Immuno-electron Microscopy Techniques: I. Pre-embedding Immunolabelling of Intracellular Antigens Using 1 nm Colloidal Gold Probes and Silver Enhancement
Abstract
As an alternative procedure to post-embedding immunolabelling in resin-embedded samples, pre-embedding immunolabelling increased the likelihood of antigen recognition by the antibody during immunohistochemical localization. The development of one-nanometer colloidal gold conjugated antibodies offers new probes for intracellular pre-embedding immunolabelling. In couple with silver, enhancement was examined in three commonly used sample preparations extracted cell suspension, detergent permeabilized cell cultures, and vibratome tissue sections. One nanometer gold probes have greater sensitivity over larger gold probes as demonstrated in the extracted cell preparations. However, intact cells need to be rigorously permeabilized to allow the one-nanometer gold probes to reach antigen sites. One nanometer gold probes can penetrate 4-5 micrometers into vibratome sections treated with detergent permeabilization.