Molekula
Acid Red 388 liquid (Rhodamine WT 20% aqueous solution)
Supplying 4,500+ customers in over 80 countries
ISO 9001:2015 & ISO 14001:2015 certified · Supplying laboratories and industry since 2000 · Listed pack sizes are a starting point — we manufacture, source and repack to the quantity you need
Acid Red 388 liquid, also known as Rhodamine WT, is a water-soluble fluorescent dye primarily used in textile dyeing, paper manufacturing, and as a tracer in environmental studies. This 20% aqueous solution features a CAS number of 37299-86-8, with the molecular formula C29H29ClN2Na2O5 and a molecular weight of 566.99. It requires ambient storage conditions and carries no signal word for hazard classification. Molekula supplies Acid Red 388 liquid from research to bulk quantities with full documentation and ISO 9001:2015 traceability.
Example image for illustration only. Other packaging and pack sizes are available.
Pricing & pack sizes
These pack sizes aren't a limit. Molekula manufactures, sources and repacks to order — if you need 500 kg and only see 1 kg listed, . We quote from grams to multi-tonne.
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25 mL — £30.90 per pack ex VAT · £37.08 inc. VAT
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Specifications
| Property | Value |
|---|---|
| Appearance | Dark red liquid |
| pH | >10.00 |
| Assay | 19.37 - 23.03% |
| Colour Strength | 2.08 - 2.47 mg/100ml |
| Absorbance | 0.405 - 0.482 Abs |
Storage & handling
| Property | Value |
|---|---|
| Storage Temperature | Ambient |
| Acidity | Acid |
Identification
| Property | Value |
|---|---|
| SKU | 90028160 |
| CAS Number | 37299-86-8 |
| IUPAC Name | disodium;4-[3-(diethylamino)-6-diethylazaniumylidenexanthen-9-yl]benzene-1,3-dicarboxylate;chloride |
| Molecular Formula | C29H29ClN2Na2O5 |
| Molecular Weight | 566.99 |
| Exact Mass | 566.156 |
| SMILES | CCN(CC)C1=CC2=C(C=C1)C(=C3C=CC(=[N+](CC)CC)C=C3O2)C4=C(C=C(C=C4)C(=O)[O-])C(=O)[O-].[Na+].[Na+].[Cl-] |
| InChIKey | NRZDMKVYRRMFRR-UHFFFAOYSA-L |
| InChI | InChI=1S/C29H30N2O5.ClH.2Na/c1-5-30(6-2)19-10-13-22-25(16-19)36-26-17-20(31(7-3)8-4)11-14-23(26)27(22)21-12-9-18(28(32)33)15-24(21)29(34)35;;;/h9-17H,5-8H2,1-4H3,(H-,32,33,34,35);1H;;/q;;2*+1/p-2 |
| PubChem CID | 37718 |
| REACH Code | Y110 |
| Tariff Code | 32129000 |
Safety & GHS
Detailed safety information available in the SDS — see Documents below.
Documents
Safety Data Sheets (SDS)
Available in English, French, German, Italian, Russian, Spanish.
Certificate of Analysis (CoA) by batch
Enter a lot or batch number to retrieve the CoA for that specific batch. We can generate one from spec data if no PDF is on file.
Synonyms
- Acid Red 388
- C29H29ClN2Na2O5
- NRZDMKVYRRMFRR-UHFFFAOYSA-L
- RHODAMINE WT
- Sodium 4-(3,6-bis(diethylamino)xanthylium-9-yl)isophthalate chloride
Frequently asked questions
What is Acid Red 388 (Rhodamine WT) used for?
Acid Red 388 (Rhodamine WT) is a fluorescent water-tracing dye, used mainly as a hydrological and environmental tracer in flow, dispersion and dye-dilution studies.
What is the chemical formula and molecular weight of Acid Red 388?
The chemical formula is **C₂₉H₂₉ClN₂Na₂O₅**, and the molecular weight is **566.99 g/mol**.
How should Acid Red 388 be stored?
Store at **ambient temperature** in a tightly sealed container, protected from prolonged light exposure.
What grade or purity is available for Acid Red 388?
Molekula supplies Acid Red 388 as a **20% aqueous solution** with analytical-grade purity suitable for research applications.
Can Molekula supply Acid Red 388 in bulk quantities?
Yes, bulk quantities are available upon request—contact our sales team for custom packaging and pricing.
What documentation comes with an order of Acid Red 388?
Each order includes a **Certificate of Analysis (CoA)**, Material Safety Data Sheet (MSDS), and batch-specific documentation.
Ready to order or need a custom pack?
Tell us the product, grade, and quantity — Molekula usually responds within one working day with pricing and lead time.