What colors do gram-positive and gram-negative bacteria stain?
I know this is more of a Biology question, but this is the closest thing I could find. Do you know what colors gram-positive and gram-negative stain?
First, the cells are stained purple with crystal violet. The slide is then treated with iodine/iodide
solution, and then decolorized with a solvent (acetone, or alcohol) that dissolves the
iodine/crystal violet complex. Gram-positive cells remain purple, and Gram-negative cells are
decolorized.
To see the Gram-negative cells, a red counterstain is used (safranin or acid fuchsin). After
counterstaining, the Gram-positive cells are purple and the Gram-negative cells are red.