Description

Naphthol As-E Phosphate CAS NO 18228-17-6 is a specialized phosphate ester derivative of a naphthol AS dye intermediate, serving as a key chromogenic substrate in biochemical assays. This compound is valued for its ability to produce a distinct, measurable color change upon enzymatic cleavage, making it indispensable for precise detection and quantification. It is primarily required by manufacturers and research laboratories in the diagnostics, biotechnology, and life sciences sectors for developing enzyme-linked immunosorbent assays (ELISA) and other histochemical staining kits.

Application

• Primary substrate for alkaline phosphatase (ALP) in ELISA and Western blot detection systems.
• Chromogenic agent for histochemical and cytochemical staining in pathology and research microscopy.
• Key component in the formulation of diagnostic kits for clinical and veterinary testing.
• Used in biochemical research for studying enzyme kinetics and inhibition.
• Raw material for synthesizing more complex dye intermediates and specialized reagents.
• Potential use in the development of biosensors and other analytical devices.

Basic Information

Product Name	Naphthol As-E Phosphate
CAS No.	18228-17-6
Molecular Formula	C19H16NO6P
Molecular Weight	385.31 g/mol
Synonyms	Naphthol AS-E Phosphate; 3-Hydroxy-2-naphthoic acid 2,4-dimethylanilide phosphate; 3-Hydroxy-N-(2,4-dimethylphenyl)-2-naphthamide phosphate; Naphthol AS-E phosphate salt; Fast Red TR phosphate; AS-E Phosphate; Phosphoric acid mono-[3-[(2,4-dimethyl-phenylcarbamoyl)-2-hydroxy-naphthalen-1-yl] ester]; Azoic Coupling Component 4 (phosphate derivative)
EINECS	Contact for details

Quality Control

Our Naphthol As-E Phosphate is manufactured under strict quality management systems to ensure batch-to-batch consistency and high performance in sensitive applications. Each lot is tested to confirm identity, purity, and suitability as a chromogenic substrate. A comprehensive Certificate of Analysis (COA) detailing purity (typically >95% by HPLC), absorbance characteristics, and functional performance is provided with every shipment to support your quality assurance protocols.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at a controlled room temperature (15-25°C). This product is hygroscopic (moisture-sensitive); ensure the container is sealed after each use to prevent degradation from atmospheric humidity. Keep away from strong oxidizing agents.

Specification

Item	Specification
Appearance	Off-white to light tan powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 95.0%
Solubility	Soluble in DMF, DMSO; slightly soluble in water
Loss on Drying	≤ 2.0%
Heavy Metals	≤ 20 ppm
Functional Test (Enzymatic)	Conforms (Clear color development with ALP)

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.