{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T13:34:46Z","timestamp":1790688886163,"version":"4.1.0"},"reference-count":38,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2025,12,10]],"date-time":"2025-12-10T00:00:00Z","timestamp":1765324800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Republic of T\u00fcrkiye Ministry of National Education","award":["1416"],"award-info":[{"award-number":["1416"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biosensors"],"abstract":"<jats:p>Alzheimer\u2019s Disease (AD) is one of the most commonly seen neurodegenerative disorders, where early detection of its biomarkers is crucial for effective management. Conventional diagnostic methods are often expensive, time-consuming, and highly complex, which highlights an urgent need for point-of-care biosensing technology. In this work, we developed assays on three-dimensional (3D) graphene foam electrodes by functionalising them with a 1-Pyrenebutyric acid N-hydroxysuccinimide ester (Pyr-NHS) to enable effective antibody immobilisation for the detection of amyloid beta peptides (A\u03b242 and A\u03b240), key biomarkers for AD. Pyr-NHS linkers were used for stable functionalisation, followed by binding with A\u03b242 and A\u03b240 antibodies, and then bovine serum albumin (BSA) was employed as a blocking agent to minimise non-specific bindings on the electrode surface. Differential Pulse Voltammetry (DPV) measurements showed satisfactory stability over 12 days (RDS upper limit was &lt;10%) and highly sensitive and specific detection of A\u03b242 and A\u03b240, with insignificant interference of tau217 protein. The biosensor exhibited a low limit of detection (LOD) with 252 aM for A\u03b242 and 395 aM for A\u03b240, covering 0.125 fM\u20131 nM and 0.125 fM\u2013100 pM linear ranges, respectively. Further validation was conducted on spiked-diluted human plasma. This excellent analytical performance was attributed to the stable Pyr-NHS functionalisation, the 3D graphene foam enabling superior conductivity and a larger surface area on the working electrode, and the optimisation of antibody concentration for immobilisation. These promising results suggest that 3D graphene foam-based biosensors have considerable potential for early detection of AD biomarkers and developing cost-effective, portable, and reliable point-of-care devices.<\/jats:p>","DOI":"10.3390\/bios15120806","type":"journal-article","created":{"date-parts":[[2025,12,10]],"date-time":"2025-12-10T16:11:18Z","timestamp":1765383078000},"page":"806","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Electrochemical Detection of A\u03b242 and A\u03b240 at Attomolar Scale via Optimised Antibody Loading on Pyr-NHS-Functionalised 3D Graphene Foam Electrodes"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-5564-4019","authenticated-orcid":false,"given":"Muhsin","family":"Dogan","sequence":"first","affiliation":[{"name":"Nanomaterials and Devices Laboratory (NMD), School of Engineering, Computing and Mathematics, University of Plymouth, Devon PL4 8AA, UK"},{"name":"Biomedical Engineering, Engineering and Architecture Faculty, Izmir Bakircay University, Izmir 35665, Turkey"},{"name":"School of Engineering, Computing and Mathematics, University of Plymouth, Devon PL4 8AA, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9460-3627","authenticated-orcid":false,"given":"Sophia","family":"Nazir","sequence":"additional","affiliation":[{"name":"Nanomaterials and Devices Laboratory (NMD), School of Engineering, Computing and Mathematics, University of Plymouth, Devon PL4 8AA, UK"},{"name":"School of Engineering, Computing and Mathematics, University of Plymouth, Devon PL4 8AA, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7471-1743","authenticated-orcid":false,"given":"David","family":"Jenkins","sequence":"additional","affiliation":[{"name":"Nanomaterials and Devices Laboratory (NMD), School of Engineering, Computing and Mathematics, University of Plymouth, Devon PL4 8AA, UK"},{"name":"School of Engineering, Computing and Mathematics, University of Plymouth, Devon PL4 8AA, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yinghui","family":"Wei","sequence":"additional","affiliation":[{"name":"School of Engineering, Computing and Mathematics, University of Plymouth, Devon PL4 8AA, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Genhua","family":"Pan","sequence":"additional","affiliation":[{"name":"Nanomaterials and Devices Laboratory (NMD), School of Engineering, Computing and Mathematics, University of Plymouth, Devon PL4 8AA, UK"},{"name":"School of Engineering, Computing and Mathematics, University of Plymouth, Devon PL4 8AA, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,10]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2024). 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