantities. In these cases, they do not show any dose-response relationship and thus differ from conventional drugs. Because they are administered to humans, they should be sterile and pyrogen free, and they should undergo all quality control measures required of a conventional drug. A radiopharmaceutical may be a radioactive element such as 133Xe, or a labeled compound such as 131I-iodinated proteins and 99mTc-labeled compounds.