Science
Mechanism of Action
As a cationic peptide, Polylysine acts primarily as a broad-spectrum preservative by electrostatically adsorbing to negatively charged microbial cell surfaces, disrupting their outer membranes and inhibiting proliferation. Specifically for acne-prone skin, it modulates the microbiome by preferentially interacting with and limiting the growth of acneic *Cutibacterium acnes* strains while preserving beneficial flora. Beyond antimicrobial action, Polylysine exhibits antioxidant and film-forming characteristics, enhancing the stability and moisturizing efficacy of co-formulated actives such as Vitamin C, and contributing to sustained skin hydration.
Research
Clinical Evidence
Medium confidenceN/A
Key findings
- 01 Poly-L-lysine dendrimers, when formulated with Vitamin C, significantly enhanced Vitamin C's stability and moisturizing efficacy. Physiological tests demonstrated a 66.2% increase in skin hydration after 3 hours with third-generation Poly-L-lysine/Vitamin C formulations.
- 02 A polylysine dendrimer was developed as an anti-acne strategy to modulate the skin microbiome. It preferentially interacted with negatively charged acneic strains of *Cutibacterium acnes*, limiting their proliferation and helping restore skin homeostasis.
Transparency
Dusting Analysis
The Formula
Formulation
Stability
Polylysine, particularly ε-polylysine, is highly heat stable and maintains its efficacy across a broad pH range, specifically noted to be effective between pH 3 and 9, with optimal performance typically observed from pH 5 to 8.
Synergies
- Vitamin C (enhances stability and moisturizing efficacy)
Conflicts
- anionic surfactants
Safety
Safety Profile
Polylysine has not been specifically assessed by the Cosmetic Ingredient Review (CIR) Expert Panel or the Scientific Committee on Consumer Safety (SCCS) for cosmetic use. However, ε-polylysine (free form) has achieved GRAS (Generally Recognized As Safe) certification from the US FDA as a food additive, indicating a high safety profile. INCIDecoder data suggests low irritancy.
Your Skin
Skin Compatibility
Our Assessment
Verdict
Polylysine is a valuable, multi-functional ingredient that enhances product preservation, supports a balanced skin microbiome, boosts hydration, and optimizes the performance of other key actives, making it highly beneficial for diverse skin concerns.
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