# US 2011/0217351 A1 · Coating for medical implants > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2011/0217351 A1 - Document ID: US20110217351A1 - Status: Published application - Kind: A1 - Application number: 12/717,666 - Filed: 2010-03-04 - Published: 2011-09-08 - Earliest claimed: 2010-03-04 - Assignees: Southwest Research Institute - Inventors: Xingguo CHENG; Nitin NITIN; Jorge G. ROSSINI; Stephen T. WELLINGHOFF - Web page: https://patentgrep.com/patent/US20110217351A1 ## CPC - A61F 2/02: Prostheses implantable into the body - A61L 27/34: Macromolecular materials - A61L 27/54: Biologically active materials, e.g. therapeutic substances {(A61L27/227 takes precedence)} - A61L 31/10: Macromolecular materials - A61L 31/16: Biologically active materials, e.g. therapeutic substances {(A61L31/047 takes precedence)} - B05D 1/36: Successively applying liquids or other fluent materials, e.g. without intermediate treatment - A61L 2300/606: Coatings - A61L 2300/608: having two or more layers - A61L 2400/18: Modification of implant surfaces in order to improve biocompatibility, cell growth, fixation of biomolecules, e.g. plasma treatment - A61L 2420/02: Methods for coating medical devices - A61L 2420/06: Coatings containing a mixture of two or more compounds - A61L 2420/08: Coatings comprising two or more layers - A61F: FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS (dental prosthetics A61C) - A61L: METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES (preservation of bodies or disinfecting characterised by the agents employed A01N; preserving, e.g. sterilising, food or foodstuffs A23; preparations for medical, dental or toiletry purposes A61K) - B05D: PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL (conveying articles or workpieces through baths of liquid B65G, e.g. B65G49/02) ## Abstract A medical implant for drug delivery comprising an inner layer of polymer material including a drug dispersed therein and an outer layer which may then mediate the release of the drug in a controllable manner. The outer layer may adhere and/or penetrate the underlying layer and offer a protective coating along with improved mechanical strength along with the ability to hydrate and become permeable to water and allow for drug release. ## Claims ### Claim 1 A method for coating the surface of an implant comprising: (a) coating the implant surface with a first layer of polymeric material that is either physically adhered and/or covalently bound to the implant surface; (b) coating the first layer of polymeric material with a second layer of polymeric material wherein the second layer of polymeric material includes a drug for delivery and wherein said second layer of polymeric material is either: (i) physically adhered to the first layer; and/or (ii) covalently bonded to the first layer; and/or (iii) joined to the first layer in the form of an interpenetrating polymer network; and (c) coating the second layer with a third outer layer wherein said third outer layer is either: (i) physically adhered to the second layer; and/or (ii) covalently bonded to the second layer; and/or (iii) joined to the second layer in the form of an interpenetrating polymer network; wherein said third layer has relatively higher mechanical strength than said first and second layers and is capable of hydration and said implant provides an initial cumulative drug release within 24 hours of administration of 0-95% and a sustained release of any remaining portion within a 14 day period. ### Claim 2 (depends on 1) The method of claim 1 wherein said first layer has a thickness of 10 nanometers to 100 nanometers. ### Claim 3 (depends on 1) The method of claim 1 wherein said second layer has a thickness of 100 nm to 500 μm. ### Claim 4 (depends on 1) The method of claim 1 wherein the outer layer of the insert comprises a polymer of the following formula: wherein R1 is selected from a hydrogen, alkyl group and/or an aromatic ring; R2 is selected from: (1) an alkyl group wherein at least one hydrogen on the alkyl group may be substituted with a hydrophilic type functional group; (2) ether and/or polyether type functionality. ### Claim 5 (depends on 4) The method of claim 4 wherein the polymer is poly-2-hydroxyethylmethacrylate and the value of n is greater than 34 to a value of 100. ### Claim 6 (depends on 1) The method of claim 1 wherein the surface of the implant includes a coupling agent to covalently bond said first layer to the surface of said implant. ### Claim 7 (depends on 1) The method of claim 1 wherein said outer layer is capable of absorbing 1.0% by weight to 50.0% by weight water. ### Claim 8 (depends on 1) The method of claim 1 wherein said implant is selected from a polymeric material and/or a ceramic material. ### Claim 9 (depends on 1) The method of claim 1 wherein said implant is a metallic material selected from the group consisting of Ti, Al, V, Cr, Fe, Co, Mo, Ni, Mn, Mg, Zr, and combinations thereof and/or stainless steels. ### Claim 10 (depends on 1) The method of claim 1 wherein said second layer comprises one or more of chitosan, collagen, gelatin, chitin, cellulose material, and/or PEG. ### Claim 11 (depends on 1) The method of claim 1 wherein said drug comprises an antibiotic, a statin, an anti-tumor agent, an anti-inflammatory agent; a therapeutic agent, an enzyme or cofactor; a cytokine; an anticoagulant; an immune system factor. ### Claim 12 (depends on 1) The method of claim 1 wherein said second layer and said outer layer have a thickness of 100 nm to 500 μm. ### Claim 13 (depends on 1) The method of claim 1 wherein said first layer of polymeric material includes surface functionality comprising amine, hydroxyl and/or carboxylic acid groups available for covalent bonding and/or interpenetrating network formation. ### Claim 14 (depends on 1) The method of claim 1 wherein said second layer of polymeric material includes surface functionality comprising amine, hydroxyl and/or carboxylic acid groups available for covalent bonding and/or interpenetrating network formation. ### Claim 15 A method for coating the surface of an implant comprising: (a) coating the implant surface with a first layer of polymeric material that is either physically adhered and/or covalently bound to the implant surface wherein said first