Patterned and switchable surfaces for biomaterial applications

Chapter 1 - Introductionconsiderable role in regard to their behaviour at surfaces. For example, largermolecules tend to have a lower rate of surface adsorption when compared withsmaller molecules which adsorb, desorb and diffuse more readily from and to thesurface [9]. Both DNA and proteins have distinct characteristics that must beunderstood in order to effectively manipulate these molecules on surfaces. Cellsurfaceinteractions can also be controlled effectively via the control of biomoleculesurfaceinteractions since most cell-surface interactions are mediated by proteinadsorbed on surfaces.1.1.1. Principles of surface-biomolecular interactionsAlthough distinctive properties of specific biomolecules greatly influence theirsurface adsorption events, generally, hydrophobic interactions and the multivalenteffect are key factors that govern the adsorption behaviour of many biomolecules atsurfaces. Understanding these principles can concurrently lead to explanations ofbiomolecule-surface interactions.1.1.1.1. The hydrophobic interactionOne of the key interactions for all biomolecule surface adsorption is thehydrophobic interaction. This results when hydrophobic domains or moieties arepresent on both the surface and the biomolecule of interest. Thermodynamically, thedriving force for the adsorption of biomolecules through formation of hydrophobicinteractions is entropic gain due to the disordering of hydrophilic solvent moleculesthat must otherwise become ordered at a hydrophilic/hydrophobic interface. Thus,the solvent has a vital role in the formation of these interactions and in the presenceof a hydrophobic solvent, where there is no entropic gain in forming a hydrophobicinteraction, these interactions are strongly reduced [10]. In water, any biomolecules1-4