The smaller ions (F- and Cl-, 50mM NaF and NaCl solutions) tend to stabilize β-sheets
Peptide amphiphiles are composed of hydrophobic alkyl tails and peptide regions designed to self-assemble into cylindrical supramolecular nanofibers in solution. While some β-sheets are formed by hydrogen bonds between short β-strands (2 or 3 residues) others are formed by extended -strands.