Protein adsorption on to low-temperature isotropic carbon 4. Competitive adsorption on carbon and silica studied by two-dimensional electrophoresis

Abstract

Two-dimensional polyacrylamide gel electrophoresis (2D PAGE) was applied to the study of competitive protein adsorption from diluted human plasma. We obtained the depletion (adsorption) of some 25 plasma proteins in the presence of low-temperature isotropic carbon (LTIC) or silica powders. The depletion data are used as a measure of protein adsorptivity. Generally, proteins of lowest abundance have the highest tendency to associate with the two solid surfaces studied. The adsorptivity of a protein is largely determined by its solubility. Most proteins detected exhibit similar depletion behavior on both adsorbents, suggesting a multilayer adsorption process. Three proteins, hemopexin, apolipoprotein A I, and apolipoprotein A II, are depleted differently in the presence of LTIC and silica powders.