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Status: Currently O

cial on 17-Feb-2025

O

cial Date: O

cial Prior to 2013

Document Type: Reagents

DocId: GUID-3B79530B-468E-4374-9351-4837C76DB17B_1_en-US

DOI: https://doi.org/10.31003/USPNF_R3053_01_01

DOI Ref: ve70s

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Thymol Blue

(Thymolsulfonphthalein), C H O S—466.59—Dark-colored, crystalline powder. Slightly soluble in water; soluble in alcohol and in dilute alkali

solutions. Acid—Transition interval: from pH 1.2 to 2.8. Color change: from red to yellow. Alkaline—Transition interval: from pH 8.0 to 9.2. Color

change: from yellow to blue.

Auxiliary Information - Please check for your question in the FAQs before contacting USP.

Topic/Question Contact Expert Committee

THYMOL BLUE Margareth R.C. Marques

Principal Scienti

c Liaison HDQ Headquarters

Most Recently Appeared In:

Pharmacopeial Forum: Volume No. Information currently unavailable

Current DocID: GUID-3B79530B-468E-4374-9351-4837C76DB17B_1_en-US

DOI: https://doi.org/10.31003/USPNF_R3053_01_01

DOI ref: ve70s

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2/17/25, 12:25 AM USP-NF Thymol Blue

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