{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T17:22:36Z","timestamp":1776964956035,"version":"3.51.4"},"reference-count":34,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2020,1,22]],"date-time":"2020-01-22T00:00:00Z","timestamp":1579651200000},"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>This research demonstrated the development of a simple, cost-effective, and label-free immunosensor for the detection of \u03b1-synuclein (\u03b1-Syn) based on a cystamine (CYS) self-assembled monolayer (SAM) decorated fluorine-doped tin oxide (FTO) electrode. CYS-SAM was formed onto the FTO electrode by the adsorption of CYS molecules through the head sulfur groups. The free amine (\u2013NH2) groups at the tail of the CYS-SAM enabled the immobilization of anti-\u03b1-Syn-antibody, which concurrently allowed the formation of immunocomplex by covalent bonding with \u03b1-Syn-antigen. The variation of the concentrations of the attached \u03b1-Syn at the immunosensor probe induced the alternation of the current and the charge transfer resistance (Rct) for the redox response of [Fe(CN)6]3\u2212\/4\u2212, which displayed a linear dynamic range from 10 to 1000 ng\/mL with a low detection limit (S\/N = 3) of ca. 3.62 and 1.13 ng\/mL in differential pulse voltammetry (DPV) and electrochemical impedance spectra (EIS) measurements, respectively. The immunosensor displayed good reproducibility, anti-interference ability, and good recoveries of \u03b1-Syn detection in diluted human serum samples. The proposed immunosensor is a promising platform to detect \u03b1-Syn for the early diagnose of Parkinson\u2019s disease, which can be extended for the determination of other biologically important biomarkers.<\/jats:p>","DOI":"10.3390\/s20030617","type":"journal-article","created":{"date-parts":[[2020,1,22]],"date-time":"2020-01-22T11:17:57Z","timestamp":1579691877000},"page":"617","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":42,"title":["An Electrochemical Immunosensor Based on a Self-Assembled Monolayer Modified Electrode for Label-Free Detection of \u03b1-Synuclein"],"prefix":"10.3390","volume":"20","author":[{"given":"Chuang-Ye","family":"Ge","sequence":"first","affiliation":[{"name":"Department of Energy and Materials, Konkuk University, Chungju 380-701, Korea"},{"name":"Department of Chemistry and Chemical Engineering, Henan Institute of Science and Technology, Xinxiang 453003, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Md. Mahbubur","family":"Rahman","sequence":"additional","affiliation":[{"name":"Department of Energy and Materials, Konkuk University, Chungju 380-701, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wei","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Energy and Materials, Konkuk University, Chungju 380-701, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nasrin Siraj","family":"Lopa","sequence":"additional","affiliation":[{"name":"Department of Energy and Materials, Konkuk University, Chungju 380-701, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3778-1974","authenticated-orcid":false,"given":"Lei","family":"Jin","sequence":"additional","affiliation":[{"name":"Department of Energy and Materials, Konkuk University, Chungju 380-701, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sujin","family":"Yoon","sequence":"additional","affiliation":[{"name":"Department of Energy and Materials, Konkuk University, Chungju 380-701, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hohyoun","family":"Jang","sequence":"additional","affiliation":[{"name":"Department of Liberal Arts, Konkuk University,  Chungju-si 27478, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guang-Ri","family":"Xu","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Chemical Engineering, Henan Institute of Science and Technology, Xinxiang 453003, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0794-5301","authenticated-orcid":false,"given":"Whangi","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Energy and Materials, Konkuk University, Chungju 380-701, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,1,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1236","DOI":"10.1002\/elan.201400040","article-title":"Electroanalytical sensors and methods for assays and studies of neurological biomarkers","volume":"26","author":"Chen","year":"2014","journal-title":"Electroanalysis"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"363","DOI":"10.1016\/j.trac.2016.02.012","article-title":"Recent advances in biosensors for neurodegenerative disease detection","volume":"79","author":"Ganesh","year":"2016","journal-title":"Trends Anal. 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