{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,31]],"date-time":"2026-01-31T03:26:54Z","timestamp":1769830014913,"version":"3.49.0"},"reference-count":39,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2017,6,22]],"date-time":"2017-06-22T00:00:00Z","timestamp":1498089600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["U01 NS090455"],"award-info":[{"award-number":["U01 NS090455"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["NIMHHD 2G12MD007592"],"award-info":[{"award-number":["NIMHHD 2G12MD007592"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Combined theoretical and experimental analysis of serotonin by quantum chemical density functional calculations and surface-enhanced Raman spectroscopy, respectively, is presented in this work to better understand phenomena related to this neurotransmitter\u2019s detection and monitoring at very low concentrations specific to physiological levels. In addition to the successful ultrasensitive analyte detection on silver nanoparticles for concentrations as low as 10\u221211 molar, the relatively good agreement between the simulated and experimentally determined results indicates the presence of all serotonin molecular forms, such as neutral, ionic, and those oxidized through redox reactions. Obvious structural molecular deformations such as bending of lateral amino chains are observed for both ionic and oxidized forms. Not only does this combined approach reveal more probable adsorption of serotonin into the silver surface through hydroxyl\/oxygen sites than through NH\/nitrogen sites, but also that it does so predominantly in its neutral (reduced) form, somewhat less so in its ionic forms, and much less in its oxidized forms. If the development of opto-voltammetric biosensors and their effective implementation is envisioned for the future, this study provides some needed scientific background for comprehending changes in the vibrational signatures of this important neurotransmitter.<\/jats:p>","DOI":"10.3390\/s17071471","type":"journal-article","created":{"date-parts":[[2017,6,22]],"date-time":"2017-06-22T10:11:35Z","timestamp":1498126295000},"page":"1471","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Analysis of Serotonin Molecules on Silver Nanocolloids\u2014A Raman Computational and Experimental Study"],"prefix":"10.3390","volume":"17","author":[{"given":"Felicia","family":"Manciu","sequence":"first","affiliation":[{"name":"Department of Physics, University of Texas at El Paso, El Paso, TX 79968, USA"},{"name":"Department of Biomedical Engineering, University of Texas at El Paso, El Paso, TX 79968, USA"},{"name":"Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX 79968, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"John","family":"Ciubuc","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Texas at El Paso, El Paso, TX 79968, USA"},{"name":"Department of Biomedical Engineering, University of Texas at El Paso, El Paso, TX 79968, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Emma","family":"Sundin","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Texas at El Paso, El Paso, TX 79968, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chao","family":"Qiu","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Texas at El Paso, El Paso, TX 79968, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kevin","family":"Bennet","sequence":"additional","affiliation":[{"name":"Division of Engineering, Department of Neurologic Surgery, Mayo Clinic, Rochester, MN 55905, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,6,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"352","DOI":"10.1113\/jphysiol.1953.sp004850","article-title":"Distribution of 5-hydroxytryptamine (serotonin, enteramine) in the wall of the digestive tract","volume":"119","author":"Feldberg","year":"1953","journal-title":"J. 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