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250198

Sigma-Aldrich

Methyl Red

ACS reagent, crystalline

Synonym(s):

2-(4-Dimethylaminophenylazo)benzoic acid, 4-Dimethylaminoazobenzene-2′-carboxylic acid, Acid Red 2

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1 ML
$206.00
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$226.00
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$653.00
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$786.00
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$1,040.00

$206.00

Estimated to ship onMay 29, 2025

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1 ML
$206.00
0.1 ML
$226.00
0.5 ML
$653.00
7 ML
$786.00
1 ML
$1,040.00

About This Item

Linear Formula:
(CH3)2NC6H4N=NC6H4CO2H
CAS Number:
493-52-7
Molecular Weight:
269.30
Colour Index Number:
13020
Beilstein/REAXYS Number:
750102
EC Number:
207-776-1
MDL number:
MFCD00002425
UNSPSC Code:
12171500
PubChem Substance ID:
24855040
NACRES:
NA.47

$206.00

Estimated to ship onMay 29, 2025

Request a Bulk Order

grade

ACS reagent

Quality Level

200

form

crystalline

technique(s)

titration: suitable

visual transition interval

4.2-6.2, pink to yellow

mp

179-182 °C (lit.)

solubility

ethanol: 1 mg/mL

λmax

410 nm

application(s)

diagnostic assay manufacturing
hematology
histology

storage temp.

room temp

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Ribonucleic acid from torula yeast Type VI

R6625

Ribonucleic acid from torula yeast

Ribonucleic acid from torula yeast core, Type II-C

R6875

Ribonucleic acid from torula yeast

Ribonucleic acid diethylaminoethanol salt Type IX

R3629

Ribonucleic acid diethylaminoethanol salt

Ribonucleic acid from baker’s yeast (S. cerevisiae)

R6750

Ribonucleic acid from baker′s yeast (S. cerevisiae)

storage temp.

−20°C

storage temp.

−20°C

storage temp.

2-8°C

storage temp.

−20°C

type

Type VI

type

Type II-C

type

Type IX

type

-

Application

Methyl Red has been used as pH indicator in a glucose biosensor, which is used for salivary analysis.[1]

Biochem/physiol Actions

Methyl Red is a maroon red crystal azo dye.[2] Methyl Red is a pH indicator and changes color at a pH of 5.5.[3] Methyl Red is widely used in saliva sampling method. In addition, it is also employed in carbohydrate and lactic acid detection.[2] Methyl Red has been effectively used for intrageneric differentiation of Enterobacteriaceae.[4]

Storage Class

11 - Combustible Solids

wgk_germany

WGK 2

flash_point_f

Not applicable

flash_point_c

Not applicable

ppe

Eyeshields, Gloves, type N95 (US)

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    Certificates of Analysis (COA)

    Lot/Batch Number
    SHBP7169
    MKCJ9464
    MKCJ9462
    MKCF4128
    MKBZ8656V

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    R R colwell and R grigorova
    Methods in Microbiology, 19 (1987)
    A paper strip based non-invasive glucose biosensor for salivary analysis.
    Soni A
    Biosensors And Bioelectronics, 67, 763-768 (2015)
    R. W. Sabnis
    Handbook of Acid-Base Indicators (2007)
    An improved dithizone method for the determination of small quantities of zinc in blood and tissue samples.
    Vallee BL and Gibson JG 2nd
    The Journal of Biological Chemistry, 176, 435-443 (1948)
    X D Zhang et al.
    Journal of hazardous materials, 170(2-3), 883-887 (2009-06-09)
    An aqueous C.I. Acid Red 2 solution was decolorized by electrolysis using iron as anode. The decolorization mechanism was investigated through experimental observations on the electrochemical behavior of C.I. Acid Red 2 on Pt rotating disk electrode, UV-visible spectra of
    View All Related Papers

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