ASD-640
Tartrazine (E102) – Food Grade Yellow Colour Powder | CI 19140, CAS 1934-21-0 | ASD-640
$19.00
AUD ex GST
Biological Stains & Dyes · C.I. 19140
Tartrazine (E 102)
Water-soluble yellow azo dye for histological counterstaining, spectrophotometry, teaching and E 102 colour reference work.
Cat. No. ASD-640CAS 1934-21-0Dye content ≥ 85 %λmax ≈ 426 nmFood-grade E 102
Also known as: Acid Yellow 23, CI Food Yellow 4, Hydrazine Yellow. Sold in the US as FD&C Yellow No. 5 when FDA-certified.
At a Glance
FormulaC₁₆H₉N₄Na₃O₉S₂
Mol. weight534.36 g/mol
AppearanceOrange powder
1 % solutionLemon yellow
Solubility (water)Freely soluble
Batch dye content85.26 %
Overview
Tartrazine is the trisodium salt of a pyrazolone azo dye. Its two sulfonate groups and one carboxylate group make it highly water-soluble and anionic. The powder is orange, and dilute solutions are a clear lemon yellow with an absorption maximum near 426 nm.
In the laboratory, tartrazine is used as a yellow acid counterstain, a stable absorbance reference and a teaching dye. It is also the reference colour for E 102 work in food-colour analysis.
For laboratory, research, education and quality-control use. Not intended for human or veterinary therapeutic use, diagnosis, or direct consumption. Food-grade (E 102) material. For food-industry supply, contact Ausamics for suitability and regulatory documentation.
Colour at a Glance
Powder is orange to orange-red. Solution is lemon yellow. Colour intensity rises in direct proportion to concentration, which makes tartrazine a good Beer–Lambert teaching dye.
dilute solutionpowder
Key Applications
HistologyYellow counterstain, including Lendrum's phloxine–tartrazine method for viral inclusion bodies and Paneth cell granules.
Optical Clearing ResearchWater-soluble absorbing dye studied for making biological tissue optically transparent in imaging research.
SpectrophotometryStable yellow dye (λmax ≈ 426 nm) for Beer–Lambert calibration and absorbance teaching.
Food Colour QCReference material for E 102 identification, HPLC and colour-matching work.
EducationIntense, water-soluble colour for chromatography, colour-mixing and diffusion practicals.
Formulation DevelopmentYellow colourant for prototype buffers, gels and visual tracer solutions in research.
Advantages & Considerations
Advantages
- Pure dye content ≥ 85 % (current batch 85.26 %)
- Meets the E 102 purity limits on the batch certificate
- Very low heavy metals: lead and arsenic below 1 ppm
- Freely water-soluble; no heating needed
Considerations
- Not an FDA-certified FD&C Yellow No. 5 batch
- May cause skin sensitisation (H317); wear gloves
- Fades under strong oxidants and prolonged strong light
- Avoid creating dust when weighing
Specification Summary
| Parameter | Specification |
|---|---|
| Pure dye content (E 1 %, 1 cm at 426 nm) | Min. 85.0 % |
| Appearance | Orange to orange-red powder |
| Hue of 1 % solution | Lemon yellow |
| Loss on drying at 135 °C (as sodium salts) | Max. 15.0 % |
| Moisture at 110 °C | Max. 2.0 % |
| Water-insoluble matter | Max. 0.20 % |
| Subsidiary colouring matters | Max. 1.0 % |
| Organic compounds other than colouring matters | Max. 0.5 % |
| Unsulfonated primary aromatic amines (as aniline) | Max. 0.01 % |
| Ether-extractable matter | Max. 0.2 % |
| Arsenic (As) | Max. 1 ppm |
| Lead (Pb) | Max. 1 ppm |
| Mercury (Hg) | Max. 0.05 ppm |
| Cadmium (Cd) | Max. 0.1 ppm |
| Chromium (Cr) | Max. 2 ppm |
| Copper (Cu) | Max. 30 ppm |
| Zinc (Zn) | Max. 50 ppm |
| Heavy metals (as Pb) | Max. 5 ppm |
Frequently Asked Questions
Is tartrazine the same as E 102 and FD&C Yellow No. 5?
Tartrazine is the chemical name. E 102 is its European food-additive number, and FD&C Yellow No. 5 is the US name for FDA-certified batches. This product meets the E 102 purity limits on the batch certificate; it is not an FDA-certified FD&C batch.
How do I make a stock solution?
Dissolve 1.0 g in about 80 mL of purified water, stir until clear and make up to 100 mL to give a 1 % w/v solution. Tartrazine is freely soluble, so no heating is needed.
