Methylene blue (catalogue No. M9140) is a phenothiazine-based dye, certified by the Biological Stain Commission (BSC), supplied as a powder with ≥ 82 % dye content. It is used for staining bacteria, histological specimens, hematology slides and other laboratory staining procedures. The dye dissolves in water and is compatible with standard staining protocols in clinical, microbiology and research laboratories.
Methylene blue, catalogue No. M9140, is a certified biological stain supplied by MilliporeSigma / Merck. It is a phenothiazine dye with the empirical formula C16H18ClN3S · xH2O and a molecular weight of 319.85 g/mol (anhydrous basis). The powder has a dark green appearance and a dye content of ≥ 82 %, certified by the Biological Stain Commission (BSC) for quality and staining performance.
This dye is commonly used in microbiology and clinical laboratories for staining bacteria and tissues. It is suitable for bacteriologic staining methods such as Wright stain for blood smears and phloxine-methylene blue stains. The product is supplied as a powder and must be dissolved prior to use according to appropriate laboratory staining protocols.
Advantages
- Certified by the Biological Stain Commission (BSC) for consistent staining performance.
- High dye content (≥ 82 %) ensures reliable staining intensity.
- Phenothiazine-based dye suitable for multiple microbiological and histological staining methods.
- Supplied in stable powder form for long shelf life and controlled preparation.
Technical specifications
| Chemical name | Methylene blue |
| Grade / Certification | Certified by the Biological Stain Commission (BSC) |
| Dye content | ≥ 82 % |
| Empirical formula | C16H18ClN3S · xH2O |
| Molecular weight | 319.85 g/mol (anhydrous basis) |
| CAS number | 122965-43-9 |
| Form | Powder |
| Colour | Dark green powder |
| Solubility | Soluble in water (approx. 4 mg/4 mL), partially soluble in alcohol |
| Typical applications | Microbiology staining, clinical diagnostics, hematology, histology |
| Storage conditions | Room temperature, dry and tightly closed container |
| Brand | Merck |
