Thymol blue
Based on 1 Customer Validation
Thymol blue is a reversible pH indicator that responds to the pH of the solution through structural changes of protonation and deprotonation. Thymol blue is red (HI- form) under acidic conditions and blue (I2- form) under alkaline conditions. Quantitative detection is achieved through the absorption peak shift (435 nm/596 nm) of the UV-visible spectrum. Thymol blue selectively responds to pH changes, changing from red to yellow at pH 1.2-2.8 and from yellow to blue at pH 8.0-9.6. Thymol blue can be fixed in a silica gel matrix through sol-gel technology to form a solid-state sensor for in-situ pH measurement in the marine environment and acid-base monitoring in the biomedical field[1][2].
For research use only. We do not sell to patients.
- CAS No.: 76-61-9
- Formula: C27H30O5S
- Molecular Weight:466.59
-
Storage:
4°C, protect from light
* In solvent : -80°C, 6 months; -20°C, 1 month (protect from light)
Biological Activity
Guide (The following is our recommended experimental protocol. This protocol is for reference only and should be modified according to your specific needs).
Thymol blue acid-base indicator protocol (solution state)[1]:
1. Solution preparation
Dissolve Thymol blue sodium salt in ethanol (or water/ethanol mixed solvent) to prepare a 0.1% (w/v) stock solution.
2. pH response test
Take the solution to be tested and add 1-2 drops of Thymol blue indicator:
Acidic conditions (pH<1.7) The solution turns red (HI- form).
Neutral to weakly alkaline (1.7≤pH≤8.9: the solution is yellow (intermediate state.
Strongly alkaline (pH>8.9): the solution is blue (I2- form).
3. Quantitative detection
Use a spectrophotometer to measure the absorbance at 435 nm (HI-) and 596 nm (I2-), calculate the ratio R=A596/A435, and calculate the pH value using the ionization formula.
MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.
Chemical Information
-
CAS No. 76-61-9
-
Appearance Solid
-
Molecular Weight 466.59
-
Formula C27H30O5S
-
SMILES
O=S1(OC(C2=C(C)C=C(O)C(C(C)C)=C2)(C3=C(C)C=C(O)C(C(C)C)=C3)C4=CC=CC=C41)=O
-
Synonyms
Thymolsulphonephthalein
-
Shipping
Room temperature in continental US; may vary elsewhere.
-
Storage
4°C, protect from light
* In solvent : -80°C, 6 months; -20°C, 1 month (protect from light)
Purity & Documentation
-
Data Sheet (280 KB)
-
SDS (393 KB)
- English - EN (393 KB)
- Français - FR (393 KB)
- Deutsch - DE (393 KB)
- Norwegian - NO (393 KB)
- Español - ES (393 KB)
- Swedish - SV (393 KB)
- Italian - IT (393 KB)
- Korean - KR (393 KB)
- Portuguese - PT (393 KB)
-
Handling Instructions (2659 KB)
References
Calculators
Concentration (start) × Volume (start) = Concentration (final) × Volume (final)