Which of the material is used as mordant in simple bacterial staining?
Which of the material is used as mordant in simple bacterial staining?
Iodine solution/Gram’s Iodine (mordant that fixes crystal violet to cell wall)
How can a basic dye stain bacteria?
A basic dye is a stain that is cationic (positively charged) and will therefore react with material that is negatively charged. The cytoplasm of all bacterial cells have a slight negative charge whengrowing in a medium of near neutral pH and will therefore attract and bind with basic dyes.
Why do we use basic dyes to stain most bacteria?
Basic Dyes carry a positive charge & are more used for staining than Acidic dyes. This is because opposite charges attract, basic dyes stain the negatively charged components of cells including nucleic acid & many proteins.
Which dye is used for identification of bacteria?
Gram Staining
| Table 1. Gram stain process | |
|---|---|
| Gram staining stems | Cell effects |
| Step 1: Crystal Violet primary stain added to the specimen smear | Stains cells purple or blue. |
| Step 2: Iodine mordant, makes the dye less soluble so it adheres to cell walls. | Cells remain purple or blue. |
What is basic stain?
A chemical used to add pigment to the nuclear or acidic components of cells.
Why are basic dyes used?
At the molecular level, basic dyes have amino groups, which are responsible for the molecule’s positive charge. Because of their cationic or positively charged properties, basic dyes are used in a variety of applications for products with anionic (negatively charged) properties.
Why are basic dyes used in simple stains?
Basic stains, such as methylene blue, Gram safranin, or Gram crystal violet are useful for staining most bacteria. Since the surface of most bacterial cells is negatively charged, these positively charged stains adhere readily to the cell surface.
What are basic dyes used for in microbiology?
Basic dyes used in biological staining ionize in solution to give cations (positively charged ions). The cation in a basic dye is the colored component of the dye molecule that binds to anionic groups of nucleic acids or acidic mucopolysaccharides.
What Colour are bacteria?
flushed with an alcohol solution, gram-positive bacteria retain the blue colour and gram-negative bacteria lose the blue colour. The slide is then stained with a weaker pink dye that causes the gram-negative bacteria to become pink, whereas the gram-positive bacteria remain blue.
What is the basic dye?
Basic dyes are water-soluble cationic dyes that are mainly applied to acrylic fibers, but find some use for wool and silk. Usually acetic acid is added to the dye bath to help the uptake of the dye onto the fiber. Basic dyes are also used in the coloration of paper.
What are basic dyes in microbiology?
The cation in a basic dye is the colored component of the dye molecule that binds to anionic groups of nucleic acids or acidic mucopolysaccharides. Basic dyes stain basophilic structures such as nuclei, ribosomes and GAGs. Examples of basic dyes are methylene blue, toluidine blue, thionine, and crystal violet.
What is the mordant and decolorizer used in microbiology?
Iodine is used a mordant and a 95% ethanol is used as a decolorizer. A 25% acetone or75% isopropanol can also be used. A gram safranin is used as a secondary dye. A gram positive bacteria yields to a purple color while a gram negative bacteria yields to a red color.
Why are ionic mordants used in staining?
There are various types of mordants, but the one typically used is ion because its electrical charge gets in contact with the electrical charge of a chemical dye. A large complex is created when the ion binds the dye, which is highly beneficial during the staining procedure.
What dye is used in Gram staining?
In a gram staining procedure, a crystal violet dye is used. Iodine is used a mordant and a 95% ethanol is used as a decolorizer. A 25% acetone or75% isopropanol can also be used. A gram safranin is used as a secondary dye. A gram positive bacteria yields to a purple color while a gram negative bacteria yields to a red color. (6, 7, 9)
What is the best mordent for natural dyeing?
Some of the common types of mordent for natural dyeing include the following: Alum – It is the commonly used mordant. It should be used with care because it can give a sticky feeling that does not come out. Copper – It brings out the greens in dyes. It is more like the same as using tin, but it is less harmful.
