{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T03:42:54Z","timestamp":1779334974592,"version":"3.51.4"},"reference-count":38,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2011,10,11]],"date-time":"2011-10-11T00:00:00Z","timestamp":1318291200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We combine suspended-core microstructured optical fibers with the photoinduced electron transfer (PET) effect to demonstrate a new type of fluorescent optical fiber-dip sensing platform for small volume ion detection. A sensor design based on a simple model PET-fluoroionophore system and small core microstructured optical fiber capable of detecting sodium ions is demonstrated. The performance of the dip sensor operating in a high sodium concentration regime (925 ppm Na+) and for lower sodium concentration environments (18.4 ppm Na+) is explored and future approaches to improving the sensor\u2019s signal stability, sensitivity and selectivity are discussed.<\/jats:p>","DOI":"10.3390\/s111009560","type":"journal-article","created":{"date-parts":[[2011,10,11]],"date-time":"2011-10-11T12:52:32Z","timestamp":1318337552000},"page":"9560-9572","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Photoinduced Electron Transfer Based Ion Sensing within an Optical Fiber"],"prefix":"10.3390","volume":"11","author":[{"given":"Florian V.","family":"Englich","sequence":"first","affiliation":[{"name":"Institute for Photonics & Advanced Sensing (IPAS) and School of Chemistry & Physics, The University of Adelaide, North Terrace, SA 5005, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tze Cheung","family":"Foo","sequence":"additional","affiliation":[{"name":"Institute for Photonics & Advanced Sensing (IPAS) and School of Chemistry & Physics, The University of Adelaide, North Terrace, SA 5005, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andrew C.","family":"Richardson","sequence":"additional","affiliation":[{"name":"Institute for Photonics & Advanced Sensing (IPAS) and School of Chemistry & Physics, The University of Adelaide, North Terrace, SA 5005, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Heike","family":"Ebendorff-Heidepriem","sequence":"additional","affiliation":[{"name":"Institute for Photonics & Advanced Sensing (IPAS) and School of Chemistry & Physics, The University of Adelaide, North Terrace, SA 5005, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christopher J.","family":"Sumby","sequence":"additional","affiliation":[{"name":"Institute for Photonics & Advanced Sensing (IPAS) and School of Chemistry & Physics, The University of Adelaide, North Terrace, SA 5005, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tanya M.","family":"Monro","sequence":"additional","affiliation":[{"name":"Institute for Photonics & Advanced Sensing (IPAS) and School of Chemistry & Physics, The University of Adelaide, North Terrace, SA 5005, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2011,10,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"17891","DOI":"10.1364\/OE.15.017891","article-title":"Enhancement of Fluorescence-Based Sensing Using Microstructured Optical Fibers","volume":"15","author":"Afshar","year":"2007","journal-title":"Opt. 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