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M9140

Sigma-Aldrich

Methylene blue

Dye content, ≥82%, certified by the Biological Stain Commission, powder

Synonym(s):

Basic Blue 9, 3,7-bis(Dimethylamino)phenazathionium chloride, Tetramethylthionine chloride

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About This Item

Empirical Formula (Hill Notation):
C16H18ClN3S · xH2O
CAS Number:
Molecular Weight:
319.85 (anhydrous basis)
Colour Index Number:
52015
Beilstein:
3599847
EC Number:
MDL number:
UNSPSC Code:
12171500
PubChem Substance ID:
NACRES:
NA.47
Pricing and availability is not currently available.

Product Name

Methylene blue, certified by the Biological Stain Commission

grade

certified by the Biological Stain Commission

Quality Level

form

powder

composition

Dye content, ≥82%

technique(s)

microbe id | staining: suitable

color

dark green

solubility

H2O: 4mg/4ml

application(s)

diagnostic assay manufacturing
hematology
histology

storage temp.

room temp

SMILES string

CN(C)C1=CC=C2C(SC(C3=N2)=CC(C=C3)=[N+](C)C)=C1.[H]O[H].[Cl-]

InChI

1S/C16H18N3S.ClH.H2O/c1-18(2)11-5-7-13-15(9-11)20-16-10-12(19(3)4)6-8-14(16)17-13;;/h5-10H,1-4H3;1H;1H2/q+1;;/p-1

InChI key

WQVSELLRAGBDLX-UHFFFAOYSA-M

Gene Information

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General description

Methylene blue is a compound that occurs as crystals or crystalline powder, having a bronze-like luster. It is soluble in water, chloroform and partially soluble in alcohol.[1] It is a photoactive dye, which is a member of phenothiazine family.[2]

Application

Methylene blue has been used:
  • to stain vaginal cells[3]
  • for the preparation of protein aqueous ink[4]
  • to evaluate cell survival by staining[5]

Biochem/physiol Actions

Methylene blue is used as a bacteriologic stain or dye and indicator.[6] It mediates the inactivation of enveloped viruses in plasma, when exposed to visible light.[2] It is an inhibitor of nitric oxide synthase and guanylate cyclase.[7] It also plays a key role in medicine as an antimalarial agent, reducing agent in methemoglobinemia and inducer of apoptosis in cancer cells.[7]

Suitability

Certified for use in Mallory′s phloxine-methylene blue stain; Levine & Black stain for bacteria in milk; Wright stain for blood smears.

Pictograms

Exclamation mark

Signal Word

Warning

Hazard Statements

Precautionary Statements

Hazard Classifications

Acute Tox. 4 Oral

Storage Class Code

11 - Combustible Solids

WGK

WGK 3

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

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DJ-1 deficiency triggers microglia sensitivity to dopamine toward a pro-inflammatory phenotype that is attenuated by rasagiline
Trudler D, et al.
Journal of Neurochemistry, 129(3) (2014)
Methylene blue: revisited
Ginimuge PR and Jyothi SD
Journal of Anaesthesiology, Clinical Pharmacology, 26(4), 517-517 (2010)
RNA determinants of translational operator recognition by the DNA polymerases of bacteriophages T4 and RB69.
Petrov VM and Karam JD
Nucleic Acids Research, 30, 3341-3341 (2002)
Transfusion Medicine and Hemostasis: Clinical and Laboratory Aspects (2008)
Protein-based soft micro-optics fabricated by femtosecond laser direct writing
Sun YL, et al.
Light: Science & Applications, 3(1), e129-e129 (2014)

Articles

Serotonin is stored in cells and metabolized by MAO, influencing CNS, GI, and platelet functions.

Questions

1–9 of 9 Questions  
  1. Is this ingredient suitable for use as a redox indicator? What is the main difference compered to that used as an indicator?

    1 answer
    1. Yes, in addition to biological stain applications, Methylene Blue is also commonly used as a redox indicator. Oxidized solutions will appear blue in color and will turn colorless when mixed with a reducing agent. A reduced or clear solution will turn blue when exposed to an oxidizing agent. Methylene blue is considered a basic dye, but not commonly used as an pH indicator. Methyl Blue, which is a chemically different compound, is more commonly used as a pH indicator. Please see the link below to review this compound:
      https://www.sigmaaldrich.com/product/sial/95290

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  2. Which is the granulometry of this powder?

    1 answer
    1. The quality control testing only requires that the methylene blue powder appear as a powder. There is no requirement to define the powder as either coarse, medium or fine powder.

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  3. Is there any information available on ammonium molybdate's role in fixing methylene blue dye?

    1 answer
    1. There is no information available regarding the use of ammonium molybdate for mixing methylene blue staining.

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  4. Is there any testing conducted for lead and other heavy metals in any of the available methylene blue products?

    1 answer
    1. Medicinal grade and food grade dyes are likely to undergo testing for lead and other heavy metals. It is unlikely that Methylene Blue is offered as a food grade dye. M9140 is not subjected to testing for lead and other heavy metals because it is not intended for human or veterinary use.

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  5. Are various powdered methylene blues suitable for marking brain regions in live mice? There are issues visualizing it after staining, suspected due to outdated methylene blue. Assistance is required in choosing the right type for preparation for identifying specific brain regions.

    1 answer
    1. There is no mention of which methylene blue has been problematic. Biological dyes usually lack expiration dates. The recommended catalog number is M9140, which is certified by the Biological Stain Commission (BSC) for staining nuclei blue using paraffin sections and for staining bacteria in milk. Other applications of Methylene Blue include staining white blood cells in Wright Stain, oversight staining, supra vital staining, and staining nerves, nerve fibers, neuronal processes, live non-neuronal cells, tumors, and as a surgical marker.Fresh and aged dyes can yield different reactions. Effective solutions may need fresh preparation. Some dyes have set expiration dates due to deterioration. While using two blue dyes is unusual; thionin is commonly used for Nissl staining.

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  6. How can Methylene blue, Product M9140, be used?

    1 answer
    1. Probably its most important application is as an in vitro diagnostic bacteriology, cytology, hematology, and histology stain. Methylene Blue serves as a precursor to the Methylene Azures and as a component of the various Ramanowsky-type blood stains (Wright, Leishman, Giemsa and others). While pure Methylene Blue is not a good nuclear stain, it readily undergoes oxidative demethylation to form the various Methylene Azures, which are good nuclear stains.

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  7. What is the Department of Transportation shipping information for this product?

    1 answer
    1. Transportation information can be found in Section 14 of the product's (M)SDS.To access the shipping information for this material, use the link on the product detail page for the product.

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  8. What is the solubility of Methylene blue, Product M9140?

    1 answer
    1. The product is soluble in water at 50 mg/mL, EGME at 60 mg/mL and ethanol at 70 mg/mL. EGME is an abbreviation for ethylene glycol monomethyl ether, also known as 2-methoxyethanol or methyl cellosolve.

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  9. How is dye content determined for Methylene blue, Product M9140?

    1 answer
    1. Dye content is determined spectrophotometrically by noting the dye's absorbance peak, which is typically near 665 nm, or by calculating the ratio of the absorbances at 650 nm over 680 nm. (The dye exhibits smaller peaks at approximately 292 and 246 nm).

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