Biocompatible surfaces and devices incorporating such surfaces

• US 9,775,933 B2
• Filed: 02/22/2013
• Issued: 10/03/2017
• Est. Priority Date: 03/02/2012
• Status: Active Grant

• Current Assignee: W. L. Gore & Associates (W.L. Gore & Associates)
• Original Assignee: W. L. Gore & Associates (W.L. Gore & Associates)
• Inventors: Knisley, Keith A., Marla, Vishnu T., Radspinner, Rachel, Silvagni, Paul A., Strid, Jason J., Vonesh, Michael J.
• Primary Examiner(s): SCHALL, MATTHEW WAYNE
• Application Number:
  US13/773,937
• Publication Number:
  US 20130231733A1
• Time in Patent Office: 1,684 Days
• Field of Search: 623 139
• CPC Class Codes: A61F 2/0077 Special surfaces of prostheses, e.g. for improving ingrowth A61F2/30767 takes precedence
• CPC Class Codes: A61F 2/82 Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95; for closing wounds, or holding wounds closed A61B17/04 - A61B17/115; dilators A61M29/00
• CPC Class Codes: A61F 2002/009 for hindering or preventing attachment of biological tissue
• CPC Class Codes: A61L 2300/416 Anti-neoplastic or anti-proliferative or anti-restenosis or anti-angiogenic agents, e.g. paclitaxel, sirolimus
• CPC Class Codes: A61L 2300/42 Anti-thrombotic agents, anticoagulants, anti-platelet agents
• CPC Class Codes: A61L 2400/12 Nanosized materials, e.g. nanofibres, nanoparticles, nanowires, nanotubes; Nanostructured surfaces
• 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 31/048 obtained by reactions only involving carbon-to-carbon unsaturated bonds A61L31/041 takes precedence
• CPC Class Codes: A61L 31/06 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds A61L31/041 takes precedence
• CPC Class Codes: A61L 31/10 Macromolecular materials
• CPC Class Codes: A61L 31/146 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 31/16 Biologically active materials, e.g. therapeutic substances A61L31/047 takes precedence
• CPC Class Codes: A61L 33/007 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 33/064 obtained by reactions only involving carbon-to-carbon unsaturated bonds A61L33/062 takes precedence
• CPC Class Codes: C08L 27/12 containing fluorine atoms
• CPC Class Codes: C08L 27/18 Homopolymers or copolymers or tetrafluoroethene

Abstract

The invention is an improved biocompatible surface for a variety of medical purposes. The biocompatible surface employs a unique tight microstructure that demonstrates enhanced cellular response in the body, particularly when placed in contact with blood. As a blood contact surface, the present invention can be beneficially employed in a wide variety of implantable devices and in many other devices and equipment that come in contact with blood.

Claims

1. A blood contact surface comprising

a polytetrafluoroethylene microstructure of nodes and fibrils in both an x direction and in a substantially perpendicular y direction;

wherein the nodes and fibrils have a mean distance between adjacent nodes of 5 micron or less; and

wherein the mean width of the 32 largest nodes in a representative 10,000×

SEM micrograph is less than about 1.5 micron.

2. The blood contact surface of claim 1 wherein the nodes and fibrils have a ratio of mean distances between adjacent nodes in the x and y directions of about 2:

1 to 1.1.

3. The blood contact surface of claim 2 wherein the ratio of mean distances between adjacent nodes in the x and y directions is about 1:

1.

4. The blood contact surface of claim 1 wherein the expanded polytetrafluoroethylene comprises a multi-axially expanded polytetrafluoroethylene.

5. The blood contact surface of claim 4 wherein the expanded polytetrafluoroethylene comprises a bi-axially expanded polytetrafluoroethylene.

6. The blood contact surface of claim 1 wherein the expanded polytetrafluoroethylene comprises fibrils extended outwardly from the nodes in substantially perpendicular directions.

7. The blood contact surface of claim 1 wherein the mean width of the nodes comprises less than about 1.25 micron.

8. The blood contact surface of claim 1 wherein the mean width of the nodes is less than about 1 micron.

9. The blood contact surface of claim 1 wherein the ratio of mean distances between adjacent nodes in the x and y directions is less than 1.5 to 1.

10. The blood contact surface of claim 1 wherein the microstructure substantially prevents cellular in-growth.

11. The blood contact surface of claim 1 wherein the blood contact surface is incorporated in an implantable medical device.

12. The blood contact surface of claim 1 wherein the blood contact surface is incorporated in a non-implantable medical device.

13. The blood contact surface of claim 1 wherein the mean distance between adjacent nodes is less than about 4 micron.

14. The blood contact surface of claim 13 wherein the mean distance between adjacent nodes is less than about 3 micron.

15. The blood contact surface of claim 11 wherein the implantable medical device includes a stent.

16. The blood contact surface of claim 1 wherein endothelial cells attach intimately to the node and fibril microstructure.