Molekula
Bromothymol Blue
Supplying 4,500+ customers in over 80 countries
ISO 9001:2015 & ISO 14001:2015 certified · Supplying laboratories and industry since 1999 · Listed pack sizes are a starting point — we manufacture, source and repack to the quantity you need
Bromothymol Blue is a pH-sensitive dye used as an indicator in acid-base titrations, biological staining, and environmental testing to visually assess pH levels between 6.0 and 7.6, shifting from yellow to blue. It appears as a pink, purple or brown powder with a molecular formula of C27H28Br2O5S and a molecular weight of 624.38 g/mol. Stable at ambient conditions, it requires no special signal warnings.
Molekula supplies Bromothymol Blue in 25 g packs, from £92.76 inc. VAT. It is in stock for same-day dispatch. Every batch ships with a certificate of analysis, and safety data sheets are available in 5 languages. Larger quantities, up to multi-tonne, are quoted on request.
Example image for illustration only. Other packaging and pack sizes are available.
Often bought together
Pricing & pack sizes
In stock — same-day dispatch
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.
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25 g — £77.30 per pack ex VAT · £92.76 inc. VAT
Need a different quantity or pack?
Tell us how much you need and when — drums, IBCs, sacks or a one-off bulk lot. We'll manufacture or source it and come back with a price.
Prices exclude VAT/sales tax and shipping.
Specifications
| Property | Value |
|---|---|
| Appearance | Pink/Purple/Brown powder |
| Loss on Drying | ≤ 3% |
| Dye Content | ≥95% |
| Transition Range | pH 5.8 - 7.6 Yellow - Blue |
| Solubility at 0.1% (95% Ethanol) | Clear Solution |
| Wavelength of maximum absorption(pH 5.8) λ1 max | 430 - 435 nm |
| Wavelength of maximum absorption (pH 7.6) λ2 max | 615 - 618 nm |
| Absorptivity (E 1% in 1cm cell at λ1 max),pH 5.8 | 260 - 300 |
| Absorptivity (E 1% in 1cm cell at λ2 max),pH 7.6 | 470 - 520 |
Storage & handling
| Property | Value |
|---|---|
| Storage Temperature | Ambient |
| Acidity | Neutral |
Identification
| Property | Value |
|---|---|
| SKU | 35458451 |
| CAS Number | 76-59-5 |
| IUPAC Name | 2-bromo-4-[3-(3-bromo-4-hydroxy-2-methyl-5-propan-2-ylphenyl)-1,1-dioxo-2,1lambda6-benzoxathiol-3-yl]-3-methyl-6-propan-2-ylphenol |
| EC Number | 200-971-2 |
| Molecular Formula | C27H28Br2O5S |
| Molecular Weight | 624.38 |
| Exact Mass | 624.0004 |
| SMILES | CC1=C(C=C(C(=C1Br)O)C(C)C)C2(C3=CC=CC=C3S(=O)(=O)O2)C4=C(C(=C(C(=C4)C(C)C)O)Br)C |
| InChIKey | NUHCTOLBWMJMLX-UHFFFAOYSA-N |
| InChI | InChI=1S/C27H28Br2O5S/c1-13(2)17-11-20(15(5)23(28)25(17)30)27(19-9-7-8-10-22(19)35(32,33)34-27)21-12-18(14(3)4)26(31)24(29)16(21)6/h7-14,30-31H,1-6H3 |
| PubChem CID | 6450 |
| REACH Code | Y113 |
| TSCA Listed | Yes |
| HTS Code | 29349944 |
| Tariff Code | 2934999090 |
Safety & GHS
Precautionary statements
- P280 Wear protective gloves/protective clothing/eye protection/face protection
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.
Quality certificates
Molekula Group is certified to ISO 9001:2015 (quality) and ISO 14001:2015 (environmental management), audited by a UKAS-accredited body. Both certificates are valid to 17 May 2028.
Synonyms
- 3,3'-Dibromothymolsulfonphthalein
- Blue, Bromothymol
- Blue, Bromthymol
- Bromothymol blue (sodium salt)
- BROMTHYMOL BLUE
- Bromthymolblau
- C27H28Br2O5S
- Dibromothymolsulfonphthalein
- Dibromothymolsulfophthalein
- Thymol, 6,6'-(3H-2,1-benzoxathiol-3-ylidene)bis(2-bromo-, S,S-dioxide
Frequently asked questions
What is Bromothymol Blue commonly used for?
Bromothymol Blue is primarily used as a pH indicator in laboratories, turning yellow in acidic solutions, blue in basic solutions, and green at neutral pH (~6.0–7.6). It is also used in biological buffers and as a dye in microscopy.
What is the chemical formula and molecular weight of Bromothymol Blue?
The chemical formula is C₂₇H₂₈Br₂O₅S, and the molecular weight is 624.38 g/mol.
How should Bromothymol Blue be stored?
Store at ambient temperature in a tightly sealed container, away from direct sunlight and moisture.
What grades of Bromothymol Blue does Molekula supply?
Molekula supplies Bromothymol Blue with a dye content of at least 95%, suitable for laboratory and research applications.
Can Molekula supply Bromothymol Blue in bulk quantities?
Yes, we offer bulk packaging options for Bromothymol Blue—please contact our sales team for custom quantities and pricing.
What documentation comes with an order of Bromothymol Blue?
Each order includes a Certificate of Analysis (CoA), Material Safety Data Sheet (MSDS), and batch-specific documentation for traceability.
Where can I buy Bromothymol Blue?
Directly from Molekula, which lists Bromothymol Blue in 25 g packs from £92.76 inc. VAT, with a certificate of analysis for every batch. Larger quantities are quoted on request. Molekula's offices: United Kingdom, France, Spain, Germany, Italy, United States and China.
Ready to order or need a custom pack?
Tell us the product, grade, and quantity — Molekula usually responds within one working day with pricing and lead time.