title: Sequence-Dependent Structural Stability of Self-Assembled Cylindrical Nanofibers by Peptide Amphiphiles.
abstract: Three-dimensional networks of nanofibers, which are formed through self-assembly of peptide amphiphiles, serve as a biomimetic hydrogel scaffold for tissue engineering. With an emphasis to improve hydrogel properties for cell-specific behavior, a better understanding between structural characteristics and physical properties of the macroscopic gel is sought. Large-scale molecular dynamics simulations were performed on two PA sequences with identical composition (palmitoyl-V3A3E3 and palmitoyl-A3V3E3) showing different self-assembly kinetic mechanisms. While both sequences yielded cylindrical nanofibers, these structures have contrasting internal arrangement with respect to the hydrophobic core; the former is continuous with predominately alkyl tails, whereas the latter is disjointed with interconnecting micelles. Two additional sequences (palmitoyl-V6E3 and palmitoyl-A6E3) were examined to determine the effects of a homogeneous β-sheet forming segment that is either strongly or mildly hydrophobic on self-assembly. Results from this study indicate that internal structural arrangement of nanofibers can provide a correlation with structural stability and mechanical behavior of hydrogel nanostructures.
authors.affiliation: Department of Chemical Engineering and Materials Science, University of California, Irvine, Irvine, California 92697, United States.
authors.forename: Iris W
authors.initials: IW
authors.lastname: Fu
authors.affiliation: Department of Chemical Engineering and Materials Science, University of California, Irvine, Irvine, California 92697, United States.
authors.forename: Hung D
authors.initials: HD
authors.lastname: Nguyen
mesh_terms: D000595:Amino Acid Sequence; D020100:Hydrogels / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D056004:Molecular Dynamics Simulation; D057139:Nanofibers / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*
chemical_list: D020100:Hydrogels; D010455:Peptides