{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,13]],"date-time":"2026-02-13T04:49:47Z","timestamp":1770958187320,"version":"3.50.1"},"reference-count":113,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,10,23]],"date-time":"2025-10-23T00:00:00Z","timestamp":1761177600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Photochem"],"abstract":"<jats:p>Experimental analysis of the viscoelastic properties of natural polymers over different testing durations and response time scales yields complementary insights into their static and dynamic mechanical behavior. Within this context, Brillouin spectroscopy has emerged as a contactless, non-invasive and label-free tool for the mechanical characterization of materials. In this review article, we provide a comprehensive overview of recent advances in Brillouin spectroscopy techniques applied to various natural polymers, including proteins, carbohydrates, and polysaccharides. We discuss the principles of Brillouin scattering and their application in investigating the mechanical properties of natural polymers. Additionally, we explore future perspectives and challenges. This review aims to provide researchers and practitioners with a comprehensive understanding of the capabilities and limitations of Brillouin spectroscopy for the mechanical characterization of natural polymers, promoting new advances in this interdisciplinary field.<\/jats:p>","DOI":"10.3390\/photochem5040034","type":"journal-article","created":{"date-parts":[[2025,10,24]],"date-time":"2025-10-24T01:35:11Z","timestamp":1761269711000},"page":"34","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Mechanical Characterization of Natural Polymers Using Brillouin Spectroscopy: A Comprehensive Review"],"prefix":"10.3390","volume":"5","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2527-5006","authenticated-orcid":false,"given":"Jos\u00e9 A.","family":"Rodrigues","sequence":"first","affiliation":[{"name":"CMEMS-UMinho, University of Minho, 4800-058 Guimar\u00e3es, Portugal"},{"name":"LABBELS-Associate Laboratory, Braga\/Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3643-2935","authenticated-orcid":false,"given":"Bruno","family":"Esteves","sequence":"additional","affiliation":[{"name":"CMEMS-UMinho, University of Minho, 4800-058 Guimar\u00e3es, Portugal"},{"name":"LABBELS-Associate Laboratory, Braga\/Guimar\u00e3es, Portugal"}]},{"given":"Patr\u00edcia","family":"Costa","sequence":"additional","affiliation":[{"name":"CMEMS-UMinho, University of Minho, 4800-058 Guimar\u00e3es, Portugal"},{"name":"LABBELS-Associate Laboratory, Braga\/Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5991-1069","authenticated-orcid":false,"given":"Jos\u00e9 H.","family":"Correia","sequence":"additional","affiliation":[{"name":"CMEMS-UMinho, University of Minho, 4800-058 Guimar\u00e3es, Portugal"},{"name":"LABBELS-Associate Laboratory, Braga\/Guimar\u00e3es, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"45","DOI":"10.1016\/j.cobme.2019.02.004","article-title":"Key terminology in biomaterials and biocompatibility","volume":"10","author":"Kolahreez","year":"2019","journal-title":"Curr. 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