Isotopes are used to sterilize medical equipment and perform diagnostic imaging scans and radiopharmaceutical evaluations and treatments in medical settings. They are also used in making smoke detectors, detectors that protect against nuclear terrorism and control rods for nuclear power reactors.
In nuclear medicine, short-lived isotopes are used as radioactive tracers that patients receive orally via inhalation or injection. The tracers emit gamma rays from a target area in a patient's body, allowing specialized machines to produce images for review by a physician. Positron emission tomography, or PET, scans are an example of radioisotopes used in nuclear medicine for diagnostic purposes. The isotopes used in PET scans are produced in a device called a cyclotron. This type of scan is useful for producing images of the brain and cardiac structures, as well as for detecting many types of cancer.
Isotopes are atoms of a single element that differ in their numbers of neutrons. For example, the element hydrogen exists in nature as the isotopes hydrogen, deuterium and tritium. The hydrogen isotope is the most abundant type on Earth and possesses zero neutrons per atom, whereas a deuterium atom contains one neutron, and a tritium atom has two. It can be expensive and take a lot of time to produce pure samples of isotopes, making it difficult for scientists to keep up with the demand for isotopes used in real-world applications.