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Molekula

Molekula

Methylene Blue trihydrate

SKU 35018936 CAS 7220-79-3 C16H18CIN3S·3H2O MW 373.90 In stock Bulk quantities on request

Supplying 4,500+ customers in over 80 countries

ISO 9001:2015 & ISO 14001:2015 certified · Supplying laboratories and industry since 2000 · Listed pack sizes are a starting point — we manufacture, source and repack to the quantity you need

Methylene Blue trihydrate is a synthetic phenothiazine dye and redox indicator widely used in biology, medicine, and industry for staining, dyeing textiles, and as a medical treatment for methemoglobinemia. It functions as a redox indicator in laboratories and as a photosensitizer in photodynamic therapy. This chemical has a CAS number of 7220-79-3, with the molecular formula C16H18ClN3S·3H2O and a molecular weight of 373.90 g/mol. It is stored at ambient conditions and carries a signal word of *Warning*. Molekula supplies Methylene Blue trihydrate from research to bulk quantities with full documentation and ISO 9001:2015 traceability.

Expect a response within hours Speak to a chemist: +44 (0) 3302 000333

Example image for illustration only. Other packaging and pack sizes are available.

Pricing & pack sizes

Pack sizes & pricing

These pack sizes aren't a limit. Molekula manufactures, sources and repacks to order — if you need 500 kg and only see 1 kg listed, . We quote from grams to multi-tonne.

Need a different size? Add the nearest pack and change the size in your basket — we price it at the same rate per unit.

  • 100 g — $111.80 per pack
  • 1 kg — $889.20 per pack

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Specifications

Property Value
Appearance Dark green crystalline powder
Identification To conform to standard
Loss on Drying ≤22%
Solubility Clear blue solution
Assay ≥82%
Residue on Ignition ≤1.2%
Copper (Cu) ≤200ppm
Assay (dried basis) 98 - 103%

Storage & handling

Property Value
Storage Temperature Ambient
Acidity Acid

Literature values

Published physical properties of the substance, not batch specifications.

Property Value
Melting Point 190 °C (decomposes)

Source: PubChem CID 104827 (CAMEO Chemicals)

Identification

Property Value
SKU 35018936
CAS Number 7220-79-3
IUPAC Name [7-(dimethylamino)phenothiazin-3-ylidene]-dimethylazanium;chloride;trihydrate
Molecular Formula C16H18CIN3S·3H2O
Molecular Weight 373.90
Exact Mass 373.1227
SMILES CN(C)C1=CC2=C(C=C1)N=C3C=CC(=[N+](C)C)C=C3S2.O.O.O.[Cl-]
InChIKey XQAXGZLFSSPBMK-UHFFFAOYSA-M
InChI InChI=1S/C16H18N3S.ClH.3H2O/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;3*1H2/q+1;;;;/p-1
PubChem CID 104827
REACH Code Y113
Tariff Code 32129000

Safety & GHS

Warning
  • GHS pictogram — Health Hazard Health Hazard GHS07
  • GHS pictogram — Serious Health Hazard Serious Health Hazard GHS08

Hazard statements

  • H302 Harmful if swallowed
  • H315 Causes skin irritation
  • H319 Causes serious eye irritation
  • H335 May cause respiratory irritation
  • H373 May cause damage to organs through prolonged or repeated exposure

Precautionary statements

  • P261 Avoid breathing dust/fume/gas/mist/vapours/spray
  • P280 Wear protective gloves/protective clothing/eye protection/face protection
  • P301+310 IF SWALLOWED: Immediately call a POISON CENTER or doctor/physician
  • P303+361 IF ON SKIN (or hair): Remove immediately all contaminated clothing. Rinse with water/shower
  • P305+351+338 IF IN EYES: Rinse with water for several minutes. Remove contact lenses if present and easy to do. Continue rinsing
  • P308+313 IF exposed or concerned: Get medical advice/attention

Documents

Safety Data Sheets (SDS)

Available in English, French, German, Italian, Spanish.

Certificate of Analysis (CoA) by batch

Enter a lot or batch number to retrieve the CoA for that specific batch. We can generate one from spec data if no PDF is on file.

Synonyms

  • 3,7-Bis(dimethylamino)phenothiazin-5-ium chloride trihydrate
  • 3,7Bis(dimethylamino)phenazathionium chloride trihydrate
  • 7-(DIMETHYLAMINO)-3-(METHYLIMINO)-3H-PHENOTHIAZINE, 3-METHOCHLORIDE TRIHYDRATE
  • C.I. Basic Blue 9, trihydrate
  • C16H18ClN3S
  • METHYLTHIONINE CHLORIDE TRIHYDRATE
  • METHYLTHIONINE TRIHYDRATE
  • methylthioninium chloride trihydrate
  • Phenothiazin-5-ium, 3,7-bis(dimethylamino)-, chloride, trihydrate
  • TETRAMETHYLENE BLUE TRIHYDRATE

Frequently asked questions

What is Methylene Blue trihydrate commonly used for?

Methylene Blue trihydrate is primarily used as a dye in biological staining, a redox indicator in laboratories, and medically for methemoglobinemia treatment and as an antiseptic.

What is the chemical formula and molecular weight of Methylene Blue trihydrate?

The chemical formula is **C₁₆H₁₈ClN₃S·3H₂O**, and the molecular weight is **373.90 g/mol**.

How should Methylene Blue trihydrate be stored?

Store at **ambient temperature** in a tightly sealed container, away from light and moisture.

What grades or purities of Methylene Blue trihydrate does Molekula supply?

Molekula supplies **analytical and reagent-grade Methylene Blue trihydrate**, meeting standard purity requirements for laboratory and research applications.

Can Molekula supply Methylene Blue trihydrate in bulk quantities?

Yes, Molekula can provide Methylene Blue trihydrate in bulk, with quantities tailored to your specific requirements—please contact us for details.

What documentation comes with an order of Methylene Blue trihydrate?

Each order includes a **Certificate of Analysis (CoA)**, Material Safety Data Sheet (MSDS), and a product specification sheet.

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