From biominerals to biomaterials: the role of biomolecule–mineral interactions

Abstract

Interactions between inorganic materials and biomolecules at the molecular level, although complex, are commonplace. Examples include biominerals, which are, in most cases, facilitated by and in contact with biomolecules; implantable biomaterials; and food and drug handling. The effectiveness of these functional materials is dependent on the interfacial properties, i.e. the extent of molecular level 'association' with biomolecules. The present article gives information on biomolecule-inorganic material interactions and illustrates our current understanding using selected examples. The examples include (i) mechanism of biointegration: the role of surface chemistry and protein adsorption, (ii) towards improved aluminium-containing materials, and (iii) understanding the bioinorganic interface: experiment and modelling. A wide range of experimental techniques (microscopic, spectroscopic, particle sizing, thermal methods and solution methods) are used by the research group to study interactions between (bio)molecules and molecular and colloidal species that are coupled with computational simulation studies to gain as much information as possible on the molecular-scale interactions. Our goal is to uncover the mechanisms underpinning any interactions and to identify 'rules' or 'guiding principles' that could be used to explain and hence predict behaviour for a wide range of (bio)molecule-mineral systems.

Thermodynamic Study of Interactions Between ZnO and ZnO Binding Peptides Using Isothermal Titration Calorimetry

“…From estimation of the size of peptide molecules using molecular dynamics (MD) software, the theoretical maximum number of peptide molecules needed to form monolayer coverage (assuming that the peptides adsorbed to the ZnO surfaces end-on/upright for maximum possible monolayer coverage) on the total surface area of ZnO rods present in an ITC experiment (based on BET analysis), was less than the amount of peptide experimentally needed to attain saturation in ITC experiments. For example, the number of unit molecules of G-12 estimated to fill a monolayer was 8.91 x 10 13 and the amount needed to reach saturation in ITC experiments was 2.46 x 10 17 . In all the interactions, the amount of peptide needed to obtain saturation was in great excess of the amount required to form monolayer coverage suggesting that dense peptide multilayers were formed on ZnO.…”

“…Therefore, understanding the energetic changes that occur during peptide-inorganic interactions and correlating these to structural modifications of the inorganic materials could be the key to advancing material synthesis/design and may also reveal key principles through which material structure is controlled in nature. [15][16][17] Of specific interest, in-house studies have been carried out to understand the fundamental principles through which ZnO binding peptides (ZnO-BPs) interact with and modify ZnO growth process and morphology. 6,8,18 In a recent contribution, the mechanisms through which specific ZnO binding peptides (ZnO-BPs) interact with and modify the growth process and morphology of ZnO during solution synthesis was described.…”

Prediction of Specific Biomolecule Adsorption on Silica Surfaces as a Function of pH and Particle Size

“…For example, efforts to synthesize silica from precursors to replicate hierarchically organized silica-protein skeletons similar to diatoms, marine organisms, 5,11,12 and plants have shown first successes in achievable structural order. 7,9,[13][14][15][16][17] However, fundamental insight into mechanisms and control of assembly remains incomplete even though many amino acid sequences, peptides and proteins from microorganisms, cellular templates, and designed ligands were tested. 6-10, 14, 18 Therefore, better understanding of the role of the precursors, of the surface chemistry of silica formed, as well as of the competitive interactions with solvents and proteins could provide significant benefits to the rational engineering of silica-based materials.…”

Biomimetic Protamine-Templated Silicification

“…21 The adhesion must be rapid, strong, tough, and the thickness of the adhesion layer is usually within several to tens of nanometers. Inspired by the bioadhesion phenomenon and the composition of adhesive proteins in mussels, Messsersmith 52 found that dopamine could form multifunctional polymer coatings through a simple dip-coating of objects in an aqueous solution under mild conditions.…”