Controlling interface properties: Formation and characterization of self-assembled monolayers

Self-assembled monolayer films of 11-hydroxyundecylphosphonate (HUPA) were deposited on oxide-covered Si coupons and were characterized by specular reflectance infrared spectroscopy (SRFTIR), atomic force microscopy (AFM), quartz crystal microgravimetry (QCM), cyclic voltammetry (CV), impedance spectroscopy, and X-ray photelecron spectroscopy (XPS). AFM and SRFTIR analysis revealed that the HUPA-based films are tightly packed and comprehensive, and that chemisorbtion likely proceeds through the formation of a phosphonate species. Electroanalytical investigation showed that the HUPA-modified Si surface is >99% covered, and that the films are stable under hydrolysis conditions. Characterization studies demonstrated that the HUPA-based SAM films are tightly packed and comprehensively cover the surface. The HUPA SAM films were used to anchor either Arg-Gly-Asp-Cys (RGDC) or an antibody. These modified films were placed in cell culture to assess their bioactivity. The RGDC terminated films greatly enhanced osteoblast cell adhesion and spreading on the modified surface, and the antibody terminated films displayed exquisite selectivity for cells expressing the antibody's corresponding antigen.; Surface passivation of tetragonal zirconia ceramic using SAM films deposited by three different methods were investigated for their ability to protect the ceramic from attack by water. Phosphonate films attached via a Zr alkoxide linker were found to be the most effective.