|
HS Code |
428118 |
| Productname | Phenol Red (Reagent) |
| Casnumber | 143-74-8 |
| Molecularformula | C19H14O5S |
| Molecularweight | 354.38 g/mol |
| Appearance | Red to purple powder |
| Solubility | Soluble in water and ethanol |
| Phindicatorrange | 6.8 to 8.4 |
| Colorchange | Yellow (pH < 6.8), Red (pH 7.4-8.2), Fuchsia (pH > 8.4) |
| Storagetemperature | 2-8°C |
| Purity | ≥98% |
| Meltingpoint | 285-288°C (decomposes) |
| Synonyms | Phenolsulfonphthalein, PSP |
| Usage | pH indicator in cell culture and clinical diagnostics |
As an accredited Phenol Red(Reagent) factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Phenol Red (Reagent), 100g, is packaged in a sealed, amber HDPE bottle with tamper-evident cap and clear labeling. |
| Shipping | Phenol Red (Reagent) is shipped in tightly sealed containers to prevent contamination and degradation. It is typically transported at controlled room temperature and protected from light and moisture. The package includes appropriate labels indicating it is a laboratory chemical, and all shipments comply with relevant safety and regulatory guidelines for chemical transport. |
| Storage | Phenol Red (Reagent) should be stored in a tightly closed container in a cool, dry, and well-ventilated area, away from incompatible materials such as strong oxidizers. Protect it from light and moisture. Store at room temperature, generally between 15°C and 30°C (59°F–86°F). Proper labeling and adherence to safety guidelines are essential to prevent contamination and ensure safe handling. |
Competitive Phenol Red(Reagent) prices that fit your budget—flexible terms and customized quotes for every order.
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Every chemist and biologist recognizes Phenol Red as an essential part of everyday laboratory work. As one of the leading manufacturers of Phenol Red (Reagent), we have followed its evolution and proven applications in biochemistry, environmental analysis, and clinical diagnostics. Because we have managed both formulation and large-scale production, we see up close how subtle differences in composition and purity can translate into measurable improvements in laboratory outcomes.
Our Phenol Red (Reagent) typically comes in a sodium salt form, the preferred version for aqueous media preparation. This formulation supports better solubility and enhanced stability, enabling repeatability across many test systems. We produce the product under the commonly recognized model name Phenol Red Reagent, GR Grade. The GR designation points to General Reagent grade, confirming a consistent minimum assay above 99%. Few issues disrupt workflow more than inconsistent indicator response, so we monitor for trace impurities that can color results or shift the pH transition zone.
Being hands-on in every step, we control parameters such as particle size and moisture content to prevent clumping in containers or uneven dissolution in solutions. Batch homogeneity is regularly verified, and we conduct spectrophotometric analysis to check for spectral purity; this step matters for researchers using Phenol Red in photometric pH readings.
In our conversations with lab directors and technicians, we hear repeatedly that they rely on Phenol Red primarily for its sharp pH transition range—approximately from pH 6.8 (yellow) to pH 8.2 (red). This property makes it the indicator of choice in cell culture work. Cell cultures, including both bacterial and mammalian cells, flourish best within narrow pH windows. Phenol Red provides an at-a-glance gauge for culture medium acidification due to metabolic activity. If left unchecked, acidification can lead to cell death and wasted resources.
Beyond cell culture, water treatment facilities depend on colorimetric pH readings during potable water analysis. Even small mistakes at this stage can lead to community health hazards or regulatory penalties, so the indicator’s reliability underpins their trust in the process. We keep tight controls on lot-to-lot color point accuracy because technicians notice any shift in color transition, especially in side-by-side trials comparing water quality samples.
Clinical diagnostic teams have similar demands on Phenol Red for urine tests, kidney function investigations, and various biochemical assays. Its repeatable color change plays a role in semi-quantitative measurements essential in hospital laboratories. A misreading can cause delays or even diagnostic mistakes, so manufacturers like us must deliver precisely formulated and tested batches.
From our years of in-house testing, we’ve developed a clear sense of how Phenol Red (Reagent) stands apart from other indicators including Bromothymol Blue, Methyl Red, or Cresol Red. The main technical distinction lies in its intermediate transition range. For microbiologists maintaining cell lines, an indicator like Bromothymol Blue doesn’t provide the same clarity in the crucial pH window supporting mammalian cells. Methyl Red, with its transition point around pH 4.4-6.2, is better suited to titrations in acidic solutions, not biological pH zones.
