In this study, the effect of silanol density on the interaction of fibrinogen at physiological concentrations with silica nanoparticle/flat surfaces has been studied.
Silica nanoparticles and silica wafers were modified and characterized to obtain a set of samples with different silanols density. The interaction with fibrinogen has been studied by evaluating the extent of coverage (bicinchoninic acid assay) and the irreversibility of adsorption (shift of the 味 potential). To clarify the molecular mechanism of fibrinogen/surface interactions, confocal micro-Raman spectroscopy (nanoparticles) and atomic force microscopy (wafers) were used. Finally the effect of fibrinogen on the agglomeration of nanoparticles has been evaluated by Flow Particle Image Analysis.
The data reported here show that a minimal variation in the state of the silica surface modifies the adsorption behavior of fibrinogen, which appears mediated by a competition between protein/protein and protein/surface interactions. By comparing the data obtained on nanoparticles and silicon-supported silica layers, we found that hydrophilicity increases the tendency of fibrinogen molecules to interact with the surface rather than with other molecules, thus inhibiting fibrinogen self-assembly.
This study contributes to the knowledge of the processes occurring at the surface/biological fluids interface, needed for the design of new biocompatible materials.