Gene

Biology

Materials science

Peptide

Biochemistry

Molecule

Plasma protein binding

Stereochemistry

Combinatorial chemistry

Nanotechnology

Organic chemistry

Sequence (biology)

Molecular binding

Aqueous solution

Affinities

Rational design

Crystallography

Chemistry

Biophysics

Peptide sequence

Biomolecule

ACS Applied Materials & Interfaces

A major barrier to the systematic improvement of biomimetic peptide-mediated strategies for the controlled growth of inorganic nanomaterials in environmentally benign conditions lies in the lack of clear conceptual connections between the sequence of the peptide and its surface binding affinity, with binding being facilitated by noncovalent interactions. Peptide conformation, both in the adsorbed and in the nonadsorbed state, is the key relationship that connects peptide-materials binding with peptide sequence. Here, we combine experimental peptide-titania binding characterization with state-of-the-art conformational sampling via molecular simulations to elucidate these structure/binding relationships for two very different titania-binding peptide sequences. The two sequences (Ti-1, QPYLFATDSLIK; Ti-2, GHTHYHAVRTQT) differ in their overall hydropathy, yet via quartz-crystal microbalance measurements and predictions from molecular simulations, we show these sequences both support very similar, strong titania-binding affinities. Our molecular simulations reveal that the two sequences exhibit profoundly different modes of surface binding, with Ti-1 acting as an entropically driven binder while Ti-2 behaves as an enthalpically driven binder. The integrated approach presented here provides a rational basis for peptide sequence engineering to achieve the in situ growth and organization of titania nanostructures in aqueous media and for the design of sequences suitable for a range of technological applications that involve the interface between titania and biomolecules.

Aqueous Peptide–TiO<sub>2</sub> Interfaces: Isoenergetic Binding via Either Entropically or Enthalpically Driven Mechanisms

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

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