Phenol Red resists photodegradation better than many alternatives. Because our customers often keep their stocks for weeks or longer in well-lit environments, the inherent stability of our product means fewer wasted reagents and less time calibrating pH shifts after storage. Once exposed to air and light, some competitors’ batches of cresol-based dyes degrade noticeably faster – a cost in both time and materials.
Another point of difference involves ionic strength tolerance. Our Phenol Red Reagent formulation keeps color transitions consistent even when dissolved in various commonly used buffers, including saline and phosphate-based solutions. During product development, our team tested the dye in both low and high ionic strength samples relevant for hospital and analytical chemistry environments. The color shift retained its integrity, a reflection of our raw material sourcing and purification process.
You learn a lot about a product’s limitations and strengths when operating at scale. In producing Phenol Red, we spend as much time on source material qualification as on batch synthesis. Dye intermediates sourced from inconsistent supply channels sometimes introduce weak spots in color intensity or unusual absorption peaks under light. Years ago, we experienced a string of customer complaints linked directly to one change in raw material supplier. Today, we operate independent verification and keep close partnerships with trusted sources, paying above-market prices when necessary to secure proven raw inputs.
Our typical batch sizes range from several kilograms for specialty lots to drum-sized productions for major institutional clients. Small lot users—often universities or private research labs—benefit from the same quality assurance protocols as buyers with contract quantities. Each drum or vial that leaves our facility carries a unique lot record traceable to all major analytical checkpoints, from initial material intake through pH transition testing and spectrophotometric scans.
Spillage, cross-contamination, and airborne dust in production rooms represent genuine hazards. It pays to invest in dust collection and positive pressure environments. Even minimal traces of residual acid or base in vessels from upstream cleaning cycles can shift dye behavior, so our team built extensive rinsing and qualification steps between every tank transfer. Our operators undergo regular refresher training as minor deviations in handling sometimes result in noticeable color irregularities.
We don’t just manufacture and ship. Much of our insight comes from users reporting back with both positive and negative experiences. One university cell biology lab once informed us that switching to our Phenol Red from a leading European alternative resolved persistent streaking and uneven coloration in culture plates. That feedback led to tighter particle size control, confirmed by shipping test lots to partner labs for side-by-side medium preparation.
A water quality manager from a large metropolitan supply network pointed out that a rare batch once showed a delayed color transition close to the pH 7.0 endpoint. Following a full investigation using retained samples, our team traced this to a slight uptick in residual organic impurities, which slipped through an aging filtration cartridge. We redesigned quality checklists and improved our filtration protocol as a direct response. End user reviews often yield changes not captured by generic product specifications.
Purity forms the backbone of reliability. By manufacturing Phenol Red in controlled, sealed environments and maintaining rigorous standards throughout, we support laboratories where trust in every material is non-negotiable. Impurities like unreacted intermediates or byproducts diminish not just color intensity but can interfere in sensitive cell culture experiments, sometimes slowing cell growth or skewing analytical outcomes.
We regularly receive requests from researchers working on new cell lines or diagnostics platforms that demand purity levels above 99.5%. To meet this, we expanded our purification infrastructure, including dual-stage crystallization and analytical checks through HPLC. These investments have led to fewer non-conforming results and repeat orders, not just from clinical researchers but from environmental chemists seeking consistent performance in new regulatory test methods.
No two lots of biological materials behave the same, so as manufacturers, continuous vigilance keeps our technology at pace with applications in genetic diagnostics, drug discovery, and environmental monitoring where cell lines or chemical matrices shift. Purity and reliability sit at the intersection of production technology and user trust—without both, neither batch records nor projections serve the community’s progress.
As a manufacturer, you notice shipping and storage issues long before distributors report problems. Phenol Red suffers under high heat and humid conditions, leading to slower color changes or visible caking inside bottles. During summer months or long-distance transport, temperature controls become critical. After a particularly hot summer a decade ago, we introduced double-layered barrier packaging for export lots, after seeing clumping in samples pulled from seaport arrivals.
