TITLE:
Molecular Modeling of Cell Adhesion Peptides on Hydroxyapatite and TiO2 Surfaces: Implication in Biomedical Implant Devices
AUTHORS:
Subhashis Biswas, Udo Becker
KEYWORDS:
Hydroxyapatite; Nanobiomaterial; Bone-Tissue Engineering; RGD; TiO2
JOURNAL NAME:
Journal of Biomaterials and Nanobiotechnology,
Vol.4 No.4,
September
23,
2013
ABSTRACT:
Molecular
modeling as a tool in studying peptide-substrate interactions provides insight
on peptide adsorption conformation,
adsorption energy, and stability of the peptide-inorganic interface. This work
investigates the hydration and interaction of cell-adhesion peptides,
specifically RGD and YIGSR, with the hydroxyapatite surface and TiO2 surface in cluster and periodic boundary condition approaches. The comparison
of adsorption energies of RGD and YIGSR on both Hydroxyapatite (HA) and TiO2 surfaces reveals the similarities in
adsorption energy and orientation pattern of peptides on both surfaces. The models demonstrate that initial peptide
orientation affects adsorption energy for both. YIGSR is consistently more
strongly adsorbed to HA-(001) surfaces and steps than RGD for both the
surfaces. In addition, RGD maintained its
“hairpin”-like structure during adsorption on a flat HA-(001) surface, and a
slightly “relaxed hairpin” structure on TiO2 (110) surface.
Adsorption energies of RGD on TiO2 (110) surface are significantly more favorable compared to HA-(001) surface, suggesting potential role of TiO2 as biomedical implants when tissue regeneration occurs via cell signaling.