Comparing E102 - Tartrazine vs E124 - Ponceau 4r
Overview
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Found in 23,316 products
Found in 14 products
Search rank & volume
Awareness score
Search volume over time
Interest over time for 12 keywords in U.S. during the last 10 years.
Interest over time for 6 keywords in U.S. during the last 10 years.
Popular questions
Is yellow 5 bad for you?
At permitted food-use levels, tartrazine (FD&C Yellow 5) is considered safe by regulators (ADI up to 7.5 mg/kg body weight/day). A small number of people—especially those with aspirin sensitivity—may have hives or asthma-like reactions, and the EU requires a label about possible effects on activity and attention in children.
What is yellow 5 made of?
It is a synthetic azo dye: the trisodium salt of a sulfonated aromatic azo compound based on a pyrazolone ring (C.I. 19140). It is produced from petroleum-derived intermediates such as sulfonated anilines and a pyrazolone derivative.
Is yellow 5 bad?
For most consumers, no—it's approved and considered safe at typical dietary intakes. Rare hypersensitivity reactions can occur, and some children may be susceptible to small, reversible effects on behavior.
What does yellow 5 do to your body?
It primarily provides color and is largely excreted, with a small portion metabolized by gut bacteria before elimination. In sensitive individuals it can trigger hives or wheezing, and some children may experience mild, short-lived effects on activity or attention.
How is yellow 5 made?
Industrially, sulfanilic acid (or similar sulfonated anilines) is diazotized and azo-coupled to a pyrazolone derivative, then neutralized to form the trisodium salt. Lake forms are made by precipitating the dye onto an insoluble substrate such as aluminum hydroxide.
How does ponceau stain work?
In labs, “Ponceau stain” usually means Ponceau S (not the food color E124 Ponceau 4R); it’s an anionic azo dye that reversibly binds proteins on nitrocellulose or PVDF via electrostatic and hydrophobic interactions, giving red bands. As a similar sulfonated azo dye, E124 would color proteins non‑specifically by the same principle but isn’t the standard reagent.
How to image ponceau stained membrane?
Rinse to lower background, then image the wet membrane under white light with a flatbed scanner, gel imager, or phone camera—no special filters needed. After imaging, destain with water or TBST before immunodetection.
How to make ponceau s solution?
Ponceau S (different from E124) is typically prepared as 0.1% w/v dye in 5% v/v acetic acid in water; mix to dissolve and filter. Store at room temperature; optionally include ~0.1% SDS to speed staining.
How to make ponceau stain?
For protein blots, use Ponceau S: 0.1% w/v in 5% v/v acetic acid (water), filter, and use to briefly stain the membrane. E124 Ponceau 4R is a food colorant and isn’t standard for this application.
How to remove ponceau stain?
Wash the membrane in water or TBST until the red color disappears (typically 1–5 minutes); the staining is fully reversible and compatible with later antibody probing. If background persists, a brief rinse in dilute base (e.g., ~0.1 M NaOH) can clear it quickly.