{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T22:16:58Z","timestamp":1792793818203,"version":"4.5.0"},"reference-count":53,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,8,21]],"date-time":"2025-08-21T00:00:00Z","timestamp":1755734400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100018990","name":"Alfaisal University","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100018990","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Neurosci."],"abstract":"<jats:p>Amyloid-\u03b2 (A\u03b2) is implicated in the pathophysiology of Alzheimer's disease (AD) and plays a significant role in neuronal degeneration. A\u03b2 in solution is essential during the initial stages of developing lead compounds that influence A\u03b2 fibrillation. The tendency of the A\u03b2 peptide to misfold in solution is correlated with the etiology of AD. Therefore, the early detection of A\u03b2 serves as a critical foundation for diagnostic testing and routine clinical assessment of AD. Herein, an aggregation-induced fluorescence probe, triphenylamine rhodamine-3-acetic acid (mRA), was used to detect A\u03b2 aggregates. The fluorescence results showed a strong interaction between the fluorescence probe mRA and A\u03b2 aggregates. mRA specifically binds with high affinity to A\u03b2 aggregates, and the limit of detection (LOD) of A\u03b2 aggregates was 0.12 \u03bcg\/mL. Molecular docking studies showed that the mRA has significant binding affinity toward the A\u03b2 peptide at the N\/C-terminal region, with a binding energy of \u22126.5 kcal\/mol. Furthermore, CD studies confirmed that the mRA binds to A\u03b2 aggregates, and its binding induces significant structural alteration of the A\u03b2 aggregates. Thermodynamic properties revealed that the binding of A\u03b2 aggregates to mRA is a spontaneous process, driven by enthalpy and favored by entropy, which helps further our understanding of the interaction between mRA and A\u03b2 aggregates at the molecular level. The negative \u0394H suggests that hydrogen bonding is a dominant force for the mRA interaction with A\u03b2 aggregates. This study provides a rationale for using mRA as a biosensor for the detection of A\u03b2 aggregates in biological fluids, offering a potential tool for the early diagnosis and monitoring of amyloid progression in AD.<\/jats:p>","DOI":"10.3389\/fnins.2025.1653063","type":"journal-article","created":{"date-parts":[[2025,8,21]],"date-time":"2025-08-21T05:28:02Z","timestamp":1755754082000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":8,"title":["A novel fluorescent probe, triphenylamine rhodamine-3-acetic acid (mRA) for the detection of Amyloid-\u03b2 aggregates in Alzheimer's disease"],"prefix":"10.3389","volume":"19","author":[{"given":"Raja","family":"Chinnappan","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mateen A.","family":"Khan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Taj","family":"Mohammad","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah Mohammed","family":"Allwaibh","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shanmugam","family":"Easwaramoorthi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ahmed","family":"Yaqinuddin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sandhanasamy","family":"Devansan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tanveer Ahmad","family":"Mir","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Imtaiyaz","family":"Hassan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2025,8,21]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"239","DOI":"10.1016\/j.bioactmat.2021.10.047","article-title":"Picomolar-sensitive \u03b2-amyloid fibril fluorophores by tailoring the hydrophobicity of biannulated \u03c0-elongated dioxaborine-dyes","volume":"13","author":"An","year":"2022","journal-title":"Bioact. 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