Histology Articles
Here are a few guidelines which you can use to process fixed tissue using Histo-Clear and Histo-Clear II: Histo-Clear Automated Tissue Processing Schedule Process Bath 18 Hour Cycle (Time in Hours) 24 Hour Cycle (Time…
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.…
Most dyes used to visualize the membranes and organelles of the cell are water soluble. The embedded wax must therefore be removed prior to staining. This is done by effectively reversing the tissue processing schedule.…
To preserve and support a stained section for light microscopy, it is mounted on a clear glass slide, and covered with a thin glass coverslip. The slide and coverslip must be free of optical distortions,…
- Working Safely with Fixatives
- The Chemistry of Dyes and Staining
- Suggested procedures for processing fixed tissue
- Staining Procedures
- Sectioning
- Overview of the Paraffin Technique
- Overview of Fixation
- Non-Aldehyde Fixatives
- Mounting Tissue Sections
- Factors Affecting Fixation
- Embedding
- Dehydration
- Decalcifying Tissue for Histological Processing
- Clearing Tissue Sections
- Artifacts in Histologic Sections
- Aldehyde Fixatives