Tissue-adhesive materials
A multi-lamellar tissue-adhesive sheet comprises a structural layer or laminate conjoined to a tissue-contacting layer. The structural layer or laminate comprises one or more synthetic polymers having film-forming properties, and the tissue-contacting layer of material contains tissue-reactive groups. The synthetic polymers having film-forming properties are preferably biodegradable polyesters, and the tissue-reactive groups are most preferably NHS-ester groups.
1. A multi-lamellar tissue-adhesive sheet comprising a structural layer or laminate, which structural layer or laminate comprises one or more synthetic polymers having film-forming properties, and to which structural layer or laminate is conjoined a tissue-contacting layer comprising poly(VP-AAc-AAc(NHS)) terpolymer.
2. A sheet as claimed in claim 1 , which comprises a structural laminate comprising two or more discrete layers that are conjoined together.
3. A sheet as claimed in claim 2 , wherein the laminate comprises alternating layers of polymer having film-forming properties and material containing reactive functional groups.
4. A sheet as claimed in claim 3 , which comprises a structural laminate comprising two layers of film-forming polymer with a layer of reactive material interposed therebetween, and the tissue-contacting layer.
5. A sheet as claimed in claim 4 , wherein the reactive material is the same as the material of the tissue-contacting layer.
6. A sheet as claimed in claim 1 , wherein the one or more polymers having film-forming properties are polyesters.
7. A sheet as claimed in claim 6 , wherein the polyesters are selected from the group consisting of polylactic acid, polyglycolic acid, polycaprolactones, polyhydroxyalkanoates, and copolymers and blends of any thereof.
8. A sheet as claimed in claim 7 , wherein the polyesters are selected from the group consisting of polylactic acid, polyglycolic acid, and copolymers and blends thereof.
9. A sheet as claimed in claim 8 , wherein the polyester is poly(lactide-co-glycolide).
10. A sheet as claimed in claim 1 , which has an overall thickness of from 0.01 to 1 mm.
11. A sheet as claimed in claim 1 , which has an overall thickness of from 0.015 to 0.05 mm.
12. A sheet as claimed in claim 1 , wherein the tissue-contacting layer accounts for more than 50% of the overall thickness of the sheet.
13. A sheet as claimed in claim 1 , which comprises a structural laminate, which laminate comprises n layers of a film-forming polymer with n−1 layers of material containing reactive functional groups interspersed therebetween, and a tissue-contacting layer of tissue-reactive material, wherein n has a value of 1, 2 or 3.
14. A sheet as claimed in claim 13 , wherein the film-forming polymer is a biodegradable polyester.
15. A sheet as claimed in claim 1 , which comprises a structural laminate, which laminate comprises n layers of a biodegradable polyester with n−1 layers of material containing reactive functional groups interspersed therebetween, and a tissue-contacting layer comprising poly(VP-AAc-AAc(NHS)) terpolymer, wherein n has a value of 1, 2 or 3.
16. A sheet as claimed in claim 14 , wherein the polyester is selected from the group consisting of polylactic acid, polyglycolic acid, polycaprolactones, polyhydroxyalkanoates, and copolymers and blends of any thereof.
17. A sheet as claimed in claim 16 , wherein the polyester is selected from the group consisting of polylactic acid, polyglycolic acid, and copolymers and blends thereof.
18. A sheet as claimed in claim 17 , wherein the polyester is poly(lactide-co-glycolide).
19. A sheet as claimed in claim 13 , wherein the material containing reactive functional groups is poly(VP-AAc-AAc(NHS)).
20. A sheet as claimed in claim 13 , wherein n has a value of 2.
21. A sheet as claimed in claim 20 , wherein the tissue-contacting layer accounts for more than 50% of the overall thickness of the sheet.
22. A sheet as claimed in claim 21 , wherein the tissue-contacting layer accounts for more than 60% of the overall thickness of the sheet.
23. A method of manufacturing a sheet as claimed in claim 1 , which method comprises stepwise formation of the layer(s) of the structural layer or laminate, followed by formation of the tissue-contacting layer.
24. A method of joining a tissue surface to another tissue, or of sealing a tissue surface, which method comprises applying to the tissue surface a sheet as claimed in claim 1 .