What wavelength should I use for absorbance measurements?
Tartrazine absorbs most strongly at about 426 nm in water. Use this wavelength for calibration curves and dye-content checks.
Does tartrazine need special storage?
Store at 15–25 °C in a dry place, tightly closed and away from sunlight. Shelf life is 36 months from manufacture under these conditions.
Can tartrazine cause sensitisation?
Tartrazine is classified by some suppliers as a skin sensitiser. Wear gloves and avoid breathing dust when weighing the powder.
Technical Specifications
| Catalogue No. | ASD-640 |
| C.I. number | 19140 |
| CAS / EC | 1934-21-0 / 217-699-5 |
| E number | E 102 |
| Formula | C₁₆H₉N₄Na₃O₉S₂ |
| Mol. weight | 534.36 g/mol |
| Dye content | Min. 85 % (E 1 %, 426 nm) |
| λmax | ≈ 426 nm (water) |
| Storage | 15–25 °C, dry, dark, tightly closed |
| Shelf life | 36 months from manufacture |
| Documents | TDS, SDS; batch COA on request |
Applications
- Phloxine–tartrazine counterstain
- Optical clearing research
- Spectrophotometry standard
- Chemistry and biology teaching
- E 102 reference and QC
Stock Solution (1 % w/v)
- Weigh 1.0 g of tartrazine.
- Add to about 80 mL of purified water.
- Stir until fully dissolved; no heating is needed.
- Make up to 100 mL with purified water.
- Store in a closed bottle at room temperature, away from light.
Storage & Stability
Store at 15–25 °C in a dry place, tightly closed and protected from sunlight, heat and moisture. Shelf life is 36 months from the date of manufacture under these conditions.
Technical Data Sheet — Tartrazine
TDS-ASD-640 · Rev 1.0 · November 20261. Identification
| Chemical name | Trisodium 5-oxo-1-(4-sulfonatophenyl)-4-[(4-sulfonatophenyl)hydrazono]-3-pyrazolecarboxylate |
| Synonyms | Tartrazine; Acid Yellow 23; CI Food Yellow 4; Hydrazine Yellow |
| C.I. number | 19140 |
| E number | E 102 |
| CAS number | 1934-21-0 |
| EC number | 217-699-5 |
| Molecular formula | C₁₆H₉N₄Na₃O₉S₂ |
| Molecular weight | 534.36 g/mol |
| Dye class | Pyrazolone monoazo, anionic (acid) dye |
2. Intended Use
Histological counterstain, spectrophotometric reference dye, teaching reagent and E 102 reference colour. For laboratory, research, education and quality-control use. Not intended for human or veterinary therapeutic use, diagnosis, or direct consumption.
3. Mode of Action
The sulfonate and carboxylate groups make tartrazine strongly anionic, so it binds positively charged tissue proteins in acidic stains. Its azo–pyrazolone chromophore absorbs blue light at about 426 nm, which gives the yellow colour.
4. Physical & Chemical Properties
| Appearance | Orange to orange-red powder |
| Colour of 1 % aqueous solution | Lemon yellow |
| Absorption maximum (λmax) | approx. 426 nm in water |
| Solubility | Freely soluble in water; slightly soluble in ethanol |
| Moisture at 110 °C | Max. 2.0 % |
| Light and heat | Good stability in normal laboratory conditions; protect from sunlight, heat and moisture |
5. Specifications
| Parameter | Specification |
|---|---|
| Pure dye content (E 1 %, 1 cm at 426 nm) | Min. 85.0 % |
| Appearance | Orange to orange-red powder |
| Hue of 1 % solution | Lemon yellow |
| Loss on drying at 135 °C (as sodium salts) | Max. 15.0 % |
| Moisture at 110 °C | Max. 2.0 % |
| Water-insoluble matter | Max. 0.20 % |
| Subsidiary colouring matters | Max. 1.0 % |
| Organic compounds other than colouring matters | Max. 0.5 % |
| Unsulfonated primary aromatic amines (as aniline) | Max. 0.01 % |
| Ether-extractable matter | Max. 0.2 % |
| Arsenic (As) | Max. 1 ppm |
| Lead (Pb) | Max. 1 ppm |
| Mercury (Hg) | Max. 0.05 ppm |
| Cadmium (Cd) | Max. 0.1 ppm |
| Chromium (Cr) | Max. 2 ppm |
| Copper (Cu) | Max. 30 ppm |
| Zinc (Zn) | Max. 50 ppm |
| Heavy metals (as Pb) | Max. 5 ppm |
6. Solution Preparation
Stock solution (1 % w/v): dissolve 1.0 g in about 80 mL purified water and make up to 100 mL. Dilute for use according to your method.
