Chelating Agents – Cosmetic Uses in Product Stability and Preservation

What Are Chelating Agents?

Chelating agents are ingredients that bind metal ions and form stable complexes with them. In cosmetic formulations, they can help control trace amounts of metals that may otherwise affect product stability or preservative performance.

Examples include phytic acid, which can be obtained from rice bran, and sodium gluconate, a naturally produced ingredient obtained through the fermentation of glucose.

Cosmetic Applications

Chelating agents can be incorporated into cosmetic formulations to support the effectiveness of preservation systems and improve formulation stability.

Phytic acid is one naturally derived option that can be used to enhance the activity of natural preservatives.

Sodium gluconate is the sodium salt of gluconic acid. It is a white crystalline powder that is highly soluble in water and can function particularly effectively in alkaline and concentrated alkaline solutions.

It forms stable complexes with metal ions including:

• Calcium
• Iron
• Copper
• Aluminium
• Other heavy metals

Sodium gluconate is also resistant to oxidation and reduction in aqueous solutions, including at elevated temperatures.

Chelating Agents and Preservation

Metal ions can influence chemical reactions and may reduce the stability of cosmetic formulations. By binding these ions, chelating agents can support the overall stability of a product and enhance the activity of certain preservative systems.

The original source also notes that very high concentrations of chelating agents have been used for preservative purposes themselves.

Ingredient Information

Ingredient Type: Chelating agents
Examples: Phytic Acid, Sodium Gluconate
Functions: Chelating, formulation stabilisation, preservation support

References

Dweck, Anthony. Handbook of Formulating Natural Cosmetics (Dweck Books 1) (pp. 83-84).