{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T13:29:02Z","timestamp":1790861342591,"version":"4.1.0"},"reference-count":34,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,6,24]],"date-time":"2020-06-24T00:00:00Z","timestamp":1592956800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Amyloid fibrils are composed of aggregated peptides or proteins in a fibrillar structure with a higher \u03b2-sheet content than in their native structure. To characterize them, we used an innovative tool that coupled infrared spectroscopy with atomic force microscopy (AFM-IR). With this method, we show that we can detect different individual aggregated species from oligomers to fibrils and study their morphologies by AFM and their secondary structures based on their IR spectra. AFM-IR overcomes the weak spatial resolution of usual infrared spectroscopy and achieves a resolution of ten nanometers, the size of isolated fibrils. We characterized oligomers, amyloid fibrils of A\u03b242 and fibrils of \u03b1-synuclein. To our surprise, we figured out that the nature of some surfaces (ZnSe) used to study the samples induces destructuring of amyloid samples, leading to amorphous aggregates. We strongly suggest taking this into consideration in future experiments with amyloid fibrils. More importantly, we demonstrate the advantages of AFM-IR, with a high spatial resolution (\u2264 10 nm) allowing spectrum recording on individual aggregated supramolecular entities selected thanks to the AFM images or on thin layers of proteins.<\/jats:p>","DOI":"10.3390\/molecules25122899","type":"journal-article","created":{"date-parts":[[2020,6,24]],"date-time":"2020-06-24T10:54:59Z","timestamp":1592996099000},"page":"2899","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":42,"title":["Characterization by Nano-Infrared Spectroscopy of Individual Aggregated Species of Amyloid Proteins"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3964-2986","authenticated-orcid":false,"given":"Jehan","family":"Waeytens","sequence":"first","affiliation":[{"name":"Structure et Fonction des Membranes Biologiques, Universit\u00e9 libre de Bruxelles, B-1050 Bruxelles, Belgique"},{"name":"Laboratoire de Chimie Physique d\u2019Orsay, CNRS UMR8000, Universit\u00e9 Paris-Sud, Universit\u00e9 Paris-Saclay, F-91400 Orsay, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vincent","family":"Van Hemelryck","sequence":"additional","affiliation":[{"name":"Spectralys Biotech, Universit\u00e9 libre de Bruxelles, B-1050 Bruxelles, Belgique"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ariane","family":"Deniset-Besseau","sequence":"additional","affiliation":[{"name":"Laboratoire de Chimie Physique d\u2019Orsay, CNRS UMR8000, Universit\u00e9 Paris-Sud, Universit\u00e9 Paris-Saclay, F-91400 Orsay, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jean-Marie","family":"Ruysschaert","sequence":"additional","affiliation":[{"name":"Structure et Fonction des Membranes Biologiques, Universit\u00e9 libre de Bruxelles, B-1050 Bruxelles, Belgique"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandre","family":"Dazzi","sequence":"additional","affiliation":[{"name":"Laboratoire de Chimie Physique d\u2019Orsay, CNRS UMR8000, Universit\u00e9 Paris-Sud, Universit\u00e9 Paris-Saclay, F-91400 Orsay, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7507-1845","authenticated-orcid":false,"given":"Vincent","family":"Raussens","sequence":"additional","affiliation":[{"name":"Structure et Fonction des Membranes Biologiques, Universit\u00e9 libre de Bruxelles, B-1050 Bruxelles, Belgique"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,24]]},"reference":[{"key":"ref_1","unstructured":"Alzheimer\u2019s Disease International (2019). 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