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Polyquaternium-51

Polyquaternium-51 (Lipidure) — a unique polymer based on phospholipid structure (MPC) that mimics the outer layer of cell membranes. Exceptional hydration, protection against dehydration, and biocompatibility make it one of the most effective moisturizing polymers in luxury cosmetics.

Phospholipid structureHydrationMembrane protectionBiocompatibility
✓ Safe
Comedogenic Rating
0/5
Irritation Potential
0/5

What is it?

Polyquaternium-51 (INCI: Polyquaternium-51) — cationic polymer based on 2-methacryloyloxyethyl phosphorylcholine (MPC). Structure: side phosphorylcholine groups → phospholipid mimicry. MW: ~50,000-200,000 Da. Water-soluble. Moisturizing mechanism: phosphorylcholine groups bind water structurally (as in cell membranes) → excessive and prolonged moisture retention; forms a protective layer on the surface of cells and skin. Feature: not just a film-forming humectant, but a biomimetic structure of the membrane. Compatible with ionic and non-ionic components.

Luxury moisturizing serums and creams, products for sensitive eyes and mucous membranes, contact lenses (medical use), products for protecting and restoring damaged skin.

Key Benefits

✦
Phospholipid mimicry — exceptional hydration at the cellular level
Polyquaternium-51 has a unique structure of phosphorylcholine groups — identical to the polar head of phosphatidylcholine (the most common phospholipid in cell membranes). Mechanism: MPC polymer interacts with lipid membranes, integrating into them as "its own" — does not disrupt membrane integrity. Moisture retention: phosphorylcholine groups bind water molecules much more effectively than hyaluronic acid by several parameters. Clinical data: Lipidure/PQ-51 at 0.1-0.5% demonstrates a higher moisturizing score than HA at equivalent concentrations in some studies.
◈
Protection against dehydration and anti-friction action
Polyquaternium-51 forms a hydrophilic protective layer on the skin surface that: reduces TEWL (transepidermal water loss); protects against mechanical irritation (anti-friction action); stabilizes the lipid barrier. Especially effective after procedures (laser, peeling, micro-needling) — protection of the damaged barrier. Medical use: solutions for contact lenses (AQuify, Blink) — protects the cornea without irritation. The gentlest moisturizing polymer for sensitive areas (around the eyes, lips).
✧
Biocompatibility and ideal tolerance
MPC polymers (polyquaternium-51) — the most studied biocompatible polymers in medicine and cosmetics. Do not cause allergic reactions, do not irritate mucous membranes, hypoallergenic. Comparison with hyaluronic acid: PQ-51 is more stable (does not degrade by hyaluronidase), better duration of moisturizing effect. Safe for ocular use. Ideal for baby cosmetics, sensitive skin, eye area products. Uniquely: does not alter the skin microbiome, does not suppress normal flora.

Suitable for

Sensitive and atopic skinAreas around the eyesAll skin types

Main Actions

✓ Phospholipid mimicry — cellular hydration✓ Barrier protection and reduction of TEWL✓ Ideal biocompatibility and tolerance
Polyquaternium-51: Lipidure and price quality

Polyquaternium-51 = Lipidure (trade name, NOF Corporation, Japan). One of the most expensive cosmetic polymers — predominantly found in luxury and medical-grade products. Effective concentration: 0.1-1%. Water-soluble, to be introduced into the aqueous phase at any temperature. INCI: Polyquaternium-51. Do not confuse with Polyquaternium-10, -11 (less specific cationic polymers). Synergy with hyaluronic acid: complementary hydration of different types.

Frequently Asked Questions

What does Polyquaternium-51 do for skin?
Luxury moisturizing serums and creams, products for sensitive eyes and mucous membranes, contact lenses (medical use), products for protecting and restoring damaged skin.
Who should use Polyquaternium-51?
Polyquaternium-51 is suitable for: Sensitive and atopic skin, Areas around the eyes, All skin types.
Are there any warnings about Polyquaternium-51?
Polyquaternium-51 = Lipidure (trade name, NOF Corporation, Japan). One of the most expensive cosmetic polymers — predominantly found in luxury and medical-grade products. Effective concentration: 0.1-1%. Water-soluble, to be introduced into the aqueous phase at any temperature. I

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