Gram's method

American  

[gramz] / græmz /

noun

(sometimes lowercase)

1. a method of staining and distinguishing bacteria, in which a fixed bacterial smear is stained with crystal violet, treated with Gram's solution, decolorized with alcohol, counterstained with safranine, and washed with water.

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Gram's method British  

noun

1. bacteriol a staining technique used to classify bacteria, based on their ability to retain or lose a violet colour, produced by crystal violet and iodine, after treatment with a decolorizing agent See also Gram-negative Gram-positive

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Etymology

Origin of Gram's method

Named after Hans C. J. Gram (1853–1938), Danish bacteriologist

Example Sentences

It stains with moderate rapidity with the ordinary anilin dyes, and is decolorized by Gram's method.

From Project Gutenberg

Young individuals are stained by Gram's method; older individuals are, however, Gram negative.

From Project Gutenberg

Stain: Gram's method coloured with aqueous fuchsine afterwards.

From Project Gutenberg

A. Gram's Method.—Young individuals give an intense reaction with this stain; old bacilli are easily decolourised, and degenerate forms are always Gram-negative, while single individuals have been observed which showed gradation from one pole of the cell to the other.

From Project Gutenberg

Gram's Method.—This method depends upon the fact that the protoplasm of some bacteria permits aniline gentian violet and Lugol's iodine solution, when applied consecutively, to enter into a chemical combination which results in the formation of a new blue-black pigment, only very sparingly soluble in absolute alcohol.

From Project Gutenberg