3-IP sodium salt

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MedKoo CAT#: 464813

CAS#: 3318-43-2 (sodium)

Description: 3-Indoxyl phosphate (3-IP) is a chromogenic and electrochemical substrate for alkaline phosphatase. Upon enzymatic cleavage by alkaline phosphatase, 3-indoxyl is released and subsequently oxidized to produce water-insoluble indigo, which can be quantified by colorimetric detection at 660 nm as a measure of alkaline phosphatase activity. 3-Indoxyl phosphate can also be converted to water-soluble leucoindigo by reduction of indigo in alkaline solution by sodium dithionite, which can be quantified by colorimetric detection at 415 nm or voltametric detection as a measure of alkaline phosphatase activity. 3-Indoxyl phosphate has been used in ELISAs.

Chemical Structure

3-IP sodium salt
CAS# 3318-43-2 (sodium)

Theoretical Analysis

MedKoo Cat#: 464813
Name: 3-IP sodium salt
CAS#: 3318-43-2 (sodium)
Chemical Formula: C8H6NNa2O4P
Exact Mass:
Molecular Weight: 257.0923
Elemental Analysis: C, 37.37; H, 2.35; N, 5.45; Na, 17.88; O, 24.89; P, 12.05

Price and Availability

Size Price Availability Quantity
250.0mg USD 350.0 2 Weeks
1.0g USD 950.0 2 Weeks
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Synonym: 3-IP sodium salt; 3IP sodium salt; 3 IP sodium salt; 3-Indoxyl Phosphate sodium salt; 3 Indoxyl Phosphate sodium salt; 3Indoxyl Phosphate sodium salt;

IUPAC/Chemical Name: sodium 1H-indol-3-yl phosphate


InChi Code: InChI=1S/C8H8NO4P.2Na/c10-14(11,12)13-8-5-9-7-4-2-1-3-6(7)8;;/h1-5,9H,(H2,10,11,12);;/q;2*+1/p-2

SMILES Code: O=P(OC1=CNC2=C1C=CC=C2)([O-])[O-].[Na+].[Na+]

Appearance: Solid powder

Purity: >98% (or refer to the Certificate of Analysis)

Shipping Condition: Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition: Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).

Solubility: To be determined

Shelf Life: >2 years if stored properly

Drug Formulation: To be determined

Stock Solution Storage: 0 - 4 C for short term (days to weeks), or -20 C for long term (months).

HS Tariff Code: 2934.99.9001

Solubility Data

Solvent Max Conc. mg/mL Max Conc. mM
PBS (pH 7.2) 10.0 38.9

Preparing Stock Solutions

The following data is based on the product molecular weight 257.0923 Batch specific molecular weights may vary from batch to batch due to the degree of hydration, which will affect the solvent volumes required to prepare stock solutions.

Recalculate based on batch purity %
Concentration / Solvent Volume / Mass 1 mg 5 mg 10 mg
1 mM 1.15 mL 5.76 mL 11.51 mL
5 mM 0.23 mL 1.15 mL 2.3 mL
10 mM 0.12 mL 0.58 mL 1.15 mL
50 mM 0.02 mL 0.12 mL 0.23 mL

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