{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,2]],"date-time":"2026-05-02T06:58:21Z","timestamp":1777705101990,"version":"3.51.4"},"reference-count":25,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,1,23]],"date-time":"2025-01-23T00:00:00Z","timestamp":1737590400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia (FCT), Center of Technology and Systems (CTS)","award":["UIDB\/00066\/2020\/UIDP\/00066\/2020"],"award-info":[{"award-number":["UIDB\/00066\/2020\/UIDP\/00066\/2020"]}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia (FCT), Center of Technology and Systems (CTS)","award":["IPL\/2023\/IDI&CA"],"award-info":[{"award-number":["IPL\/2023\/IDI&CA"]}]},{"name":"Instituto Polit\u00e9cnico de Lisboa","award":["UIDB\/00066\/2020\/UIDP\/00066\/2020"],"award-info":[{"award-number":["UIDB\/00066\/2020\/UIDP\/00066\/2020"]}]},{"name":"Instituto Polit\u00e9cnico de Lisboa","award":["IPL\/2023\/IDI&CA"],"award-info":[{"award-number":["IPL\/2023\/IDI&CA"]}]},{"name":"Sapienza Visiting Professor Programme 2022","award":["UIDB\/00066\/2020\/UIDP\/00066\/2020"],"award-info":[{"award-number":["UIDB\/00066\/2020\/UIDP\/00066\/2020"]}]},{"name":"Sapienza Visiting Professor Programme 2022","award":["IPL\/2023\/IDI&CA"],"award-info":[{"award-number":["IPL\/2023\/IDI&CA"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The diagnosis of kidney diseases presents significant challenges, including the reliance on variable and unstable biomarkers and the necessity for complex and expensive laboratory tests. Raman spectroscopy emerges as a promising technique for analyzing complex fluids, like urine, and detecting important disease biomarkers. However, its complexity, high cost and limited accessibility outside clinical contexts complicate its application. Moreover, the analysis of Raman spectra is a challenging and intensive task. In response to these challenges, in this study, we developed a portable, simplified and low-cost Raman system designed to acquire high-quality spectra of liquid complex samples. Using the \u201cStarter Edition\u201d methodology from the OpenRAMAN project, the system was optimized through laser temperature adjustments, by evaluating the laser emission spectrum under different temperatures with a spectrometer, and through adjustment of the acquisition parameters of the software used, by acquiring the ethanol spectra. The system validation was performed through the acquisition of Raman spectra from five urine samples, demonstrating its consistency and sensitivity to composition variations in urine samples. Additionally, a neural network was designed and trained using methanol and ethanol solutions. The model\u2019s hyperparameters were optimized to maximize its precision and accuracy, achieving 99.19% accuracy and 99.21% precision, with a training time of approximately 3 min, underlining the model\u2019s potential for classifying simple Raman spectra. While further system validation with more samples, a more in-depth analysis of the biomarkers present in urine and the integration with more sophisticated elements are necessary, this approach demonstrates the system characteristics of affordability and portability, making it a suitable solution for point-of-care applications and offering simplified accessibility for assessing the diseases risk outside clinical contexts.<\/jats:p>","DOI":"10.3390\/s25030659","type":"journal-article","created":{"date-parts":[[2025,1,23]],"date-time":"2025-01-23T05:49:54Z","timestamp":1737611394000},"page":"659","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Low-Cost Raman Spectroscopy Setup Combined with a Machine Learning Model"],"prefix":"10.3390","volume":"25","author":[{"given":"Catarina","family":"Domingos","sequence":"first","affiliation":[{"name":"Department of Electronics, Telecommunication and Computers, Lisbon School of Engineering (ISEL), Polytechnic University of Lisbon (IPL), Rua Conselheiro Em\u00eddio Navarro, n\u00b01, 1959-007 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9938-0351","authenticated-orcid":false,"given":"Alessandro","family":"Fantoni","sequence":"additional","affiliation":[{"name":"Department