Hyaluronic acid

Hyaluronic acid is a linear polysaccharide of high molecular weight, naturally occurring in the human body. It is applied here as a connective tissue organizer and hydrating substance on the basis of its status as the most hydrating polymer known

The enormous water-binding capacity of hyaluronan is an essential characteristic influencing its biological effects, and , as it is a naturally occuring substance, Hyaluronic acid is free of immunogenic activity, and is a non-toxic and non-irritating substance.

Skin hydration is the cornerstone of the anti-aging concept for the simple reason that adequate water content is essential for the proper functioning of all of the human body’s structures. With a certain degree of exaggeration, ensuring hydration is a basic condition for the normalisation of the internal mechanisms affecting skin aging.

Generally Hyaluronic acid is non-irritating, non-cytotoxic and non-phototoxic

How Does Hyaluronic acid work?

Hyaluronic acid influences the internal processes happening in the skin in two ways.

The first is the formation of a film on the skins surface. This is a product of the physico-chemical properties of hyaluronan. The film hydrates the surface of the skin and prevents water loss. Effective and optimal hydration helps to maintain the epidermal barrier function and thereby contributes to suitable conditions for the cells of the epidermis and dermis. This aids the reduction in environmental influence, lowering cell stress.

The skin is soothed, due to the creation of a cool surface film and by the modulation of the environment for skin cells.

Skins texture can be improved mainly due to the ability to form a hydrating film on the surface which reaffirms the strong links between the individual signs of aging.

This moisturising film essentially macerates the stratum corneum and thus indirectly affects the disruption of intercellular structures in the stratum corneum and the integrity of the epidermis as a whole.

How to Use Hyaluronic acid

Commonly used between 1% and 10% in final formulations.

Hyaluronic acid is water soluble and thus cannot be directly mixed with oil. It can be added to creams and lotions as part of the normal production process. When used in Creams and Lotions, it should be added to the cool down stage of the production.

Heating to 90c for 45 minutes can lead to the molecular weight decrease of up to 20%, so heat should always be avoided as much as possible during processing.

Sensitive to both low and high pH. Extreme values lead to molecular weight decrease, which is further enhanced by product heating. Use a pH tolerant preservative in final formulation of hyaluronic acid formulations.

Hyaluronic acid is incompatible with cationic substances e.g. surfactants or polymers (Polyquarternium-4, Polyquarternium-10 etc.)

Solubility of Hyaluronic acid

Hyaluronic acid is fully soluble in water. It is also soluble in a mixture of ethylalcohol, isopropylalcohol propylene glycol and butylene glycol with water up to a ration of 1:1.

Hyaluronic acid is not soluble in non-water miscible solvents