Thymol blue

    WARNING: This product is for research use only, not for human or veterinary use.

MedKoo CAT#: 464075

CAS#: 76-61-9

Description: Thymol blue (thymolsulfonephthalein) is a brownish-green or reddish-brown crystalline powder that is used as a pH indicator. It is insoluble in water but soluble in alcohol and dilute alkali solutions. It transitions from red to yellow at pH 1.2–2.8 and from yellow to blue at pH 8.0–9.6. It is usually a component of Universal indicator. At wavelength (378 - 382) nm, extinction coefficient > 8000 and at wavelength (298 - 302) nm , the extinction coefficient > 12000.

Chemical Structure

Thymol blue
CAS# 76-61-9

Theoretical Analysis

MedKoo Cat#: 464075
Name: Thymol blue
CAS#: 76-61-9
Chemical Formula: C27H30O5S
Exact Mass: 466.1814
Molecular Weight: 466.592
Elemental Analysis: C, 69.50; H, 6.48; O, 17.14; S, 6.87

Price and Availability

Size Price Availability Quantity
5.0g USD 220.0 2 Weeks
25.0g USD 410.0 2 Weeks
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Synonym: Thymol blue; NSC 11238; NSC11238; NSC-11238; Thymolsulfonephthalein;

IUPAC/Chemical Name: 3,3-bis(4-hydroxy-5-isopropyl-2-methylphenyl)-3H-benzo[c][1,2]oxathiole 1,1-dioxide


InChi Code: InChI=1S/C27H30O5S/c1-15(2)19-13-22(17(5)11-24(19)28)27(21-9-7-8-10-26(21)33(30,31)32-27)23-14-20(16(3)4)25(29)12-18(23)6/h7-16,28-29H,1-6H3

SMILES Code: CC(c1c(O)cc(C)c(C2(c3c(C)cc(O)c(C(C)C)c3)OS(=O)(c4c2cccc4)=O)c1)C

Appearance: Solid powder

Purity: >98% (or refer to the Certificate of Analysis)

Shipping Condition: Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition: Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).

Solubility: Soluble in DMSO

Shelf Life: >2 years if stored properly

Drug Formulation: This drug may be formulated in DMSO

Stock Solution Storage: 0 - 4 C for short term (days to weeks), or -20 C for long term (months).

HS Tariff Code: 2934.99.9001

Preparing Stock Solutions

The following data is based on the product molecular weight 466.592 Batch specific molecular weights may vary from batch to batch due to the degree of hydration, which will affect the solvent volumes required to prepare stock solutions.

Recalculate based on batch purity %
Concentration / Solvent Volume / Mass 1 mg 5 mg 10 mg
1 mM 1.15 mL 5.76 mL 11.51 mL
5 mM 0.23 mL 1.15 mL 2.3 mL
10 mM 0.12 mL 0.58 mL 1.15 mL
50 mM 0.02 mL 0.12 mL 0.23 mL

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Thymol blue

10.0mg / Not available