of Electronics, Telecommunication and Computers, Lisbon School of Engineering (ISEL), Polytechnic University of Lisbon (IPL), Rua Conselheiro Em\u00eddio Navarro, n\u00b01, 1959-007 Lisbon, Portugal"},{"name":"Center of Technology and Systems (UNINOVA-CTS) and Associated Lab of Intelligent Systems (LASI), 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0765-474X","authenticated-orcid":false,"given":"Miguel","family":"Fernandes","sequence":"additional","affiliation":[{"name":"Department of Electronics, Telecommunication and Computers, Lisbon School of Engineering (ISEL), Polytechnic University of Lisbon (IPL), Rua Conselheiro Em\u00eddio Navarro, n\u00b01, 1959-007 Lisbon, Portugal"},{"name":"Center of Technology and Systems (UNINOVA-CTS) and Associated Lab of Intelligent Systems (LASI), 2829-516 Caparica, Portugal"}]},{"given":"Jorge","family":"Fidalgo","sequence":"additional","affiliation":[{"name":"Department of Electronics, Telecommunication and Computers, Lisbon School of Engineering (ISEL), Polytechnic University of Lisbon (IPL), Rua Conselheiro Em\u00eddio Navarro, n\u00b01, 1959-007 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8456-9995","authenticated-orcid":false,"given":"Sofia Azeredo","family":"Pereira","sequence":"additional","affiliation":[{"name":"iNOVA4Health, NOVA Medical School, Faculdade de Ci\u00eancias M\u00e9dicas, NMS, FCM, Universidade NOVA de Lisboa, 1169-056 Lisbon, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"193","DOI":"10.1038\/s41581-019-0247-z","article-title":"Long-term outcomes of acute kidney injury and strategies for improved care","volume":"16","author":"James","year":"2020","journal-title":"Nat. Rev. Nephrol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"52","DOI":"10.1038\/s41572-021-00284-z","article-title":"Acute kidney injury","volume":"7","author":"Kellum","year":"2021","journal-title":"Nat. Rev. Dis. Prim."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"481","DOI":"10.2215\/CJN.03520807","article-title":"Urinary Biomarkers for Acute Kidney Injury","volume":"3","author":"Coca","year":"2008","journal-title":"Clin. J. Am. Soc. Nephrol."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Turgut, F., Awad, A.S., and Abdel-Rahman, E.M. (2023). Acute Kidney Injury: Medical Causes and Pathogenesis. J. Clin. Med., 12.","DOI":"10.3390\/jcm12010375"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1681\/ASN.2010111124","article-title":"Imperfect Gold Standards for Kidney Injury Biomarker Evaluation","volume":"23","author":"Waikar","year":"2012","journal-title":"J. Am. Soc. Nephrol."},{"key":"ref_6","first-page":"166","article-title":"Acute Kidney Injury Biomarkers: From bench to clinical use","volume":"30","author":"Soto","year":"2016","journal-title":"Port. J. Nephrol. Hypertens."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2375741","DOI":"10.1080\/0886022X.2024.2375741","article-title":"Utilizing Raman spectroscopy for urinalysis to diagnose acute kidney injury stages in cardiac surgery patients","volume":"46","author":"Sharma","year":"2024","journal-title":"Ren. Fail."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"25888","DOI":"10.1039\/C8RA04491K","article-title":"Challenges in application of Raman spectroscopy to biology and materials","volume":"8","author":"Kuhar","year":"2018","journal-title":"RSC Adv."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Jeng, M.-J., Sharma, M., Lee, C.-C., Lu, Y.-S., Tsai, C.-L., Chang, C.-H., Chen, S.-W., Lin, R.-M., and Chang, L.-B. (2022). Raman Spectral Characterization of Urine for Rapid Diagnosis of Acute Kidney Injury. J. Clin. Med., 11.","DOI":"10.3390\/jcm11164829"},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Smith, E., and Dent, G. (2019). Modern Raman Spectroscopy\u2014A Practical Approach, Wiley. [2nd ed.].","DOI":"10.1002\/9781119440598"},{"key":"ref_11","unstructured":"R\u00fcdiger, P. (2007). Field Guide to Lasers, SPIE."},{"key":"ref_12","unstructured":"Ferraro, J.R., Nakamoto, K., and Brown, C.W. (2003). Introductory Raman Spectroscopy, Academic Press."