Parallel β-sheet fibrils were also prepared from Aβ 25-35 peptide. This was accomplished by dissolving 2.12 mg of peptide in 1.06 mL of water. The resulting peptide solution appeared visually clear. After this, 1.06 mL of 2× phosphate buffer saline (PBS, pH 7.4) was slowly added to the sample for a final peptide concentration of 1 mM. The solution was gently mixed by carefully inverting the sample vial 3 times. Aggregates could be visually observed shortly after preparing the solution and was incubated at 37 °C for 3 days.