What would happen if I omitted adding Gram's Iodine in the Gram Stain procedure?
The violet color will wash away with water. The reason for adding the iodine is that it chemically binds to the crystal violet, and makes a water-insoluble complex.
If you omit adding Gram's Iodine in the Gram Stain procedure, the staining results will not be accurate or reliable. Gram's Iodine is a critical step in the Gram Stain procedure as it serves as a mordant. A mordant is a substance that helps to fix the primary stain (Crystal Violet) onto the peptidoglycan layer of bacterial cells.
When Gram's Iodine is added to the stained slide, it forms a complex with the primary stain, creating a larger molecule that gets trapped within the peptidoglycan layer. This complex provides structural support to the cell wall during the decolorization step.
By skipping the addition of Gram's Iodine, the primary stain will not be effectively trapped within the peptidoglycan layer. Thus, during the subsequent decolorization step, both Gram-positive and Gram-negative bacterial cells will lose their initial stain. This will lead to unreliable staining results, making it difficult to distinguish between Gram-positive (purple) and Gram-negative (pink) bacteria.
To ensure accurate results, it is crucial to follow the Gram Stain procedure precisely and include the step of adding Gram's Iodine as a mordant.