Although secondary fixation in osmium tetroxide provides some areas of electron density, this is usually not sufficient to provide high contrast, high definition images. A number of staining techniques are available to enhance the contrast…

The ultrathin sections required in TEM are cut with knives of glass, diamond or sapphire. These materials produce extremely hard, ultrasharp edges, but they are brittle and subject to damage. Glass knives are produced as…

Sections for TEM must be less than 80 nm thick in order to allow at least 50% of the electron beam to penetrate the sample. This can only be accomplished by using resins for embedding…

The most popular fixatives for TEM work are aldehydes and osmium tetroxide. Aldehyde based fixatives react with amines and other nucleophiles in the tissue, most notably lysine and arginine, generating cross-linked proteins. The cross linking…

The resolution of a microscope is limited by the wavelength of light passing through the sample. For visible microscopes using 400 nm light (blue light), the limit of resolution is one half the wavelength, or…

Light microscopy makes use of primarily two detection systems for immunohistochemistry – fluorescence and enzyme labeling, while electron microscopy relies on the deposition of electron dense materials at the site of antibody binding. Techniques for…

The antibody systems used in Immunohistochemistry can be broadly divided into two types, direct and indirect. With the direct method the visualizing agent is attached directly to the antibody that will bind with the antigen.…

Immunohistochemistry is the application of antibody/antigen interactions to provide information about biological systems. The body’s response to the introduction of a foreign agent, known as the immune response, results in the production of antibodies which…