2005 Volume 3 Pages 173-178
The adsorption of the plasma protein fibrinogen on model hydrophobic surfaces has been explored using atomic force microscopy. Images of fibrinogen adsorbed on both graphite and methyl-terminated self-assembled monolayers are both observed to be highly non-uniform. On both substrates, aggregation and clustering of the fibrinogen molecules is seen. In the case of the graphite surface, we observe a strong preference for adsorption at atomic level steps in the graphite structure. In addition, a region free of protein adsorption is often observed near the step edges. Based on the size of this protein-depleted region, we estimate that the fibrinogen molecules must have diffusion lengths on the order of ∼200 nm under the conditions of these experiments. These results suggest that in the initial stages of adsorption, fibrinogen is quite mobile on a hydrophobic surface. [DOI: 10.1380/ejssnt.2005.173]
