1.04122

Methylene blue (C.I.52015)

• Synonym(s): Methylene Blue trihydrate
• Empirical Formula (Hill Notation): C₁₆H₁₈ClN₃S · 3H₂O
• CAS Number: 7220-79-3
• Molecular Weight: 373.90
• Beilstein/REAXYS Number: 3599847
• MDL number: MFCD00012111
• UNSPSC Code: 41116130

Properties

• form: solid
• Quality Level: 200
• potency: 1180 mg/kg LD₅₀, oral (Rat)
• composition: Dye, ≥82% spectrophotometric assay
• pH: 3 (20 °C, 10 g/L in H₂O)
• mp: 190 °C (dec.) (lit.)
• solubility: 50 g/L
• density: 1.757 g/cm³ at 22 °C
• bulk density: 400‑600 kg/m³
• application(s): diagnostic assay manufacturing; hematology; histology
• storage temp.: 2-30°C
• SMILES string: [Cl-].CN(C)c1ccc2N=C3C=C\C(C=C3Sc2c1)=[N+](/C)C
• InChI: 1S/C16H18N3S.ClH/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/q+1;/p-1
• InChI key: CXKWCBBOMKCUKX-UHFFFAOYSA-M

Description

General description

Methylene blue (C.I. 52015) for microscopy Certistain^® is a dry dye that is used in bacteriology for an overview stain and as counterstaining for Ziehl-Neelsen method in sample material of human origin. Bacteria appear blue. The dye has a further important application in hematology: Methylene blue and eosin are the main components of many staining solutions and dye mixtures. As a CERTISTAIN^® dye it is chemically quality-certified according to highest standards and strict specifications.

Application

for microscopy Certistain^®

Analysis Note

Dye content (spectrophotometrically): ≥ 82 %
Identity
- Chloride:
passes test
- UV/VIS-Spectrum: passes test
Absorption maximum λ max (ethanol 50 %): 660 - 665 nm
Spec. Absorptivity A 1%/1cm (λ_max; 0.003 g/l; ethanol 50 %): 2250 - 2750
TLC-Test: passes test
Loss on drying (110 °C): 10 - 15 %
Suitability for microscopy: passes test

Legal Information

CERTISTAIN is a registered trademark of Merck KGaA, Darmstadt, Germany

Safety Information

• pictograms: GHS07
• signalword: Warning
• hcodes: H302
• pcodes: P264 - P270 - P301 + P312 - P501
• Hazard Classifications: Acute Tox. 4 Oral
• Storage Class: 11 - Combustible Solids
• wgk_germany: WGK 2