methylene blue

American  

noun

Chemistry, Pharmacology.

1. a dark-green, crystalline compound, C 1 6 H 1 8 ClN 3 S, that dissolves in water to form a deep-blue solution: used chiefly as a dye, as a bacteriological and biological stain, and as an antidote for cyanide poisoning.

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methylene blue British  

noun

1. Also called: methylthionine chloride.  a dark-green crystalline compound forming a blue aqueous solution, used as a mild antiseptic and biological stain. Formula: C 16 H 18 N 3 SCl.3H 2 O

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methylene blue Scientific  

1. A basic dye that forms a deep blue solution when dissolved in water. It is used as an antidote for cyanide poisoning and as a bacteriological stain. Chemical formula: C ₁₆ H ₁₈ N ₃ SCl.

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Etymology

Origin of methylene blue

First recorded in 1885–90

Example Sentences

See Examples For:

methylene blue

To gauge the fat content of the cream brought by farmers, the dairy would insert methylene blue in a sample and waited for its lactic acid to dissolve the color.

From New York Times ● Jan. 9, 2023

The oxidized form of methylene blue is reduced by NADH, and its reduced form is oxidized by O2.

From Textbooks ● Jun. 9, 2022

Explain the use of methylene blue as an antidote for rotenone poisoning.

From Textbooks ● Jun. 9, 2022

An independent team of researchers found that, in animal models at least, methylene blue clears amyloid-β but has no effect on tau whatsoever.

From Nature ● Jul. 13, 2011

This method, however, cannot pass as entirely free from error, as Ehrlich frequently found that when the experiment lasts some time the methylene blue often forms granular precipitates that may be confused with the granules.

From Histology of the Blood Normal and Pathological by Myers, W.