Perkin elmer spectrum two ir spectrometer

To assess secondary structure formation, transition intensities and vibrational frequencies, a PerkinElmer Spectrum Two IR spectrometer (PerkinElmer Ltd, Beaconsfield, United Kingdom) equipped with a PerkinElmer single-reflection diamond ATR was used. All samples were measured in the wavelength range between 400-4000 cm -1 at room temperature, after dissolution in water at the respective working concentration, and with the addition of DPBS above the ATRdiamond to investigate the presence of amides I and II. ATR-FTIR spectra were analyzed with OriginPro 2019 software (OriginLab Corporation, Northampton, MA, USA) after baseline correction. Deconvolution of ATR-FTIR absorption spectra was performed by using the second derivative method followed by smoothing with a 7-9 point Savitsky-Golay function ( polynomial order of 2). Peak fitting/deconvolution was obtained with the Voigt function from OriginPro. 87 Paper Nanoscale Preparation of Thioflavin-T assay and fluorescence measurement
All peptides were with a solution the benzothiol dye ThT previously dissolved in buffer and mixed in a ThT/ peptide ratio of 0.5 : 1. For the detection of β-sheets, the ThT fluorescence was measured at room temperature, right after the reaction, using an Infinite M200 Pro plate reader (Tecan, Mennedorf, Switzerland) with excitation at 440 nm and emission at 482 nm.