In situ Atomic Force Microscope observation of self-assembly adsorption of Bovine Serum Albumin on silica and gold nano film

The self-assembly adsorption of bovine serum albumin (BSA) on the hybrid surface including the discontinuous gold nano film and silica under liquid condition was studied in situ by atomic force microscope (AFM) at room temperature. To investigate the adsorption of BSA on silica and gold nano film simultaneously, the surface with discontinuous gold nano film and visible blank block on silica by physical vapor deposition (PVD) and the ultrasonic cleaning technology was fabricated. Then we observed the variation on the substrate surface before and after injecting BSA aqueous solution with a 0.05 mg/ml concentration at real time by AFM. The experimental results indicated that the adsorption strength of BSA on the surface of gold nano film is larger than that on silica surface, and further implied that the adsorption capability of the hydrophobic surface is larger than that of the hydrophilic, which is consistent with those reported. Moreover, it could be easily observed that the adsorption of BSA on gold nano film has great tendency to form a ridgeway-like topography.