114529

Phenol Red

ACS reagent

• Synonym(s): Phenolsulfonphthalein
• Empirical Formula (Hill Notation): C₁₉H₁₄O₅S
• CAS Number: 143-74-8
• Molecular Weight: 354.38
• Beilstein: 326470
• EC Number: 205-609-7
• MDL number: MFCD00003552
• UNSPSC Code: 12171500
• PubChem Substance ID: 24847179
• NACRES: NA.47

Properties

• grade: ACS reagent
• Quality Level: 200
• form: powder
• clarity of soln: passes test
• technique(s): titration: suitable
• visual transition interval: 6.8-8.2, yellow to red
• solubility: water: 0.77 g/L at 100 °C
• λmax: 360 nm; 557 nm (2nd)
• ε (extinction coefficient): ≥10000 at 288-294 nm in H₂O; ≥55000 at 555-561 nm in H₂O; ≥7000 at 357-363 nm in H₂O
• application(s): diagnostic assay manufacturing; hematology; histology
• storage temp.: room temp
• SMILES string: Oc1ccc(cc1)C2(OS(=O)(=O)c3ccccc23)c4ccc(O)cc4
• InChI: 1S/C19H14O5S/c20-15-9-5-13(6-10-15)19(14-7-11-16(21)12-8-14)17-3-1-2-4-18(17)25(22,23)24-19/h1-12,20-21H
• InChI key: BELBBZDIHDAJOR-UHFFFAOYSA-N

Description

General description

Phenol Red is a phenolsulfonphthalein compound. It is present as a sulfonated hydroxyquinone in weakly acidic aqueous solutions. In alkaline solutions, the dye forms a hydrophilic dianion (a small, red anion that has a larger conjugated system than the yellow hydroxyquinone).

Application

Phenol red is commonly used as a pH indicator in biology and medicine. It is incorporated into microbiological culture media for the identification of Escherichia coli strains. Its clinical diagnostic applications include the investigation of gastric and duodenal ulcers and the assessment of tear function in ophthalmology. Phenol red is also used as a tracer to assess the permeability of the ileal mucosal membrane and to assess bacterial leakage through root-filling materials in dentistry.
Phenol Red has been used for the preparation of phenol red gavage meal for measurement of gastric emptying in rats.

Suitable for use as a pH indicator.

Biochem/physiol Actions

Phenol Red is a pH indicator which changes color from yellow to red.

Safety Information

• Pictograms: GHS07
• Signal Word: Warning
• Hazard Statements: H315,H335
• Precautionary Statements: P261 - P264 - P271 - P280 - P302 + P352 - P304 + P340 + P312
• Hazard Classifications: Skin Irrit. 2 - STOT SE 3
• Target Organs: Respiratory system
• Storage Class Code: 11 - Combustible Solids
• WGK: WGK 3
• Flash Point(F): Not applicable
• Flash Point(C): Not applicable
• Personal Protective Equipment: dust mask type N95 (US), Eyeshields, Gloves