What is histochemical staining?
A staining method used to detect polysaccharides such as glycogen, and mucosubstances such as glycoproteins, glycolipids, and mucins in tissues and fungal hyphae.
How do you Destain slides?
Wash slides in deionized or distilled water for 5 min at room temperature. Destain slides in 0.5% HCl in 70% ethanol for 5-15 min at room temperature. Wash slides in deionized or distilled water for 5 min at room temperature.
Can you Restain a slide?
This is possible. It is important to mount the sections on adhesive slides. Do a conventional HE-stain. Afterwards you can loose the coverslip again by immerse the slide in xylen till the coverslip can easily be lifted.
What is histochemical method?
Histochemistry is an important technique that is used for the visualization of biological structures. As such, it is concerned with the identification and distribution of various chemical components of tissues through the use of stains, indicators as well as microscopy.
What is a histochemical?
: a science that combines the techniques of biochemistry and histology in the study of the chemical constitution of cells and tissues.
How do you Restain an improperly stained section?
With the regressive method, overstaining the tissue section with a neutral hematoxylin solution is the initial step. An acid alcohol is then used to remove excess stain, followed by an alkaline solution to achieve a neutralized tissue section. Stain intensity is controlled by visual examination with a microscope.
How can we remove the stain from an Overstained slide?
1% Acid Alcohol should do the trick just fine. HCL in 70% ethanol. Rinse either with 0.25% hydrochloric acid (HCl) for 2-5 seconds or 1% acid alcohol (1ml Conc HCl in 100ml ethanol) to remove excess stain from the slide, Then keep the slides in running water for 3 minutes for blueing.
Can you leave slides in xylene?
*You can leave slides in xylene overnight to get good clearing of any water. Coverslip slides using Permount (xylene based).
What is the principle of special staining?
In principle, they work by taking advantage of intra- and extra-cellular chemical reactions between the tissue components and dyes. Typically they use a chemical or dye with an affinity for whatever is under investigation, enabling specific tissues, structures, or even microorganisms to be stained.
What is histochemical reaction?
Histochemistry refers to procedures in which tissue sections act as the medium in which biochemical reactions are carried out by the addition of substrates, inhibitors, or other chemicals.
Why do medical scientists apply histochemical stains to samples of tissues and cells?
Staining is used to highlight important features of the tissue as well as to enhance the tissue contrast. Hematoxylin is a basic dye that is commonly used in this process and stains the nuclei giving it a bluish color while eosin (another stain dye used in histology) stains the cell’s nucleus giving it a pinkish stain.
What is histochemical methods?
What is the principle of staining?
In positive staining, the surface of the bacterial cell takes on the colour of the stain. When basic stain is applied, there is an attraction between the negatively charged cell surface and positively charged chromophore, which leads to staining of the cell (Figure 3.2).
What is Leishman stain procedure?
Leishman Stain is a neutral stain for blood smears which was devised by the British surgeon W. B. Leishman (1865–1926). It consists of a mixture of eosin (an acidic stain), and Methylene blue (a basic stain) in Methyl alcohol and is usually diluted and buffered during the staining procedure.
What is H and E staining used for?
H and E staining helps identify different types of cells and tissues and provides important information about the pattern, shape, and structure of cells in a tissue sample. It is used to help diagnose diseases, such as cancer.
How do you stain a slide at home?
To begin, use a 1:1 dilution ratio of dye solution to water. Mount your specimen on a glass slide. For a simple wet mount, apply a drop of water to the slide and carefully place the specimen on the wet portion. Apply a few drops of diluted dye to the sample.
How long can slides stay in xylene?
If you have slides with with histological section 3-5 microns, it should be sufficient to dewate them in three xylene baths for 5 minutes. This time should be enough.
Why is xylene used after staining?
Xylene is such an intermedium. Xylene is also required to eliminate the paraffin from thin paraffin sections prior to staining with aqueous staining solutions and thus to prepare the sections for the descending alcohol series.
Which are the two theories of staining?
Theories of staining : Physical theories : 1. Simple solubility e.g. Fat stains are effective because the stain is more soluble in fat than in 70% alcohol. 2. Absorption: This is a property by which a large body attracts to itself minute particles from a surrounding medium.
What is the optimal temperature for a histochemical reaction?
Most fixed tissues will section best within the range of −7 to −12°C, depending on the hardness of the tissue. Small blocks of undecalcified cancellous bone can be sectioned but care must be taken to remove any cortical bone fragments prior to freezing.
What are the Special stains in histopathology?
Special stains in histopathology. 2. H&E stain is routine stain. – It is the preliminary or the first stain applied to the tissue sections – Gives diagnostic information in most cases. A special stain is a staining technique to highlight various individual tissue component once we have preliminary information from the H&E stain.
What are some examples of histochemical methods?
Examples of Histochemical Methods: 1. Ions Iron (ferric ions – Fe3+) • Perls’s reaction: – sections of tissues are incubated in a mixture of potassium ferrocyanide and hydrochloric acid – result: insoluble dark blue precipitate of ferric ferrocyanide • Diagnostic application: – patients with diseases that store iron (eg. hemochromatosis) 10.
What are the basic dyes used to stain RNA?
18. 4.Nucleic Acids – RNA • RNA-rich organelles are stained with basic dyes • i.e.: toluidine blue, methylene blue In this procedure, one of 2 adjacent sections is treated with ribonuclease (RNase) to remove RNA; then both are stained with basic dyes (eg, hematoxylin, toluidine blue, methylene blue). 19.
What are some examples of enzyme histochemistry?
Examples: Million reaction for tyrosine, Sakaguchi reaction for arginine, tetrazotized benzidine reaction for tryptophan. Specific classes of enzymes can be detected by the techniques of enzyme histochemistry. Specific proteins can now be localized by using immuno- histochemistry. 17. Fuelgen reaction- acinar cells staining