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Supelco

Phenol red

pH indicator, ACS

Synonym(s):

Phenol red

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5 G
$120.00
25 G
$300.00
100 G
$735.00
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$7,500.00

$120.00


Estimated to ship onMay 11, 2025


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5 G
$120.00
25 G
$300.00
100 G
$735.00
1 KG
$7,500.00

About This Item

Linear Formula:
(C6H4OH)2C7H4SO3
CAS Number:
Molecular Weight:
354.38
MDL number:
UNSPSC Code:
12171502
EC Index Number:
205-609-7
NACRES:
NA.21

$120.00


Estimated to ship onMay 11, 2025


Request a Bulk Order

Product Name

Phenol red, indicator ACS

grade

ACS reagent

Quality Level

form

solid

loss

≤1% loss on drying, 110°C

visual transition interval

1.2-3.0, brown-orange to yellow(1st transition range)
6.5-8.0, brownish-yellow to red-violet(2nd transition range)

mp

>300 °C

bulk density

200‑300 kg/m3

storage temp.

2-30°C

SMILES string

[S]1(=O)(=O)OC(c4c1cccc4)(c3ccc(cc3)O)c2ccc(cc2)O

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

General description

Phenol red (phenolsulfonphthalein, PH R) belongs to the class of triphenylmethane dyes. It is a waterͰsoluble anionic dye, mostly used as a pH indicator in cell biology laboratories. Also, in different protocols, it is used to detect H2O2(Hydrogen peroxide).

Application

Phenol red can be used as a:
  • Dye in the preparation of phenol red/n-Si photodiode [phenol red/n-type silicon wafer] by spin coating technique. The device is appropriate for photo-detection applications.
  • Color-changing dye in the design of fiber optic pH sensor because as the acidity increases, the dye′s absorption properties shift from the green to the blue section of the spectrum.
  • Indicator in the determination of freshwater pH.

Features and Benefits

Phenol red is used to detect pH changes in cell culture,
  • pH is 6.4 or below yellow color
  • pH is 8.2 or above red color.

Analysis Note

Appearance of solution: passes test
1st transition range: pH 1.2 - pH 3.0brownish orange - yellow
2nd transition range: pH 6.5 - pH 8.0brownish yellow - red violet
Loss on drying (110 °C): ≤ 1
Transition range (according to ACS): passes test
ACS conforms

pictograms

Exclamation mark

signalword

Warning

Hazard Classifications

Skin Irrit. 2 - STOT SE 3

target_organs

Respiratory system

Storage Class

11 - Combustible Solids

wgk_germany

WGK 3

flash_point_f

Not applicable

flash_point_c

Not applicable


Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

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Questions

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  1. How is shipping temperature determined? And how is it related to the product storage temperature?

    1 answer
    1. Products may be shipped at a different temperature than the recommended long-term storage temperature. If the product quality is sensitive to short-term exposure to conditions other than the recommended long-term storage, it will be shipped on wet or dry-ice. If the product quality is NOT affected by short-term exposure to conditions other than the recommended long-term storage, it will be shipped at ambient temperature. As shipping routes are configured for minimum transit times, shipping at ambient temperature helps control shipping costs for our customers. For more information, please refer to the Storage and Transport Conditions document: https://www.sigmaaldrich.com/deepweb/assets/sigmaaldrich/marketing/global/documents/316/622/storage-transport-conditions-mk.pdf

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  2. How can I determine the shelf life / expiration / retest date of this product?

    1 answer
    1. If this product has an expiration or retest date, it will be shown on the Certificate of Analysis (COA, CofA). If there is no retest or expiration date listed on the product's COA, we do not have suitable stability data to determine a shelf life. For these products, the only date on the COA will be the release date; a retest, expiration, or use-by-date will not be displayed.
      For all products, we recommend handling per defined conditions as printed in our product literature and website product descriptions. We recommend that products should be routinely inspected by customers to ensure they perform as expected.
      For products without retest or expiration dates, our standard warranty of 1 year from the date of shipment is applicable.
      For more information, please refer to the Product Dating Information document: https://www.sigmaaldrich.com/deepweb/assets/sigmaaldrich/marketing/global/documents/449/386/product-dating-information-mk.pdf

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