See Also: Gram's stain(medicine)
Gram stain(medicine)
gram stain(encyclopedia)
half-a-gram stain(medicine)
Weigert-Gram stain(medicine)
Stirling's modification of Gram's stain(medicine)
Herbal medicine (botanical medicine, herbology, phytomedicine)(health)
Medicine Lodge Memorial Hospital- Medicine Lodge(health)
gram(4)(dictionary)
gram(encyclopedia)

Gram stain (medicine)


Gram stain
<microbiology, procedure> A method of staining bacteria using a violet stain. The gram staining characteristics (denoted as positive or negative) can assist in the identification of the offending bacteria.

A heat fixed bacterial smear is stained with crystal violet (methyl violet), treated with 3% iodine/potassium iodide solution, washed with alcohol and counterstained. The method differentiates bacteria into two main classes, gram-positive and gram-negative. Certain bacteria, notably mycobacteria, that have walls with high lipid content show acid-fast staining the stain resists decolouration in strong acid.