Indoxyl phosphate disodium salt
Indoxyl phosphate disodium salt (CAS 3318-43-2, C8H6NNa2O4P) is a water-soluble organic compound with a molecular weight of 257.09 g/mol. It functions as a chromogenic substrate for alkaline phosphatase. Upon enzymatic hydrolysis, it releases indoxyl, which dimerises and oxidises to form a blue indigo dye. This characteristic makes it valuable in biochemical assays and diagnostic kits for detecting alkaline phosphatase activity in various biological samples.
- IUPAC
- 3-Indoxyl phosphate disodium salt,Disodium 3-indoxyl phosphate

Enzyme Substrate
Indoxyl phosphate disodium salt is widely used as a chromogenic substrate for the enzyme alkaline phosphatase. Its hydrolysis by alkaline phosphatase yields a detectable blue precipitate (indigo dye), enabling quantitative and qualitative assays.
Biochemical Research
This compound is a key reagent in biochemical research, particularly in studies involving enzyme kinetics and analysis of alkaline phosphatase activity in cellular and tissue samples.
Diagnostic Kits
Utilised in the development and manufacturing of diagnostic kits for detecting alkaline phosphatase levels, which can be indicative of various physiological or pathological conditions.
| Molecular weight | 257.09 |
|---|---|
| Empirical formula | C8H6NNa2O4P |
| Storage temperature | −20°C |
| Protective equipment | Eyeshields, Gloves, type N95 (US), type P1 (EN143) respirator filter |
|---|---|
| Water hazard class (WGK, DE) | 3 |
Hazard information is provided for guidance. Always consult the product Safety Data Sheet (SDS), available on request, before handling.
Documentation
Every batch ships with a Certificate of Analysis covering assay, identity and purity; the grade is confirmed against your enquiry. Safety Data Sheets and technical data sheets are available on request.
Supply & logistics
Samples for technical evaluation; bulk MOQ by grade and packaging. In-stock material ships in 7–10 working days, worldwide, with full export documentation.
What is Indoxyl phosphate disodium salt used for?
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Indoxyl phosphate disodium salt is primarily used as a chromogenic substrate for alkaline phosphatase in biochemical assays, research, and diagnostic kits.
What is the CAS number and formula for Indoxyl phosphate disodium salt?
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The CAS number is 3318-43-2, and the empirical formula is C8H6NNa2O4P.
What grade and purity does Tech Serve Solutions supply?
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Tech Serve Solutions supplies Indoxyl phosphate disodium salt for research purposes. We do not represent it as USP, BP, or EP grade. Please refer to the product specification sheet for available purities.
How should Indoxyl phosphate disodium salt be handled and stored?
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Handle with appropriate personal protective equipment, including eyeshields and gloves. A respirator filter such as type N95 (US) or type P1 (EN143) is recommended. Store at -20°C. This compound is classified under WGK Germany 3, indicating a high hazard to water.
Is Indoxyl phosphate disodium salt a controlled substance?
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The provided data does not indicate that Indoxyl phosphate disodium salt is a controlled substance.
How can I request a quote or sample?
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To request a quote or sample, please contact our sales team through the website or by phone, providing the product name and CAS number (3318-43-2).
How is Indoxyl phosphate disodium salt packed and exported?
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Tech Serve Solutions packs and exports Indoxyl phosphate disodium salt adhering to all necessary safety and shipping regulations for chemical compounds. Contact us for specific export documentation and details.
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