Yellow solution of curcumin becomes and intense red color with solutions containing boron
name: Curcumin forms intense red complex with boron
The Home Scientist 019 - Testing for boron with curcumin (turmeric)
Wear eye protection and lab gloves.
Always follow general safety
recommendations. Please note that conducting chemistry
experiments you must comply with the relevant legal procedures in
2C21H20O6 + H3BO3 → [B(C21H19O6)2]OH + 2H2O
- Prepare a set of water solutions of sodium tetraborate decahydrate of different concentrations. You can do this by a serial dilution of a known initial concentration solution. Place these solutions in wells of the test-plate.
- Dissolve some curcumin in ethanol.
- Add 3 drops in each of the wells.
Boron from boric acid ions forms a red complex called rosocyanine with curcumin. In this complex one atom of boron coordinates with two molecules of curcumin. The color of the obtained solution depends on the concentration of boron. This reaction may be used for detecting boron in water samples during ecology monitoring.