Dipeptide-4 Basic Information

Dipeptide-4 Powder Specification

Dipeptide-4 Solution Specification

Dipeptide-4 (Cys-Gly): glutathione precursor, antioxidant, anti-glycation. Protects skin from oxidative stress & preserves collagen/elastin.

Advantage and Benefit

FAQs

Q1: How does Dipeptide-4 (Cys-Gly) help reduce hyperpigmentation and uneven skin tone?

A: Dipeptide-4 reduces hyperpigmentation primarily through its antioxidant action, which lowers oxidative stress levels that can activate melanocytes. By scavenging ROS and upregulating the skin‘s natural antioxidant defenses, it helps prevent UV‑induced melanin overproduction. Notably, when combined with glutathione (GSH) and γ‑glutamylcysteine (γ‑GC), Dipeptide-4 exhibits a synergistic tyrosinase inhibitory effect, reducing melanin synthesis more effectively than any single component alone. This synergistic combination is specifically claimed in patents for skin‑whitening and pigmentation‑improving compositions.

Q2. What is the mechanism of Dipeptide-4 (L-Cysteinylglycine) as a glutathione precursor and how does it compare to direct glutathione in anti-aging formulations?

A: Dipeptide-4 (L-Cysteinylglycine) is a glutathione precursor via the γ-glutamyl cycle, regenerating glutathione to maintain redox balance. Compared to direct glutathione, it has smaller size (178 Da vs 307 Da) for better penetration, is more stable in formulations, and acts as a direct metabolic intermediate. Clinical evidence supports its antioxidant and anti-glycation benefits, while direct glutathione has limited topical efficacy. For anti-aging leave-on products, Dipeptide-4 is superior due to stability, penetration, and proven activity.

Q3.How stable is Dipeptide-4 (L-Cysteinylglycine) in aqueous skincare formulations, and what are the optimal pH and temperature conditions to preserve its antioxidant and anti-glycation activity?

Dipeptide-4 (L-Cysteinylglycine) is stable in aqueous formulations at pH 5.5-7.0. Avoid strong acids (pH<3.5) and strong bases. Add below 40°C; prolonged heating degrades activity. Store raw material at 2-8°C for up to three years. Avoid high-valent metal ions like Fe³⁺ and Cu²⁺. Following these conditions preserves full antioxidant and anti-glycation activity throughout shelf life.

Q4.Can Dipeptide-4 (L-Cysteinylglycine) be combined with other anti-aging peptides (e.g., Matrixyl, Argireline) or vitamin C derivatives without losing efficacy? What synergistic effects have been reported?

Yes, Dipeptide-4 (L-Cysteinylglycine) combines well with other actives. With vitamin C derivatives (e.g., AA2G), it provides synergistic dual-pathway antioxidant effects. With Argireline, it targets dynamic and static wrinkles. With Matrixyl, mechanisms complement: Matrixyl stimulates collagen, Dipeptide-4 offers antioxidant and anti-glycation benefits. With niacinamide, it enhances anti-glycation and improves skin tone. Use stabilized vitamin C derivatives instead of pure L-ascorbic acid. Dipeptide-4 is highly versatile and synergistic.

Q5.What is the recommended dosage range of Dipeptide-4 (L-Cysteinylglycine) for visible anti-glycation and antioxidant benefits in leave-on products, and are there any known safety or irritation concerns for sensitive skin?

For leave-on products, recommended dosage is 0.1%-1.0% for anti-aging serums/creams; for sensitive skin, 0.05%-0.2%. Minimum effective is 0.05%. Safety: 2023 CIR concludes safe for cosmetic use. Listed in China (max historical use 0.005% leave-on) and Japan. Most skin types tolerate well. Rare mild redness with overuse. Patch test for very sensitive skin. 0.05%-1.0% effective and safe; start at 0.05% for sensitive skin.