Gram's crystal violet 500ml - Merck
The Gram staining allows a fast differentiation of bacteria in Gram-positive and Gram-negative.
Themureine structure of the bacteria walls is the basis of the color affinity.
Bacteria will be stained with Gram'scrystal violet solution - an aniline dye - in the first step.
After the treatment with iod solution (Lugolʼs solution), a dye-iod complex will form.
During the decolorizing step, this complex stays in the multilayer mureine structures of the Gram-positive bacteria and they will appear blue.
Gram-negative bacteria have monolayer mureine structure only, the dye-iod complex does not stay bound to the cellwall, they will be decolorised .
Gram-negative bacteria will be counterstained by Gram's safranin solution and appear
orange.
A bottle with 500 ml Gram's safranin solution is sufficient for staining up to 250 slides.
it is also available as part of the Gram-color stain set.
It is an IVD product and CE registered