Simple adhesive coacervates and methods of making and using thereof

1. An adhesive produced by the process comprising

(a) preparing a simple adhesive coacervate comprising (1) a polyelectrolyte, wherein the polyelectrolyte comprises a polyanion or polycation but not a combination thereof, the polyeletrolyte comprises at least one crosslinking group, and wherein a photoinitiator and optionally a co-initiator are covalently attached to the polycation and/or polyanion, (2) a sufficient amount of a complimentary counterion to produce a simple adhesive coacervate, and (3) a polymerizable monomer, a water-insoluble filler, or a combination thereof; and

(b) crosslinking the simple adhesive coacervate to produce the adhesive.

2. The adhesive of claim 1 , wherein the polycation comprises electrostatically associated block copolymers, wherein the block co-polymers comprise alternating polycationic blocks and polyanionic blocks, and the polycation has a net positive charge at the pH the simple adhesive coacervate is formed.

3. The adhesive of claim 1 , wherein the polycation comprises a polysaccharide, a protein, a synthetic polyamine, or a synthetic polypeptide.

4. The adhesive of claim 1 , wherein the polycation comprises an amine-modified natural polymer.

5. The adhesive of claim 1 , wherein the polyanion comprises electrostatically associated block copolymers, wherein the block co-polymers comprise alternating polycationic blocks and polyanionic blocks, and the polyanion has a net negative charge at the pH the simple adhesive coacervate is formed.

6. The adhesive of claim 1 , wherein the polyanion comprises a polysaccharide, a protein, or a synthetic polypeptide.

7. The adhesive of claim 1 , wherein the polyanion comprises one or more sulfate, sulfonate, carboxylate, borate, boronate, phosphonate, phosphate groups, or any combination thereof.

8. The adhesive of claim 1 , wherein the polyeletrolyte comprises a polyanion and the complimentary counterion comprises at least one multivalent metal cation comprising one or more divalent cations, one or more transition metal ions, or rare earth metal ions.

9. The adhesive of claim 1 , wherein the adhesive further comprises one or more bioactive agents.

10. A substrate comprising an adhesive of claim 1 on at least one surface of the substrate.

11. A method for modifying the one or more surface properties of a substrate, the method comprising applying to the substrate surface a simple adhesive coacervate prepared by combining (1) a polyelectrolyte, wherein the polyelectrolyte comprises a polyanion or polycation but not a combination thereof, the polyeletrolyte comprises at least one crosslinking group, and wherein a photoinitiator and optionally a co-initiator are covalently attached to the polycation and/or polyanion (2) a sufficient amount of a complimentary counterion to produce a simple adhesive coacervate, and (3) a polymerizable monomer, a water-insoluble filler, or a combination thereof, wherein a photoinitiator and optionally a co-initiator are covalently attached to the polycation and/or polyanion.

12. The adhesive of claim 3 , wherein the protein comprises a recombinant protein.

13. The adhesive of claim 6 , wherein the polysaccharide comprises a hyaluronate, arabic gum, an alginate, chondroitin sulfate, dermatan, dermatan sulfate, heparan sulfate, or any combination thereof.

14. The adhesive of claim 1 , wherein the polyanion comprises a polyphosphate compound.

15. The adhesive of claim 1 , wherein the polyanion comprises a polyacrylate comprising one or more pendant phosphate groups.

16. The adhesive of claim 1 , wherein the polyanion comprises a polymer comprising at least one fragment comprising the formula X

wherein R 4 is hydrogen or an alkyl group;

n is from 1 to 10;

Y is oxygen, sulfur, or NR 30 , wherein R 30 is hydrogen, an alkyl group, or an aryl group;

Z is sulfate, sulfonate, carboxylate, borate, boronate, a substituted or unsubstituted phosphate, or a phosphonate,

or the pharmaceutically-acceptable salt thereof.

17. The adhesive of claim 1 , wherein the crosslinking group comprises an actinically crosslinkable group.

18. The adhesive of claim 1 , wherein the monomer comprises two or more olefinic groups.

19. The adhesive of claim 1 , wherein the filler comprises a metal oxide, a ceramic particle, or a water insoluble inorganic salt.

20. The adhesive of claim 1 , wherein the filler comprises nanosilica, microsilica, hydroxyapatite or substituted hydroxyapatite, a nano calcium phosphate particle, alpha-tricalcium phosphate, beta-tricalcium phosphate, amorphous-tricalcium phosphate, or any combination thereof.

21. The adhesive of claim 1 , wherein the water-insoluble filler comprises is functionalized with or more functional groups that react with a crosslinkable group on the polycation, the polyanion, or a combination thereof.

22. The adhesive of claim 1 , wherein the polymerization initiator comprises (1) one or more of a free radical initiator, a thermal initiator, or a photoinitiator, or (2) two or more radical initiators, thermal initiators, or a photoinitiators.

23. The adhesive of claim 1 , wherein the photoinitiator comprises a water-soluble initiator comprising riboflavin, eosin, eosin y, or rose Bengal.

24. The adhesive of claim 1 , wherein the adhesive further comprises one or more contrast agents.

25. The adhesive of claim 1 , wherein the crosslinking step (b) comprises exposing the simple adhesive coacervate to UV irradiation, visible light irradiation, ionizing radiation, or microwave irradiation.

26. The adhesive of claim 25 , wherein the ionizing radiation comprises gamma rays or X-rays.

27. The substrate of claim 10 , wherein the substrate comprises a metal substrate, a foil, a fiber, a tape, a piece of cloth, a device that can be implanted in a subject, or an aquatic substrate comprising coral, a marker, a beacon, an ordinance, or a material for producing an artificial reef.