Modeling the Interaction of L-Hydroxyproline, a Constituent of Collagen, with a Hydrated TiO₂ Lattice at Varied Concentrations: Examining Surface and Long-Range Effects

This study investigates the interaction between l-hydroxyproline (LHP), a key component of collagen, and a hydrated titanium dioxide (TiO₂) lattice at various LHP concentrations. We performed gas chromatography–mass spectrometry analysis of byssus, which revealed 22 metabolites, confirming glycine, l-proline, and particularly LHP as key biomolecules. Subsequently, molecular dynamics (MD) simulations provided insights into LHP-lattice interaction mechanisms, revealing the TiO₂ lattice’s ability to align LHP rings near-perpendicular to the lattice surface and near-parallel to each other, facilitated by the LHP tail functional group. This indicates optimal LHP packing, particularly close to the surface, and the formation of durable bonds between LHPs and lattice atoms. The analysis, particularly radial distribution functions, indicates that lattice-driven organizing interactions extend from the surface region to the bulk liquid phase thanks to the LHP- and water-mediated contributions. Overall, the simulation provides a chemical-physics rationale to explain improved collagen adhesion to the TiO₂ lattice and the mechanical strength of collagen threads, contributing to understanding collagen-TiO₂ interactions and offering valuable insights for nanomaterials, biomaterials, tissue engineering, and biomedical applications.