{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,17]],"date-time":"2025-10-17T14:10:01Z","timestamp":1760710201183,"version":"build-2065373602"},"reference-count":49,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2020,4,22]],"date-time":"2020-04-22T00:00:00Z","timestamp":1587513600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100011033","name":"Agencia Estatal de Investigaci\u00f3n","doi-asserted-by":"publisher","award":["TEC2016-79367-C2-2-R project"],"award-info":[{"award-number":["TEC2016-79367-C2-2-R project"]}],"id":[{"id":"10.13039\/501100011033","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003329","name":"Ministerio de Econom\u00eda y Competitividad","doi-asserted-by":"publisher","award":["TEC2016-79367-C2-2-R project"],"award-info":[{"award-number":["TEC2016-79367-C2-2-R project"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A fluorescent optical fiber sensor for the detection of mercury (Hg2+) ions in aqueous solutions is presented in this work. The sensor was based on a fluorophore-labeled thymine (T)-rich oligodeoxyribonucleotide (ON) sequence that was directly immobilized onto the tip of a tapered optical fiber. In the presence of mercury ions, the formation of T\u2013Hg2+-T mismatches quenches the fluorescence emission by the labeled fluorophore, which enables the measurement of Hg2+ ions in aqueous solutions. Thus, in contrast to commonly designed sensors, neither a fluorescence quencher nor a complementary ON sequence is required. The sensor presented a response time of 24.8 seconds toward 5 \u00d7 10\u221212 M Hg2+. It also showed both good reversibility (higher than the 95.8%) and selectivity: the I0\/I variation was 10 times higher for Hg2+ ions than for Mn2+ ions. Other contaminants examined (Co2+, Ag+, Cd2+, Ni2+, Ca2+, Pb2+, Mn2+, Zn2+, Fe3+, and Cu2+) presented an even lower interference. The limit of detection of the sensor was 4.73 \u00d7 10\u221213 M Hg2+ in buffer solution and 9.03 \u00d7 10\u221213 M Hg2+ in ultrapure water, and was also able to detect 5 \u00d7 10\u221212 M Hg2+ in tap water.<\/jats:p>","DOI":"10.3390\/s20082372","type":"journal-article","created":{"date-parts":[[2020,4,23]],"date-time":"2020-04-23T02:10:52Z","timestamp":1587607852000},"page":"2372","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["Development of an Aptamer Based Luminescent Optical Fiber Sensor for the Continuous Monitoring of Hg2+ in Aqueous Media"],"prefix":"10.3390","volume":"20","author":[{"given":"Nerea","family":"De Acha","sequence":"first","affiliation":[{"name":"Department of Electrical, Electronic and Communications Engineering, Public University of Navarra, Ed. Los Tejos, Campus Arrosad\u00eda s\/n, E-31006 Pamplona, Navarra, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5219-989X","authenticated-orcid":false,"given":"C\u00e9sar","family":"Elos\u00faa","sequence":"additional","affiliation":[{"name":"Department of Electrical, Electronic and Communications Engineering, Public University of Navarra, Ed. Los Tejos, Campus Arrosad\u00eda s\/n, E-31006 Pamplona, Navarra, Spain"},{"name":"Institute of Smart Cities, Public University of Navarra, Ed. Jer\u00f3nimo de Ayanz, Campus Arrosad\u00eda s\/n, E-31006 Pamplona, Navarra, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3311-0834","authenticated-orcid":false,"given":"Francisco J.","family":"Arregui","sequence":"additional","affiliation":[{"name":"Department of Electrical, Electronic and Communications Engineering, Public University of Navarra, Ed. Los Tejos, Campus Arrosad\u00eda s\/n, E-31006 Pamplona, Navarra, Spain"},{"name":"Institute of Smart Cities, Public University of Navarra, Ed. Jer\u00f3nimo de Ayanz, Campus Arrosad\u00eda s\/n, E-31006 Pamplona, Navarra, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2020,4,22]]},"reference":[{"key":"ref_1","unstructured":"WHO (2019, October 22). Drinking-Water. World Health Organization Fact Sheets. 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