Description

Phenolphthalein Disulfate Tripotassium Salt Trihydrate is a high-purity, water-soluble salt derivative of phenolphthalein, a classic acid-base indicator. This compound matters for its enhanced stability and solubility in aqueous systems compared to the free acid form, making it a critical reagent in advanced analytical and diagnostic applications. It is primarily needed by manufacturers and research laboratories in the pharmaceutical, biotechnology, and clinical diagnostics sectors for precise pH-dependent assays and enzymatic activity measurements.

Application

• Clinical Diagnostic Kits: Used as a chromogenic substrate in enzymatic assays for clinical chemistry analyzers to detect specific biomarkers.
• Biochemical Research: Serves as a sensitive probe for studying enzyme kinetics, particularly phosphatases and sulfatases, in life science research.
• Pharmaceutical Quality Control: Employed in analytical methods for drug purity testing and stability-indicating assays.
• Microplate-Based Assays (ELISA): Functions as a reporting dye in high-throughput screening and immunoassay platforms.
• Water Analysis: Can be utilized in specialized test kits for determining alkaline phosphatase activity as an indicator of water quality.
• Educational & Reference Standards: Provides a reliable and consistent standard for teaching laboratories and method calibration.

Basic Information

Product Name	Phenolphthalein Disulfate Tripotassium Salt Trihydrate
CAS No.	62625-16-5
Molecular Formula	C20H12K3O14S2 • 3H2O
Molecular Weight	728.84 g/mol (Anhydrous basis: 674.79 g/mol)
Synonyms	Phenolphthalein Diphosphate Tripotassium Salt (common misnomer); Phenolphthalein 3',3''-Bis(sulfate) Tripotassium Salt Trihydrate; Tripotassium Phenolphthalein Disulfate Trihydrate; Phenolphthalein Disulfonic Acid Tripotassium Salt; PSP Substrate; Phenolphthalein Sulfate Potassium Salt; Diagnostic Grade Phenolphthalein Derivative
EINECS	Contact for details

Quality Control

Our Phenolphthalein Disulfate Tripotassium Salt Trihydrate is manufactured under strict quality management systems. Each batch undergoes rigorous analytical testing to ensure it meets the high-purity standards required for diagnostic and research applications. A comprehensive Certificate of Analysis (COA) detailing purity, identity, and performance in application-specific tests is provided with every shipment.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at a controlled room temperature (15-25°C). Due to its hygroscopic (moisture-sensitive) nature, the container must be kept tightly sealed in a dry environment to prevent absorption of atmospheric moisture and subsequent degradation.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 98.0% (on anhydrous basis)
Water Content (KF)	6.5 - 8.5 % (Theoretical for Trihydrate: ~7.4%)
pH (1% Solution)	7.0 - 9.0
Solubility	Freely soluble in water; clear, colorless solution
Heavy Metals (as Pb)	≤ 10 ppm
Performance in Assay	Conforms to reference standard activity

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