IMPLANTABLE HYALURONIC ACID/COLLAGEN COMPOSITIONS

1 . A crosslinked macromolecular matrix comprising:

a hyaluronic acid component;

a collagen component derived from collagen type I or collagen type III;

wherein the hyaluronic acid component is crosslinked to the collagen component by a crosslinking component; and

wherein the crosslinking component comprises a plurality of crosslink units, wherein at least a portion of the crosslink units comprise an ester bond or an amide bond.

2 . The crosslinked macromolecular matrix of claim 1 , having a weight ratio of the hyaluronic acid component to the collagen component of about 0.5 to about 7.

3 . The crosslinked macromolecular matrix of claim 1 , wherein the hyaluronic acid component has an average molecular weight of about 500,000 daltons to about 10,000,000 daltons.

4 . The crosslinked macromolecular matrix of claim 1 , further comprising an aqueous liquid comprising water, sodium chloride at a concentration of about 100 mM to about 200 mM, potassium chloride at a concentration of about 2 mM to about 3 mM, and phosphate buffer at a concentration of about 5 mM to about 15 mM, wherein the pH of the liquid is about 7 to about 8.

5 . A composition comprising:

a hyaluronic acid;

a collagen;

a water-soluble coupling agent; and

a buffer;

wherein the composition is an aqueous solution.

6 . The composition of claim 5 , further comprising an activating agent comprising a triazole, a fluorinated phenol, a succinimide, or a sulfosuccinimide.

7 . The composition of claim 5 , wherein the hyaluronic acid component has an average molecular weight of about 1,000,000 daltons to about 5,000,000 daltons.

8 . The composition of claim 5 , wherein the collagen is collagen type I.

9 . The composition of claim 5 , wherein the collagen is collagen type III.

10 . The composition of claim 5 , wherein the buffer comprises 2-(N-morpholino)ethanesulfonic acid.

11 - 18 . (canceled)

19 . An injectable composition for aesthetic and reconstructive uses made by a process comprising the steps of:

dissolving a hyaluronic acid and a collagen in an aqueous solution to form an aqueous pre-reaction solution, wherein the aqueous pre-reaction solution further comprises a salt or has a pH less than about 4; and

modifying the aqueous pre-reaction solution to form a crosslinking reaction mixture comprising

the hyaluronic acid,

the collagen,

a water soluble carbodiimide,

an N-hydroxysuccinimide or an N-hydroxysulfosuccinimide, and

the salt;

wherein the crosslinking reaction has a higher pH than the aqueous pre-reaction solution; and

allowing the crosslinking reaction mixture to react to thereby crosslink the hyaluronic acid and the collagen; and

sizing the crosslinked hyaluronic acid and collagen to obtain an injectable composition.

20 . A soft tissue aesthetic product comprising:

an aesthetic device having a form suitable for injecting or implanting into human tissue; and

a label comprising instructions to inject or implant the aesthetic device into human tissue;

wherein the aesthetic device comprises a crosslinked macromolecular matrix comprising:

a hyaluronic acid component; and

a collagen component;

wherein the hyaluronic acid component is crosslinked to the collagen component by a crosslinking component; and

wherein the crosslinking component comprises a plurality of crosslink units, wherein at least a portion of the crosslink units comprise an ester bond or an amide bond.

21 . The product of claim 20 , wherein the collagen component comprises collagen type I or collagen type III.

22 . The product of claim 20 , wherein crosslinked macromolecular matrix has a weight ratio of the hyaluronic acid component to the collagen component of about 1 to about 3.

23 . A method of improving an aesthetic quality of an anatomic feature of a human being comprising:

injecting or implanting an aesthetic device into a tissue of the human being to thereby improve the aesthetic quality of the anatomic feature;

wherein the aesthetic device comprises a crosslinked macromolecular matrix comprising:

a hyaluronic acid component; and

a collagen component;

wherein the hyaluronic acid component is crosslinked to the collagen component by a crosslinking component; and

wherein the crosslinking component comprises a plurality of crosslink units, wherein at least a portion of the crosslink units comprise an ester bond or an amide bond.

24 . The method of claim 23 , wherein the hyaluronic acid component has an average molecular weight of about 1,000,000 daltons to about 3,000,000 daltons.