{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T16:26:33Z","timestamp":1775838393036,"version":"3.50.1"},"reference-count":15,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2015,7,16]],"date-time":"2015-07-16T00:00:00Z","timestamp":1437004800000},"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>In this article, we designed and studied silicon oxynitride (SiON) microring-based photonic structures for biosensing applications. We designed waveguides, directional couplers, and racetrack resonators in order to measure refractive index changes smaller than 10\u22126 refractive index units (RIU). We tested various samples with different SiON refractive indexes as well as the waveguide dimensions for selecting the sensor with the best performance. Propagation losses and bending losses have been measured on test structures, along with a complete characterization of the resonator\u2019s performances. Sensitivities and limit of detection (LOD) were also measured using glucose-water solutions and compared with expected results from simulations. Finally, we functionalized the resonator and performed sensing experiments with Aflatoxin M1 (AFM1). We were able to detect the binding of aflatoxin for concentrations as low as 12.5 nm. The results open up the path for designing cost-effective biosensors for a fast and reliable sensitive analysis of AFM1 in milk.<\/jats:p>","DOI":"10.3390\/s150717300","type":"journal-article","created":{"date-parts":[[2015,7,16]],"date-time":"2015-07-16T10:11:44Z","timestamp":1437041504000},"page":"17300-17312","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":51,"title":["Design and Optimization of SiON Ring Resonator-Based Biosensors for Aflatoxin M1 Detection"],"prefix":"10.3390","volume":"15","author":[{"given":"Romain","family":"Guider","sequence":"first","affiliation":[{"name":"Nanoscience Laboratory, Department of Physics, University of Trento, Via Sommarive 14,  Povo (TN) 38123, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Davide","family":"Gandolfi","sequence":"additional","affiliation":[{"name":"Nanoscience Laboratory, Department of Physics, University of Trento, Via Sommarive 14,  Povo (TN) 38123, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3207-9510","authenticated-orcid":false,"given":"Tatevik","family":"Chalyan","sequence":"additional","affiliation":[{"name":"Nanoscience Laboratory, Department of Physics, University of Trento, Via Sommarive 14,  Povo (TN) 38123, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7143-0540","authenticated-orcid":false,"given":"Laura","family":"Pasquardini","sequence":"additional","affiliation":[{"name":"LaBSSAH, Fondazione Bruno Kessler, Via Sommarive 18, Povo (TN) 38123, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alina","family":"Samusenko","sequence":"additional","affiliation":[{"name":"Nanoscience Laboratory, Department of Physics, University of Trento, Via Sommarive 14,  Povo (TN) 38123, Italy"},{"name":"Centre for Materials and Microsystems, Fondazione Bruno Kessler, Via Sommarive 18,  Povo (TN) 38123, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Georg","family":"Pucker","sequence":"additional","affiliation":[{"name":"Centre for Materials and Microsystems, Fondazione Bruno Kessler, Via Sommarive 18,  Povo (TN) 38123, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cecilia","family":"Pederzolli","sequence":"additional","affiliation":[{"name":"LaBSSAH, Fondazione Bruno Kessler, Via Sommarive 18, Povo (TN) 38123, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7316-6034","authenticated-orcid":false,"given":"Lorenzo","family":"Pavesi","sequence":"additional","affiliation":[{"name":"Nanoscience Laboratory, Department of Physics, University of Trento, Via Sommarive 14,  Povo (TN) 38123, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2015,7,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"51","DOI":"10.1016\/j.pquantelec.2013.02.001","article-title":"Label-free optical resonant sensors for biochemical applications","volume":"37","author":"Ciminelli","year":"2013","journal-title":"Prog. Quantum Electron."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"267","DOI":"10.1515\/nanoph-2012-0021","article-title":"Label-free detection with high-Q microcavities: A review of biosensing mechanisms for integrated devices","volume":"1","author":"Vollmer","year":"2012","journal-title":"Nanophotonics"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1002\/lpor.201100017","article-title":"Silicon microring resonators","volume":"6","author":"Bogaerts","year":"2012","journal-title":"Laser Photonics Rev."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"654","DOI":"10.1109\/JSTQE.2009.2032510","article-title":"Label-free biosensor arrays based on silicon ring resonators and high-speed optical scanning instrumentation","volume":"16","author":"Iqbal","year":"2010","journal-title":"IEEE J. Sel. Top. Quantum Electron."},{"key":"ref_5","unstructured":"Symphony Project Official Website. Available online: http:\/\/www.symphony-project.eu\/."},{"key":"ref_6","unstructured":"COMSOL Multiphysics Modeling Software. Available online: http:\/\/www.comsol.com."},{"key":"ref_7","unstructured":"Mancinelli, M. (2013). Linear and Nonlinear Coupling Effects in Sequence of Microresonators. [Ph.D. Thesis, University of Trento]."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"8724","DOI":"10.1364\/OE.21.008724","article-title":"Accurate determination of the quality factor and tunneling distance of axisymmetric resonators for biosensing applications","volume":"21","author":"Cheema","year":"2013","journal-title":"Opt. 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