High molecular weight esthetic compositions
Described are high molecular weight glycosaminoglycan (GAG) hydrogel compositions comprising GAGs covalently crosslinked with a carbohydrate crosslinker, and methods of making the high molecular weight GAG hydrogel compositions. Further described are methods of using the high molecular weight glycosaminoglycan (GAG) hydrogel compositions for reparative or plastic surgery, esthetic dermatology, facial contouring, body contouring, and gingival augmentation.
1. A method of preparing a hydrogel comprising crosslinked glycosaminoglycan (GAG) molecules, comprising crosslinking a GAG having a molecular weight of 2.1 to 10 MDa with a crosslinker, to obtain a glycosaminoglycan hydrogel crosslinked by amide bonds, wherein:
the GAG is hyaluronic acid (HA); the crosslinker is a di- or multinucleophile functional crosslinker comprising a spacer group selected from the group consisting of di-, tri-, tetra-, and oligosaccharides;
the concentration of GAG is between 2% to 10% (w/w); and
the molar ratio of the crosslinker to GAG is less than or equal to 2 mol % per GAG disaccharide.
2. The method of preparing a hydrogel according to claim 1 , wherein
if the GAG concentration is between 2% to 4.5% (w/w), then the concentration of crosslinker is between 0.8 to 2 mol % per GAG disaccharide; and
if the GAG concentration is between 4.6% to 5.9% (w/w), then the concentration of crosslinker is between 0.5 to 0.8 mol % per GAG disaccharide; and
if the GAG concentration is between 6% to 10% (w/w), then the concentration of crosslinker is between 0.3 to 0.5 mol % per GAG disaccharide.
3. The method according to claim 1 , wherein the di- or multinucleophile functional crosslinker is diaminotrehalose (DATH).
4. The method according to claim 1 , wherein the crosslinking comprises:
(1) providing a solution of the glycosaminoglycan (GAG) molecules;
(2) activating carboxyl groups on the glycosaminoglycan molecules with a coupling agent to form activated glycosaminoglycan molecules;
(3) crosslinking the activated glycosaminoglycan (GAG) molecules via their activated carboxyl groups using a di- or multinucleophile functional crosslinker to obtain a glycosaminoglycan hydrogel crosslinked by amide bonds.
5. The method according to claim 4 , wherein the coupling agent is a triazine-based coupling agent.
6. The method according to claim 1 , wherein the crosslinking is performed at a pH of 6.0-8.0.
7. The method according to claim 1 , further comprising formulating the crosslinked hydrogel to a final glycosaminoglycan (GAG) concentration of 10-45 mg/mL.
8. The method according to claim 1 , further comprising sterilizing the crosslinked hydrogel.
9. The method according to claim 1 , wherein the GAG has a molecular weight of 2.1-3.5 MDa.
10. The method according to claim 1 , wherein the concentration of the GAG is between 3-5% (w/w).
11. The method according to claim 1 , wherein the molar ratio of crosslinker to GAG is between 0.9-1.1 mol % per GAG disaccharide.
12. The method according to claim 1 , wherein the hyaluronic acid (HA) having a molecular weight of 2.1-3.5 MDa and the crosslinker is diaminotrehalose (DATH), and further wherein the concentration of HA is between 3-5% (w/w) and the molar ratio of DATH to HA is between 0.9-1.1 mol % per GAG disaccharide.