Protein adsorptive behavior on mesoporous titanium dioxide determined by geometrical topography.

This work develops a linearly predictive model that investigates the relationship between the geometrical topography of mesoporous titanium dioxide (TiO2) and protein adsorption at the isoelectric point. Proteins with different sizes, Bovine Serum Albumin, Myoglobin and Lysozyme, were employed as model molecules to analyze proein-TiO2 interactions. Mesoporous TiO2 surfaces with a range of pore sizes served as a model of topography were utilized as substrates to study the effects of topography on protein adsorption. By fitting the amount of adsorbed proteins to the varying geometrical topographies, a linear relationship was obtained to estimate the protein-surface interaction. It was found that the three proteins avidly adsorb on TiO2 surface with strengthening coupling geometrical effects. The interaction between proteins and mesoporous TiO2 with varying geometrical topographies was further examined by the adhesive force measurements via atomic force microscopy (AFM). The adsorption of protein Chicken Ovalbumin confirmed that the linear curve, describing protein-surface interaction, could be used as a general tool to predict protein adsorption at the isoelectric point. Furthermore, High-Performance Liquid Chromatography (HPLC) results at the macro-scale also demonstrated the accuracy of the predictive adsorption model. According to this model, TiO2 surfaces with well-designed geometrical topographies can be constructed efficiently and expected for various applications such as fouling resistance, proteins separation and immobilization. [ABSTRACT FROM AUTHOR]