Safranin O (C.I. 50240) is a CERTISTAIN dry dye that is used for the preparation of a staining solution for e.g. Gram stain procedures in smears and sections of human origin in bacteriology. The Gram staining allows a fast differentiation of bacteria in Gram-positive and Gram-negative.
It is mostly utilized for the identification of cartilage, mucin, and mast cell granules. The safranin stain works by binding to acidic proteoglycans in cartilage tissues with a high affinity forming a reddish-orange complex. The binding made cartilage tissues appear red when observed under the microscope.
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.
BioGnost's Gram Safranin solution is used for contrast staining of bacterial species that did not retain their primary dye, i. e. Gram-negative bacteria. That enables differentiating the blue and purple-colored Gram-positive bacteria from the red-colored Gram-negative bacteria.