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We can only ship non-hazardous products to Rest of World

Methyl Red Sodium Salt C.I. 13020

Price: £14.04
Stock Availability:

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Stock Availability
On Shelf - Approx. UK delivery date: Wednesday the 01st October 2025*
In bulk stock - ships within 10 - 12 Working Days (Excluding weekends and public holidays)
4 to 6 weeks approx. (Not guaranteed)
UK Shipping

Unfortunately, we are not currently accepting orders for Northern Ireland.

We can only ship to the following postcodes where a Royal Mail postal option has been chosen at checkout.

AB, DD, DG3, DG4, DG6 - DG9, EH, FK, G, HS, IM, IV, KA, KW, KY, ML, PA, PH, PO30 - PO41, TD, TR21 - TR25, ZE

* We will always try to ship as early as possible. Delivery could be much quicker than stated but is not guaranteed
  • pH Indicator
  • Identification of bacteria in Microbiology

Methyl Red sodium salt is the sodium salt of Methyl Red. Methyl red is an indicator dye that turns red in acidic solutions. It is a pH indicator, turning red under pH 4.4, yellow over pH 6.2, and orange in between those values. It is used in microbiology in the Voges-Proskauer test to identify bacteria that produce stable acids through mixed acid fermentation of glucose. Methyl-red positive bacteria include Proteus vulgaris and Escherichia coli. Methyl-red negative bacteria include Enterobacter aerogenes and Serratia marcescens.

C.I.13020

  • Dye Content: >90%
  • Molecular Formula: C15H14N3NaO3
  • Molecular Weight: 291.29 g/mol
  • Transition Range: pH4.2 (Violet Red) - pH6.2 (Brownish/Yellow)
  • Maximum Absorption (pH4.2): 523-527nm
  • Maximum Absorption (pH6.2): 430-434nm
  • Absorptivity(A1%/1cm@pH4.2): 1200-1300
  • Absorptivity(A1%/1cm@pH4.2): 675-735
  • Loss on Drying: <5%

Hazard Phrases: Not considered harmful under normal laboratory conditions

Cas No: 845-10-3
Einecs No: 212-682-9

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Source Chemicals Ltd