Pure L-Ascorbic Acid (native Vitamin C) remains a gold-standard antioxidant in skincare, yet it suffers from fatal formulation drawbacks: poor stability, limited skin penetration, and high irritation risk. As a highly optimized Vitamin C derivative, 3-O-Ethyl Ascorbic Acid (VC Ethyl Ether / EAA) solves these pain points through molecular modification. It delivers consistent whitening, robust antioxidant protection, and excellent formulation compatibility with minimal skin irritation, becoming a mainstream active for modern daily skincare and brightening formulations.
1. What Is VC Ethyl Ether? Chemical Profile & Core Properties
3-O-Ethyl Ascorbic Acid is an ether-modified, amphiphilic prodrug of Vitamin C. By grafting an ethyl group onto the 3-position hydroxyl of the Vitamin C molecular structure, the ingredient locks active molecular activity and effectively avoids oxidative inactivation. It features typical amphiphilic characteristics with excellent water solubility and slight oil solubility, enabling flexible application in various aqueous and emulsion cosmetic systems.
| Parameter | Specification |
|---|---|
| INCI Name | 3-O-Ethyl Ascorbic Acid |
| CAS No. | 86404-04-8 |
| Molecular Formula | C₈H₁₂O₆ |
| Molecular Weight | 204.18 |
| Appearance | White crystalline powder |
| Solubility | Excellent water solubility, slightly soluble in oil phase (amphiphilic) |
| Purity | ≥99.0% (HPLC) |
2. Formulation Pain Points of Native VC & EAA’s Core Advantages
2.1 Limitations of Traditional L-Ascorbic Acid
- Poor stability: Easily oxidized, yellowed and inactivated under light, heat and air exposure
- Weak transdermal absorption: Pure water-soluble structure cannot efficiently cross the skin lipid barrier
- High irritation: Only stable under extremely low pH (<3.5), easily causes stinging and redness
2.2 Optimized Performance of VC Ethyl Ether
- Superior stability: Resists oxidation, acid, alkali and high temperature; remains stable at 45°C for 60 days without discoloration
- Improved skin penetration: Amphiphilic property promotes stratum corneum crossing and dermal layer delivery
- Mild and low-irritation: Stable at pH 6.0–7.0, compatible with normal skin pH, suitable for sensitive skin formulations
3. Mechanism of Action (Skin Whitening & Antioxidation)
After penetrating the skin barrier, VC Ethyl Ether is enzymatically decomposed to release active Vitamin C, exerting multi-dimensional skin-benefiting effects including melanin inhibition, free radical scavenging and collagen promotion.
3.1 Dual Melanogenesis Inhibition Mechanism
- Direct inhibition: Suppresses tyrosinase activity, blocking the core enzymatic reaction of melanin synthesis
- Source regulation: Activates the Nrf2 antioxidant pathway, inhibits UVA-induced ROS overflow, and down-regulates POMC/α-MSH inflammatory signaling, reducing melanin production at the source
3.2 Powerful Antioxidant Protection
VC Ethyl Ether directly scavenges excess free radicals in skin tissue (DPPH EC50 = 0.0159 mg/ml). Meanwhile, it up-regulates endogenous antioxidant enzymes including HO-1, γ-GCLC and NQO-1, building a long-term antioxidant defense system to relieve photoaging and oxidative damage.
3.3 Collagen Synthesis Support
As an essential cofactor for prolyl hydroxylase, EAA effectively promotes collagen synthesis and cross-linking, repairs damaged skin cells, improves skin firmness and reduces fine lines caused by oxidation aging.
4. Clinical & In-Vitro Efficacy Data
| Test Item | Efficacy Result |
|---|---|
| Tyrosinase Inhibition | In vitro testing showed 2% EAA achieved nearly 50% melanin inhibition, comparable to or exceeding the reference standard kojic acid (5 mg/ml) in the same assay; IC50 = 3.6 mg/ml |
| Human Skin Brightening Test | 4% EAA formulation significantly increases skin ITA° value after 28 days of continuous use |
| Antioxidant Capacity | DPPH radical scavenging rate reaches 73.9%, EC50 = 0.0159 mg/ml |
| Collagen Activity | 0.05% EAA shows equivalent collagen-promoting effect to 10 ng/ml TGF-β1 |
| Melanin Reduction | 30% EAA serum reduces epidermal melanin content by 15.52%–17.10% in 4-day reconstructed skin model test |
5. Safety & Toxicology Profile
VC Ethyl Ether is a fully verified safe cosmetic active ingredient with low irritation and no sensitization risk, suitable for long-term daily skincare formulas.
| Safety Test | Result |
|---|---|
| Acute Oral Toxicity | LD₅₀ > 2000 mg/kg (low toxicity) |
| Human Skin Irritation | 10% EAA concentration shows non-irritating result in human patch test |
| Skin Sensitization | Non-sensitizing (CIR & SCCS approved) |
| Genotoxicity | Ames test negative, non-mutagenic |
| Pregnancy Safety | Safe for conventional cosmetic dosage |
6. Global Regulatory Compliance
| Region | Regulatory Status |
|---|---|
| China | IECIC included (#00050), permitted for cosmetic use |
| South Korea | Functional ingredient approved (KFDA 2001-15) |
| European Union | CosIng listed & REACH registered |
| Japan & Global Market | Widely approved and applied in cosmetic formulations |
7. VC Ethyl Ether vs. L-Ascorbic Acid (Core Comparison)
| Feature | VC Ethyl Ether (EAA) | L-Ascorbic Acid (Native VC) |
|---|---|---|
| Stability | High stability, anti-light/heat/oxidation | Extremely unstable, easy to yellow and deactivate |
| Solubility | Excellent water solubility, slightly soluble in oil | Only water-soluble |
| Skin Penetration | Efficient transdermal delivery | Poor penetration efficiency |
| Irritation Level | Low irritation, suitable for sensitive skin | High irritation, strict pH limitation |
| Formulation pH Range | 3.5–6.5 (flexible & friendly) | Strictly below 3.5 |
For a full comparison including VC-IP (Ascorbyl Tetraisopalmitate), see our [Vitamin C Derivatives Comparison].
8. Frequently Asked Questions
Q1: Does VC Ethyl Ether work directly on the skin?
A: EAA is an amphiphilic Vitamin C prodrug. It stably penetrates the skin and is enzymatically converted into active L-Ascorbic Acid, delivering sustained whitening and antioxidant effects with longer acting time than pure VC.
Q2: Is EAA suitable for sensitive skin formulations?
A: Yes. Compared with native Vitamin C, EAA eliminates extreme pH requirements and significantly reduces skin irritation risk. It is the preferred mild brightening VC derivative for sensitive skincare.
Q3: What is the standard usage dosage?
A: The recommended dosage is 0.5%–2.0% for conventional brightening formulas; up to 3.0% for high-efficiency customized formulations (stability testing is required for high concentrations).
Q4: What is the shelf life of VC Ethyl Ether raw material?
A: 3 years when sealed, stored in cool, dry and light-proof conditions.
Resources & Technical Support
Looking for free samples, TDS, SDS, COA documents or customized formulation solutions? Contact our professional R&D and technical team.
Related Reading: [VC Ethyl Ether Formulation Guide] | [Vitamin C Derivatives Comparative Analysis]