For procurement professionals and R&D scientists in the chemical and pharmaceutical industries, sourcing high-quality reagents is a critical task. Cresol Purple (CAS 2303-01-7) is one such vital compound, primarily utilized as a pH indicator. This guide aims to assist buyers in understanding the key aspects of this chemical and how to effectively source it.

Cresol Purple, also known as m-Cresol Purple or metacresol purple, is a sulfonphthalein dye. Its chemical formula is C21H18O5S, and it typically presents as a purple to dark purple crystalline powder. The chemical's primary function is as an acid-base indicator, exhibiting distinct color changes at different pH levels. It transitions from red to yellow in the acidic range (pH 1.2-2.8) and from yellow to purple in the alkaline range (pH 7.6-9.2). This characteristic makes it invaluable for detecting the alkalinity of water and for use in various analytical tests.

When considering a purchase, buyers typically look for specific technical parameters. These include a purity level of ≥98%, a low residue on ignition (≤0.2%), and minimal loss on drying (≤0.5%). For research scientists and product formulators, these specifications are crucial for ensuring the accuracy and reliability of their experiments and final products. The consistency in appearance, from purple to dark purple crystalline powder, is also a common quality indicator.

As a buyer, understanding where to purchase Cresol Purple is essential. Identifying a reputable manufacturer and supplier, especially one based in China, can offer significant advantages in terms of price and supply chain stability. When you are looking to buy Cresol Purple, consider manufacturers who provide comprehensive product documentation, such as Certificates of Analysis (CoA) and Safety Data Sheets (SDS).

For businesses needing regular or bulk supplies, establishing a relationship with a dependable chemical supplier is key. Factors such as efficient packaging (e.g., 25KG drums), timely delivery, and responsive customer support are important considerations. If you are in the market to purchase Cresol Purple and are seeking a trusted supplier that offers both quality and competitive pricing, engaging directly with established chemical manufacturers is the recommended approach.