In the world of analytical chemistry and biological sciences, the accurate determination of pH is often a critical step. pH indicators are chemical substances that change color in response to changes in pH, offering a simple visual method for pH measurement. Among the myriad of indicators available, Phenol Red, identified by CAS number 143-74-8, stands out for its widespread use and specific properties. However, choosing the right indicator for a particular application requires understanding its characteristics and how they compare to other options. If you are considering Phenol Red, or need a reliable supplier, NINGBO INNO PHARMCHEM CO.,LTD., a distinguished manufacturer in China, can provide you with high-quality products.

Phenol Red is a sulfonphthalein dye that exhibits a color change from yellow (at pH < 6.6) to red (at pH > 8.0). This transition occurs in the slightly acidic to alkaline range, making it particularly useful for titrations involving weak acids and strong bases, or for monitoring processes that occur around neutral pH. Its solid form and solubility in alkaline solutions are convenient for laboratory preparation. When you buy Phenol Red, you are choosing an indicator that is also commonly used in cell culture media due to its visual cue for monitoring cell health and metabolic activity.

When comparing Phenol Red to other common pH indicators, its specific transition range is its defining feature. For instance, indicators like Bromothymol Blue change color in a similar range (pH 6.0-7.6), but Phenol Red offers a more distinct yellow-to-red shift that can be easier to discern in certain conditions. Litmus, another classic indicator, provides a less precise red/blue color change over a broader pH range. Methyl Orange, on the other hand, is suitable for stronger acidic ranges (pH 3.1-4.4). The choice often depends on the specific pH value you need to detect. If your application requires monitoring around pH 7, Phenol Red is often an excellent choice.

While Phenol Red is highly versatile, it's important to be aware of potential limitations. For highly precise measurements, especially in research requiring exceptional accuracy or in situations where the indicator itself might interfere with the reaction, instrumental methods like using a pH meter are preferred. Additionally, some cell lines can be sensitive to Phenol Red in culture media, necessitating the use of Phenol Red-free formulations for specific experiments. Nonetheless, for general laboratory work, educational purposes, and routine cell culture monitoring, Phenol Red remains a valuable and economical choice. NINGBO INNO PHARMCHEM CO.,LTD. is committed to supplying laboratories with reliable Phenol Red (CAS 143-74-8) and other essential chemicals. We encourage you to consult with our experts to determine the best indicator for your specific application.