{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:01:10Z","timestamp":1760241670867,"version":"build-2065373602"},"reference-count":26,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2018,7,14]],"date-time":"2018-07-14T00:00:00Z","timestamp":1531526400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Ministry of Science, ICT &amp;Future Planning (MISP) of Korea","award":["H-GUARD_2013M3A6B2078"],"award-info":[{"award-number":["H-GUARD_2013M3A6B2078"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A disposable potentiometric sensor was newly developed for the amplification-coupled detection of nucleic acids. The hydrogen-ion is generally released during isothermal amplification of nucleic acids. The surface potential on the oxide-functionalized electrode of the extended gate was directly measured using full electrical circuits with the commercial metal-oxide semiconductor field-effect transistors (MOSFETs) and ring oscillator components, which resulted in cost-effective, portable and scalable real-time nucleic acid analysis. The current-starved ring oscillator changes surface potential to its frequency depending on the square of the variation in pH with a high signal-to-noise ratio during isothermal amplification. The device achieves a conversion rate of 20.5 kHz\/mV and a detection resolution of 200 \u00b5V for the surface potential. It is demonstrated that the sensor successfully monitors in real-time isothermal amplification of the extracted nucleic acids from Salmonella pathogenic bacteria. The in situ variations in the frequency of the pH-sensitive sensor were compared with the results of both a conventional optical device and pH-meter during isothermal amplification.<\/jats:p>","DOI":"10.3390\/s18072277","type":"journal-article","created":{"date-parts":[[2018,7,16]],"date-time":"2018-07-16T04:05:33Z","timestamp":1531713933000},"page":"2277","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["A Sensitive Potentiometric Sensor for Isothermal Amplification-Coupled Detection of Nucleic Acids"],"prefix":"10.3390","volume":"18","author":[{"given":"Kang-Ho","family":"Lee","sequence":"first","affiliation":[{"name":"Daegu Research Center for Medical Devices, Korea Institute of Machinery and Materials, Daegu 42994, Korea"}]},{"given":"Dongkyu","family":"Lee","sequence":"additional","affiliation":[{"name":"Daegu Research Center for Medical Devices, Korea Institute of Machinery and Materials, Daegu 42994, Korea"}]},{"given":"Jongsu","family":"Yoon","sequence":"additional","affiliation":[{"name":"Daegu Research Center for Medical Devices, Korea Institute of Machinery and Materials, Daegu 42994, Korea"}]},{"given":"Ohwon","family":"Kwon","sequence":"additional","affiliation":[{"name":"Daegu Research Center for Medical Devices, Korea Institute of Machinery and Materials, Daegu 42994, Korea"}]},{"given":"Jaejong","family":"Lee","sequence":"additional","affiliation":[{"name":"Nano-Mechanical Systems, Korea Institute of Machinery and Materials, Daejeon 34103, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2018,7,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"441","DOI":"10.1016\/0022-2836(75)90213-2","article-title":"A rapid method for determining sequences in DNA by primed synthesis with DNA polymerase","volume":"94","author":"Sanger","year":"1975","journal-title":"J. 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