{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T05:18:07Z","timestamp":1784092687403,"version":"3.55.0"},"reference-count":36,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2021,7,27]],"date-time":"2021-07-27T00:00:00Z","timestamp":1627344000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002347","name":"Bundesministerium f\u00fcr Bildung und Forschung","doi-asserted-by":"publisher","award":["13GW0096A"],"award-info":[{"award-number":["13GW0096A"]}],"id":[{"id":"10.13039\/501100002347","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Raman spectroscopy probes the biochemical composition of samples in a non-destructive, non-invasive and label-free fashion yielding specific information on a molecular level. Nevertheless, the Raman effect is very weak. The detection of all inelastically scattered photons with highest efficiency is therefore crucial as well as the identification of all noise sources present in the system. Here we provide a study for performance comparison and assessment of different spectrometers for confocal Raman spectroscopy in biosensor applications. A low-cost, home-built Raman spectrometer with a complementary metal-oxide-semiconductor (CMOS) camera, a middle price-class mini charge-coupled device (CCD) Raman spectrometer and a laboratory grade confocal Raman system with a deeply cooled CCD detector are compared. It is often overlooked that the sample itself is the most important \u201coptical\u201d component in a Raman spectrometer and its properties contribute most significantly to the signal-to-noise ratio. For this purpose, different representative samples: a crystalline silicon wafer, a polypropylene sample and E. coli bacteria were measured under similar conditions using the three confocal Raman spectrometers. We show that biosensor applications do not in every case profit from the most expensive equipment. Finally, a small Raman database of three different bacteria species is set up with the middle price-class mini CCD Raman spectrometer in order to demonstrate the potential of a compact setup for pathogen discrimination.<\/jats:p>","DOI":"10.3390\/s21155067","type":"journal-article","created":{"date-parts":[[2021,7,27]],"date-time":"2021-07-27T03:53:53Z","timestamp":1627358033000},"page":"5067","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Noise Sources and Requirements for Confocal Raman Spectrometers in Biosensor Applications"],"prefix":"10.3390","volume":"21","author":[{"given":"Izabella J.","family":"Jahn","sequence":"first","affiliation":[{"name":"Leibniz Institute of Photonic Technology (Leibniz-IPHT), a Member of the Leibniz Research Alliance Leibniz Health Technology, Albert-Einstein-Stra\u00dfe 9, 07745 Jena, Germany"},{"name":"InfectoGnostics Research Campus Jena, Centre for Applied Research, Philosophenweg 7, 07743 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9876-3764","authenticated-orcid":false,"given":"Alexej","family":"Grjasnow","sequence":"additional","affiliation":[{"name":"Leibniz Institute of Photonic Technology (Leibniz-IPHT), a Member of the Leibniz Research Alliance Leibniz Health Technology, Albert-Einstein-Stra\u00dfe 9, 07745 Jena, Germany"},{"name":"InfectoGnostics Research Campus Jena, Centre for Applied Research, Philosophenweg 7, 07743 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9098-4642","authenticated-orcid":false,"given":"Henry","family":"John","sequence":"additional","affiliation":[{"name":"Leibniz Institute of Photonic Technology (Leibniz-IPHT), a Member of the Leibniz Research Alliance Leibniz Health Technology, Albert-Einstein-Stra\u00dfe 9, 07745 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karina","family":"Weber","sequence":"additional","affiliation":[{"name":"Leibniz Institute of Photonic Technology (Leibniz-IPHT), a Member of the Leibniz Research Alliance Leibniz Health Technology, Albert-Einstein-Stra\u00dfe 9, 07745 Jena, Germany"},{"name":"InfectoGnostics Research Campus Jena, Centre for Applied Research, Philosophenweg 7, 07743 Jena, Germany"},{"name":"Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4257-593X","authenticated-orcid":false,"given":"J\u00fcrgen","family":"Popp","sequence":"additional","affiliation":[{"name":"Leibniz Institute of Photonic Technology (Leibniz-IPHT), a Member of the Leibniz Research Alliance Leibniz Health Technology, Albert-Einstein-Stra\u00dfe 9, 07745 Jena, Germany"},{"name":"InfectoGnostics Research Campus Jena, Centre for Applied Research, Philosophenweg 7, 07743 Jena, Germany"},{"name":"Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9039-0417","authenticated-orcid":false,"given":"Walter","family":"Hauswald","sequence":"additional","affiliation":[{"name":"Leibniz Institute of Photonic Technology (Leibniz-IPHT), a Member of the Leibniz Research Alliance Leibniz Health Technology, Albert-Einstein-Stra\u00dfe 9, 07745 Jena, Germany"},{"name":"InfectoGnostics Research Campus Jena, Centre for Applied Research, Philosophenweg 7, 07743 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"82","DOI":"10.1016\/j.flm.2017.06.003","article-title":"Label-free techniques for laboratory medicine applications","volume":"1","author":"Chen","year":"2017","journal-title":"Front. 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A"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/15\/5067\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:35:22Z","timestamp":1760164522000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/15\/5067"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,7,27]]},"references-count":36,"journal-issue":{"issue":"15","published-online":{"date-parts":[[2021,8]]}},"alternative-id":["s21155067"],"URL":"https:\/\/doi.org\/10.3390\/s21155067","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,7,27]]}}}