Methods for improving the bioactivity characteristics of a surface and objects with surfaces improved thereby

1. A method of improving bioactivity of a surface of an implantable object, the method comprising:

forming an accelerated neutral beam in a reduced-pressure chamber including

forming a gas-cluster ion-beam comprising ionized gas clusters in a reduced-pressure chamber,

accelerating the gas-cluster ion-beam along a beam path,

at least partially dissociating gas-clusters in the gas-cluster ion-beam along the beam path by increasing the range of velocities of ions in the accelerated gas cluster ion beam,

at least partially neutralizing the gas-cluster ion-beam, and

separating ionized particles from the at least partiallly neutralized gas-cluster ion-beam to form the accelerated neutral beam wherein the neutral beam is essentially free of intermediate size clusters;

introducing an object into the beam path in the reduced-pressure chamber;

wherein said object is selected from the group consisting of a medical prosthesis, a surgical implant, a surgical graft, a component of a medical prosthesis, a component of a surgical implant, a component of a surgical graft, and other objects intended for implantation in a living mammal; and

irradiating at least a first portion of the surface of said object with the accelerated neutral beam.

2. The method of claims 1 , wherein the separating step comprises use of electrostatic separating means.

3. The method of claims 1 , wherein the at least a portion of the surface or object comprises polyether ether ketone (PEEK).

4. The method of claims 1 , wherein the neutral beam is essentially a monomer beam.

5. The method of claims 1 , wherein the neutral beam comprises neutral gas clusters.

6. A method of inducing cell growth on or adjacent to an object, the method comprising:

selecting at least a portion of a surface of an object, wherein said portion comprises polyether ether ketone (PEEK);

forming an accelerated neutral beam in a reduced-pressure chamber by forming a gas-cluster ion-beam, accelerating the gas-cluster ion-beam along a beam path, at least partially dissociating gas-clusters in the gas-cluster ion-beam along the beam path by increasing the range of velocities of ions in the accelerated gas cluster ion beam, at least partially neutralized the gas-cluster ion-beam, and separating ionized particles from the at least partially neutralized gas-cluster ion-beam to form the accelerated neutral beam along the beam path;

introducing said object into the beam path in said reduced-pressure chamber;

irradiating said at least a portion of said surface with said accelerated neutral beam;

removing said object from said reduced-pressure chamber; and

exposing said at least a portion of said surface to living cells.

7. An article having a surface region comprising polyether ether ketone (PEEK) with attached cells made by a method comprising the steps of:

selecting at least a portion of a surface comprising polyether ether ketone of an object for attaching cells;

forming an accelerated neutral beam in a reduced-pressure chamber by forming a gas-cluster ion-beam, accelerating the gas-cluster ion-beam along a beam path, at least partially dissociating gas-clusters in the gas-cluster ion-beam along the beam path by increasing the range of velocities of ions in the accelerated gas cluster ion beam, at least partially neutralizing the gas-cluster ion-beam, and separating ionized particles from the at least partially neutralized gas-cluster ion-beam to form the accelerated neutral beam along the beam path;

introducing said article into the beam path in said reduced-pressure chamber;

irradiating said at least a portion of said surface with the accelerated neutral beam;

removing said object from said reduced-pressure chamber; and

exposing said at least a portion of said surface to living cells.

8. A method of improving bioactivity of a surface of an object, the method comprising:

forming an accelerated neutral beam in a reduced-pressure chamber by forming a gas-cluster ion-beam, accelerating the gas-cluster ion-beam along a beam path, at least partially dissociating gas-clusters in the gas-cluster ion-beam along the beam path by increasing the range of velocities of ions in the accelerated gas cluster ion beam, at least partially neutralizing the gas-cluster ion-beam, and separating ionized particles from the at least partially neutralized gas-cluster ion-beam to form the accelerated neutral beam along the beam path;

introducing an object into the beam path in the reduced-pressure chamber;

wherein said surface of said object comprises an electrically insulating material; and

irradiating at least a first portion of the surface of said object with the accelerated neutral beam.

9. The method of claim 8 , wherein the at least a first portion of the surface comprises any material of the group consisting of a plastic, a polymer, a glass, a glassy material, polystyrene, polytetrafluoroethylene (PTFE), polyether ether ketone (PEEK), quartz, sapphire, polyethylene terephthalate (PETE) fabric, polyethylene, a solid resin material, a woven polymeric or co-polymeric fabric, a knitted polymeric or co-polymeric fabric, a non-woven polymeric or co-polymeric fabric, bone, collagen, silk, a natural fiber, or a ceramic.

10. The method of claim 9 , wherein the surface of the object comprises an amorphous material.

11. The method of claim 8 , wherein the step of separating ionized particles removes essentially all ionized particles from the beam path.

12. The method of claim 1 , wherein the accelerated neutral beam consists essentially of gas from the gas cluster ion beam.

13. The method of claim 1 , wherein the step of at least partially dissociating includes raising an acceleration voltage in the step of accelerating.

14. The method of claim 1 , wherein the step of at least partially dissociating includes improving ionization efficiency in the forming of the gas cluster ion beam.