Peptide Amphiphile Nanofiber Self-Assembly

Peptide amphiphiles — short peptides fused to a hydrophobic tail — spontaneously self-assemble in water into long cylindrical nanofibers used as scaffolds in regenerative-medicine and drug-delivery biomaterials. This simulator models the three forces that drive that process at the coarse-grained level: hydrophobic burial of the alkyl tails (a Lennard-Jones attraction), Debye-screened electrostatic repulsion between charged headgroups that keeps the aggregate thin instead of collapsing into a droplet, and a nematic alignment term standing in for the directional hydrogen bonding that locks peptide backbones into a shared β-sheet register along the fiber axis. Adjust monomer concentration relative to the critical aggregation concentration, ionic strength (which screens headgroup charge), temperature (thermal disruption) and β-sheet propensity, and watch nanofibers nucleate, elongate or fall apart in real time while nematic order, assembled fraction and longest-fiber length are tracked live.