Histopatho Staining Techniques PDF

Principle of staining basic stain is a chemical which can bind with the.cellular components and give them color Different dyes which can be used for staining are basic/cationic dyes (methylene blue, crystal violet, malachite green, safranin) and.anioninc/acidic dyes (eosin and picric acid) Cationic...

Principle of staining basic stain is a chemical which can bind with the.cellular components and give them color Different dyes which can be used for staining are basic/cationic dyes (methylene blue, crystal violet, malachite green, safranin) and.anioninc/acidic dyes (eosin and picric acid) Cationic dyes binds with the negatively charged cellular components such as those are present in cell membrane, whereas, anionic dye binds.with positively charged cellular components  Types of Staining Techniques :Gram’s staining This staining procedure is used to identify bacteria based on their cell wall.composition There are two types of Gram’s staining, and the bacteria can be divided into.gram positive or gram negative bacteria It uses crystal violet for the staining of cell walls, iodine as the mordant and  :Endospore staining This technique is used to find out the.presence of endospores in bacteria Endospores are tough, dormant structures.that are less permeable to dyes and stains Their presence makes the bacteria difficult to.kill The process involves heat fixing the specimen and dying it with a blend of.safranin and 5% diluted malachite green :Ziehl-Neelsen staining This technique is used to stain acid-fast bacteria such as Mycobacterium tuberculosis that do not stain with.Gram’s staining Carbol fuchsin is used as a stain, and methylene blue is.used as a counterstain :Haematoxylin and Eosin staining This staining procedure is used in histopathological.studies to observe thin tissue sections The hematoxylin stain colours the nuclei in blue and the.cytoplasm and its components in red or pink :Periodic Acid-Schiff (PAS) staining PAS staining is used to stain carbohydrate.molecules It is used on liver tissues, kidney, pancreas and ovaries to detect the presence of glycogen and.help in the diagnosis of diseases :Masson staining Masson’s trichrome is a three-colour staining procedure which is used for differentiating cells.from connective tissues It colours the muscle fibres and keratin to red,  Biological Stains Some of the most commonly used :biological stains are listed below :Acridine orange It is a fluorescent cationic dye that is selective to.nucleic acids It is used during the cell cycle to analyse DNA.molecules :Coomassie blue It is used in gel electrophoresis to stain the proteins.blue  :Crystal violet It is used in Gram’s staining along with iodine to stain.the bacterial cell wall in purple colour :Eosin It is used as a counterstain to hematoxylin that imparts.a red colour to the cytoplasm and its components :Ethidium bromide It provides a red-orange fluorescent stain to the DNA.after intercalating with the molecule :Iodine.It is used as a mordant in Gram’s staining  :Malachite green It gives a blue-green colour when used as a counterstain against safranin that is used in.endospore staining :Methylene blue It is used to stain animal cells because it.enhances the nuclei :Safranin It is a red cationic dye that is used as a counterstain in both Gram’s staining and.endospore staining  Mounting A sufficiently thin and suitably colored slice of biological material must be placed on glass slides for examination under the.microscope A drop of mounting media is applied to the sections, and the coverslip is carefully.dropped onto the sample using tweezers This process is called mounting in.histopathology :The purpose of Mounting The purpose of mounting is to protect the specimen from physical harm, to protect the section from bleaching or degradation due to oxidation, to preserve the slides for long-term storage, to allow simple handling and storage, and to.avoid section damage