{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T09:36:22Z","timestamp":1780392982809,"version":"3.54.1"},"reference-count":51,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2021,7,18]],"date-time":"2021-07-18T00:00:00Z","timestamp":1626566400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"H2020 Laserlab Europe","award":["EC-GA 871124"],"award-info":[{"award-number":["EC-GA 871124"]}]},{"name":"H2020 FETOPEN project \u201cDynamic\u201d","award":["EC-GA-863203"],"award-info":[{"award-number":["EC-GA-863203"]}]},{"name":"NSRF 2014-2020 \u201cBIOIMAGING-GR\u201d","award":["MIS 5002755"],"award-info":[{"award-number":["MIS 5002755"]}]},{"name":"HELLAS CH","award":["MIS 5002735"],"award-info":[{"award-number":["MIS 5002735"]}]},{"name":"INNOVAPROTECT","award":["MIS 5030524"],"award-info":[{"award-number":["MIS 5030524"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The unique ability of photoacoustic (PA) sensing to provide optical absorption information of biomolecules deep inside turbid tissues with high sensitivity has recently enabled the development of various novel diagnostic systems for biomedical applications. In many cases, PA setups can be bulky, complex, and costly, as they typically require the integration of expensive Q-switched nanosecond lasers, and also presents limited wavelength availability. This article presents a compact, cost-efficient, multiwavelength PA sensing system for quantitative measurements, by utilizing two high-power LED sources emitting at central wavelengths of 444 and 628 nm, respectively, and a single-element ultrasonic transducer at 3.5 MHz for signal detection. We investigate the performance of LEDs in pulsed mode and explore the dependence of PA responses on absorber\u2019s concentration and applied energy fluence using tissue-mimicking phantoms demonstrating both optical absorption and scattering properties. Finally, we apply the developed system on the spectral unmixing of two absorbers contained at various relative concentrations in the phantoms, to provide accurate estimations with absolute deviations ranging between 0.4 and 12.3%. An upgraded version of the PA system may provide valuable in-vivo multiparametric measurements of important biomarkers, such as hemoglobin oxygenation, melanin concentration, local lipid content, and glucose levels.<\/jats:p>","DOI":"10.3390\/s21144888","type":"journal-article","created":{"date-parts":[[2021,7,18]],"date-time":"2021-07-18T21:18:52Z","timestamp":1626643132000},"page":"4888","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["A Cost-Efficient Multiwavelength LED-Based System for Quantitative Photoacoustic Measurements"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8220-7659","authenticated-orcid":false,"given":"Michalis","family":"Orfanakis","sequence":"first","affiliation":[{"name":"Foundation for Research and Technology Hellas, Institute of Electronic Structure and Laser, N. Plastira 100, GR-70013 Heraklion, Greece"},{"name":"School of Medicine, University of Crete, GR-71003 Heraklion, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9938-3472","authenticated-orcid":false,"given":"George J.","family":"Tserevelakis","sequence":"additional","affiliation":[{"name":"Foundation for Research and Technology Hellas, Institute of Electronic Structure and Laser, N. Plastira 100, GR-70013 Heraklion, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giannis","family":"Zacharakis","sequence":"additional","affiliation":[{"name":"Foundation for Research and Technology Hellas, Institute of Electronic Structure and Laser, N. Plastira 100, GR-70013 Heraklion, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,18]]},"reference":[{"key":"ref_1","unstructured":"Wang, L.V., and Wu, H.I. (2012). 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