A Prediction Method for the Isoelectric Point of BinaryProtein Mixtures of Bovine Serum Albumin and LysozymeAdsorbed on Colloidal Titania and Alumina Particles
Bovine serum albumin and lysozyme mixtures of different mole fractions were adsorbed to colloidalalumina (116 nm) and titania particle (271 nm) suspensions of 2 vol % solid content for 16 h at pH 7.5.The total protein amount normalized to the powder surface area was 1000 ng/cm2. The zeta potential ofthe protein-treated suspensions was measured as a function of pH and the isoelectric point (IEP) obtained.A simple prediction model in two refinement steps was derived and evaluated for the obtained IEPs. Thebest model fit which takes into account moles of protein and surface fractions yielded an average predictionerror of 7.5% and a maximum error of 16.7%.