This multifunctional polysaccharide serves as a texture enhancer and skin-soothing agent by forming a breathable, hydrating film. It is frequently utilized to stabilize formulations and reduce the appearance of swelling or redness in sensitive skin.
- INCI Name:
- Dextran
- Chemical/Scientific Name:
- (1→6)-α-D-glucan
- Common Aliases:
- Macrodex, Polyglucin
| Category: | Texture Enhancers |
| Source Origin: | Biotechnological (Microbial Fermentation) |
| Comedogenic Rating: | 0 |
| Primary Industries: | Pharmaceutical, Cosmetic, Food |
| Solubility: | Water-soluble |
At a Glance: Properties & Effects
| Hydration/Moisture | |
| Soothing/Calming | |
| Texture Enhancement | |
| Irritation Risk |
- Primary Benefits: Calms inflammatory responses, improves product spreadability, maintains moisture through film-forming properties, and reduces skin edema (swelling).
- Potential Risks: Extremely low; generally considered non-irritating and non-sensitizing for all skin types.
Biological Action & Cosmetic Profile
Topical polysaccharides of this class function primarily as high-molecular-weight film-formers. By creating a microscopic, permeable matrix on the stratum corneum, they limit transepidermal water loss (TEWL) without the occlusive weight associated with heavy oils or waxes. This structure allows the skin to retain its natural moisture levels while providing a smooth, “velvety” finish to cosmetic products.
Reducing vascular permeability represents another significant biological pathway for this ingredient. In dermatological applications, it has been observed to inhibit the release of certain pro-inflammatory cytokines. This action helps to mitigate skin reactive responses, such as redness and swelling, making it a common inclusion in post-procedure creams or formulas designed for rosacea-prone skin.
Viscosity control is a secondary but vital function. By interacting with the aqueous phase of a formula, these molecules enhance the stability of emulsions and prevent the separation of active ingredients. This ensures a consistent delivery of the product’s benefits throughout its shelf life.
Broader Applications & Origins
Microbial fermentation of Sucrose by the bacterium Leuconostoc mesenteroides provides the standard industrial source for this ingredient. While it is synthesized through biotechnology, the resulting glucan is chemically identical to certain naturally occurring complex sugars. Its long history in the medical field as a plasma volume expander—used to treat shock and blood loss—underscores its high level of biocompatibility and safety.
In the pharmaceutical industry, specific molecular weights are isolated to serve as carriers for drugs, improving their solubility and delivery. This same principle is applied in advanced cosmetic science, where the ingredient is often conjugated with peptides or other sensitive actives to enhance their stability and penetration into the upper layers of the epidermis.
Routine Integration
- Synergies: Works exceptionally well with other humectants like Glycerin and Sodium Hyaluronate. It is also frequently paired with soothing agents such as Panthenol or Allantoin to maximize anti-inflammatory effects.
- Conflicts: No known pharmacological or chemical conflicts exist for this ingredient in topical applications; it is compatible with retinoids, acids, and vitamins.
Clinical Consensus & Safety
The Cosmetic Ingredient Review (CIR) Expert Panel has evaluated Dextran and its derivatives, concluding they are safe for use in cosmetic formulations. Because it is a large molecule that does not penetrate beyond the superficial layers of the skin, the risk of systemic absorption or toxicity is virtually non-existent. Furthermore, clinical testing repeatedly categorizes it as non-comedogenic and non-sensitizing, even when applied to compromised or sensitive skin barriers.
Is Dextran vegan and gluten-free?
Yes. This ingredient is typically produced through bacterial fermentation of sugar beets or sugar cane, making it entirely plant-derived and free from animal byproducts. It is also unrelated to gluten-containing grains.
Why is it included in “anti-puffiness” eye creams?
Its ability to modulate microcirculation and reduce fluid accumulation in the tissues makes it effective at minimizing the appearance of under-eye bags and puffiness caused by inflammation or lack of sleep.