{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,24]],"date-time":"2026-02-24T09:09:59Z","timestamp":1771924199754,"version":"3.50.1"},"reference-count":52,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2018,1,20]],"date-time":"2018-01-20T00:00:00Z","timestamp":1516406400000},"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\/M006301\/1"],"award-info":[{"award-number":["EP\/M006301\/1"]}],"id":[{"id":"10.13039\/501100000266","id-type":"DOI","asserted-by":"publisher"}]},{"name":"EU H2020 MSCA-ITN-ETN BBDiag","award":["721281"],"award-info":[{"award-number":["721281"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Clusterin (CLU) has been associated with the clinical progression of Alzheimer\u2019s disease (AD) and described as a potential AD biomarker in blood plasma. Due to the enormous attention given to cerebrospinal fluid (CSF) biomarkers for the past couple of decades, recently found blood-based AD biomarkers like CLU have not yet been reported for biosensors. Herein, we report the electrochemical detection of CLU for the first time using a screen-printed carbon electrode (SPCE) modified with 1-pyrenebutyric acid N-hydroxysuccinimide ester (Pyr-NHS) and decorated with specific anti-CLU antibody fragments. This bifunctional linker molecule contains succinylimide ester to bind protein at one end while its pyrene moiety attaches to the carbon surface by means of \u03c0-\u03c0 stacking. Cyclic voltammetric and square wave voltammetric studies showed the limit of detection down to 1 pg\/mL and a linear concentration range of 1\u2013100 pg\/mL with good sensitivity. Detection of CLU in spiked human plasma was demonstrated with satisfactory recovery percentages to that of the calibration data. The proposed method facilitates the cost-effective and viable production of label-free point-of-care devices for the clinical diagnosis of AD.<\/jats:p>","DOI":"10.3390\/s18010308","type":"journal-article","created":{"date-parts":[[2018,1,22]],"date-time":"2018-01-22T04:51:13Z","timestamp":1516596673000},"page":"308","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":37,"title":["Development of a Label-Free Immunosensor for Clusterin Detection as an Alzheimer\u2019s Biomarker"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8979-9899","authenticated-orcid":false,"given":"Kamrul","family":"Islam","sequence":"first","affiliation":[{"name":"Wolfson Nanomaterials &amp; Devices Laboratory, School of Computing, Electronics and Mathematics, Faculty of Science and Engineering, University of Plymouth, Devon PL4 8AA, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6747-0408","authenticated-orcid":false,"given":"Samar","family":"Damiati","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Faculty of Science, King Abdulaziz University (KAU), Jeddah 21589, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jagriti","family":"Sethi","sequence":"additional","affiliation":[{"name":"Wolfson Nanomaterials &amp; Devices Laboratory, School of Computing, Electronics and Mathematics, Faculty of Science and Engineering, University of Plymouth, Devon PL4 8AA, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ahmed","family":"Suhail","sequence":"additional","affiliation":[{"name":"Wolfson Nanomaterials &amp; Devices Laboratory, School of Computing, Electronics and Mathematics, Faculty of Science and Engineering, University of Plymouth, Devon PL4 8AA, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Genhua","family":"Pan","sequence":"additional","affiliation":[{"name":"Wolfson Nanomaterials &amp; Devices Laboratory, School of Computing, Electronics and Mathematics, Faculty of Science and Engineering, University of Plymouth, Devon PL4 8AA, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,1,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"523","DOI":"10.1139\/o94-070","article-title":"Expression of clusterin in cell differentiation and cell death","volume":"72","author":"Ahuja","year":"1994","journal-title":"Biochem. 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