Description

o-Cresolphthalein Complexone is a high-purity, synthetic organic compound widely recognized as a highly sensitive metallochromic indicator. Its primary value lies in its exceptional ability to form stable, colored complexes with calcium and other divalent metal ions, enabling precise endpoint detection in complexometric titrations. This reagent is essential for analytical chemists and quality control laboratories in industries such as pharmaceuticals, water treatment, and clinical diagnostics, where accurate quantification of calcium and magnesium is critical.

Application

• Complexometric Titration Indicator: The primary application is as a visual indicator for the titration of calcium and magnesium ions with EDTA, particularly in water hardness testing.
• Clinical Chemistry Reagent: Used as a key component in diagnostic kits and automated analyzers for the colorimetric determination of serum calcium levels.
• Pharmaceutical Analysis: Employed in the quality control of raw materials and finished products where calcium content must be precisely assayed.
• Food & Beverage Testing: Applied in the analysis of calcium fortification in dairy products, infant formula, and beverages.
• Environmental Monitoring: Utilized for determining water hardness in industrial wastewater, boiler feed water, and natural water sources.
• Research & Development: Serves as a selective chelating agent in biochemical and metallurgical research for studying metal ion interactions.

Basic Information

Product Name	o-Cresolphthalein Complexone
CAS No.	2411-89-4
Molecular Formula	C32H32N2O12
Molecular Weight	636.61 g/mol
Synonyms	o-Cresolphthalein Complexon; Phthalein Purple; 3',3''-Bis[N,N-bis(carboxymethyl)aminomethyl]-o-cresolphthalein; CPC; o-CPC; NSC 82167; o-Cresolphthalein-3',3''-bis(methyliminodiacetic acid); Calcium Colorimetric Indicator
EINECS	219-319-5

Quality Control

Our o-Cresolphthalein Complexone is manufactured under a strict quality management system. Each batch undergoes comprehensive analytical testing, including identity confirmation by IR spectroscopy, purity assessment by HPLC, and performance validation in standard titration methods. We provide full traceability and Certificates of Analysis (COA) are available for every shipment, ensuring compliance with in-house specifications suitable for analytical and diagnostic applications.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at a controlled room temperature (15-25°C). The product is light-sensitive and should be handled accordingly to maintain stability and performance.

Specification

Item	Specification
Appearance	White to off-white powder
Identification (IR)	Conforms to reference spectrum
Assay (HPLC)	≥ 98.0%
Loss on Drying	≤ 1.0 %
Residue on Ignition	≤ 0.1 %
Absorbance Ratio (A580/A430)	≥ 2.5 (in Ca²⁺ complex)
Heavy Metals (as Pb)	≤ 20 ppm

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