Fig. 7: FTIR spectroscopy coupled to PCA revealed the formation of diversified conformers in the presence of VQIVYK co-aggregating modifiers.

a Second derivatives of the FTIR spectra generated from mixed, peptide modifier-alone or VQIVYK-alone samples, focused around the amide I and amide II region (1700 cm⁻¹–1500 cm⁻¹). b PCA analysis of the derived spectra indicates the presence of different clustering locations in the eigen space representing the formation of differentiated amyloid fibril conformers in the different samples. For each sample, two individual preparations were split in two independent aliquots and combined in four data points (n = 4) per sample in order to represent the intrinsic variability in the spectral measurements.