Toluidine Blue O
Toluidine Blue O (CAS: 92-31-9) is a thiazine dye with the molecular formula C15H16ClN3S and a molecular weight of 305.83 g/mol. This certified biological stain is widely recognised for its utility in histology and cell biology. It is supplied by Tech Serve Solutions as a powder with a dye content of at least 80%, meeting the stringent standards set by the Biological Stain Commission for reliable laboratory applications.
- IUPAC
- Basic Blue 17,Blutene chloride,Methylene Blue T50 or T extra,Tolonium chloride
- Synonyms
- Toluidine Blue OToluidine blue OCAS 92-31-9C.I. 52040Basic Blue 17Blutene chlorideMethylene Blue T50 or T extraTolonium chloride

Histological Staining
Toluidine Blue O is a crucial stain in histology for differential staining of tissues. It is particularly effective for visualising cell nuclei and mast cells within tissue samples, aiding in pathological diagnosis and research.
Cell Biology Research
In cell biology, this dye serves as a vital reagent for staining cellular components and evaluating cell viability. Its ability to bind with nucleic acids makes it valuable for microscopy and cytological studies.
Dye and Reagent Supply
As a certified stain, Toluidine Blue O is supplied for various laboratory applications where precise staining is required. It is a staple reagent in research and diagnostic laboratories globally.
| Molecular weight | 305.83 |
|---|---|
| Empirical formula | C15H16ClN3S |
| Grade | certified by the Biological Stain Commission |
| Form | powder |
| Solubility | H2O: soluble1 mg/mL |
| Composition | Dye content, 80% |
| Protective equipment | Eyeshields, Gloves, type N95 (US), type P1 (EN143) respirator filter |
|---|---|
| Water hazard class (WGK, DE) | 3 |
Hazard information is provided for guidance. Always consult the product Safety Data Sheet (SDS), available on request, before handling.
| Colour Index Number | 52040 |
|---|
Documentation
Every batch ships with a Certificate of Analysis covering assay, identity and purity; the grade is confirmed against your enquiry. Safety Data Sheets and technical data sheets are available on request.
Supply & logistics
Samples for technical evaluation; bulk MOQ by grade and packaging. In-stock material ships in 7–10 working days, worldwide, with full export documentation.
What is Toluidine Blue O used for?
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Toluidine Blue O is primarily used as a histological stain for differential staining of tissues, visualising cell nuclei and mast cells, and in cell biology research for staining cellular components and assessing cell viability.
What are the CAS number and formula for Toluidine Blue O?
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The CAS number for Toluidine Blue O is 92-31-9, and its molecular formula is C15H16ClN3S.
What grade and purity does Tech Serve Solutions supply?
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Tech Serve Solutions supplies Toluidine Blue O as a powder with a dye content of 80%, certified by the Biological Stain Commission. We do not represent this product as USP, BP, or EP grade.
How should Toluidine Blue O be handled safely?
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When handling Toluidine Blue O, appropriate personal protective equipment, including eyeshields, gloves, and a P1 (EN143) or N95 (US) respirator filter, should be used. The compound has a WGK Germany rating of 3, indicating it is hazardous to water.
How is Toluidine Blue O packed, shipped, and exported?
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Toluidine Blue O is carefully packed and prepared for shipment and export in compliance with all relevant regulations to ensure safe and secure delivery to our global customers.
How can I request a quote or sample for Toluidine Blue O?
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To request a quote or a sample of Toluidine Blue O, please contact our sales team through the website or by phone. Our representatives will be pleased to assist you with your specific requirements.
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