{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T10:02:02Z","timestamp":1771063322150,"version":"3.50.1"},"reference-count":40,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,2,2]],"date-time":"2023-02-02T00:00:00Z","timestamp":1675296000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/50014\/2020"],"award-info":[{"award-number":["UIDB\/50014\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BD\/130674\/2017"],"award-info":[{"award-number":["SFRH\/BD\/130674\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BD\/ 146784\/2019"],"award-info":[{"award-number":["SFRH\/BD\/ 146784\/2019"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["CEECIND\/00471\/2017"],"award-info":[{"award-number":["CEECIND\/00471\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["GRC ED431C 2020\/09"],"award-info":[{"award-number":["GRC ED431C 2020\/09"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010801","name":"Xunta de Galicia","doi-asserted-by":"publisher","award":["UIDB\/50014\/2020"],"award-info":[{"award-number":["UIDB\/50014\/2020"]}],"id":[{"id":"10.13039\/501100010801","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010801","name":"Xunta de Galicia","doi-asserted-by":"publisher","award":["SFRH\/BD\/130674\/2017"],"award-info":[{"award-number":["SFRH\/BD\/130674\/2017"]}],"id":[{"id":"10.13039\/501100010801","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010801","name":"Xunta de Galicia","doi-asserted-by":"publisher","award":["SFRH\/BD\/ 146784\/2019"],"award-info":[{"award-number":["SFRH\/BD\/ 146784\/2019"]}],"id":[{"id":"10.13039\/501100010801","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010801","name":"Xunta de Galicia","doi-asserted-by":"publisher","award":["CEECIND\/00471\/2017"],"award-info":[{"award-number":["CEECIND\/00471\/2017"]}],"id":[{"id":"10.13039\/501100010801","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010801","name":"Xunta de Galicia","doi-asserted-by":"publisher","award":["GRC ED431C 2020\/09"],"award-info":[{"award-number":["GRC ED431C 2020\/09"]}],"id":[{"id":"10.13039\/501100010801","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Biochemical\u2013chemical sensing with plasmonic sensors is widely performed by tracking the responses of surface plasmonic resonance peaks to changes in the medium. Interestingly, consistent sensitivity and resolution improvements have been demonstrated for gold nanoparticles by analyzing other spectral features, such as spectral inflection points or peak curvatures. Nevertheless, such studies were only conducted on planar platforms and were restricted to gold nanoparticles. In this work, such methodologies are explored and expanded to plasmonic optical fibers. Thus, we study\u2014experimentally and theoretically\u2014the optical responses of optical fiber-doped gold or silver nanospheres and optical fibers coated with continuous gold or silver thin films. Both experimental and numerical results are analyzed with differentiation methods, using total variation regularization to effectively minimize noise amplification propagation. Consistent resolution improvements of up to 2.2\u00d7 for both types of plasmonic fibers are found, demonstrating that deploying such analysis with any plasmonic optical fiber sensors can lead to sensing resolution improvements.<\/jats:p>","DOI":"10.3390\/s23031666","type":"journal-article","created":{"date-parts":[[2023,2,3]],"date-time":"2023-02-03T01:40:25Z","timestamp":1675388425000},"page":"1666","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Spectral Analysis Methods for Improved Resolution and Sensitivity: Enhancing SPR and LSPR Optical Fiber Sensing"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3826-7427","authenticated-orcid":false,"given":"Paulo S. S.","family":"Dos Santos","sequence":"first","affiliation":[{"name":"INESC TEC\u2014Institute for Systems and Computer Engineering, Technology and Science, Rua Dr. Alberto Frias, 4200-465 Porto, Portugal"},{"name":"FEUP, University of Porto, R. Dr. Roberto Frias, 4200-465 Porto, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1031-9261","authenticated-orcid":false,"given":"Jo\u00e3o P.","family":"Mendes","sequence":"additional","affiliation":[{"name":"INESC TEC\u2014Institute for Systems and Computer Engineering, Technology and Science, Rua Dr. Alberto Frias, 4200-465 Porto, Portugal"},{"name":"FCUP, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal"},{"name":"CIQUP\/IMS\u2014Chemistry Research Unit, FCUP, University of Porto, 4169-007 Porto, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3952-2311","authenticated-orcid":false,"given":"Bernardo","family":"Dias","sequence":"additional","affiliation":[{"name":"INESC TEC\u2014Institute for Systems and Computer Engineering, Technology and Science, Rua Dr. Alberto Frias, 4200-465 Porto, Portugal"},{"name":"FCUP, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4614-1699","authenticated-orcid":false,"given":"Jorge","family":"P\u00e9rez-Juste","sequence":"additional","affiliation":[{"name":"CINBIO, Universidade de Vigo, Campus Universitario Lagoas, Marcosende, 36310 Vigo, Spain"},{"name":"SERGAS-UVIGO, Galicia Sur Health Research Institute, 36312 Vigo, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3810-5943","authenticated-orcid":false,"given":"Jos\u00e9 M. M. M.","family":"De Almeida","sequence":"additional","affiliation":[{"name":"INESC TEC\u2014Institute for Systems and Computer Engineering, Technology and Science, Rua Dr. Alberto Frias, 4200-465 Porto, Portugal"},{"name":"Department of Physics, University of Tr\u00e1s-os-Montes e Alto Douro, 5001-801 Vila Real, Portugal"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1091-1364","authenticated-orcid":false,"given":"Isabel","family":"Pastoriza-Santos","sequence":"additional","affiliation":[{"name":"CINBIO, Universidade de Vigo, Campus Universitario Lagoas, Marcosende, 36310 Vigo, Spain"},{"name":"SERGAS-UVIGO, Galicia Sur Health Research Institute, 36312 Vigo, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6205-9479","authenticated-orcid":false,"given":"Luis C. 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