Effects of fluid shear and temperature on protein adsorption on teflon surfaces

Partial gold decoration TEM images of protein adsorption on Teflon have been reliably obtained and confirmed by independent imaging methods. Albumin deposits are irregular in shape, unconnected, with low surface coverage in the range of 25-2500 mg/dl. The deposits tend to follow surface structural details to a scale of 4000A. In contrast, Cohn I fibrinogen deposits are reticulated, connected, with high surface coverage, which do not reflect details of surface structure, in the range of 3-300 mg/dl. The albumin adsorbates decrease with increasing wall shear rate and have negligible temperature dependence. The Cohn I fibrinogen adsorbates are not shear dependent, up to 800 sec-1, nor are they temperature dependent from 20-40 degrees C. These results support the view that nondenatured albumin maintains weak protein-polymer and protein-protein bonds, whereas Cohn I fibrinogen adsorbates are fostered by strong protein-protein interactions.