Los rellenos dérmicos de HA tienen eficacia comprobada para contornear y dar volumen a los tejidos blandos., y puede usarse para tratar líneas finas y arrugas en la cara.. Their longevity is enhanced by a critical cross-linking process that links HA molecules together, forming a threedimensional network that resists enzymatic degradation. HA-based fillers are available in many formulations and product brands, ranging from highly cross-linked (JUVEDERM) to less cross-linked products (BELOTERO, TEOSYAL RHA). Injectability attributes, such as viscosity, módulo elástico (GRAMO'), and cohesivity, vary widely among and within product selections, with significant impact of the degree of cross-linking, concentración de HA, local anesthetic lidocaine content, needle gauge size, and more.
Shandong Light year biotechnology have unique technology of monophase cross link gel, It provides technical support for producing excellen fillers,the present invention provides highly injectable, long-lasting hyaluronic acid-based hydrogel dermal filler compositions made with a di-amine or multiamine crosslinker in the presence of a carbodiimide coupling agent. The compositions are substantially optically transparent and exhibit reduced or no perceptible blue discoloration when administered into a patient’s skin. In some embodiments, the crosslinker is 4-aminobutyric acid (4 AA). Unlike diamines that can only crosslink two HA chains, 4 AA has four amine functional groups and, therefore, can significantly enhance crosslinking efficiency in the resulting hydrogels. In addition, the crosslinking efficiency results in robust hydrogels that can be sterilized by moist steam without imparting structural damage to the gels.
The invention also provides methods for introducing the above-described hyaluronic acid-based dermal filler compositions into a patient’s skin in a treatment area such as a tear trough region, glabellar line, periorbital line, or forehead region, and inducing the desired cosmetic effect. The injections may be performed by a physician or other health care provider using a syringe and other conventional medical equipment.