Editing Radioactive tracer (section)

{{Short description|Chemical compound}}
[[File:HD.6D.758 (13471503475).jpg|thumb|Illustration showing the use of [[Beta-decay|beta-decaying]] [[carbon-14]] as a radioactive tracer in a plant.]]
A '''radioactive tracer''', '''radiotracer''', or '''radioactive label''' is a [[Synthetic element|synthetic]] derivative of a [[natural compound]] in which one or more atoms have been replaced by a [[radionuclide]] (a radioactive atom). By virtue of its [[radioactive decay]], it can be used to explore the mechanism of chemical reactions by tracing the path that the radioisotope follows from reactants to products. '''Radiolabeling''' or '''radiotracing''' is thus the radioactive form of [[isotopic labeling]]. In biological contexts, experiments that use radioisotope tracers are sometimes called '''radioisotope feeding''' experiments.

Radioisotopes of [[hydrogen]], [[carbon]], [[phosphorus]], [[sulfur]], and [[iodine]] have been used extensively to trace the path of [[biochemistry|biochemical reactions]]. A radioactive tracer can also be used to track the distribution of a substance within a natural system such as a [[cell (biology)|cell]] or [[tissue (biology)|tissue]],<ref name=rennie-99>{{cite journal | vauthors = Rennie MJ | title = An introduction to the use of tracers in nutrition and metabolism | journal = The Proceedings of the Nutrition Society | volume = 58 | issue = 4 | pages = 935–44 | date = November 1999 | pmid = 10817161 | doi = 10.1017/S002966519900124X | doi-access = free }}</ref> or as a [[flow tracer]] to track [[fluid dynamics|fluid flow]]. Radioactive tracers are also used to determine the location of fractures created by [[hydraulic fracturing]] in natural gas production.<ref name="Reis_iodine">Reis, John C. (1976). ''Environmental Control in Petroleum Engineering.'' Gulf Professional Publishers.</ref> Radioactive tracers form the basis of a variety of imaging systems, such as, [[PET scan]]s, [[SPECT scan]]s and [[Technetium-99m|technetium scan]]s. [[Radiocarbon dating]] uses the naturally occurring [[carbon-14]] isotope as an [[isotopic label]].

In radiopharmaceutical sciences some misuse of established scientific terms exist. Therefore an international "Working Group on Nomenclature in Radiopharmaceutical Chemistry and Related Areas" was formed in 2015 by the Society of Radiopharmaceutical Sciences (SRS). Their goal was to clarify terminology and to establish a standardized nomenclature through global consensus, ensuring consistency and accuracy within the discipline.<ref>{{Cite journal |last=Coenen |first=Heinz H. |last2=Gee |first2=Antony D. |last3=Adam |first3=Michael |last4=Antoni |first4=Gunnar |last5=Cutler |first5=Cathy S. |last6=Fujibayashi |first6=Yasuhisa |last7=Jeong |first7=Jae Min |last8=Mach |first8=Robert H. |last9=Mindt |first9=Thomas L. |last10=Pike |first10=Victor W. |last11=Windhorst |first11=Albert D. |date=2017-12-01 |title=Consensus nomenclature rules for radiopharmaceutical chemistry — Setting the record straight |url=https://linkinghub.elsevier.com/retrieve/pii/S0969805117303189 |journal=Nuclear Medicine and Biology |volume=55 |pages=v–xi |doi=10.1016/j.nucmedbio.2017.09.004 |issn=0969-8051}}</ref>