Adsorption of collagen nanofibrils on rough TiO 2: A molecular dynamics study

TitleAdsorption of collagen nanofibrils on rough TiO 2: A molecular dynamics study
Publication TypeJournal Article
Year of Publication2011
AuthorsFriedrichs, W, Ohler, B, Langel, W, Monti, S, Köppen, S
JournalAdvanced Engineering Materials
ISSN14381656 (ISSN)
KeywordsAdsorption, C-terminus, Classical molecular dynamics, Collagen, Collagen molecules, Helix binding, Microfacets, molecular dynamics, Nano-fibrils, Oxide minerals, Steric hindrances, Surface adsorption, Surface models, Surface roughness, TiO, Titania surfaces, Titanium dioxide, Triple helical structures, Triple helixes, Triple-helices

Classical molecular dynamics simulations of tropocollagen molecules on rough titania surfaces are presented. On the basis of plane rutile (100), two models for surface roughness have been adopted: (1 × 3) microfacets with dimensions of less than 14 \AA had only minor influence on the adsorption of a triple helical structure with a diameter of about 16 \AA. After increasing the roughness by terraces, steric hindrance of helix binding was observed. A model for telopeptide capping of the collagen triple helices was developed. The highly flexible telopeptide structures mediated adsorption on the surface and inserted into grooves of both surface models. The telopeptide $\beta$-turn motifs at the C-terminus of the tropocollagen interact with specific receptor regions of the triple helices. This intermolecular process seems to be entropy driven and may be the first step of assembling helices to ordered fibrils. Interaction between telopeptide and triple helix seems to be in competition with the rather enthalpy controlled surface adsorption of single collagen molecules. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.