Common Name(s): Acetyl proline,acetyl proline,n-acetylproline,collagen amino acid active

CAS Number: N/a

DESCRIPTION

What It Does: Provides n-acetyl proline as a cell-permeable collagen precursor — the acetyl group facilitates cellular uptake while the proline backbone provides substrate for prolyl hydroxylase-mediated hydroxyproline synthesis in procollagen.

Why It's Used: Acetyl proline is selected over free proline for its cell permeability — the n-acetyl group provides neutral pka and lipophilicity for cellular uptake while the proline backbone directly supplies the rate-limiting gly-pro-hyp collagen sequence substrate for triple helix formation.

How It Works: Acetyl proline → cellular uptake (neutral acetamide → improved membrane crossing vs zwitterionic free proline) → intracellular proline → prolyl hydroxylase substrate → hydroxyproline → collagen gly-pro-hyp repeat → triple helix stability.

Typically Found In: Anti-aging,collagen support

TECHNICAL DETAILS

Primary Category: Active ingredient – peptide

Secondary Functions: Collagen synthesis,anti-aging

Application Areas:

Typical Concentration Range: 0.1%–5%

SOURCING & ETHICS

Vegan Status: Yes

Halal Status: Yes

Source Notes: Synthetically produced via solid-phase peptide synthesis (spps).

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating at recommended concentrations.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Retinoids,niacinamide,vitamin c,hyaluronic acid

Avoid Combining With: Strong acids below ph 3.5; oxidising agents

SCIENTIFIC NOTE

Acetyl proline's neutral form provides ~3× better fibroblast cellular uptake than free proline at physiological ph — the acetyl group neutralising the amine charge that limits membrane permeation.

Last Verified: Cosing database,acetyl proline n-acetylproline collagen amino acid review

Primary Sources: 2026-03-22