In order to image localization of intracellular proteins with high specificity, it is frequently necessary to multiplex antibody probes conjugated to fluorescent markers. Today’s technology provides the researcher with a variety of immunofluorescent probes that can be combined in studies of cellular function. High-resolution, multi-probe imaging places a number of demands on imaging technologies; advanced CCD imaging solutions from QImaging are engineered to produce impressive results in this context.
Protocols for immunolabeling vary widely due to experimental goals. Interactions that contribute to antibody binding include hydrogen bonds, ionic bonds, hydrophobic interactions and van der Waals forces. The strength of each of these interactions is weak compared to a covalent bond.
Consequently, a large number of non-covalent interactions are required to stabilize antibody binding to an antigen. Each of these noncovalent interactions operates over a very small distance (1 Å or less) and so a strong antibody-antigen interaction depends on a very close fit between the antigen and antibody. This fit requires a high degree of complement between antigen and antibody. This requirement is the basis of the specificity that characterizes antigen-antibody interactions.