{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,12]],"date-time":"2026-09-12T04:11:40Z","timestamp":1789186300938,"version":"build-2803163510"},"reference-count":47,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2020,9,21]],"date-time":"2020-09-21T00:00:00Z","timestamp":1600646400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000266","name":"Engineering and Physical Sciences Research Council","doi-asserted-by":"publisher","award":["EP\/R003750\/1"],"award-info":[{"award-number":["EP\/R003750\/1"]}],"id":[{"id":"10.13039\/501100000266","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Uninterrupted monitoring of serum lactate levels is a prerequisite in the critical care of patients prone to sepsis, cardiogenic shock, cardiac arrest, or severe lung disease. Yet there exists no device to continuously measure blood lactate in clinical practice. Optical spectroscopy together with multivariate analysis is proposed as a viable noninvasive tool for estimation of lactate in blood. As an initial step towards this goal, we inspected the plausibility of predicting the concentration of sodium lactate (NaLac) from the UV\/visible, near-infrared (NIR), and mid-infrared (MIR) spectra of 37 isotonic phosphate-buffered saline (PBS) samples containing NaLac ranging from 0 to 20 mmol\/L. UV\/visible (300\u2013800 nm) and NIR (800\u20132600 nm) spectra of PBS samples were collected using the PerkinElmer Lambda 1050 dual-beam spectrophotometer, while MIR (4000\u2013500 cm\u22121) spectra were collected using the Spectrum two FTIR spectrometer. Absorption bands in the spectra of all three regions were identified and functional groups were assigned. The concentration of lactate in samples was predicted using the Partial Least-Squares (PLS) regression analysis and leave-one-out cross-validation. The regression analysis showed a correlation coefficient (R2) of 0.926, 0.977, and 0.992 for UV\/visible, NIR, and MIR spectra, respectively, between the predicted and reference samples. The RMSECV of UV\/visible, NIR, and MIR spectra was 1.59, 0.89, and 0.49 mmol\/L, respectively. The results indicate that optical spectroscopy together with multivariate models can achieve a superior technique in assessing lactate concentrations.<\/jats:p>","DOI":"10.3390\/s20185402","type":"journal-article","created":{"date-parts":[[2020,9,21]],"date-time":"2020-09-21T08:18:01Z","timestamp":1600676281000},"page":"5402","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Identification and Quantitative Determination of Lactate Using Optical Spectroscopy\u2014Towards a Noninvasive Tool for Early Recognition of Sepsis"],"prefix":"10.3390","volume":"20","author":[{"given":"Karthik","family":"Budidha","sequence":"first","affiliation":[{"name":"Research Centre for Biomedical Engineering, School of Engineering and Mathematical Sciences, University of London, Northampton Square, London EC1V 0HB, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammad","family":"Mamouei","sequence":"additional","affiliation":[{"name":"Research Centre for Biomedical Engineering, School of Engineering and Mathematical Sciences, University of London, Northampton Square, London EC1V 0HB, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2231-6132","authenticated-orcid":false,"given":"Nystha","family":"Baishya","sequence":"additional","affiliation":[{"name":"Research Centre for Biomedical Engineering, School of Engineering and Mathematical Sciences, University of London, Northampton Square, London EC1V 0HB, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Meha","family":"Qassem","sequence":"additional","affiliation":[{"name":"Research Centre for Biomedical Engineering, School of Engineering and Mathematical Sciences, University of London, Northampton Square, London EC1V 0HB, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6696-6017","authenticated-orcid":false,"given":"Pankaj","family":"Vadgama","sequence":"additional","affiliation":[{"name":"Interdisciplinary Research Centre (IRC) in Biomedical Materials, Queen Mary University of London (QMUL), Mile End Road, London E1 4NS, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2868-485X","authenticated-orcid":false,"given":"Panayiotis A.","family":"Kyriacou","sequence":"additional","affiliation":[{"name":"Research Centre for Biomedical Engineering, School of Engineering and Mathematical Sciences, University of London, Northampton Square, London EC1V 0HB, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,9,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"106","DOI":"10.1111\/vec.12706","article-title":"Clinical use of plasma lactate concentration. 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