polymer material includes surface functionality comprising amine, hydroxyl and/or carboxylic acid groups; (b) coating the first layer of polymeric material with a second layer of polymeric material wherein the second layer of polymeric material includes surface functionality comprising amine, hydroxyl and/or carboxylic acid and said second layer includes a drug for delivery and wherein said second layer of polymeric material is either: (i) physically adhered to the first layer; and/or (ii) covalently bonded to the first layer; and/or (iii) joined to the first layer in the form of an interpenetrating polymer network; and (c) coating the second layer with a third outer layer wherein said third outer layer is either: (i) physically adhered to the second layer; and/or (ii) covalently bonded to the second layer; and/or (iii) joined to the second layer in the form of an interpenetrating polymer network wherein said third outer layer comprises: wherein R1 is selected from a hydrogen, alkyl group and/or an aromatic ring; R2 is selected from: (1) an alkyl group wherein at least one hydrogen on the alkyl group may be substituted with a hydrophilic type functional group; (2) ether and/or polyether type functionality. ### Claim 16 (depends on 15) The method of claim 15 wherein said first layer has a thickness of 10 nanometers to 100 nanometers. ### Claim 17 (depends on 15) The method of claim 15 wherein said second layer has a thickness of 100 nm to 500 μm. ### Claim 18 (depends on 15) The method of claim 15 wherein the polymer is poly-2-hydroxyethylmethacrylate and the value of n is greater than 34 to a value of 100. ### Claim 19 (depends on 15) The method of claim 15 wherein the surface of the implant includes a coupling agent to covalently bond said first layer to the surface of said implant. ### Claim 20 (depends on 15) The method of claim 15 wherein said outer layer is capable of absorbing 1% by weight to 50% by weight water. ### Claim 21 (depends on 15) The method of claim 15 wherein said implant is selected from a polymeric material and/or a ceramic material. ### Claim 22 (depends on 15) The method of claim 15 wherein said implant is a metallic material selected from the group consisting of Ti, Al, V, Cr, Fe, Co, Mo, Ni, Mn, Mg, Zr, and combinations thereof and/or stainless steels. ### Claim 23 (depends on 15) The method of claim 15 wherein said second layer comprises one or more of chitosan, collagen, gelatin, chitin, cellulose material, and/or PEG. ### Claim 24 (depends on 15) The method of claim 15 wherein said drug comprises an antibiotic, a statin, an anti-tumor agent, an anti-inflammatory agent; a therapeutic agent, an enzyme or cofactor; a cytokine; an anticoagulant; an immune system factor. ### Claim 25 (depends on 15) The method of claim 15 wherein said second layer and said outer layer have a thickness of 100 nm to 500 μm. ### Claim 26 A method for coating the surface of an implant comprising: (a) coating the implant surface with a first layer of polymeric material that is either physically adhered and/or covalently bound to the implant surface and which includes a drug for delivery; (b) coating the first layer with a second outer layer wherein said second outer layer is either: (i) physically adhered to the first layer; and/or (ii) covalently bonded to the first layer; and/or (iii) joined to the first layer in the form of an interpenetrating polymer network; wherein said outer layer has relatively higher mechanical strength than said first layer and is capable of hydration and said implant provides an initial cumulative drug release within 24 hours of administration of 0-95% and a sustained release of any remaining portion within a 14 day period. ### Claim 27 An implant comprising: (a) an implant substrate including an outer surface wherein the implant is selected from one of: (i) a polymeric material; (ii) a ceramic material; or (iii) a metallic material selected from the group consisting of Ti, Al, V, Cr, Fe, Co, Mo, Ni, Mn, Mg, Zr, and combinations thereof and/or stainless steels; (b) a first layer of polymeric material that is either physically adhered and/or covalently bound to the implant surface; (c) a second layer of polymeric material wherein the second layer of polymeric material includes a drug for delivery and wherein said second layer of polymeric material is either: (i) physically adhered to the first layer; and/or (ii) covalently bonded to the first layer; and/or (iii) joined to the first layer in the form of an interpenetrating polymer network; and (d) a third outer layer wherein said third outer layer is either: (i) physically adhered to the second layer; and/or (ii) covalently bonded to the second layer; and/or (iii) joined to the second layer in the form of an interpenetrating polymer network; wherein said third layer has relatively higher mechanical strength than said first and second layers and is capable of hydration and said implant provides an initial cumulative drug release within 24 hours of implantation of 0-95% and a sustained release of any remaining portion within a 14 day period. ### Claim 28 An implant comprising: (a) an implant substrate including an outer surface wherein the implant is selected from one of: (i) a polymeric material; (ii) a ceramic material; or (iii) a metallic material selected from the group consisting of Ti, Al, V, Cr, Fe, Co, Mo, Ni, Mn, Mg, Zr, and combinations thereof and/or stainless steels; (b) a first layer of polymeric material including a drug for delivery wherein said polymer material is either physically adhered and/or covalently bound to the implant surface wherein said first polymer material includes surface functionality comprising amine, hydroxyl and/or carboxylic acid groups; (b) a second layer of polymeric material wherein said second layer is either: (i) physically adhered to the first layer; and/or (ii) covalently bonded to the first layer; and/or (iii) joined to the first layer in the form of an interpenetrating polymer network; and wherein said second layer comprises wherein R1 is selected from a hydrogen, alkyl group and/or an aromatic ring; R2 is selected from: (1) an alkyl group wherein at least one hydrogen on the alkyl group may be substituted with a hydrophilic type functional group; (2) ether and/or polyether type functionality.