SUPER-SPARGER MICROCARRIER BEADS AND PRECISION EXTRUSION DEPOSITED POLY-EPSILON-CAPROLACTONE STRUCTURES FOR BIOLOGICAL APPLICATIONS

• US 20080020049A1
• Filed: 08/21/2007
• Published: 01/24/2008
• Est. Priority Date: 02/25/2005
• Status: Abandoned Application

• Current Assignee: Andrew Darling, Lauren Shor, Selcuk Guceri, Wei Sun
• Original Assignee: Andrew Darling, Lauren Shor, Selcuk Guceri, Wei Sun
• Inventors: Guceri, Selcuk, Sun, Wei, Darling, Andrew, Shor, Lauren
• Application Number:
  US11/842,796
• Publication Number:
  US 20080020049A1
• Time in Patent Office: Days
• US Class Current: 424/489
• CPC Class Codes: A61L 27/38 containing added animal cells organs or tissue containing native cells A61L27/36
• CPC Class Codes: A61L 27/46 with phosphorus-containing inorganic fillers
• CPC Class Codes: A61L 27/48 with macromolecular fillers
• CPC Class Codes: A61L 27/56 Porous materials, e.g. foams or sponges
• CPC Class Codes: B29C 48/07 Flat, e.g. panels
• CPC Class Codes: B29C 48/11 comprising two or more partially or fully enclosed cavities, e.g. honeycomb-shaped
• CPC Class Codes: B29C 48/12 Articles with an irregular circumference when viewed in cross-section, e.g. window profiles
• CPC Class Codes: C12N 11/02 Enzymes or microbial cells immobilised on or in an organic carrier
• CPC Class Codes: C12N 2533/18 Calcium salts, e.g. apatite, Mineral components from bones, teeth, shells
• CPC Class Codes: C12N 2533/40 Polyhydroxyacids, e.g. polymers of glycolic or lactic acid (PGA, PLA, PLGA); Bioresorbable polymers
• CPC Class Codes: C12N 2533/54 Collagen; Gelatin
• CPC Class Codes: C12N 2533/56 Fibrin; Thrombin
• CPC Class Codes: C12N 2533/74 Alginate
• CPC Class Codes: C12N 5/0075 using microcarriers

Abstract

In on aspect, the invention includes a microcarrier bead having a porous three-dimensional core having (a) a polymeric porous three-dimensional body having porosity of about 15 to about 90% such that at least 99% of pores are interconnected and have diameters of at most 200 microns, (b) an outer protective layer and optionally (c) a filler. In another aspect, the invention includes a method of making an artificial scaffold wherein a scaffolding material is extruded into a coolant and thereby creating a porous material having a porosity of between 15-90% such that at least 99% of pores are interconnected and have diameters of at most 200 microns.

Claims

1. A microcarrier bead comprising a porous three-dimensional core having (a) a polymeric porous three-dimensional body having porosity of about 15 to about 90% such that at least 99% of pores are interconnected and have diameters of at most 200 microns, (b) an outer protective layer and optionally (c) a filler material in communication with the polymeric porous three-dimensional core.

3. The microcarrier bead of claim 1, wherein the porous three-dimensional core is made from a scaffold material comprising at least one of a biodegradable polymer, fibrin, collagen, and mixtures thereof.

4. The microcarrier bead of claim 3, wherein the scaffolding material further comprises hydroxyapatite.

5. The microcarrier bead of claim 3, wherein the scaffold material is at least one of poly-caprolactone, polylactic acid, polyglycolic acid, and poly(lactide co-glycolide).

6. The microcarrier bead of claim 1, wherein the filler material is at least one of fibrin, collagen, and dextran.

7. The microcarrier bead of claim 1, wherein the outer protective layer comprises hydrogel.

8. The microcarrier bead of claim 3, wherein the scaffold material comprises a biodegradable polyester and the outer protective layer comprises alginate.

9. The microcarrier bead of claim 1, wherein the porous three-dimensional core is made by depositing poly-caprolactone in a layered pattern such that at least 99% of pores is interconnected and at least 99% of pores lead to the external surface of the microcarrier bead.

10. The microcarrier bead of claim 1, further comprising cells.

25. A method of growing cells, the method comprising:

providing the microcarrier bead of claim 1;

providing cells within the microcarrier bead; and

providing a bioreactor having an agitation rate and a sparging rate beyond the shear limit of cells in suspension.

2. (canceled)

11. A method for making an artificial scaffold having porosity of about 15 to about 90% such that at least 99% of pores are interconnected and have diameters of at most 200 microns, the method comprising:

providing a scaffolding material;

providing a coolant having a thermal conductivity of greater than 0.026; and

extruding the scaffolding material into the coolant and thereby making the artificial scaffold having a porous three-dimensional body wherein at least 99% of pores in the porous three-dimensional body are interconnected and lead to an external surface of the porous three-dimensional body and wherein pores have diameters of at most 200 microns.

12. The method of claim 11, wherein extruding the scaffolding material into the coolant is performed in a layered pattern such that each subsequently extruded layer of the scaffolding material is deposited on top of a previously extruded layer of the scaffolding material.

13. The method of claim 11, wherein the scaffolding material comprises at least one of a biodegradable polymer, fibrin, collagen, and mixtures thereof.

14. The method of claim 13, wherein the scaffolding material further comprises hydroxyapatite.

15. The method of claim 11, wherein the coolant is at least one of a liquid, a foam, and a hydrogel.

16. The method of claim 11, wherein at least one of the scaffolding material or the coolant comprises a biomaterial.

17. The method of claim 11, wherein the coolant has a temperature at least 5°

C. lower than the scaffolding material.

18. The method of claim 11, further comprising providing a filler to the porous three-dimensional body.

19. The method of claim 11, further comprising providing cells to the porous three-dimensional body.

20. The method of claim 18, further comprising providing cells to the porous three-dimensional body.

21. The method of claim 19, further comprising encapsulating the porous three-dimensional body with an outer protective layer.

22. The method of claim 20, further comprising encapsulating the porous three-dimensional body with an outer protective layer.

23. An artificial tissue comprising a scaffold having a polymeric porous three-dimensional body having porosity of about 15 to about 90% such that at least 99% of pores are interconnected and have diameters of at most 200 microns and optionally, cells.

24. In a process for manufacturing an artificial scaffold comprising (a) utilizing a computer aided design program to design the artificial scaffold;

(b) converting the computer aided design program designed artificial scaffold into a heterogeneous material and multi-part assembly model which can be used for multi-nozzle printing; and

(c) printing the designed artificial scaffold using different nozzles, the improvement comprising extruding a scaffolding material into a coolant having a thermal conductivity greater than 0.026, wherein the coolant has a temperature at least 5°

C. lower than the scaffolding material and thereby making the artificial scaffold having porosity of about 15 to about 88% such that at least 99% of pores are interconnected and have diameters of at most 100 microns and optionally an outer protective layer encapsulating the artificial scaffold.