Sunset Yellow Aluminum Lake BP EP USP Pharma Grade: Description and Properties

What is Sunset Yellow Aluminum Lake BP EP USP Pharma Grade?

Sunset Yellow Aluminum Lake BP EP USP Pharma Grade stands among the essential synthetic colorants used in pharmaceuticals, foods, and cosmetics. This pigment does not appear in nature. Chemically, it comes from Sunset Yellow FCF (FD&C Yellow 6), but in lake form, it fuses with aluminum hydroxide, creating a shade-insoluble, stable material. It has an assigned E number, E110, and carries a European Pharmacopoeia (EP), British Pharmacopoeia (BP), and United States Pharmacopeia (USP) grade badge, which signals a defined high standard for purity, traceability, and safety required in pharmaceutical manufacture.

Molecular Structure, Formula, and HS Code

This lake pigment’s backbone comes from aromatic sulfonated azo compounds. The molecular formula reads as C16H10N2Na2O7S2, for the base dye. The lake complex broadly summarizes as C16H10N2Na2O7S2·xAl(OH)3, where aluminum hydroxide molecules embed the Sunset Yellow FCF. Its molecular weight hovers around 492 grams per mole for the un-laked form, and density often falls close to 1.7 g/cm³. The international trade code, HS Code 32030090, covers synthetic organic coloring matter and preparations used in pharmaceutical coloring and coating. This identifier anchors its legality through supply chains across global markets.

Physical Characteristics

Sunset Yellow Aluminum Lake appears in several forms, depending on purpose. Flakes, solid blocks, fine powders, or granules—each format shows a vibrant yellow-to-orange shade, a hallmark of the coloring system. Powders present as soft, free-flowing, while pearls offer a higher degree of smoothness and luster under light. Unlike the base dye, the lake settles in water and resists dissolution, which locks the color inside tablets or capsules. In solution with certain acids or alkalis, the color shows stability, but strong oxidizing agents break it down.

Properties and Handling

This lake pigment resists fading under standard processing heat and light. It adheres well to surfaces and maintains color through shelf life. It does not dissolve in oil or water but disperses thoroughly, giving a consistent hue inside dosage forms. Density runs close to 1.6 to 1.7 g/cm³, which fits automated manufacturing protocols in coating pans and mixers. Particulate size often sits below 12 microns for pharmaceutical grade, encouraging uniform color distribution. Storage in sealed containers at cool, dry room temperature keeps the pigment stable for years. Once moisture hits, clumping or cake formation can present a handling problem.

Safety and Regulatory Considerations

This pigment has built-in controls to limit known hazards or harmful effects. The allowable limits for heavy metals, such as lead, arsenic, and mercury, fall under strict scrutiny. Exposure, mostly by ingestion in foods or medication, gets governed by rules set by global authorities, including the EMA, US FDA, and Indian CDSCO. The finished pigment shows little to no dust hazard in normal handling, and allergic responses in the population stay rare but remain possible. Sensitive groups, such as children, require reduced tolerances for synthetic additives. Clearing the raw materials of possible carcinogens and confirming the absence of solvents, unreacted intermediates, or microbial contamination stays core to pharma auditing standards. Approved lots get supported by full certificates of analysis and traceability documentation.

Manufacturing and Raw Material Sources

Creating this lake coloring begins with high-purity Sunset Yellow FCF dye. Reaction with aluminum hydroxide in a controlled, pH-adjusted slurry yields small pigment particles. Filtration, repeated washing, and controlled drying produce the endpoint powder, flake, or pearl form. Surface area, porosity, and residual moisture need constant analytical checking. Each batch gets monitored for inorganic residue, dye content, and the absence of foreign matter—a quality essential in oral dosage forms. Sourcing places high demand on sustainable, audited origin of base dye and mineral reagents, as a pharma-grade lot cannot accept contaminants from recycled or industrial-grade materials.

Applications and Considerations for Manufacturers

Pharmaceutical tablet and capsule coatings rank as the core use for this lake pigment. Its color keeps products recognizable and supports accurate patient dosing, reducing the chances of mix-ups. Formulators pick lakes for their color-embedding feature, which resists leaching and migration. Liquid, crystal, and solution forms see use in liquid dose or topical formulations where a bright, stable yellow-orange color signals product type and flavor. This pigment also plays a role in food and beverages; though dose limits restrict use in regions with tighter allergen or toxicity requirements. Cosmetic manufacturers choose this lake for lipsticks, powders, and creams where a consistent pigment body enhances brand repeatability.

Challenges and Industry Solutions

Concerns over synthetic food dyes have sharpened in recent years. Parents, schools, and advocacy groups lobby for tighter control following periodic reports tying azo dyes to hyperactivity or allergic reactions. The European Union enforces warning labels on foods using this colorant, and some manufacturers now pivot toward natural alternatives. Still, for many applications, especially in pharma, synthetic lakes offer unmatched stability and cost effectiveness. One solution lies in doubling down on transparency, rigorous batch tracking, and independent lab testing. Exploring biotechnology routes for pigment synthesis could offset some concerns, but at a higher production cost for now. The industry keeps scanning for new non-toxic, renewable sources of color, but it takes robust safety data and years of stability testing to challenge the legacy of synthetic lakes in regulated markets.

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