{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T13:23:22Z","timestamp":1790083402106,"version":"4.0.1"},"reference-count":33,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2024,2,15]],"date-time":"2024-02-15T00:00:00Z","timestamp":1707955200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Natural Sciences and Engineering Research Council of Canada, Discovery Grant"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>Parkinson\u2019s Disease (PD) is a debilitating neurodegenerative disease, causing loss of motor function and, in some instances, cognitive decline and dementia in those affected. The quality of life can be improved, and disease progression delayed through early interventions. However, current methods of confirming a PD diagnosis are extremely invasive. This prevents their use as a screening tool for the early onset stages of PD. We propose a surface imprinted polymer (SIP) electroimpedance spectroscopy (EIS) biosensor for detecting \u03b1-Synuclein (\u03b1Syn) and its aggregates, a biomarker that appears in saliva and blood during the early stages of PD as the blood-brain barrier degrades. The surface imprinted polymer stamp is fabricated by low-temperature melt stamping polycaprolactone (PCL) on interdigitated EIS electrodes. The result is a low-cost, small-footprint biosensor that is highly suitable for non-invasive monitoring of the disease biomarker. The sensors were tested with \u03b1Syn dilutions in deionized water and in constant ionic concentration matrix solutions with decreasing concentrations of \u03b1Syn to remove the background effects of concentration. The device response confirmed the specificity of these devices to the target protein of monomeric \u03b1Syn. The sensor limit of detection was measured to be 5 pg\/L, and its linear detection range was 5 pg\/L\u20135 \u00b5g\/L. This covers the physiological range of \u03b1Syn in saliva and makes this a highly promising method of quantifying \u03b1Syn monomers for PD patients in the future. The SIP surface was regenerated, and the sensor was reused to demonstrate its capability for repeat sensing as a potential continuous monitoring tool for the disease biomarker.<\/jats:p>","DOI":"10.3390\/mi15020273","type":"journal-article","created":{"date-parts":[[2024,2,15]],"date-time":"2024-02-15T05:55:59Z","timestamp":1707976559000},"page":"273","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["A Surface Imprinted Polymer EIS Sensor for Detecting Alpha-Synuclein, a Parkinson\u2019s Disease Biomarker"],"prefix":"10.3390","volume":"15","author":[{"given":"Roslyn Simone","family":"Massey","sequence":"first","affiliation":[{"name":"Department of Electronics Engineering, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rishabh Ramesh","family":"Appadurai","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7934-425X","authenticated-orcid":false,"given":"Ravi","family":"Prakash","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"551","DOI":"10.1016\/S2468-2667(20)30190-0","article-title":"The burden of neurological diseases in Europe: An analysis for the Global Burden of Disease Study 2017","volume":"5","author":"Deuschl","year":"2020","journal-title":"Lancet Public Health"},{"key":"ref_2","unstructured":"(2023, November 17). 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