Abstract
Self-assembling alkyl-peptides are important molecules due to their ability to construct nano-level structures such as nanofibers to be utilized as tissue engineering scaffolds. The bioactive epitope of FAQRVPP which acts as neural stem cells (NSCs) outgrowth inducing factor is used in nanofiber structures. Based on previous experimental studies the density and distribution pattern of the epitopes on the surface of the nanofibers plays an important role in the differentiation function efficiency. We decided to survey and compare the stability of two pre-constructed fiber structures in the forms of all-functionalized nanofiber (containing only bioactive alkyl-peptides) and distributed functionalized nanofiber (a combination of nonbioactive and bioactive alkyl-peptides with ratio 2:1). Our findings reveal that the all-functionalized fiber shows an unstable structure and is split into intermediate micelle-like structures to reduce compactness and steric hindrance of functional epitopes whereas the distributed functionalized fiber shows an integrated stable nanofiber with a more amount of beta sheets that are well-organized and oriented around the hydrophobic core. The hydrogen bonds and energy profiles of the structures indicate the role of hydrophobic interactions during the alkyl-chain core formation and the important role of electrostatic interactions and hydrogen bond network in the stability of the final structures. Finally, it seems that the possibility of the presence of intermediate structure is increased in the all-functionalized nanofiber environment, and it can reduce functional efficiency of the scaffolds. These findings can help to design more efficient nanofiber structures with different goals in scaffolds for tissue engineering.
Abbreviations | ||
MD | = | Molecular Dynamics |
NSCs | = | Neural Stem Cells |
PME | = | Particle mesh Ewald |
RDF | = | Radial Distribution Function |
RG | = | Radius of gyration |
RASA | = | Relative Accessible Surface Area |
RMSD | = | Root Mean Square Deviations |
SASA | = | Solvent Accessible Surface Area. |
Communicated by Ramaswamy H. Sarma
Disclosure statement
No potential conflict of interest was reported by the authors.
Supplementary material
The supplementary material for this article is available online at https://doi.org/10.1080/07391102.2018.1516571.