Hyaluronic acid's main component is hyaluronic acid, which is classified into several types based on its molecular weight:
1. High molecular weight hyaluronic acid: Molecular weight exceeding 2000 kDa, primarily used for surface hydration and injectable filling and shaping.
2. Medium molecular weight hyaluronic acid: Molecular weight 500-2000 kDa, can partially penetrate the epidermis, commonly used to improve skin elasticity and fine lines.
3. Low molecular weight hyaluronic acid: Molecular weight below 500 kDa, can penetrate the dermis, and has repairing and antioxidant effects.
4. Cross-linked hyaluronic acid: Formed into a three-dimensional structure through chemical bonds, enhancing durability, used for shaping and filling in different areas.
5. Acetylated hyaluronic acid: Enhanced lipid solubility and moisturizing effect through acetyl group modification, suitable for patients with atopic dermatitis.
