As per the exact chemistry, I am unsure, but basically the iodine acts to "set in" the stain by reacting the dye (crystal violet) from the previous step with the peptidoglycan layer, forming a layer which is now insoluble in the following step where the layer is washed with EtOH. If the cell is Gram (-), the iodine doesn't do much and the dye is washed away.
Lugol's Iodine = 20g Potassium Iodide + 10g Iodine dissolved in 1L H2O Gram's Iodine = 6.7g potassium iodide + 3.3g Iodine dissolved in 1L H2O Recipe's taken from Flinn Scientific Catalog I have on campus. Looks to me as Gram's is just a dilute version of Lugol's. Same ratio of KI:I just less of it. Couldn't tell you much about differences in application however.
Iodine crystals are solid, crystalline form of elemental iodine, while iodine solution is a liquid mixture of elemental iodine and either alcohol or water. Iodine crystals are typically used for storage and long-term preservation, while iodine solution is commonly used for disinfection and medical purposes.
Povidone-iodine is a stable chemical complex of polyvinylpyrrolidone and iodine, used as an antiseptic. Tincture iodine is a solution of iodine in alcohol, commonly used to disinfect skin before surgeries. Tincture iodine is more potent but can irritate the skin, while povidone-iodine is less irritating and commonly used in clinical settings.
An Iodine Flask is essential an Erlenmeyer Flask with a stopper used for the wet chemical analysis "Iodine Determination" . This analysis is typically performed on fatty acids, oils and shellac varnishes.
this is because iodine is not soluble in water and it is soluble in potassiuim iodide. so KI is used as a solvent, and the resulting potassium iodate is soluble in watre so we can determine iodine in the ticture.
Gram's iodine is called a mordant because it fixes the primary stain to the cell wall and adds any color.
Iodine is used in Gram staining as a mordant, which helps to bind the crystal violet dye to the cell wall of bacteria. This mordant-iodine complex forms larger complexes with the crystal violet dye, making it difficult for the dye to be washed away during the decolorization step. This allows for differentiation of Gram-positive and Gram-negative bacteria based on their ability to retain the crystal violet dye.
Gram's iodine stain is applied after the culture is stained with the primary stain. It acts as a mordant, fixing the primary stain to the cell wall while lending no additional colour to the cell (i.e. the mordant itself is not a stain). The mordant is only able to fix the stain to Gram-positive bacteria because of the characteristic thick, peptidoglycan coat that they possess. Because the mordant is not able to fix the stain to Gram-negative bacteria (who's coat have a different composition), the crystal violet stain will wash away from Gram-negative bacteria when the decolourizing agent is added.
Tincture iodine in trichrome stain is used as a mordant to enhance the staining of collagen fibers. It helps to improve the contrast and visibility of collagen in the tissue sample.
Mordant reagents are used in staining techniques to help bind dyes to specific structures. Different mordants are needed for different types of dyes and tissue components. For example, in Gram staining, the mordant reagent is iodine, which helps bind the crystal violet dye to the bacterial cell wall.
Yes, sodium chloride can be used as a mordant.
a mordant is used for the dyeing to try it
Gram's iodine is called a mordant because it fixes the primary stain to the cell wall and adds any color.
No, iodine is not a basic stain. Iodine is commonly used in Gram staining to identify bacteria as either Gram-positive or Gram-negative based on their cell wall composition. It acts as a mordant in the staining process and helps to fix the crystal violet stain in Gram staining.
Heat is the mordant used in the spore stain, it fixes the primary stain.
The mordant used in the process of gram staining is called crystal violet.
Alum was used as a mordant in dyeing. Salt is used as a mordant in dyeing and calico-printing. Mordant is very sarcastic and painful wit or speech. It is also known as a substance that attaches dyes to materials.