We urge all users to store unopened containers in a cool, dry place—ideally below 25°C. Once opened, exposure to atmospheric moisture can impact shelf life. Our packaging includes silica gel desiccants and moisture-tight lids. In-house, we track experimental shelf life both under ideal storage conditions and in deliberate “real-world” stress tests, exposing samples to laboratory bench light and variable humidity. These efforts let us confidently guarantee shelf life under typical working conditions.
Glass bottles and HDPE containers both have their place; glass offers better moisture resistance, but in busy labs, breakage becomes a hazard. By listening to both hospital pharmacists and water utility chemists, we now supply both container options, letting each client choose according to their usage environment.
Environmental responsibility means more than just regulatory paperwork. While Phenol Red holds minimal direct toxicity in diluted laboratory use, concentrated forms and large-scale spills deserve attention. We have seen old practices where labs flushed residues down standard drains, potentially impacting local water bacteria and aquatic organisms. Through collaboration with municipal waste handlers, we updated our labels and provided disposal instructions aligned to the newest EU and US standards for laboratory dyes.
Over time, we improved internal handling practices for phenolic intermediates to reduce both operator risk and potential byproducts. Off-gas scrubbers and on-site waste neutralization units keep emissions below industry limits. Audits from internal environmental stewards and regulatory inspectors keep us honest and up to date. We recommend that users combine spent solutions with excess sodium hypochlorite for neutralization under controlled conditions before disposal.
On the packaging front, we shifted to recyclable plastics and returnable drum programs for our largest users, reducing landfill contributions and fostering circular use. By treating environmental stewardship not as an afterthought, but as a key design principle, we encourage every downstream user to consider safe disposal and sustainability in their own operations.
Problems sometimes arise even with tightly controlled reagents. As the manufacturer, we find most issues stem from incorrect dissolution or unexpected interactions with components not listed in typical protocols. For example, researchers using ultrapure water with very low ionic strength noticed less vibrant color shifts. Adding a small amount of sodium chloride restored expected performance—something we now point out in product literature and support calls.
Another recurring issue involves filtration. Some users filter their Phenol Red solutions through fine-pore membranes, which sometimes adsorb dye and reduce final concentration—leading to pale yellow hues in cell media or false readings in test assays. We provide guidance on compatible filter types and recommend filter pre-conditioning with a weak dye solution to saturate binding sites.
Microbial contamination rarely affects our Phenol Red batches, but once in a while, customers using older media stocks encounter unexpected precipitation or turbidity. This is nearly always due to microbial introduction after opening. Our advice draws from our own experience: always make stock solutions fresh and discard those that sit open for long periods.
As producers, we maintain two-way communication with academe, clinical labs, and industry. Through regular customer workshops and joint studies, we adapt formulations when necessary and develop improved handling advice. Once, a consortium of food industry labs approached us unsure how to avoid particulate formation in high-protein sample matrices. By running joint testing protocols and reformulating stabilizing excipients, we produced a tailored variant they rely on to this day.
Sometimes, quality isn’t about formulation—it’s about knowledge transfer. Our technical team holds virtual seminars and responds directly to end-user questions. We encourage all laboratories to calibrate their procedures with small pilot batches of new dye shipments before integrating them into standardized workflow. This simple step, born from repeated troubleshooting, ensures that any lot-to-lot variation is detected early and does not impact critical experiments.
We also participate in round-robin quality trials run by reference laboratories, sending blind-coded samples to compare purity, color transition, and response curves with other top suppliers. These efforts drive us to further refine both product and process and highlight that continuous improvement is never just about cost—it's about leadership in reliable chemistry.
Phenol Red, though long established in chemistry and cell biology, evolves with every new application and research advance. We find that, with synthetic biology, precision diagnostics, and environmental analytics growth, the demands on indicator purity and consistency increase. In response, our plant constantly reviews process control systems, deepens raw material analysis, and explores greener synthetic pathways.
Hands-on involvement at every step—from raw material purchase to outgoing quality check—translates directly to scientific value in our clients' hands. The trajectory of Phenol Red in modern science depends on the synergy between reliable manufacturing and practical laboratory experience. We have learned that the more closely we listen to real scientists and technicians, the better we can continue to fine-tune and deliver a reagent that exceeds expectations, supports rigorous research, and stands up to decades of changing laboratory demands.
True manufacturing excellence in Phenol Red isn’t dictated by labels or theoretical grades, but by daily, tangible feedback from the field, consistent process controls, and honest commitment to user success.
