The surface activity of α-lactalbumin, β-lactoglobulin, and bovine serum albumin: II. Some molecular influences on adsorption to hydrophilic and hydrophobic silicon surfaces

摘要: Abstract The thermal transitions experienced by α-lactalbumin (α-Lac), β-lactoglobulin (β-Lg), and bovine serum albumin (BSA) during a temperature ramp from 15 to 160°C were evaluated with differential scanning calorimetry. Adsorption isotherms then constructed for each protein on hydrophilic hydrophobic silicon surfaces at 2, 27, 52°C. α-Lac exhibited more or less steady increase in adsorption surface, the adsorbed mass beyond 27°C being consistent an transition occurring facilitate favorable noncovalent contacts surface. Isotherms 27 52°C similar both β-Lg BSA, which do not undergo thermally induced until onset temperatures of about 64.0 54.4°C are reached, respectively. For protein, was depressed 2°C, decreasing stabilization interactions strengthening hydrogen bonds cold. Although observed correlate reasonably well molecular size temperature, isotherm data thought provide only indication surface influences relative amounts single-component affinities; i.e., effects simply incidental, proteins low stability and/or high flexibility preferentially adsorbed.