Hyaluronic Acid

Hyaluronic acid is a polysaccharide naturally present in the skin, widely studied in cosmetics for its hydrating properties. Its molecular structure gives it a water retention capacity documented in scientific literature.
In INCI lists, the salt form of hyaluronic acid (Sodium Hyaluronate) is more commonly found than hyaluronic acid itself: both forms have similar cosmetic application properties, with the salt form being more stable in formulation.
The structure of hyaluronic acid can be modified to adapt its properties. Molecular weight plays a key role: high molecular weight hyaluronic acid is scientifically associated with surface hydration and forming a comfortable film; low molecular weight hyaluronic acid, smaller in size, is linked to action in the upper layers of the epidermis, contributing to longer-lasting hydration.

In the Multi-Active Serum, five complementary forms are present:
High molecular weight hyaluronic acid, scientifically linked to surface hydration and immediate comfort effect.
Low molecular weight hyaluronic acid, smaller in size, scientifically linked to action in the upper epidermal layers for lasting hydration.
Crosslinked hyaluronic acid (multiple chemically linked chains), associated with forming a comfortable surface film and prolonged hydration sensation.
Acetylated hyaluronic acid, with some alcohol groups replaced by acetyl groups, scientifically linked to better water affinity and supporting skin comfort.
Plant-based hyaluronic acid (biosourced by fermentation), a natural alternative to biotechnological forms with comparable hydrating properties.

Sources: Pilot Comparative Study of the Topical Action of a Novel, Crosslinked Resilient Hyaluronic Acid on Skin Hydration and Barrier Function, Journal of Drugs in Dermatology, 2016; Acetylated Hyaluronic Acid: Enhanced Bioavailability and Biological Studies, BioMed Research International, 2014; The anti-wrinkles properties of sodium acetylated hyaluronate, Journal of Cosmetic Dermatology, 2021.