Biocompatability of solid surfaces

• US 5,702,818 A
• Filed: 04/27/1995
• Issued: 12/30/1997
• Est. Priority Date: 01/19/1993
• Status: Expired due to Fees

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Cahalan, Linda, Cahalan, Patrick T., Hendriks, Marc, Verhoeven, Michel
• Primary Examiner(s): Tsang, Cecilia J.
• Assistant Examiner(s): DELANEY, PATRICK R
• Application Number:
  US08/430,001
• Time in Patent Office: 978 Days
• Field of Search: 428/409, 428/411.1, 428/425.5, 428/473.5, 428/525, 435/180, 435/181
• US Class Current: 428/409
• CPC Class Codes: A61L 33/0005 Use of materials characterised by their function or physical properties
• CPC Class Codes: A61L 33/0029 using an intermediate layer of polymer
• CPC Class Codes: A61L 33/0041 characterised by the choice of an antithrombatic agent other than heparin heparinoïd A61L33/08; polypeptides A61L33/12
• CPC Class Codes: A61L 33/0088 by grafting of a monomer onto the substrate
• CPC Class Codes: C08L 33/26 Homopolymers or copolymers of acrylamide or methacrylamide
• CPC Class Codes: C08L 79/02 Polyamines
• CPC Class Codes: Y10T 428/31 Surface property or characteristic of web, sheet or block
• CPC Class Codes: Y10T 428/31504 Composite [nonstructural laminate]
• CPC Class Codes: Y10T 428/31562 Next to polyamide [nylon, etc.]
• CPC Class Codes: Y10T 428/31721 Of polyimide
• CPC Class Codes: Y10T 428/31946 Next to second aldehyde or ketone condensation product

Abstract

An improved spacer material for improving the biocompatibility of a biomaterial and a method for making it in which a polyalkylimine is covalently attached to an aminated substrate and combined with a crosslinking agent which is at least difunctional in aldehyde groups. The polyalkylimine can be for example, polyethyleneimine and the crosslinking agent can be, for example, glutaraldehyde. Preferably, the crosslinking agent is applied in dilute solution and at a pH suitable to accomplish light crosslinking of the polyalkylimine and also provide aldehyde linkages at the interface between the biomolecule and the spacer.

Claims

1. A medical device having a biocompatible surface comprising:

(a) a solid surface;

(b) a first layer comprising a graft polymer of acrylamide covalently attached to the solid surface, said graft polymer including carboxylic acid groups pendant to acrylamide moieties of the graft polymer;

(c) a second layer comprising a crosslinked polyalkylimine covalently bonded to the first layer by attachment to the pendant carboxylic acid groups of the first layer; and

(d) a biomolecule covalently bonded to the second layer.

2. A medical device according to claim 1 wherein the covalent attachment between first layer and second layer includes a linking molecule covalently bonded at a first end to a carboxylic acid group of the first layer and covalently bonded to the second layer.

3. A medical device according to claim 2 wherein the linking molecule is a carbodiimde.

4. A medical device according to claim 1 wherein the polyalkylimine is polyethyleneimine.

5. A medical device according to claim 1 wherein the polyalkylimine is crosslinked by a crosslinking agent which is at least difunctional in aldehyde groups.

6. A medical device according to claim 1 wherein the biomolecule is a cellular adhesive molecule.

7. A medical device according to claim 1 wherein the biocompatible surface is the biocompatable surface of a blood oxygenator.

8. A medical device according to claim 1 wherein the biocompatable surface is the biocompatible surface of a catheter.

9. A medical device according to claim 1 wherein the biocompatable surface is the biocompatible surface of a vascular graft.