},{"key":"ref_13","unstructured":"(2024, July 01). Starter Edition Assembly\u2014OpenRAMAN. Available online: https:\/\/www.open-raman.org\/build\/starter-edition\/assembly\/."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Fantoni, A., Fernandes, M., Fidalgo, J., Soto, M.K., Pereira, S.A., Moreno, A., Domingos, C., Correia, A.R., Sousa, H., and Serafinelli, C. (2024, January 7\u201312). The LUMINA setup for a light-based urine monitoring and analysis. Proceedings of the SPIE, Biophotonics in Point-of-Care III, Strasbourg, France.","DOI":"10.1117\/12.3022182"},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Hoffmann, G.G. (2023). Infrared and Raman Spectroscopy: Principles and Applications, Walter de Gruyter.","DOI":"10.1515\/9783110717556"},{"key":"ref_16","unstructured":"(2024, September 23). Spectrum Analyzer Suite. Available online: https:\/\/www.open-raman.org\/build\/software\/."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"141","DOI":"10.1039\/b304992b","article-title":"Raman spectroscopy for identification of epithelial cancers","volume":"126","author":"Stone","year":"2003","journal-title":"Faraday Discuss."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Bispo, J.A.M., Vieira, E.E.d.S., Silveira, L., and Fernandes, A.B. (2013). Correlating the amount of urea, creatinine, and glucose in urine from patients with diabetes mellitus and hypertension with the risk of developing renal lesions by means of Raman spectroscopy and principal component analysis. J. Biomed. Opt., 18.","DOI":"10.1117\/1.JBO.18.8.087004"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"164043","DOI":"10.1016\/j.ijleo.2019.164043","article-title":"Urine Raman spectroscopy for rapid and inexpensive diagnosis of chronic renal failure (CRF) using multiple classification algorithms","volume":"203","author":"Chen","year":"2019","journal-title":"Optik"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1002\/(SICI)1520-6343(1997)3:2<113::AID-BSPY4>3.0.CO;2-8","article-title":"Quantitative analysis of metabolites in urine by anti-Stokes Raman spectroscopy","volume":"3","author":"Dou","year":"1998","journal-title":"Biospectroscopy"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"102445","DOI":"10.1016\/j.amsu.2021.102445","article-title":"Methanol poisoning as a new world challenge: A review","volume":"66","author":"Nekoukar","year":"2021","journal-title":"Ann. Med. Surg."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"065330","DOI":"10.1063\/1.5140722","article-title":"Raman study of mixed solutions of methanol and ethanol","volume":"10","author":"Emin","year":"2020","journal-title":"AIP Adv."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"563","DOI":"10.1191\/096032701718620864","article-title":"Defining a tolerable concentration of methanol in alcoholic drinks","volume":"20","author":"Paine","year":"2001","journal-title":"Hum. Exp. Toxicol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"324","DOI":"10.1039\/C8AN01702F","article-title":"Rapid through-container detection of fake spirits and methanol quantification with handheld Raman spectroscopy","volume":"144","author":"Ellis","year":"2018","journal-title":"Analyst"},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Ellis, D.I., Eccles, R., Xu, Y., Griffen, J., Muhamadali, H., Matousek, P., Goodall, I., and Goodacre, R. (2017). Through-container, extremely low concentration detection of multiple chemical markers of counterfeit alcohol using a handheld SORS device. Sci. Rep., 7.","DOI":"10.1038\/s41598-017-12263-0"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/25\/3\/659\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,8]],"date-time":"2025-10-08T10:34:19Z","timestamp":1759919659000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/25\/3\/659"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,1,23]]},"references-count":25,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2025,2]]}},"alternative-id":["s25030659"],"URL":"https:\/\/doi.org\/10.3390\/s25030659","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,1,23]]}}}