Which Nanogold labeling reagent should I use to label antibodies – IgG, Fab or Fab?
Generally, we recommend Monomaleimido Nanogold for antibody labeling. Because labeling with this reagent is directed to the hinge region in IgG molecules or Fab’ fragments, it does not hinder the antigen combining region from binding to its target. However, excellent labeling may also be obtained by using Mono-Sulfo-NHS-Nanogold, and in tests we have found that antibodies labeled in this manner can produce labeling equivalent to or even better than those labeled with Monomaleimido Nanogold.