Redox-Immunofunctionalized Potyvirus Nanoparticles for High-Resolution Imaging by AFM-SECM Correlative Microscopy

We present in this chapter a new experimental approach allowing the high resolution imaging of immune complexes on virus particles. Combined atomic force-electrochemical microscopy (AFM-SECM) is used to image the presence of ferrocene functionalized specific antibodies on the surface of potyvirus particles. For this purpose, potyviruses, flexuous filamentous phytoviruses with a high aspect ratio, have been chosen. This technique allows analysis of the distribution of antibody labeling over the virus population. But, more importantly, it opens up the imaging of immune complexes decorating a single viral particle. Finally, its high resolution allows the characterization in situ of the ultrastructure of a single immune complex on the particle.