{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,11]],"date-time":"2026-04-11T08:05:22Z","timestamp":1775894722306,"version":"3.50.1"},"reference-count":51,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2014,12,8]],"date-time":"2014-12-08T00:00:00Z","timestamp":1417996800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Photonics"],"abstract":"<jats:p>This review is focused on microstructured optical fiber sensors developed in recent years for liquid RI sensing. The review is divided into three parts: the first section introduces a general view of the most relevant refractometric sensors that have been reported over the last thirty years. Section 2 discusses several microstructured optical fiber designs, namely, suspended-core fiber, photonic crystal fiber, large-core air-clad photonic crystal fiber, and others. This part is also divided into two main groups: the interferometric-based and resonance-based configurations. The sensing methods rely either on full\/selective filling of the microstructured fiber air holes with a liquid analyte or by simply immersing the sensing fiber into the liquid analyte. The sensitivities and resolutions are tabled at the end of this section followed by a brief discussion of the obtained results. The last section concludes with some remarks about the microstructured fiber-based configurations developed for RI sensing and their potential for future applications.<\/jats:p>","DOI":"10.3390\/photonics1040516","type":"journal-article","created":{"date-parts":[[2014,12,8]],"date-time":"2014-12-08T11:15:56Z","timestamp":1418037356000},"page":"516-529","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":32,"title":["Refractive Index Measurement of Liquids Based on Microstructured Optical Fibers"],"prefix":"10.3390","volume":"1","author":[{"given":"Susana","family":"Silva","sequence":"first","affiliation":[{"name":"INESC Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal"}]},{"given":"Paulo","family":"Roriz","sequence":"additional","affiliation":[{"name":"INESC Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal"},{"name":"ISMAI\u2212Instituto Universit\u00e1rio da Maia, Av. Carlos Oliveira Campos\u2212Castelo da Maia,  4475-690 Maia, Portugal"}]},{"given":"Orlando","family":"Fraz\u00e3o","sequence":"additional","affiliation":[{"name":"INESC Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal"},{"name":"Departamento de F\u00edsica e Astronomia da Faculdade de Ci\u00eancias, Universidade do Porto,  Rua do Campo Alegre 687, 4169-007 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2014,12,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"299","DOI":"10.1117\/1.1637903","article-title":"Fibre Bragg grating sensing system for simultaneous measurement of salinity and temperature","volume":"43","author":"Pereira","year":"2004","journal-title":"Opt. 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