Common Name(s): 3,5-dimethoxy-4-hydroxycinnamic acid,sinapinic acid

CAS Number: 530-59-6

DESCRIPTION

What It Does: Provides antioxidant activity with natural uv absorption for combined photoprotection and antioxidant defense.

Why It's Used: Natural uv-absorbing antioxidant from cruciferous sources providing both direct free radical scavenging and uv energy absorption.

How It Works: Two methoxy groups enhance electron-donating capacity for radical scavenging. cinnamate chromophore absorbs uv (290-330nm) via pi-pi transitions. anti-inflammatory via cox-2 inhibition. potential for natural uv filter activity.

Typically Found In: Natural sunscreen boosters,antioxidant serums,photoprotection products

TECHNICAL DETAILS

Primary Category: Active ingredient – phenylpropanoid antioxidant

Secondary Functions: Uv absorption,photoprotection,anti-inflammatory

Application Areas:

Typical Concentration Range: 0.1%–1%

SOURCING & ETHICS

Vegan Status: Yes – from cruciferous plants

Halal Status: Yes

Source Notes: Plant-derived extract or synthetic.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; well-tolerated.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

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

Works Well With: Vitamin c,vitamin e,ferulic acid,spf,other antioxidants

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Sinapic acid's uv absorption maximum (320nm, log ε~4.3) falls in the uvb/uva-ii range, comparable to synthetic uvb filters. unlike synthetic filters, sinapic acid simultaneously provides direct antioxidant protection while absorbing uv, making it a dual-action photoprotective ingredient.

Last Verified: 2026-03-12

Primary Sources: Cosing database,nair et al. sinapic acid uv absorption study