Description

Bromocresol Purple is a high-purity, triphenylmethane-based pH indicator dye, widely recognized for its distinct color transition in analytical chemistry. Its primary value lies in providing a clear, reliable visual endpoint for precise pH determination and titration analysis across various scientific and industrial processes. This compound is essential for professionals in pharmaceutical quality control, microbiological media preparation, and research laboratories requiring accurate acid-base measurements. Its consistent performance makes it a critical reagent for ensuring analytical integrity and process validation.

Application

• pH Indicator in Titrations: Used as a visual endpoint indicator in acid-base titrations, particularly effective in the pH range of 5.2 (yellow) to 6.8 (purple).
• Microbiological Media: Incorporated into culture media as a pH indicator to monitor microbial growth and metabolic activity, such as in carbohydrate fermentation tests.
• Clinical & Diagnostic Reagents: A key component in diagnostic kits and reagents for clinical chemistry analyses, including serum albumin determination.
• Biochemical Research: Employed in electrophoresis and chromatography as a tracking dye, and in various buffer systems to monitor pH changes.
• Industrial Process Control: Utilized in chemical manufacturing and water treatment facilities to monitor reaction pH and ensure process consistency.
• Educational Laboratories: Serves as a standard pH indicator in academic settings for teaching fundamental principles of analytical chemistry.

Basic Information

Product Name	Bromocresol Purple
CAS No.	115-40-2
Molecular Formula	C21H16Br2O5S
Molecular Weight	540.22 g/mol
Synonyms	3',3''-Dibromophenolsulfonephthalein; 5,5'-Dibromo-o-cresolsulfonephthalein; Bromcresol Purple; BCP; Dibromocresolsulfonephthalein; NSC 6111; 4,4'-(3H-2,1-Benzoxathiol-3-ylidene)bis(2,6-dibromophenol) S,S-dioxide
EINECS	204-087-8

Quality Control

Our Bromocresol Purple is manufactured under a strict quality management system to ensure batch-to-batch consistency and reliability. Each lot is subjected to comprehensive analytical testing, including identification by infrared spectroscopy (IR), purity assay by high-performance liquid chromatography (HPLC), and verification of key physical properties. A Certificate of Analysis (COA) detailing all test results is provided with every shipment to support your quality assurance and regulatory compliance needs.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, well-ventilated area at a controlled room temperature (15-25°C). Keep away from heat, sparks, and open flame. The product is light-sensitive and should be stored away from direct light exposure to maintain stability.

Specification

Item	Specification
Appearance	Light tan to pinkish-tan powder
Identification (IR)	Conforms to reference spectrum
Assay (HPLC)	≥ 95.0%
pH Transition Range	5.2 (yellow) to 6.8 (purple)
Loss on Drying	≤ 2.0 %
Residue on Ignition	≤ 0.5 %
Solubility	Soluble in ethanol, alkali; slightly soluble in water

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