Immuno-surface fabrication for biosensor optimization

Experimental exploration and model development is being pursued for analytical determination of the best configuration and composition of immuno-surfaces for capturing target antigen. This study begins to investigate the influence of immuno-surface characteristics. Various surface chemistry fabrication techniques are compared for control of uniform-oriented antibody attachment to glass surfaces. Random orientation and non-specific attachment of antibody to the glass surface must be prevented to minimize surface heterogeneity and to maximize light-chain availability. Protein A is a binding protein that associates readily with IgG2a type antibody at the F_c region. Protein A is often used to attach antibodies and results in a surface-bound antibody that is oriented and functional with light chains free to bind antigen. This work has compared two surface chemistries, an aminosilane chemistry and a common heterobifunctional cross-linker (GMBS) technique, to evaluate their ability to covalently bind Protein A. In addition, various techniques for removing non-covalently bound protein from the glass surface were investigated and compared for effectiveness. In this manner, the present study demonstrated that GMBS covalently bound Protein A at higher densities than the aminophase technique.