Polymer composition and dialysis membrane formed from the polymer composition
A biocompatible polymer composition suited to forming a dialysis membrane includes a matrix material and at least one xanthone. The composition may be formed into a membrane for inserting into a dialyzer filter whereby free radicals in the fluid are removed by the membrane.
1. A dialyzer filter unit comprising a semi-permiable membrane housed within the dialyzer filter unit, the semi-permiable membrane comprising:
a matrix material; and
at least one xanthone at least partially dispersed in the matrix material.
2. The dialyzer filter unit of claim 1 , wherein the matrix material is selected from the group consisting of polyamides, polyvinylpyrrolidones, polycarbonates, polysulfones, polyacrylonitriles, and combinations thereof.
3. The dialyzer filter unit of claim 2 , wherein the matrix material comprises a polysulfone, the polysulfone comprising a polyethersulfone.
4. The dialyzer filter unit of claim 1 , wherein the matrix material comprises a blend comprising a polyvinylpyrrolidone and at least one of a polyamide and a polyethersulfone.
5. The dialyzer filter unit of claim 4 , wherein the at least one of a polyamide and a polyethersulfone constitutes at least 5% by weight of the blend.
6. The dialyzer filter unit of claim 1 , wherein the composition is a solid at room temperature.
7. The dialyzer filter unit of claim 1 , wherein the xanthone is hydroxylated.
8. The dialyzer filter unit of claim 1 , wherein the xanthone has a structure represented by Structure 11:
where R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 are independently selected from H, OH and glycosyl and at least one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 and R 8 is OH.
9. The dialyzer filter unit of claim 1 , wherein the xanthone comprises a glycosylated xanthone.
10. The dialyzer filter unit of claim 9 , wherein the glycosylated xanthone comprises 1,3,6,7-tetrahydroxyxanthone-C2-β-D-glycoside (mangiferin).
11. The dialyzer filter unit of claim 1 , wherein the xanthone comprises a non-glycosylated xanthone selected from the group consisting of 1,3,6,7-tetrahydroxyxanthone, 1,3-dihydroxyxanthone, 1,6-dihydroxyxanthone, 1,3,7-trihydroxyxanthone, 1,3,5,6-tetrahydroxyxanthone, 2,3,6,7-tetrahydroxyxanthone, 3,4,5,6-tetrahydroxyxanthone, and combinations thereof.
12. The dialyzer filter unit of claim 1 , wherein the xanthone constitutes at least 1% by weight of the polymer composition.
13. The dialyzer filter unit of claim 1 , wherein the xanthone is dispersed throughout the matrix material.
14. The dialyzer filter unit of claim 1 , wherein the membrane is in the form of at least one of a thin film and fibers.
15. The dialyzer filter unit of claim 1 , wherein the membrane comprises a bundle of hollow fibers.
16. A method of forming a dialyzer filter comprising:
forming a membrane comprising a matrix material; and
at least one xanthone at least partially dispersed in the matrix material; and
inserting the membrane into a housing of a dialyzer filter.
17. A method of removing free radicals from a fluid comprising:
filtering a fluid with the dialyzer filter of claim 1 , whereby free radicals in the fluid are removed by the membrane.
18. A method for hemodialysis or hemofiltration comprising contacting blood with a dialyzer filter of claim 1 .
19. The method of claim 16 , where the method of forming the membrane includes forming the biocompatible polymer composition of claim 1 , comprising the step of:
combining a matrix material for forming a polymer matrix and at least one xanthone to form a mixture.
20. The method of claim 19 , wherein combining the matrix material and at least one xanthone is carried out in the presence of a solvent.
21. The method of claim 20 , wherein the solvent includes at least one of dimethylsulfoxide, dimethylacetamide, and dimethylformamide.
22. The method of claim 20 , wherein the combining includes combining the matrix material, xanthone, and solvent to form a liquid blend.
23. The method of claim 22 , wherein the matrix material and xanthone together constitute at least 1% by weight of the liquid blend.
24. The method of claim 22 , wherein the method further comprises immersing the liquid blend into a non-solvent to solidify the biocompatible polymer.
25. The method of claim 22 , wherein the method further includes forming fibers from the liquid blend.
26. A dialyzer filter unit comprising a semi-permiable membrane
housed within the the dialyzer filter unit, the semi-permiable membrane comprising:
a matrix material; and
at least one anti-oxidant which is held within the matrix material by hydrogen bonding and wherein the anti-oxidant comprises a xanthone.
27. The dialyzer filter unit of claim 1 , wherein at least one xanthone is defined by the by Structure 11:
where R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 are independently selected from H and OH and at least one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 and R 8 is OH.