{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T15:18:34Z","timestamp":1768403914367,"version":"3.49.0"},"reference-count":33,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2022,3,10]],"date-time":"2022-03-10T00:00:00Z","timestamp":1646870400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["CEECIND\/00154\/2020"],"award-info":[{"award-number":["CEECIND\/00154\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["CEECIND\/00034\/2018"],"award-info":[{"award-number":["CEECIND\/00034\/2018"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/50025\/2020 & UIDP\/50025\/2020"],"award-info":[{"award-number":["UIDB\/50025\/2020 & UIDP\/50025\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Optical fiber technology has rapidly progressed over the years, providing valuable benefits for biosensing purposes such as sensor miniaturization and the possibility for remote and real-time monitoring. In particular, tilted fiber Bragg gratings (TFBGs) are extremely sensitive to refractive index variations taking place on their surface. The present work comprises a case-study on the impact of different methods of analysis applied to decode spectral variations of bare and plasmonic TFBGs during the detection of N-terminal B-type natriuretic peptide (NT-proBNP), a heart failure biomarker, namely by following the most sensitive mode, peaks of the spectral envelopes, and the envelopes\u2019 crossing point and area. Tracking the lower envelope resulted in the lowest limits of detection (LOD) for bare and plasmonic TFBGs, namely, 0.75 ng\/mL and 0.19 ng\/mL, respectively. This work demonstrates the importance of the analysis method on the outcome results, which is crucial to attain the most reliable and sensitive method with lower LOD sensors. Furthermore, it makes the scientific community aware to take careful attention when comparing the performance of different biosensors in which different analysis methods were used.<\/jats:p>","DOI":"10.3390\/s22062141","type":"journal-article","created":{"date-parts":[[2022,3,10]],"date-time":"2022-03-10T20:19:10Z","timestamp":1646943550000},"page":"2141","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Relevance of the Spectral Analysis Method of Tilted Fiber Bragg Grating-Based Biosensors: A Case-Study for Heart Failure Monitoring"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5890-2566","authenticated-orcid":false,"given":"Miguel","family":"Vidal","sequence":"first","affiliation":[{"name":"Physics Department & I3N, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2752-1629","authenticated-orcid":false,"given":"Maria Simone","family":"Soares","sequence":"additional","affiliation":[{"name":"Physics Department & I3N, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8858-7413","authenticated-orcid":false,"given":"M\u00e9d\u00e9ric","family":"Loyez","sequence":"additional","affiliation":[{"name":"Electromagnetism and Telecommunication Department, University of Mons, 31 Bld Dolez, 7000 Mons, Belgium"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8729-714X","authenticated-orcid":false,"given":"Florinda M.","family":"Costa","sequence":"additional","affiliation":[{"name":"Physics Department & I3N, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Christophe","family":"Caucheteur","sequence":"additional","affiliation":[{"name":"Electromagnetism and Telecommunication Department, University of Mons, 31 Bld Dolez, 7000 Mons, Belgium"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8596-5092","authenticated-orcid":false,"given":"Carlos","family":"Marques","sequence":"additional","affiliation":[{"name":"Physics Department & I3N, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4174-7253","authenticated-orcid":false,"given":"S\u00f3nia O.","family":"Pereira","sequence":"additional","affiliation":[{"name":"Physics Department & I3N, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6331-1215","authenticated-orcid":false,"given":"C\u00e1tia","family":"Leit\u00e3o","sequence":"additional","affiliation":[{"name":"Physics Department & I3N, University of Aveiro, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1605","DOI":"10.1039\/C9AN01998G","article-title":"Optical biosensors: An exhaustive and comprehensive review","volume":"145","author":"Chen","year":"2020","journal-title":"Analyst"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Soares, M.S., Vidal, M., Santos, N.F., Costa, F.M., Marques, C., Pereira, S.O., and Leit\u00e3o, C. 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