Electrochemical attachment of phosphonic acids to metallic substrates and osteoconductive medical devices containing same

1. A method comprising:

preparing a solution of a phosphorous-based acid in a solvent, wherein the phosphorus-based acid is a phosphonic acid having the formula (OH) 2 P(O)(RX),

wherein R is an alky group having between four and twenty-five carbon atoms, and X is selected from the group consisting of a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted amine group, and a substituted or unsubstituted ester group;

immersing at least a portion of a metal work piece into the solution of the phosphorous-based acid;

immersing at least a portion a reference metal into the solution of the phosphorous-based acid;

supplying a voltage for a duration of time, wherein the at least portion of the metal work piece comprises an anode and the at least portion of the reference metal comprises a cathode during the supplying of the voltage;

removing the metal work piece from the solution of the phosphorous-based acid;

cleaning the metal work piece; and

drying the cleaned metal work piece to obtain a surface modified metal work piece.

2. The method according to claim 1 , wherein X is a substituted or unsubstituted methacrylate group.

3. The method of claim 1 , wherein the phosphonic acid is selected from the group consisting of octadecylphosphonic acid, decylphosphonic acid, and dodecylphosphonic acid.

4. The method according to claim 1 , wherein the metal work piece is a non-ferrous metal.

5. The method according to claim 4 , wherein the metal work piece is selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Al and alloys thereof.

6. The method according to claim 5 , wherein the metal work piece is selected from the group consisting of titanium, titanium alloys, aluminum and aluminum alloys.

7. The method according to claim 1 , wherein the metal work piece is stainless steel.

8. The method according to claim 1 , wherein the solvent is selected from the group consisting of n-butanol, isopropanol, ethanol, methanol, formic acid, acetic acid, tetrahydrofuran (THF), dimethylformamide (DMF), and ionic liquids.

9. The method according to claim 1 , wherein the concentration of the phosphorus-based acid in the solution is from about 1% to about 10% by weight.

10. The method according to claim 1 , wherein the voltage range is from about 1 V to about 300 V.

11. The method according to claim 10 , wherein the voltage range is from about 1 V to about 100 V.

12. The method according to claim 1 , wherein the duration of time is from about 1 second to about 5 minutes.

13. The method according to claim 1 , wherein drying the cleaned metal work piece is carried out in an inert atmosphere or dry air.

14. The method according to claim 1 , wherein a coefficient of friction of the surface modified metal work piece is up to 99% lower than a coefficient of friction of an untreated metal surface.

15. The method according to claim 14 , wherein the coefficient of friction of the surface modified metal work piece is about 34% to about 59% lower than a coefficient of friction of an untreated metal surface.

16. The method according to claim 1 , wherein a static coefficient of friction of the surface modified metal work piece is up to 99% lower than a static coefficient of friction of an untreated metal surface.

17. The method according to claim 16 , wherein the static coefficient of friction of the surface modified metal work piece is about 34% to about 46% lower than a static coefficient of friction of an untreated metal surface.

18. The method according to claim 1 , wherein a dynamic coefficient of friction of the surface modified metal work piece is up to 99% lower than a dynamic coefficient of friction of an untreated metal surface.

19. The method according to claim 18 , wherein the dynamic coefficient of friction of the surface modified metal work piece is about 50% to about 59% lower than a dynamic coefficient of friction of an untreated metal surface.