Dynamic light scattering (DLS)

Peptide stock solutions were prepared at 800 µM in PBS with 5% v/v DMSO. These were subjected to centrifugation at 2000 × g for 5 min at 20 °C (Eppendorf 5810 R; Eppendorf, Germany) to remove dust and excessively large aggregates. 150 µl of the supernatant was transferred to a quartz cuvette and the particle size distribution at 20 °C was determined using DLS (Zetasizer NanoS; Malvern Instruments Ltd. Malvern, UK.). The number distribution (number of aggregates observed per aggregate diameter) from two independent experiments with three technical replicates each was then used to determine the mean aggregate size of each peptide across the 12 replicates. Aggregates were then categorised into three classes, those producing small aggregates (<10 nm diameter), moderate aggregates (diameter between 10 and 10⁴ nm) or large aggregates (>10⁴ nm diameter).