7. Storage & Shelf Life
15–25 °C, dry, tightly closed, protected from sunlight, heat and moisture. Shelf life 36 months from manufacture.
8. References
- Commission Regulation (EU) No 231/2012, Annex: E 102 Tartrazine. Specifications for food additives.
- FAO/WHO JECFA. Tartrazine: Combined Compendium of Food Additive Specifications.
- EFSA ANS Panel (2009). Scientific Opinion on the re-evaluation of tartrazine (E 102). EFSA Journal 7(11):1331.
- Lendrum A.C. (1947). The phloxin-tartrazine method as a general histological stain and for the demonstration of inclusion bodies. J. Pathol. Bacteriol. 59:399–404.
- Ou Z. et al. (2024). Achieving optical transparency in live animals with absorbing molecules. Science 385:eadm6869.
- Horobin R.W., Kiernan J.A. (eds) (2002). Conn's Biological Stains, 10th ed. BIOS Scientific Publishers, Oxford.
Safety Data Summary — Tartrazine
SDS-ASD-640 · Rev 1.0 · November 2026 · Full 16-section SDS available on requestHazard Classification (GHS)
Signal word: Warning
Skin sensitisation, Category 1
H317 May cause an allergic skin reaction.
Skin sensitisation, Category 1
H317 May cause an allergic skin reaction.
Precautionary statements: P261 Avoid breathing dust. P272 Contaminated work clothing should not be allowed out of the workplace. P280 Wear protective gloves. P302+P352 If on skin: wash with plenty of water. P333+P313 If skin irritation or rash occurs: get medical advice. P501 Dispose of contents and container in accordance with local regulations.
Handling & Protection
- Avoid creating and breathing dust. Use with adequate ventilation.
- Wear nitrile gloves, laboratory coat and safety glasses.
- The dye stains skin and surfaces; clean spills promptly with water.
First Aid
- Inhalation: Move to fresh air. Seek medical advice if breathing symptoms occur.
- Skin: Wash with plenty of soap and water. Get medical advice if a rash occurs.
- Eyes: Rinse with water for several minutes. Seek medical advice if irritation persists.
- Ingestion: Rinse mouth. Seek medical advice if you feel unwell.
Poisons Information Centre (Australia): 13 11 26 · Emergency: 000
Storage & Disposal
Store at 15–25 °C, dry, tightly closed and protected from light. Dispose of according to local regulations.
Transport
Not regulated as dangerous goods for road (ADG), sea (IMDG) or air (IATA) transport.
Quality & Certificate of Analysis
ASD-640 · Batch-specific COA available on requestEach batch is supplied with traceable manufacturer test data. A batch-specific Certificate of Analysis is available on request. Please quote the batch number printed on the label.
Typical Batch Results
| Test | Specification | Result |
|---|---|---|
| Pure dye content (E 1 %, 1 cm at 426 nm) | Min. 85.0 % | 85.26 % |
| Appearance | Orange to orange-red powder | Orange-reddish powder |
| Hue of 1 % solution | Lemon yellow | Lemon yellow |
| Loss on drying at 135 °C (as sodium salts) | Max. 15.0 % | 12.95 % |
| Moisture at 110 °C | Max. 2.0 % | 0.92 % |
| Water-insoluble matter | Max. 0.20 % | 0.08 % |
| Subsidiary colouring matters | Max. 1.0 % | 0.42 % |
| Organic compounds other than colouring matters | Max. 0.5 % | 0.38 % |
| Unsulfonated primary aromatic amines (as aniline) | Max. 0.01 % | < 0.01 % |
| Ether-extractable matter | Max. 0.2 % | 0.08 % |
| Arsenic (As) | Max. 1 ppm | < 1 ppm |
| Lead (Pb) | Max. 1 ppm | < 1 ppm |
| Mercury (Hg) | Max. 0.05 ppm | 0.005 ppm |
| Cadmium (Cd) | Max. 0.1 ppm | 0.04 ppm |
| Chromium (Cr) | Max. 2 ppm | < 1 ppm |
| Copper (Cu) | Max. 30 ppm | 3 ppm |
| Zinc (Zn) | Max. 50 ppm | 18 ppm |
| Heavy metals (as Pb) | Max. 5 ppm | < 5 ppm |
Results as reported on the manufacturer's certificate of analysis dated 19/10/2026.