Porous polymeric particle comprising polyvinyl alcohol and having interior to surface porosity-gradient

• US 7,842,377 B2
• Filed: 09/23/2008
• Issued: 11/30/2010
• Est. Priority Date: 08/08/2003
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Inventors: Casey, Thomas V. II, Lanphere, Janel, Kapoglis, Greg, St. Pierre, Ernest J.
• Primary Examiner(s): Le; H. (Holly) T
• Application Number:
  US12/236,051
• Publication Number:
  US 20090030117A1
• Time in Patent Office: 798 Days
• Field of Search: 428/402, 428/212, 428/304.4, 428/310.5, 424/489, 424/493, 424/501, 514/951, 514/964
• US Class Current: 428/212
• CPC Class Codes: A61K 49/0452 Solutions, e.g. for injection
• CPC Class Codes: A61K 9/1635 obtained by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polyvinyl pyrrolidone, poly(meth)acrylates
• CPC Class Codes: A61K 9/1652 Polysaccharides, e.g. alginate, cellulose derivatives; Cyclodextrin homeopathic globules A61K9/1623
• CPC Class Codes: A61L 24/0036 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 2430/36 for embolization or occlusion, e.g. vaso-occlusive compositions or devices artificial blood vessels A61L27/507
• CPC Class Codes: A61P 7/00 Drugs for disorders of the blood or the extracellular fluid
• CPC Class Codes: Y10T 428/24942 including components having same physical characteristic in differing degree
• CPC Class Codes: Y10T 428/249953 Composite having voids in a component [e.g., porous, cellular, etc.]
• CPC Class Codes: Y10T 428/249961 With gradual property change within a component
• CPC Class Codes: Y10T 428/2982 Particulate matter [e.g., sphere, flake, etc.]

Abstract

A composition includes a plurality of particles. At least some of the plurality of particles include cross-linked polyvinyl alcohol and have a diameter of about 500 microns or less. The particles have a first average pore size in an interior region, and a second average pore size at a surface region. The first average pore size being greater than the second average pore size. The composition also includes a carrier fluid. The plurality of particles being in the carrier fluid.

Claims

1. A composition, comprising:

a plurality of particles, at least some of the plurality of particles comprising cross-linked polyvinyl alcohol and having a diameter of about 500 microns or less, the at least some of the particles having a first average pore size in an interior region and a second average pore size at a surface region, the first average pore size being greater than the second average pore size; and

a carrier fluid, the plurality of particles being in the carrier fluid.

2. The composition of claim 1, wherein the at least some of the particles have an average diameter of about 10 microns or more.

3. The composition of claim 1, wherein the at least some of the particles have an average diameter of about 100 microns or more.

4. The composition of claim 1, wherein the at least some of the particles have an average diameter of about 300 microns or less.

5. The composition of claim 1, wherein the at least some of the particles have an average diameter of about 300 microns or more.

6. The composition of claim 1, wherein the at least some of the particles are at least partially coated with a substantially bioabsorbable material.

7. The composition of claim 1, wherein the at least some of the particles have a density of from about 1.1 grams per cubic centimeter to about 1.4 grams per cubic centimeter.

8. The composition of claim 1, wherein the at least some of the particles have an average sphericity of about 0.9 or more.

9. The composition of claim 1, wherein, after compression to about 50 percent, the at least some of the particles have an average sphericity of about 0.9 or more.

10. The composition of claim 1, wherein the at least some of the particles comprise about 2.5 weight percent or less polysaccharide.

11. The composition of claim 10, wherein the polysaccharide comprises alginate.

12. The composition of claim 11, wherein the alginate has a guluronic acid content of about 60 percent or greater.

13. The composition of claim 1, wherein the at least some of the particles are substantially insoluble in DMSO.

14. The composition of claim 1, wherein the at least some of the particles are substantially free of animal-derived compounds.

15. The composition of claim 1, wherein the at least some of the particles have a first density of pores in the interior region and a second density of pores at a surface region, and the first density is different from the second density.

16. A composition, comprising:

a plurality of particles, at least some of the plurality of particles comprising polysaccharide and having a diameter of about 500 microns or less, the at least some of the particles having an interior region defining pores and a surface region defining pores, the at least some of the particles having a first density of pores in the interior region and a second density of pores at the surface region, the first density being different from the second density, the at least some of the particles having a first average pore size in the interior region and a second average pore size at the surface region, and the first average pore size being greater than the second average pore size; and

a carrier fluid, the plurality of particles being in the carrier fluid.

17. The composition of claim 16, wherein the at least some of the particles have an average diameter of about 10 microns or more.

18. The composition of claim 16, wherein the at least some of the particles have an average diameter of about 100 microns or more.

19. The composition of claim 18, wherein the at least some of the particles have an average diameter of about 300 microns or less.

20. The composition of claim 16, wherein the at least some of the particles have an average a diameter of about 300 microns or more.

21. The composition of claim 16, wherein the at least some of the particles comprise about 2.5 weight percent or less of the polysaccharide.

22. The composition of claim 21, wherein the polysaccharide comprises alginate.

23. The composition of claim 16, wherein the at least some of the particles further comprise cross-linked polyvinyl alcohol.