{"term":{"id":"14137","title":"fluorescence resonance energy transfer assay","longtitle":"IUPAC Gold Book - fluorescence resonance energy transfer assay","doi":"10.1351\/goldbook.14137","code":"14137","status":"current","initialism":"<em>initialism<\/em>: FRET","synonym":"<em>synonym<\/em>: FRET assay","definitions":[{"id":1,"text":"Assay based on the nonradiative energy transfer that occurs when the emission spectrum of a fluorescent donor molecule overlaps with the absorption spectrum of an energy acceptor molecule.","notes":{"1":"The donor and the acceptor fluorophores are linked directly or indirectly to two binding partners, and energy transfer occurs when the fluorophores are in close proximity with proper alignment of donor and acceptor electronic dipoles, i.e., when the binding partners interact.","2":"The fluorophores can be either of small molecule or protein nature.","3":"Use of a donor with a long fluorescence lifetime allows time-delayed (or time-resolved) fluorescence measurement (TR-FRET), providing conditions where other fluorophores in the assay medium are not detected."},"sources":["PAC, 2011, 83, 1129. 'Glossary of terms used in biomolecular screening (IUPAC Recommendations 2011)' on page 1141 (https:\/\/doi.org\/10.1351\/PAC-REC-09-05-03)"]}],"altoutputs":{"html":"https:\/\/goldbook.iupac.org\/terms\/view\/14137\/html","xml":"https:\/\/goldbook.iupac.org\/terms\/view\/14137\/xml","plain":"https:\/\/goldbook.iupac.org\/terms\/view\/14137\/plain"},"citation":"Citation: 'fluorescence resonance energy transfer assay' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351\/goldbook.14137","license":"The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/) for individual terms.","collection":"If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org .","disclaimer":"The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.","accessed":"2026-06-28T12:28:05+00:00"}}