Data set for the Commun. Chem. article by Paul et al. with the title "13C- and 15N-labeling of amyloid-β and inhibitory polypeptides to study their interaction via nanoscale infrared spectroscopy" doi-10-17045-sthlmuni-23609580-0 https://doi.org/10.17045/STHLMUNI.23609580 Swedish National Data Service Svensk nationell datatjänst Landing page Data set for the Commun. Chem. article by Paul et al. with the title "13C- and 15N-labeling of amyloid-β and inhibitory polypeptides to study their interaction via nanoscale infrared spectroscopy" doi-10-17045-sthlmuni-23609580-0 https://doi.org/10.17045/STHLMUNI.23609580 Barth, Andreas Swedish National Data Service Svensk nationell datatjänst Landing page The data published here are the basis for the article by Paul et al. in Commun. Chem. with the title 13C- and 15N-labeling of amyloid-β and inhibitory polypeptides to study their interaction via nanoscale infrared spectroscopy and for the Research Square preprint by Paul et al. with DOI: 10.21203/rs.3.rs-2141341/v1 (https://doi.org/10.21203/rs.3.rs-2141341/v1) and title 13C-isotope-editing of nanoscale infrared images reveals the action of an inhibi­tory peptide against amyloid-β aggregation.   These publications show that 13C, 15N-labeling can be used to discriminate between two peptides in nanoscale images of their infrared absorption, even when they have similar secondary structure. We studied different aggregation states of the amyloid-β peptide (Aβ) and its interaction with an inhibitory cell-penetrating peptide (NCAM1-PrP) using scattering-type scanning near-field optical microscopy (s-SNOM). Labeled and unlabeled peptides could be distinguished by comparing images of the optical phase taken at wavenumbers characteristic for either the labeled or the unlabeled peptide. Some of the provided files require particular software to view them: Gwyddion (http://gwyddion.net/) is needed for image files, neaPLOT (attocube) for nano-FTIR spectra, and OPUS (Bruker) for FTIR spectra. Processed neaPLOT files were stored as csv files. OPUS files were converted to txt files but can also be read by Spectragryph (https://www.effemm2.de/spectragryph/about.html), which is free for private and academic use. Access to data through an external actor. Åtkomst till data via extern aktör.