Aqueous Peptide-TiO2 Interfaces: Isoenergetic Binding via Either Entropically or Enthalpically Driven Mechanisms

Area of Science:

• Biomimetic materials science
• Nanomaterial synthesis
• Peptide-surface interactions

Background:

• Improving biomimetic peptide strategies for nanomaterial growth requires understanding peptide sequence-binding relationships.
• Peptide conformation is crucial for connecting peptide sequence to material binding affinity.

Purpose of the Study:

• To elucidate structure/binding relationships for titania-binding peptides.
• To provide a rational basis for engineering peptide sequences for controlled nanomaterial growth.

Main Methods:

• Experimental peptide-titania binding characterization using quartz-crystal microbalance.
• Conformational sampling via molecular simulations.
• Analysis of peptide sequences Ti-1 (QPYLFATDSLIK) and Ti-2 (GHTHYHAVRTQT).

Main Results:

• Both Ti-1 and Ti-2 peptides exhibit strong titania-binding affinities, despite differing hydropathy.
• Molecular simulations reveal distinct binding modes: Ti-1 is entropically driven, Ti-2 is enthalpically driven.
• Identified clear structure/binding relationships for titania-binding peptides.

Conclusions:

• The integrated experimental and computational approach provides a rational basis for peptide sequence engineering.
• Enables in situ growth and organization of titania nanostructures in aqueous media.
• Facilitates design of peptides for applications involving titania-biomolecule interfaces.