{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,8]],"date-time":"2026-02-08T17:16:19Z","timestamp":1770570979598,"version":"3.49.0"},"posted":{"date-parts":[[2026]]},"group-title":"SSRN","reference-count":40,"publisher":"Elsevier BV","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>Raman spectroscopy is a widely used technique to non-invasively characterize melanin pigment in biological and synthetic samples. However, its strong fluorescence and instrument-induced spectral artifacts hinder the retrieval of its Raman signal and its comparability between different studies. Here, we present a pre-processing and analytical strategy for a reliable signal retrieval and characterization of melanin Raman signatures in biological samples. The proposed workflow includes: (1) characterization of the Rayleigh filters to correct the sinusoidal modulation introduced by their transmittance ripple, (2) conservative fluorescence background removal adjusted to preserve the broad D and G Raman bands and, (3) identification and extraction of Raman and fluorescence features that remain stable across different acquisition parameters, to improve the comparability between different pigmented samples. Using hairs and feathers with different pigmentation and two different excitation wavelengths (532 nm and 785 nm), we demonstrate that, with the proposed methodology, the identification and retrieval of the melanin signal is improved, supporting a more reliable extraction of spectral features for pigment characterization. While describing each step, previous methodologies and results reported in melanin Raman literature are also discussed.<\/jats:p>","DOI":"10.2139\/ssrn.6193516","type":"posted-content","created":{"date-parts":[[2026,2,7]],"date-time":"2026-02-07T18:39:23Z","timestamp":1770489563000},"source":"Crossref","is-referenced-by-count":0,"title":["Correction of Rayleigh filter ripple and fluorescence background to enable reliable Raman analysis of melanin"],"prefix":"10.2139","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8983-3612","authenticated-orcid":true,"given":"Jos\u00e9 Javier","family":"Ruiz","sequence":"first","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6523-8592","authenticated-orcid":true,"given":"Ismael","family":"Galv\u00e1n","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3129-1213","authenticated-orcid":true,"given":"Pablo","family":"Loza-\u00c1lvarez","sequence":"additional","affiliation":[]}],"member":"78","reference":[{"key":"ref1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1155\/2014\/498276","article-title":"Melanins: Skin Pigments and Much More-Types, Structural Models, Biological Functions, and Formation Routes","volume":"2014","author":"F Solano","year":"2014","journal-title":"New J. 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