What it is
Copper gluconate is a water-soluble copper salt that supplies copper ions to topical formulations. In cosmetics it functions as a skin-conditioning agent and is sometimes included for its association with copper-dependent enzyme activity in skin. It is used at low concentrations and contributes a pale blue-green color to solutions.
Safety & warnings
Used at low levels in cosmetics, copper gluconate is generally well tolerated. Copper salts can be irritating at higher concentrations, so formulations keep use levels low. It is not a recognized fragrance allergen and is not an oil, so comedogenicity is not a relevant concern.
Origin & sourcing
Manufactured synthetically by reacting gluconic acid (or its salts) with a copper source; gluconic acid itself is typically produced by fermentation of glucose.
Questions everyone asks
What is copper gluconate used for in sunscreen?
It serves as a skin-conditioning agent and a source of bioavailable copper, included at low levels as a supporting ingredient rather than for sun protection.
Is copper gluconate a UV filter?
No. It does not absorb or reflect ultraviolet light and plays no role in a product's sun protection.