Following incubation, fibrils were harvested from each sample by centrifuging 500 µL of solutions for 1 h at 21300×g (Eppendorf Centrifuge 5425). The supernatant for each sample was carefully decanted so that the pellet remained. The pellet was washed twice to remove residual salt crystals by sequentially resuspending it in water and centrifuging. Following this, the pellet was resuspended in 250 µL of water. Aliquots of each sample were then diluted, deposited onto a silicon substrate, and allowed to dry in a dust free environment to create a coffee ring for polarized Raman measurements.