{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T18:18:00Z","timestamp":1788977880500,"version":"build-2803163510"},"reference-count":26,"publisher":"Public Library of Science (PLoS)","issue":"7","license":[{"start":{"date-parts":[[2021,7,22]],"date-time":"2021-07-22T00:00:00Z","timestamp":1626912000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002347","name":"Bundesministerium f\u00fcr Bildung und Forschung","doi-asserted-by":"publisher","award":["03ZZ0914D"],"award-info":[{"award-number":["03ZZ0914D"]}],"id":[{"id":"10.13039\/501100002347","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:p>Chronic infections are often connected to biofilm formation. In presence of implants, this can lead to loss of the implant. Systemic or local application of drugs is relatively ineffective in case of biofilm formation. One technique to provide antibacterial properties on demand is the antibacterial photodynamic therapy (aPDT). Using this technique, these properties can be \u201cswitched on\u201d by light illumination. In the middle ear with the semitransparent tympanic membrane, it might be possible in future to activate the antibacterial effect without opening the membrane. Therefore, we investigated the optical absorbance spectra of the tympanic membrane. Optical absorbance spectra were measured in <jats:italic>ex vivo<\/jats:italic> preparations from neonatal and adult rats with the membrane still being attached to the surrounding bony ring and four human samples. After performing area scans, the spot with the lowest absorbance being surrounded by a ring like structure with higher absorbance was chosen as region of interest for scanning wavelengths between 300 and 900 nm. Absorbance is generally higher at lower wavelengths with a local absorbance maximum at 420 nm and a weak second maximum with two neighbouring peaks at 540 \/ 580 nm and is significantly higher in adult rats compared to neonatal rats where about 10% of light was transmitted. The human samples show similar characteristics with a little higher absorbance. For activation of aPDT through the tympanic membrane, larger wavelengths are more promising. Whether the amount of light transmitted through the membrane would be sufficient to induce aPDT remains to be tested in further experiments.<\/jats:p>","DOI":"10.1371\/journal.pone.0254902","type":"journal-article","created":{"date-parts":[[2021,7,22]],"date-time":"2021-07-22T17:38:46Z","timestamp":1626975526000},"page":"e0254902","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":4,"title":["Optical absorbance of the tympanic membrane in rat and human samples"],"prefix":"10.1371","volume":"16","author":[{"given":"Madeleine","family":"Goblet","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Farnaz","family":"Matin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Lenarz","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3532-9426","authenticated-orcid":true,"given":"Gerrit","family":"Paasche","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2021,7,22]]},"reference":[{"key":"pone.0254902.ref001","doi-asserted-by":"crossref","first-page":"1518","DOI":"10.1016\/j.jbiomech.2016.03.030","article-title":"Effects of the fibers distribution in the human eardrum: A biomechanical study","volume":"49","author":"F Gentil","year":"2016","journal-title":"J Biomech"},{"key":"pone.0254902.ref002","doi-asserted-by":"crossref","first-page":"1531","DOI":"10.1002\/ar.23461","article-title":"Fiber Arrangement in the Rat Tympanic Membrane","volume":"299","author":"J Liu","year":"2016","journal-title":"Anat Rec"},{"key":"pone.0254902.ref003","doi-asserted-by":"crossref","first-page":"1219","DOI":"10.1016\/j.jbiomech.2010.12.023","article-title":"Biomechanics of the tympanic membrane","volume":"44","author":"G Volandri","year":"2011","journal-title":"J Biomech"},{"key":"pone.0254902.ref004","doi-asserted-by":"crossref","first-page":"1473","DOI":"10.1088\/0967-3334\/25\/6\/012","article-title":"Diffuse reflectance spectroscopy of the human tympanic membrane in otitis media","volume":"25","author":"M Sundberg","year":"2004","journal-title":"Physiol Meas"},{"key":"pone.0254902.ref005","first-page":"1","article-title":"Otitis media","volume":"2","author":"AGM Schilder","year":"2016","journal-title":"Nat Rev Dis Prim"},{"key":"pone.0254902.ref006","article-title":"Otitis media","author":"MM Rovers","year":"2004","journal-title":"Lancet"},{"key":"pone.0254902.ref007","first-page":"40","article-title":"Otitis media with effusion in children: Diagnosis","volume":"26","author":"JM Triglia","year":"1996","journal-title":"Med Mal Infect"},{"key":"pone.0254902.ref008","doi-asserted-by":"crossref","first-page":"93031F","DOI":"10.1117\/12.2079761","article-title":"A compact structured light based otoscope for three dimensional imaging of the tympanic membrane","volume":"9303","author":"AJ Das","year":"2015","journal-title":"Photonic Ther Diagnostics XI"},{"key":"pone.0254902.ref009","article-title":"Clinical Practice Guideline","author":"RM Rosenfeld","year":"2016","journal-title":"Otolaryngology\u2014Head and Neck Surgery (United States)"},{"key":"pone.0254902.ref010","doi-asserted-by":"crossref","first-page":"539","DOI":"10.1097\/MAO.0b013e3182829792","article-title":"Bacterial growth on cochlear implants as a potential origin of complications","volume":"34","author":"N Kanaan","year":"2013","journal-title":"Otol Neurotol"},{"key":"pone.0254902.ref011","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1016\/j.joto.2019.01.005","article-title":"Otitis media with effusion in children: Pathophysiology, diagnosis, and treatment. 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