Molekula
Acid Red 388 (Rhodamine WT)
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, also called Rhodamine WT, is a fluorescent dye used mainly as a water tracer in hydrology, including groundwater and surface-water flow studies and dye-dilution measurements. It emits bright orange fluorescence under green excitation, making it ideal for sensitive detection applications. This chemical has a CAS number of 37299-86-8, with the molecular formula C29H29N2O5•Cl•Na2 and a molecular weight of 566.98. It is stable at ambient storage conditions but requires careful handling, as indicated by its "Warning" signal word. Molekula supplies Acid Red 388 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 | Red solid |
| Identification (IR) | Conforms to Reference |
| UV/VIS | 0.436% |
Storage & handling
| Property | Value |
|---|---|
| Storage Temperature | Ambient |
| Acidity | Base |
Literature values
Published physical properties of the substance, not batch specifications.
| Property | Value |
|---|---|
| Appearance | Dark powder |
| pKa | pKa = 5.1 |
| log P (octanol/water) | -1.33 |
Source: PubChem CID 37718 (HSDB)
Identification
| Property | Value |
|---|---|
| SKU | 42776804 |
| CAS Number | 37299-86-8 |
| IUPAC Name | disodium;4-[3-(diethylamino)-6-diethylazaniumylidenexanthen-9-yl]benzene-1,3-dicarboxylate;chloride |
| Molecular Formula | C29H29N2O5•Cl•Na2 |
| Molecular Weight | 566.98 |
| 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 |
| HTS Code | 3204125090 |
| Tariff Code | 3204120090 |
Safety & GHS
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Health Hazard
GHS07
Hazard statements
- H315 Causes skin irritation
- H319 Causes serious eye irritation
Precautionary statements
- P280 Wear protective gloves/protective clothing/eye protection/face protection
- P301+312 IF SWALLOWED: Call a POISON CENTER or doctor/physician if you feel unwell
- P302+352 IF ON SKIN: Wash with soap and water
- P305+351+338 IF IN EYES: Rinse with water for several minutes. Remove contact lenses if present and easy to do. Continue rinsing
Documents
Safety Data Sheets (SDS)
Available in English, French, German, Italian, 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
No alternate names recorded for this product.
Frequently asked questions
What is Acid Red 388 (Rhodamine WT) commonly used for?
Acid Red 388 (Rhodamine WT) is primarily used as a fluorescent water-tracing dye in hydrological and environmental studies, such as groundwater and surface-water flow tracing and dye-dilution studies.
What is the chemical formula and molecular weight of Acid Red 388?
The chemical formula is C₂₉H₂₉N₂O₅•Cl•Na₂ with a molecular weight of 566.98 g/mol.
How should Acid Red 388 be stored?
Store at ambient temperature in a tightly sealed container, away from moisture and direct sunlight.
What grade or purity is Acid Red 388 available in?
Molekula supplies Acid Red 388 in analytical and technical grades, with purity typically ≥95% unless specified otherwise.
Can Molekula supply Acid Red 388 in bulk quantities?
Yes, we offer bulk quantities of Acid Red 388 upon request, subject to availability and order minimums.
What documentation comes with an order of Acid Red 388?
Each order includes a Certificate of Analysis (CoA), Material Safety Data Sheet (MSDS), and a product specification sheet.
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.