{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,19]],"date-time":"2026-10-19T17:00:42Z","timestamp":1792429242237,"version":"4.5.0"},"reference-count":32,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2022,11,21]],"date-time":"2022-11-21T00:00:00Z","timestamp":1668988800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biosensors"],"abstract":"<jats:p>Beta-amyloid (\u03b2A) peptides accompanying the physiological change in brain induce Alzheimer\u2019s disease. In this work, a highly sensitive electrochemical (EC) immunosensor platform has been developed for the quantitative detection of \u03b2A peptides, using the gold nanoparticle functionalized chitosan-aligned carbon nanotube (CS-aCNT-Au) nanocomposites on glassy carbon electrodes (GCE). The immunosensor has been fabricated by immobilization of the anti-\u03b2A antibody upon CS-aCNT-Au\/GCE. In the CS-aCNT nanocomposite, CS has high biocompatibility. Hydroxy and amine functionalities favor the antibody immobilization and prevent the leaching of nanocomposites of the modified electrode due to the adhesive environment. Moreover, aCNT offers high conductivity, stability, and a large surface area (the calculated effective surface area of the CS-aCNT\/GCE is 8.594 \u00d7 10\u22122 cm2). However, the incorporation of AuNPs further enhances the conductivity of the CS-aCNT-Au nanocomposite based on differential pulse voltammetry (DPV) results, and also improves the effective surface area (9.735 \u00d7 10\u22122 cm2). The surface morphology and electrochemical studies of the nanocomposite, as well as its modifications by the anti-\u03b2A antibody and BSA, were carried out through field emission scanning electron microscope (FESEM), cyclic voltammetry (CV), and DPV. The quantitative immunosensing of the \u03b2A in phosphate-buffered saline (PBS) solution is accomplished via DPV, which reveals that the immunosensor has a high sensitivity of 157.60 \u00b5A pg\u22121 mL cm\u22122 and a broad detection range of 10.0 pg mL\u22121\u2013100.0 \u00b5g mL\u22121, with a limit of detection (LOD) of 0.87 pg mL\u22121. Subsequently, we detected the spiked \u03b2A in diluted serum with a linear detection range of 10.0 pg mL\u22121\u20131.0 ng mL\u22121 and LOD of 0.95 pg mL\u22121. Moreover, a selectivity study exhibited a high affinity of immunosensors towards \u03b2A. Thus, we propose that this highly efficient immunosensor can potentially be applied for the point-of-care (POC) sensing of \u03b2A in clinical samples.<\/jats:p>","DOI":"10.3390\/bios12111059","type":"journal-article","created":{"date-parts":[[2022,11,22]],"date-time":"2022-11-22T02:59:22Z","timestamp":1669085962000},"page":"1059","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["Electrochemical Immunosensor for Early Detection of \u03b2-Amyloid Alzheimer\u2019s Disease Biomarker Based on Aligned Carbon Nanotubes Gold Nanocomposites"],"prefix":"10.3390","volume":"12","author":[{"given":"Pushpesh","family":"Ranjan","sequence":"first","affiliation":[{"name":"CSIR\u2014Advanced Materials and Processes Research Institute (AMPRI), Hoshangabad Road, Bhopal 462026, India"},{"name":"Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raju","family":"Khan","sequence":"additional","affiliation":[{"name":"CSIR\u2014Advanced Materials and Processes Research Institute (AMPRI), Hoshangabad Road, Bhopal 462026, India"},{"name":"Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Alzheimer\u2019s Association (2022). 2022 Alzheimer\u2019s Disease Facts and Figures. 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