A thin sample is initially incubated with a primary antibody. A secondary antibody is then added which is labelled with a gold nanoparticle. Gold nanoparticle labels are useful as they are very easy to spot as it is electron dense and is seen as a black dot on an electron microscope
Using an array of antibodies in a yeast cell for example the protein in the spindle pole body can be localised.
However, this method can give a misleading 2D image so further methods such as; tomography, z-stacks and single particle analysis can be used to create a more precise 3D image .
- ↑ Molecular Biology of the Cell, Alberts et.al, 2008