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114472

Cresol red

indicator grade, Dye content 95 %

Synonym(s):

o-Cresolsulfonphthalein

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About This Item

Empirical Formula (Hill Notation):
C21H18O5S
CAS Number:
1733-12-6
Molecular Weight:
382.43
UNSPSC Code:
12171500
NACRES:
NA.47
PubChem Substance ID:
24847173
EC Number:
217-064-2
Beilstein/REAXYS Number:
343399
MDL number:
MFCD00005878
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grade

indicator grade

Quality Segment

200

form

powder or crystals

composition

Dye content, 95%

technique(s)

titration: suitable

color

red-brown

pH

7.2-8.8, yellow to red

useful pH range

1.8-2.0, orange to yellow(acid), 7.0-8.8, yellow to violet(alkaline)

mp

290 °C

density

0.998 g/cm3

λmax

367 nm (2nd), 570 nm

application(s)

diagnostic assay manufacturing
hematology
histology

storage temp.

room temp

SMILES string

Cc1cc(ccc1O)C2(OS(=O)(=O)c3ccccc23)c4ccc(O)c(C)c4

InChI

1S/C21H18O5S/c1-13-11-15(7-9-18(13)22)21(16-8-10-19(23)14(2)12-16)17-5-3-4-6-20(17)27(24,25)26-21/h3-12,22-23H,1-2H3

InChI key

OBRMNDMBJQTZHV-UHFFFAOYSA-N

General description

Cresol Red, also known as o-cresol red, belongs to the phthalein and sulphonphthalein group of dyes. Cresol red changes color from orange to yellow at pH between 0.2-1.8 and yellow to violet at pH between 7.0-8.8. In alkaline solutions, cresol red is present as a hydrophilic dianion. The dianion is small and is violet in color, possessing a larger conjugated system than the yellow hydroxyquinone.

Application

Cresol Red is a widely used pH indicator for routine pH assessments like microbial culture media preparations. In addition, Cresol red is a suitable constituent of PCR reagent systems. Cresol Red is used as a tracking dye in DNA, RNA (agarose), and protein (polyacrylamide) electrophoresis.

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Storage Class

11 - Combustible Solids

wgk

WGK 3

ppe

dust mask type N95 (US), Eyeshields, Gloves

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