The advantage of the osmium conductive metal coating for the detection of the colloidal gold-conjugated antibody by SEM

For the detection of the colloidal gold-conjugated antibody by scanning electron microscopy the comparison between the secondary and the backscattered electron images is necessary. After the various durations of osmium conductive metal coatings, enlargements of the diameters of the antibodies were observed. The thick coating reduced the contrast of the backscattered electron images. By the optimal thickness of the coating, the secondary electron image showed a minimum reduction in the resolution, and the backscattered electron image showed not only the gold particles with high contrast, but also the outline of the basic morphology.