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105945

Sigma-Aldrich

Phenolphthalein

ACS reagent

Synonym(s):

3,3-Bis(4-hydroxyphenyl)-1(3H)-isobenzofuranone

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5 MG
CN¥1,029.74

About This Item

Empirical Formula (Hill Notation):
C20H14O4
CAS Number:
77-09-8
Molecular Weight:
318.32
Colour Index Number:
764
Beilstein:
284423
EC Number:
201-004-7
MDL number:
MFCD00005913
UNSPSC Code:
12171500
PubChem Substance ID:
24846716
NACRES:
NA.47

CN¥1,029.74

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grade

ACS reagent

Quality Level

200

form

powder

technique(s)

titration: suitable

visual transition interval

8.0-10, colorless to red

mp

261-263 °C (lit.)

solubility

acetone: soluble

density

1.27 g/cm3 at 32 °C

λmax

374 nm (2nd)
552 nm

application(s)

diagnostic assay manufacturing
hematology
histology

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Corning® microvolume pipet tips 0.1-10 μL, universal fit racked pipet tips, natural, sterile, 96 tips/rack, 960tips/case

CLS4894

Corning® microvolume pipet tips

Corning® microvolume pipet tips 0.5-10 μL, universal fit racked pipet tips, natural, sterile, 96 tips/rack, 960 tips/case

CLS4830

Corning® microvolume pipet tips

Corning® microvolume pipet tips 0.5-10 μL, universal fit racked pipet tips, natural, non-sterile, 96 tips/rack, 960 tips/case

CLS4834

Corning® microvolume pipet tips

Corning® microvolume pipet tips 0.1-10 μL, universal fit racked pipet tips, natural, non-sterile, 96 tips/rack, 960tips/case

CLS4826

Corning® microvolume pipet tips

sterility

sterile

sterility

sterile

sterility

non-sterile

sterility

non-sterile

manufacturer/tradename

Corning 4894

manufacturer/tradename

Corning 4830

manufacturer/tradename

Corning 4834

manufacturer/tradename

Corning 4826

material

natural tip, polypropylene

material

natural tip, polypropylene

material

natural tip, polypropylene

material

natural tip, polypropylene

packaging

rack of 96

packaging

rack of 96

packaging

rack of 96

packaging

rack of 96

volume range

0.1-10 μL

volume range

0.5-10 μL

volume range

0.5-10 μL

volume range

0.1-10 μL

General description

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.

Application

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 Actions

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

Principle

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]

Pictograms

Health hazardExclamation mark
GHS08,GHS07

Signal Word

Danger

Hazard Statements

H315,H341,H350,H361f

Hazard Classifications

Carc. 1B - Muta. 2 - Repr. 2 - Skin Irrit. 2

Storage Class Code

6.1C - Combustible acute toxic Cat.3 / toxic compounds or compounds which causing chronic effects

WGK

WGK 3

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

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    Certificates of Analysis (COA)

    Lot/Batch Number
    BCCM7361
    BCCL3444
    BCCK1147
    MKCT3743
    MKCR8728

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    Find documentation for the products that you have recently purchased in the Document Library.

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    Conn?s Biological Stains: A Handbook of Dyes, Stains and Fluorochromes for Use in Biology and Medicine (10th ed.)
    RW Horobin, JW Kiernan (Eds.)
    Conn?s Biological Stains (2002)
    Using phenolphthalein as a promising indicator to monitor the vacuum freeze-drying process
    Liu, et al.
    Materials Letters, 139 (2015)
    The experimental investigation of concrete carbonation depth
    Cheng-Feng Chang, Jing-Wen Chen
    Cement and Concrete Research, 36(9) (2006)
    Teaching New Tricks to an Old Indicator: pH-Switchable, Photoactive Microporous Polymer Networks from Phenolphthalein with Tunable CO2 Adsorption Power
    Kiskan, et al.
    Macromolecules (2012)
    Min Guk Kim et al.
    Journal of personalized medicine, 10(4) (2020-10-15)
    Unbalanced dietary habits and the consumption of high protein and instant foods cause an increase in constipation. Here, we evaluated the effects of galacto-oligosaccharide (GOS) on a rat model of loperamide-induced constipation by measuring various biological markers and cecal microbiota.
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