Sudan III C.I.26100


Sudan III is a red brown powder and is often used to demonstrate triglycerides in frozen sections. It is also known as Solvent Red 23.

  • Used as a biological stain

It is used to colour nonpolar substances such as oils, fats, waxes, greases, various hydrocarbon products. It is a replacement for Solvent Red 26 with better solubility in hydrocarbons. The IRS requires a concentration spectrally equivalent to at least 3.9 pounds of Solvent Red 26 per thousand barrels of fuel” (11.1 mg/l); the concentrations required by EPA are roughly 5 times lower.

C.I. 26100
Dye Content: >85%
Molecular Formula: C22H16N4O
Molecular Weight: 352.39 g/mol
Melting Point: 199 °C (lit.)

Hazard Phrases: Causes skin irritation. Causes serious eye irritation. May cause respiratory irritation.

Prec Phrases: Avoid breathing dust/fume/gas/mist/vapours/spray. IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing. Wear protective gloves/protective clothing/eye protection/face protection.

Cas No: 85-86-9
Einecs No: 201-638-4

HS CODE: 32129000


Following the UK’s departure from the EU on 1 January 2021, all European shipments are sent on a DAP Basis (Delivered at Place).

This means that the buyer will be liable for import VAT at their prevailing national rate and for orders over 150€ (including carriage) import duties will become chargeable at your prevailing national rate.

The Duty is ascertained by your national customs authority based on the HS Code of each product. The HS Code is shown in the “European Shipment” section of each product page.



Additional information

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10gm, 25gm, 50gm, 100gm