Periodic Acid-Schiff (PAS) staining is a histochemical method used to demonstrate carbohydrate and carbohydrate-rich compounds in tissue sections. It is the process where periodic acid is used to oxidize the 1,2-glycol groups of polysaccharides, mucin, glycogen and fungal cell wall components into aldehyde groups. These aldehydes then react with Schiff’s reagent to produce a characteristic … Read more
Negative staining of viruses is the process in which the viral particles is visualized by embedding them in an electron-dense stain rather than staining the virus itself. It is the method where the background gets heavily stained while the virus remains unstained, so the particles appear as light structures against a dark surrounding. It is … Read more
Wheatley Trichrome Staining is the permanent staining method used in parasitology for detecting intestinal protozoans from stool samples, and it is mainly applied when cysts and trophozoites is to be identified in a fixed smear. It is the process in which three dyes are used so that the parasite structures get a clear differential colour … Read more
Amoeba staining is the process used in laboratories for observing the structural details of free-living and intestinal amoebae. It is needed because most amoebae are transparent in fresh samples, and their internal parts cannot be seen clearly without color contrast. It is the process that helps in identifying pathogenic forms like Entamoeba histolytica from non-pathogenic … Read more
A light microscope may be used to see and examine the vacuole’s structure. While the vacuole doesn’t stain as the other organelles of the cell (because it does not contain many constituents that stain) tests have demonstrated that staining is possible for this organelle because the vacuole’s sap absorbs and stores dyes that are colored.
Masson’s Trichrome Staining (MTS) is a special histological staining method used to differentiate the connective tissue elements of a section. Principle of the Masson’s Trichrome Staining The principle of Masson’s Trichrome Staining is based on the differential penetration of dyes into tissue components of different density, and it is the process where electrostatic attraction and … Read more
What is positive staining of Virus? Positive staining of viruses is the process in which the viral particle is made dark on a light background. It is the opposite of negative staining where the virus image is light and the background becomes dark. It is used widely to study the diverse morphology of viruses especially … Read more
Auramine–Rhodamine staining is the process used to demonstrate acid-fast bacilli from clinical specimens and it is considered a modified form of the Acid-Fast staining technique. It is the process where fluorochrome dyes bind with the mycolic acid of the bacterial cell wall and it is visualized under a fluorescent microscope. It is the preferred screening … Read more
Silver staining is the process used for detecting and identifying proteins and nucleic acids in different gels, and it is highly sensitive in nature. It is the method where silver ions (Ag⁺) binds to different chemical groups present in proteins like carboxyl and sulfhydryl groups, and these ions is then reduced into metallic silver (Ag⁰). … Read more
Grocott-Gomori’s Methenamine Silver (GMS) stain is the histological staining method that is used mainly for the detection of fungal microorganisms in tissue sections and smears. It is the process that was first developed by Gomori and later modified by Grocott, and it is used because of its high sensitivity to demonstrate carbohydrates present in the … Read more
