Figure 2

Average second derivative spectra of the amide I region of (a) Aβ(1–40) and (b) Aβ(1–42) amyloid aggregates generated in vitro: fibrils (orange and blue respectively) generated at pH 7.4 and Aβ granular non-fibrillary aggregates (red and green respectively) generated at pH 5.5. The absorbance spectra were normalized for the amide I area prior to derivation. Origin 9.1 and Microsoft power point 2016 software were used for graphical representation.