Patent ID: 6896926

Claim:
A method for applying a biocompatible layer-by-layer coating onto a medical device, comprising the steps of: (a) contacting said medical device with a first coating solution containing a first polyionic material to non-covalently apply an innermost layer of the first polyionic material onto said medical device, and wherein prior to contacting with the first coating solution said medical device is not subjected to a surface modification; (b) contacting said medical device having the innermost layer of the first polyionic material with a second ccating solution containing a second polyionic material, to form a first polyelectrolyte bilayer consisting of the innermost layer of the first polyionic material and one layer of the second polyionic material on top of the innermost layer, wherein the second polyionic material has charges opposite of the charges of the first polyionic material; (c) contacting said medical device having the first polyelectrolyte bilayer with a third coating solution containing the first polyionic material or a third polyionic material, to form a layer of the first polyionic material or the third polyionic material on top of the first polyelectrolyte poilayer, wherein the third polyionic material has charges opposite of the charges of the second polyionic material; (d) contacting said medical device having the first polyelectrolyte bilayer and one layer of the first polyionic material or the third polyionic material on top of the first polyelectrolyte bilayer with a fourth coating solution containing the second polyionic material or a fourth polyionic material having charges opposite of the charges of the first or third polyionic material, to form a second pelyelectrolyte bilayer consisting of the layer of the first polyionic material or the third polyionic material and one layer of the second material; and, optionally, (e) repeating steps (c) and (d) for a number of times to build up additional polyelectrolyte bilayers until formation of the layer by layer coating on the medical device, wherein the concentration of the first polyionic material in said first coating solution is selected to be at least ten times higher than the concentration of any polyionic material in any coating solution other than the first coating solution so as to impart to the layer-by-layer coating a relatively high hydrophilicity characterized by an averaged contact angle of less than about 54 degrees.