105945

Phenolphthalein

ACS reagent

• Synonym(e): 3,3-Bis-(4-hydroxyphenyl)-1(3H)-isobenzofuranon
• Empirische Formel (Hill-System): C₂₀H₁₄O₄
• CAS-Nummer: 77-09-8
• Molekulargewicht: 318.32
• Farbindexnummer: 764
• Beilstein: 284423
• EG-Nummer: 201-004-7
• MDL-Nummer: MFCD00005913
• UNSPSC-Code: 12171500
• PubChem Substanz-ID: 24846716
• NACRES: NA.47

Eigenschaften

• Qualität: ACS reagent
• Qualitätsniveau: 200
• Form: powder
• Methode(n): titration: suitable
• visual transition interval: 8.0-10, colorless to red
• mp (Schmelzpunkt): 261-263 °C (lit.)
• Löslichkeit: acetone: soluble
• Dichte: 1.27 g/cm³ at 32 °C
• λmax: 374 nm (2nd); 552 nm
• Anwendung(en): diagnostic assay manufacturing; hematology; histology
• Lagertemp.: room temp
• SMILES String: Oc1ccc(cc1)C2(OC(=O)c3ccccc23)c4ccc(O)cc4
• InChI: 1S/C20H14O4/c21-15-9-5-13(6-10-15)20(14-7-11-16(22)12-8-14)18-4-2-1-3-17(18)19(23)24-20/h1-12,21-22H
• InChIKey: KJFMBFZCATUALV-UHFFFAOYSA-N

Beschreibung

Allgemeine Beschreibung

Phenolphthalein is an indicator for acid-base titration reactions.[1] It changes from colorless to violet-red between pH 8.3-9.8, it is red in extremely acidic solutions, and colorless in extremely alkaline solutions.[2]

It is present as a nonionic, lipophilic lactone in aqueous neutral solutions. It exists as a hydrophilic dianion in alkaline solutions.

Anwendung

Phenolphthalein has been commonly used as an indicator in the fields of biology and medicine. Its applications include:

• the development of novel technique to monitor the vacuum freeze-drying process[3]
• the determination of the depth of carbonation in concrete[4]
• the utilization of liquid marbles to sense gaseous environmental components
• the estimation of total acidity in vinegar
• the assessment of sodium hydroxide penetration into potatoes following chemical peeling
• as a model organic compound in the evaluation of the capture efficiency of various cyclodextrin constructs such as nanofiber-CD

Biochem./physiol. Wirkung

Phenolphthalein is colorless in acidic solutions and turns pink in basic solutions.

Phenolphthalein undergoes structural modification when there is a change in pH or in the structural state of water.[1] It is a nonionic, lipophilic colorless lactone in aqueous neutral solutions and a hydrophilic dianion in alkaline solutions.[2]

Sicherheitshinweise

• Piktogramme: GHS08,GHS07
• Signalwort: Danger
• H-Sätze: H315,H341,H350,H361f
• P-Sätze: P202 - P264 - P280 - P302 + P352 - P308 + P313 - P332 + P313
• Gefahreneinstufungen: Carc. 1B - Muta. 2 - Repr. 2 - Skin Irrit. 2
• Lagerklassenschlüssel: 6.1C - Combustible acute toxic Cat.3 / toxic compounds or compounds which causing chronic effects
• WGK: WGK 3
• Flammpunkt (°F): Not applicable
• Flammpunkt (°C): Not applicable
• Persönliche Schutzausrüstung: Eyeshields, Gloves, type P3 (EN 143) respirator cartridges