{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T00:39:42Z","timestamp":1792715982669,"version":"4.5.0"},"reference-count":49,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2024,6,4]],"date-time":"2024-06-04T00:00:00Z","timestamp":1717459200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>L-tryptophan is an amino acid that is essential to the metabolism of humans. Therefore, there is a high interest for its detection in biological fluids including blood, urine, and saliva for medical studies, but also in food products. Towards this goal, we report on a new electrochemiluminescence (ECL) method for L-tryptophan detection involving the in situ production of hydrogen peroxide at the surface of boron-doped diamond (BDD) electrodes. We demonstrate that the ECL response efficiency is directly related to H2O2 production at the electrode surface and propose a mechanism for the ECL emission of L-tryptophan. After optimizing the analytical conditions, we show that the ECL response to L-tryptophan is directly linear with concentration in the range of 0.005 to 1 \u00b5M. We achieved a limit of detection of 0.4 nM and limit of quantification of 1.4 nM in phosphate buffer saline (PBS, pH 7.4). Good selectivity against other indolic compounds (serotonin, 3-methylindole, tryptamine, indole) potentially found in biological fluids was observed, thus making this approach highly promising for quantifying L-tryptophan in a broad range of aqueous matrices of interest.<\/jats:p>","DOI":"10.3390\/s24113627","type":"journal-article","created":{"date-parts":[[2024,6,4]],"date-time":"2024-06-04T05:17:30Z","timestamp":1717478250000},"page":"3627","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Highly Sensitive and Selective Detection of L-Tryptophan by ECL Using Boron-Doped Diamond Electrodes"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9706-6564","authenticated-orcid":false,"given":"Emmanuel","family":"Scorsone","sequence":"first","affiliation":[{"name":"Universit\u00e9 Paris-Saclay, CEA, List, F-91120 Palaiseau, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Samuel","family":"Stewart","sequence":"additional","affiliation":[{"name":"Universit\u00e9 Paris-Saclay, CEA, List, F-91120 Palaiseau, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3499-3966","authenticated-orcid":false,"given":"Matthieu","family":"Hamel","sequence":"additional","affiliation":[{"name":"Universit\u00e9 Paris-Saclay, CEA, List, F-91120 Palaiseau, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,6,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8952520","DOI":"10.1155\/2016\/8952520","article-title":"Tryptophan biochemistry: Structural, nutritional, metabolic, and medical aspects in humans","volume":"2016","author":"Palego","year":"2016","journal-title":"J. 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