How does safranin affect Gram-positive cells? Safranin penetrates the cell wall, but not enough of it is retained to cause a color change...... In the Gram-positive cell walls, most of the spaces between the molecules that make up peptidoglycan are already occupied by crystal violet/iodine complexes.
What is the use of Safranine Solution in Gram Staining?
Following steps are followed for gram staining in which there is use of Safranine Solution also.
1. Prepare a thin smear on clear, dry glass slide.
2. Allow it to air dry and fix by gentle heat.
3. Flood with Gram's Crystal Violet (S012) for 1 minute. (If over staining results in improper decolourization of known gram-negative organisms, use less crystal violet).
4. Wash with tap water.
5. Flood the smear with Gram’s Iodine (S013). Allow it to remain for 1 minute.
6. Decolourize with Gram's Decolourizer (S032) until the blue dye no longer flows from the smear. (Acetone may be used as a decolourizing agent with caution, since this solvent very rapidly decolourized the smear).
7. Wash with tap water.
8. Counter stain with 0.5% w/v Safranin (S027) for 20 seconds and rinses off with water.
9. Wash with tap water.
10. Allow the slide to air dry or blot dry between sheets of clean bibulous paper and examine under oil immersion objective