DEVICES WITH MULTIPLE SURFACE FUNCTIONALITY
Phosphorus-based coatings having a plurality of phosphate moieties, a plurality of phosphonate moieties, or both, covalently bonded to an oxide surface of an implantable substrate exhibiting one or more of the following characteristics: (a) the surface phosphorus-containing group density of the coated regions of the substrate is at least about 0.1 nmol/cm 2 ; (b) the phosphorus-based coating has a thickness of less than about 10 nm; or (c) the surface phosphorus-containing group density of the coated regions of the substrate is equal to or greater than the surface hydroxyl group density of the oxide surface of the substrate. Implantable devices embodying the coated substrates are also disclosed.
1 . A phosphorus-based coating comprising a plurality of organophosphonate moieties which are covalently bonded to a native oxide surface of an implantable medical device, wherein:
(a) the surface phosphorus-containing group density of the coated regions of said device is in the range of about 0.5 nmol/cm 2 to about 1.5 nmol/cm 2 ;
(b) the phosphorus-based coating has a thickness of less than about 2 nm; and
(c) the phosphorus-based coating comprises a surface phosphorus-containing group density of at least about 2 times the surface hydroxyl group density of the oxide surface of the implantable device;
wherein said native oxide surface comprises a metal surface selected from the group consisting of titanium, titanium alloys, stainless steel, stainless steel alloys, tantalum, silicon, cobalt-chromium and cobalt-chromium alloys.
2 . The phosphorus-based coating of claim 1 , wherein said phosphorus-based coating is cell resistant.
3 . An implantable device comprising the phosphorus-based coating of claim 1 , wherein the phosphorus-based coating is bound to the oxide surface of the implant to attain a shear strength of at least about 20 MPa.
4 . An implantable device comprising the phosphorus-based coating of claim 1 , wherein the phosphorus-based coating is bound to the oxide surface of the implant to attain a shear strength of at least about 40 MPa.
5 . An implantable device comprising the phosphorus-based coating of claim 1 , wherein the phosphorus-based coating is bound to the oxide surface of the implant to attain a shear strength of at least about 50 MPa.
6 . An implantable device comprising the phosphorus-based coating of claim 1 , wherein the phosphorus-based coating is bound to the oxide surface of the implant to attain a tensile strength of at least about 60 MPa.
7 . An implantable device comprising the phosphorus-based coating of claim 1 , wherein the phosphorus-based coating is bound to the oxide surface of the device to attain a tensile strength of at least about 80 MPa.
8 . The phosphorus-based coating of claim 1 , wherein the outer surface of the coating exhibits functional groups at positions remote to the organophosphonate moieties, said functional groups comprising hydroxyl groups, phosphonate groups, phosphate groups, amino groups, thiol groups, carboxylate groups or a combination or a derivative thereof.
9 . An implantable device comprising the phosphorus-based coating of claim 1 , selected from the group consisting of vascular devices, artificial hearts, heart assist devices, orthopedic devices, dental devices, drug delivery devices, ophthalmic devices, urological devices, catheters, neurological devices, neurostimulation devices, electrostimulation devices, electrosensing devices and synthetic prostheses.
10 . The implantable device of claim 9 , wherein the vascular device is selected from the group consisting of grafts, stents, stent grafts, catheters, valves, artificial hearts and pacemakers.
11 . The implantable device of claim 9 , wherein the orthopedic device is selected from the group consisting of a fracture repair device and artificial tendon.
12 . The implantable device of claim 9 , wherein the ophthalmic device is a glaucoma drain shunt.
13 . The implantable device of claim 9 , wherein the urological device is selected from the group consisting of penile devices, sphincter devices, urethral devices, bladder devices and renal devices.
14 . The implantable device of claim 9 , wherein the synthetic prosthesis is selected from the group consisting of breast prostheses and artificial organs.
15 . The implantable device of claim 9 , wherein the device is selected from the group consisting of dialysis tubing and membranes, blood oxygenator tubing and membranes, blood bags, sutures, membranes, cell culture devices, chromatographic support materials, biosensors, anastomotic connectors, surgical instruments, angioplasty balloons, wound drains, shunts, tubing, urethral inserts, blood oxygenator pumps, and wound tubing.
16 . The implantable device of claim 9 , wherein the device is selected from the group consisting of electrical stimulation leads, brain tissue stimulators, central nerve stimulators, peripheral nerve stimulators, spinal cord nerve stimulators and sacral nerve stimulators.
17 . An implantable device comprising the phosphorus-based coating of claim 1 , wherein the substrate is a metallic substrate.
18 . The implantable device of claim 17 , wherein the substrate is titanium or an alloy thereof.