{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,2]],"date-time":"2026-04-02T16:08:34Z","timestamp":1775146114284,"version":"3.50.1"},"reference-count":19,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2010,3,22]],"date-time":"2010-03-22T00:00:00Z","timestamp":1269216000000},"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>A refractive index sensor has been fabricated in silicon oxynitride by standard UV lithography and dry etching processes. The refractive index sensor consists of a 1D photonic crystal (PhC) embedded in a microfluidic channel addressed by fiber-terminated planar waveguides. Experimental demonstrations performed with several ethanol solutions ranging from a purity of 96.00% (n = 1.36356) to 95.04% (n = 1.36377) yielded a sensitivity (\u0394\u03bb\/\u0394n) of 836 nm\/RIU and a limit of detection (LOD) of 6 x 10-5 RIU, which is, however, still one order of magnitude higher than the theoretical lower limit of the limit of detection 1.3 x 10\u20136 RIU.<\/jats:p>","DOI":"10.3390\/s100302348","type":"journal-article","created":{"date-parts":[[2010,3,23]],"date-time":"2010-03-23T04:23:22Z","timestamp":1269318202000},"page":"2348-2358","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":57,"title":["Refractive Index Sensor Based on a 1D Photonic Crystal in a Microfluidic Channel"],"prefix":"10.3390","volume":"10","author":[{"given":"Pedro S.","family":"Nunes","sequence":"first","affiliation":[{"name":"Department of Micro and Nanotechnology, Technical University of Denmark, DTU Nanotech, Building 345 East, DK-2800 Kongens Lyngby, Denmark"}]},{"given":"Niels Asger","family":"Mortensen","sequence":"additional","affiliation":[{"name":"Department of Photonics Engineering, Technical University of Denmark, DTU Fotonik, Building 345 West, DK-2800 Kongens Lyngby, Denmark"}]},{"given":"J\u00f6rg P.","family":"Kutter","sequence":"additional","affiliation":[{"name":"Department of Micro and Nanotechnology, Technical University of Denmark, DTU Nanotech, Building 345 East, DK-2800 Kongens Lyngby, Denmark"}]},{"given":"Klaus B.","family":"Mogensen","sequence":"additional","affiliation":[{"name":"Department of Micro and Nanotechnology, Technical University of Denmark, DTU Nanotech, Building 345 East, DK-2800 Kongens Lyngby, Denmark"}]}],"member":"1968","published-online":{"date-parts":[[2010,3,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3498","DOI":"10.1002\/elps.200406108","article-title":"Recent developments in detection for microfluidic systems","volume":"25","author":"Mogensen","year":"2004","journal-title":"Electrophoresis"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1007\/s10404-007-0203-2","article-title":"Liquid-infiltrated photonic crystals: enhanced light-matter interactions for lab-on-a-chip applications","volume":"4","author":"Mortensen","year":"2008","journal-title":"Microfluid. Nanofluid"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"14376","DOI":"10.1364\/OE.15.014376","article-title":"Optical liquid ring resonator sensor","volume":"15","author":"Sumetsky","year":"2007","journal-title":"Opt. Express"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1063\/1.2219984","article-title":"Near ultraviolet-wavelength photonic-crystal biosensor with enhanced surface-to-bulk sensitivity ratio","volume":"89","author":"Ganesh","year":"2006","journal-title":"Appl. Phys. Lett"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"R93","DOI":"10.1088\/0957-0233\/17\/8\/R01","article-title":"Integrated optical sensors for the chemical domain","volume":"17","author":"Lambeck","year":"2006","journal-title":"Meas. Sci. Technol"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1623","DOI":"10.1364\/OL.33.001623","article-title":"Photonic crystal resonator integrated in a microfluidic system","volume":"33","author":"Nunes","year":"2008","journal-title":"Opt. Lett"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1511","DOI":"10.1039\/b818918h","article-title":"An array of ordered pillars with retentive properties for pressure-driven liquid chromatography fabricated directly from an unmodified cyclo olefin polymer","volume":"9","author":"Illa","year":"2009","journal-title":"Lab on a Chip"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1088\/0960-1317\/18\/5\/055021","article-title":"An electrochromatography chip with integrated waveguides for UV absorbance detection","volume":"18","author":"Gustafsson","year":"2008","journal-title":"J. Micromech. Microeng"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"5915","DOI":"10.1021\/ac070352p","article-title":"Pressure-driven reverse-phase liquid chromatography separations in ordered nonporous pillar array columns","volume":"79","author":"Eghbali","year":"2007","journal-title":"Anal. Chem"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1453","DOI":"10.1002\/jssc.200600468","article-title":"Pillar-structured microchannell's for on-chip liquid chromatography: Evaluation of the permeability and separation performance","volume":"30","author":"Desmet","year":"2007","journal-title":"J. Sep. Sci"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"3169","DOI":"10.1364\/OE.15.003169","article-title":"Photonic-crystal waveguide biosensor","volume":"15","author":"Skivesen","year":"2007","journal-title":"Opt. Express"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1093","DOI":"10.1364\/OL.29.001093","article-title":"Ultracompact biochemical sensor built with two-dimensional photonic crystal microcavity","volume":"29","author":"Chow","year":"2004","journal-title":"Opt. Lett"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1016\/j.snb.2009.06.007","article-title":"Photonic crystal microcavity sensor for ultracompact monitoring of reaction kinetics and protein concentration","volume":"141","author":"Zlatanovic","year":"2009","journal-title":"Sens. Actuator B-Chem"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"3284","DOI":"10.1364\/OL.32.003284","article-title":"Nanoscale microcavity sensor for single particle detection","volume":"32","author":"Lee","year":"2007","journal-title":"Opt. Lett"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"230","DOI":"10.1002\/1522-2683(200101)22:2<230::AID-ELPS230>3.0.CO;2-7","article-title":"Fabrication of quartz microchips with optical slit and development of a linear imaging UV detector for microchip electrophoresis systems","volume":"22","author":"Nakanishi","year":"2001","journal-title":"Electrophoresis"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"212","DOI":"10.1002\/jbio.200910010","article-title":"Chip scale integrated microresonator sensing systems","volume":"2","author":"Jokerst","year":"2009","journal-title":"J. Biophotonics"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1725","DOI":"10.1016\/j.optcom.2007.11.040","article-title":"Ultracompact refractive index sensor based on microcavity in the sandwiched photonic crystal waveguide structure","volume":"281","author":"Wang","year":"2008","journal-title":"Opt. Commun"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"3080","DOI":"10.1364\/OL.32.003080","article-title":"Slot-waveguide biochemical sensor","volume":"32","author":"Barrios","year":"2007","journal-title":"Opt. Lett"},{"key":"ref_19","unstructured":"Agilent Technologies Available online: http:\/\/www.chem.agilent.com\/en-us\/products\/instruments\/lc\/1200seriesrefractiveindexdetector\/pages\/default.aspx (accessed on 10 March 2010)."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/10\/3\/2348\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T22:01:50Z","timestamp":1760220110000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/10\/3\/2348"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2010,3,22]]},"references-count":19,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2010,3]]}},"alternative-id":["s100302348"],"URL":"https:\/\/doi.org\/10.3390\/s100302348","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2010,3,22]]}}}