Mineralization and Biological Modification of Biomaterial Surfaces

• US 20090226602A1
• Filed: 04/30/2009
• Published: 09/10/2009
• Est. Priority Date: 03/19/1999
• Status: Active Grant

• Current Assignee: Board of Regents of the University of Michigan (University of Michigan)
• Original Assignee: Board of Regents of the University of Michigan (University of Michigan)
• Inventors: Murphy, William L., Mooney, David J., Peters, Martin C., Kohn, David H.
• Granted Patent: US 9,072,813 B2
• Time in Patent Office: Days
• US Class Current: 427/2.260
• CPC Class Codes: A61L 2400/18 Modification of implant surfaces in order to improve biocompatibility, cell growth, fixation of biomolecules, e.g. plasma treatment
• CPC Class Codes: A61L 2430/02 for reconstruction of bones; weight-bearing implants
• CPC Class Codes: A61L 27/00 Materials for grafts or prostheses or for coating grafts or prostheses dental prostheses A61C13/00; shape or structure of prostheses A61F2/00; use of preparations for artificial teeth A61K6/80; artificial kidneys A61M1/14
• CPC Class Codes: A61L 27/18 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61L 27/306 Other specific inorganic materials not covered by A61L27/303 - A61L27/32
• CPC Class Codes: A61L 27/44 having a macromolecular matrix
• CPC Class Codes: A61L 27/50 Materials characterised by their function or physical properties , e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
• CPC Class Codes: A61L 27/56 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 27/58 Materials at least partially resorbable by the body
• CPC Class Codes: C08L 67/04 Polyesters derived from hydroxycarboxylic acids, e.g. lactones C08L67/06 takes precedence

Abstract

Disclosed are advantageous methods for patterning and/or mineralizing biomaterial surfaces. The techniques described are particularly useful for generating three-dimensional or contoured bioimplant materials with patterned surfaces or patterned, mineralized surfaces. Also provided are various methods of using the mineralized and/or patterned biomaterials in tissue engineering, such as bone tissue engineering, providing more control over ongoing biological processes, such as mineralization, growth factor release, cellular attachment and tissue growth.

Claims

1. A method for controlling mineralization of a biomaterial surface, comprising functionalizing at least a first surface of a biomaterial and contacting the functionalized biomaterial surface with an amount of a mineral-containing solution effective to form a mineralized biomaterial that comprises an extended, mineral coating at the functionalized biomaterial surface;

said biomaterial comprising at least a first porous, biodegradable polymer portion that has an interconnected pore structure and that is degradable over a controllable time scale, said biomaterial further comprising at least a first portion that is prepared by a process comprising heating a biodegradable polymer

2. The method of claim 1 wherein heating the biodegradable polymer in a heat pressing process.

3. The method of claim 1 wherein the polymer portion of the biomaterial is a poly(alpha-hydroxy acid).

4. The method of claim 1 wherein the functionalizing step creates a plurality of polar oxygen groups on the biomaterial surface.

5. The method of claim 1 wherein said mineral coating is osteoconductive.

6. The method of claim 1 wherein the biomaterial is associated with a biologically effective amount of at least a first bioactive substance or biological cell.

7. A method for controlling mineralization of a biomaterial surface, said process comprising the steps of:

a) forming a biomaterial by heating a biodegradable polymer, said biomaterial comprising at least a first porous, biodegradable polymer portion that has an interconnected pore structure.

b) functionalizing a first surface of said biomaterial,

c) contacting the functionalized biomaterial surface with an amount of a mineral-containing solution effective to form a mineralized biomaterial that comprises an extended, mineral coating at the functionalized biomaterial surface.

8. The method of claim 7 wherein the forming step is heat pressing.

9. The method of claim 7 wherein said biodegradable polymer is a poly(alpha-hydroxy) acid.

10. The method of claim 7 wherein the functionalizing step creates a plurality of polar oxygen groups on the biomaterial surface.

11. The method of claim 7 wherein said mineral coating is osteoconductive.

12. The method of claim 7 wherein the biomaterial is associated with a biologically effective amount of at least a first bioactive substance or biological cell.

13. A method for generating an extended, osteoconductive mineral coating on a surface of a porous, biodegradable polymer biomaterial, comprising contacting a surface of said porous, biodegradable polymer biomaterial with an amount of a mineral-containing solution effective to form an extended, osteoconductive mineral coating on said surface;

wherein said porous, biodegradable polymer biomaterial has an interconnected pore structure and is degradable over a controllable time scale and wherein said biomaterial comprises at least a first portion that is prepared by a process comprising heating a biodegradable polymer.

14. The method of claim 13 wherein heating is heat pressing.

15. The method of claim 13 wherein the biodegradable polymer is poly(alpha-hydroxy acid).

16. The method of claim 13 further comprising exposing at least a first surface of said biomaterial to a functionalizing pre-treatment to create a functionalized biomaterial surface prior to contacting the biomaterial surface with an amount of a mineral-containing solution

17. The method of claim 16, wherein the functionalized biomaterial surface is contacted with said mineral-containing solution for a time effective to form discrete mineral islands that expand to form a substantially homogeneous, osteoconductive mineral coating.

18. The method of claim 13 wherein the biomaterial surface is part of a 3-dimensional biomaterial scaffold.

19. The method of claim 13 wherein the biomaterial is associated with a biologically effective amount of at least a first bioactive substance or biological cell.

20. The method of claim 16 wherein said biodegradable polymer biomaterial is a poly(alpha-hydroxy) acid.