Adsorption of Milk Proteins (β-Casein and β-Lactoglobulin) and BSA onto Hydrophobic Surfaces

Abstract

Here, we study films of proteins over planar surfaces and protein-coated microspheres obtained from the adsorption of three different proteins (β-casein, β-lactoglobulin and bovine serum albumin (BSA)). The investigation of protein films in planar surfaces is performed by combining quartz crystal microbalance (QCM) and atomic force microscopy (AFM) measurements with all-atomic molecular dynamics (MD) simulations. We found that BSA and β-lactoglobulin form compact monolayers, almost without interstices between the proteins. However, β-casein adsorbs forming multilayers. The study of the electrokinetic mobility of protein-coated latex microspheres shows substantial condensation of ions from the buffer over the complexes, as predicted from ion condensation theories. The electrokinetic behavior of the latex-protein complexes is dominated by the charge of the proteins and the phenomenon of ion condensation, whereas the charge of the latex colloids plays only a minor role.

Friction between soft contacts at nanoscale on uncoated and protein-coated surfaces

“…The size of the globular structures is in agreement with the dimensions of β-lg on hydrophobic (methyl-terminated) SAMs surfaces. 57 In contrast to LF, the surface charge of β-lg is more evenly distributed on its surface, although there is still a small negative patch. 73 However, looking at the hydrophobicity, β-lg has a large hydrophobic patch on one side that could lead to strong adsorption on the PDMS surface (Fig.…”

Bio-interfactants as double-sided tapes for graphene oxide

“…76 Considering these facts and that GO is negatively charged at our experiment pH, it is expected that laccase would be less prone to bind to GO than BSA, in which the arginine, lysine and histidine anchoring sites are more uniformly distributed over all the protein's surface. 77,78 Moreover, hydrophobic BSA/ GO interactions may provide an additional driving force towards surface binding. 79 The topography of the thermally reduced coatings, in particular the distinct rippling details, can be further examined in profiles of height and phase changes in selected areas of the AFM images (Fig.…”

Protein-surface interactions at the nanoscale: Atomistic simulations with implicit solvent models

“…Using these models, it has been possible to investigate with atomistic detail many interesting processes such as the structure of protein corona of a NP [14,9] or how proteins adsorbed onto a surface respond to a pH change [15], among others, as we will see. Our objective in this article will be to summarize these developments.…”