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Common Name(s): Amphoteric betaine surfactant,mild co-surfactant,conditioning foam enhancer
CAS Number: N/a
DESCRIPTION
What It Does: Boosts foam, reduces irritation of co-formulated anionic surfactants through mixed micelle charge dilution, and provides mild conditioning to skin and hair from zwitterionic surface interactions.
Why It's Used: Betaine co-surfactants are the standard mildness-enhancing component in shampoos and body washes โ 2โ5% cocamidopropyl betaine provides 20โ40% irritation reduction in sls-based formulations through mixed micelle charge dilution.
How It Works: At cosmetic ph 5โ7, betaine's quaternary ammonium positive charge and carboxylate negative charge provide net-zero zwitterionic character. mixed micelles formed with anionic surfactants have lower net surface charge density โ reducing protein-binding electrostatic driving force and providing the mildness enhancement. substantive conditioning from cationic character below isoelectric point.
Typically Found In: Shampoos,body wash,mild cleansers
TECHNICAL DETAILS
Primary Category: Active ingredient โ cosmetic active
Secondary Functions: Skin conditioning
Application Areas:
Facial Skincare
Body Care
Hair Care
Beard Care
Color Cosmetics (Makeup)
Dietary/Oral Supplements
Typical Concentration Range: 3%โ20%
SOURCING & ETHICS
Vegan Status: Conditional - feedstock declaration required
Halal Status: Unverified - feedstock declaration required (plant, animal and petrochemical routes all exist)
Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier. [audit 2026-07-29 rev2: origin-dependent: the same inci exists in plant, animal and petrochemical versions and the name does not discriminate. determination requires shariah-panel sign-off.]
SKIN COMPATIBILITY
Irritancy Rating: 1/5 โ very low
Comedogenicity Rating: 0/5 โ non-comedogenic
Sensitivity Concerns: Well-tolerated by most skin types.
Safe for Sensitive Skin: Yes
SAFETY & COMPATIBILITY
Safety Profile: Good safety profile at recommended concentrations. ewg score: 1โ2.
Works Well With: Standard skincare actives
Avoid Combining With: No known significant incompatibilities
SCIENTIFIC NOTE
Mixed micelle formation between betaine and sls changes the effective hlb and surface charge of the micelle surface โ the charge dilution effect reducing protein denaturing activity follows a non-linear relationship with betaine fraction, with maximum benefit achieved at 30โ40% betaine in the surfactant blend.
Last Verified: 2026-03-12
Primary Sources: Cosing database,behenamidopropyl betaine amphoteric betaine review