1 research outputs found
Subsurface Influence on the Structure of Protein Adsorbates as Revealed by in Situ X-ray Reflectivity
The adsorption process of proteins to surfaces is governed
by the
mutual interactions among proteins, the solution, and the substrate.
Interactions arising from the substrate are usually attributed to
the uppermost atomic layer. This actual surface defines the surface
chemistry and hence steric and electrostatic interactions. For a comprehensive
understanding, however, the interactions arising from the bulk material
also have to be considered. Our protein adsorption experiments with
globular proteins (α-amylase, bovine serum albumin, and lysozyme)
clearly reveal the influence of the subsurface material via van der
Waals forces. Here, a set of functionalized silicon wafers enables
a distinction between the effects of surface chemistry and the subsurface
composition of the substrate. Whereas the surface chemistry controls
whether the individual proteins are denatured, the strength of the
van der Waals forces affects the final layer density and hence the
adsorbed amount of proteins. The results imply that van der Waals
forces mainly influence surface processes, which govern the structure
formation of the protein adsorbates, such as surface diffusion and
spreading