{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,7]],"date-time":"2026-06-07T14:45:42Z","timestamp":1780843542819,"version":"3.54.1"},"reference-count":41,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2017,4,3]],"date-time":"2017-04-03T00:00:00Z","timestamp":1491177600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>MicroRNAs (miRNAs) act as biomarkers for the diagnosis of a variety of cancers. Since the currently used methods for miRNA detection have limitations, simple, sensitive, and cost-effective methods for the detection of miRNA are required. This work demonstrates a facile, quencher-free, fluorescence-based analytical method for cost-effective and sensitive detection of miRNA using a super 2-aminopurine (2-AP)-labeled hairpin probe (HP) and exonuclease I activity. Specifically, the fluorescence of 2-AP is strongly quenched when it is incorporated within DNA. In the presence of a target miRNA, HP attains an open conformation by hybridizing with the target miRNA to form a double-stranded structure with a protruding 3\u2032-terminus. Next, the digestion of the protruding 3\u2032-terminus is triggered by exonuclease I, during which 2-AP is released free in solution from the DNA, thereby increasing fluorescence. This method is highly sensitive, with a detection limit of 0.5 nM\u201410 times lower than a previously reported quencher-free fluorescence method. Furthermore, this method has potential applications in clinical diagnosis and biomedical research.<\/jats:p>","DOI":"10.3390\/s17040760","type":"journal-article","created":{"date-parts":[[2017,4,3]],"date-time":"2017-04-03T13:32:30Z","timestamp":1491226350000},"page":"760","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["An Exonuclease I-Based Quencher-Free Fluorescent Method Using DNA Hairpin Probes for Rapid Detection of MicroRNA"],"prefix":"10.3390","volume":"17","author":[{"given":"Changbei","family":"Ma","sequence":"first","affiliation":[{"name":"State Key Laboratory of Medical Genetics & School of Life Sciences, Central South University, Changsha 410013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haisheng","family":"Liu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Medical Genetics & School of Life Sciences, Central South University, Changsha 410013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kefeng","family":"Wu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Medical Genetics & School of Life Sciences, Central South University, Changsha 410013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mingjian","family":"Chen","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Medical Genetics & School of Life Sciences, Central South University, Changsha 410013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liyang","family":"Zheng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Medical Genetics & School of Life Sciences, Central South University, Changsha 410013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jun","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Medical Genetics & School of Life Sciences, Central South University, Changsha 410013, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,4,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"506","DOI":"10.1039\/C3CS60312A","article-title":"MicroRNAs as novel biological targets for detection and regulation","volume":"43","author":"Li","year":"2014","journal-title":"Chem. 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