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WO 2008/103464 Al (12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (19) World Intellectual Property Organization International Bureau (43) International Publication Date (10) International Publication Number 28 August 2008 (28.08.2008) PCT WO 2008/103464 Al (51) International Patent Classification: (74) Agents: QUINE, Jonathan, Alan et al. , Quine Intellectual A61F 2/02 (2006.01) Property Law Group, PC, P.O. Box 458, Alameda, CA (21) International Application Number: 94501 (US). PCT/US2008/002383 (81) Designated States (unless otherwise indicated, for every kind of national protection available): AE, AG, AL, AM, (22) International Filing Date: AO, AT,AU, AZ, BA, BB, BG, BH, BR, BW, BY,BZ, CA, 2 1 February 2008 (21.02.2008) CH, CN, CO, CR, CU, CZ, DE, DK, DM, DO, DZ, EC, EE, (25) Filing Language: English EG, ES, FI, GB, GD, GE, GH, GM, GT, HN, HR, HU, ID, (26) Publication Language: English IL, IN, IS, JP, KE, KG, KM, KN, KP, KR, KZ, LA, LC, LK, LR, LS, LT, LU, LY,MA, MD, ME, MG, MK, MN, (30) Priority Data: MW, MX, MY, MZ, NA, NG, NI, NO, NZ, OM, PG, PH, 11/677,680 22 February 2007 (22.02.2007) US PL, PT, RO, RS, RU, SC, SD, SE, SG, SK, SL, SM, SV, (71) Applicants (for all designated States except US): SY, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, NANOSYS, INC. [US/US], 2625 Hanover Street, Palo ZA, ZM, ZW Alto, CA 94304 (US). THE REGENTS OF THE UNI¬ (84) Designated States (unless otherwise indicated, for every VERSITY OF CALIFORNIA [US/US], 111 1 Franklin kind of regional protection available): ARIPO (BW, GH, Street, 12th Floor, Oakland, CA 94607-5200 (US). GM, KE, LS, MW, MZ, NA, SD, SL, SZ, TZ, UG, ZM, (72) Inventors; and ZW), Eurasian (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), (75) Inventors/Applicants (for US only): DESAI, Tejal European (AT,BE, BG, CH, CY, CZ, DE, DK, EE, ES, FI, [US/US], 3957 Sacramento Street, San Francisco, CA FR, GB, GR, HR, HU, IE, IS, IT, LT,LU, LV,MC, MT, NL, 941 18 (US). DANIELS, R., Hugh [US/US], 1144 Katie NO, PL, PT, RO, SE, SI, SK, TR), OAPI (BF, BJ, CF, CG, Court, Mountain View, CA 94040 (US). SAHI, Vijendra CI, CM, GA, GN, GQ, GW, ML, MR, NE, SN, TD, TG). [CA/US], 3637 Fair Oaks Avenue, Menlo Park, CA 94025 Published: (US). — with international search report [Continued on next page] (54) Title: MEDICAL DEVICE APPLICATIONS OF NANOSTRUCTURED SURFACES FIG 1 (57) Abstract: This invention provides novel nanofiber enhanced surface area substrates and structures comprising such substrates for use in various medical devices, as well as methods and uses for such substrates and medical devices. In one particular embod- iment, a method of administering a composition to a patient is disclosed which comprises providing a composition-eluting device, said composition-eluting device comprising at least a first surface and a plurality of nanostructures attached to the first surface, and introducing the composition-eluting device into the body of the patient. before the expiration of the time limit for amending the claims and to be republished in the event of receipt of amendments MEDICAL DEVICE APPLICATIONS OF NANOSTRUCTURED SURFACES CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims priority to U.S. Patent Application No. 11/677,680, filed February 22, 2007. FIELD OF THE INVENTION [0002] The invention relates primarily to the field of nanotechnology. More specifically, the invention pertains to medical devices containing nanostructures, composite materials containg nanostructures, methods of making medical devices containing nanostructures and methods of using medical devices containing nanostructures. BACKGROUND OF THE INVENTION [0003] Medical devices including, for example, intracorporeal or extracorporeal devices (e.g., catheters), temporary or permanent implants, stents, vascular grafts, anastomotic devices, aneurysm repair devices, embolic devices, and implantable devices (e.g., orthopedic or dental implants) are commonly infected with opportunistic bacteria and other infectious micro organisms, in some cases necessitating the removal of implantable devices. Such infections can also result in illness, long hospital stays, or even death. The prevention of biofilm formation and infection on indwelling catheters, orthopedic implants, pacemakers, contact lenses, stents, vascular grafts, embolic devices, aneurysm repair devices and other medical devices is therefore highly desirous. [0004] Enhancement of resistance of biomaterials to bacterial growth and promotion of rapid tissue integration and grafting of biomaterial surfaces are both areas of research. However, despite advances in sterilization and aseptic procedures as well as advances in biomaterials, bacterial and other microbial infection remains a serious issue in the use of medical implants. For example, greater than half of all nosocomial infections are caused by implanted medical devices. These infections are often the result of biofilms forming at the insertion site of the medical implant. Unfortunately, such infections are often resistant to innate immune system responses as well as to conventional antibiotic treatments. It will be appreciated that such infections are problematic not just in treatment of humans, but also in treatment of a number of other organisms as well. [0005] A welcome addition to the art would be medical devices having enhanced surface areas and structures/devices comprising such, as well as methods of using enhanced area surfaces in medical devices. The current invention provides these and other benefits which will be apparent upon examination of the following. SUMMARY OF THE INVENTION [0006] The embodiments of the current invention comprise various medical devices, such as clamps, valves, intracorporeal or extracorporeal devices (e.g., catheters), temporary or permanent implants, stents, vascular grafts, anastomotic devices, aneurysm repair devices, embolic devices, and implantable devices (e.g., orthopedic and dental implants) and the like which comprise nanostructure enhanced surfaces. The nanostructures may comprise nanofibers (including nanowires), nanotubes or nanoparticles and/or combinations thereof, and including woven and nonwoven fibrous mats comprising nanofibers and nanotubes. The nanostructures may be coated or uncoated, or have multiple coatings thereon. The specific coatings are described herein and vary depending on the desired purpose of the device or method. Such enhanced surfaces provide many enhanced attributes to the medical devices in, on, or within which they are used including, e.g., to prevent/reduce bio-fouling, increase fluid flow due to hydrophobicity, increase adhesion, biointegration, etc. [0007] In one aspect of the invention, a medical device is disclosed comprising a body structure having one or more surfaces having a plurality of nanostructured components associated therewith. The medical device may comprise an intracorporeal or extracorporeal device, a temporary or permanent implant, a stent, a vascular graft, an anastomotic device, an aneurysm repair device, an embolic device, an implantable device, a catheter, valve or other device which would benefit from a nanostructured surface according to the teachings of the present invention. The nanostructures may comprise nanofibers, nanotubes or nanoparticles and/or combinations thereof, and including woven and nonwoven fibrous mats comprising nanostructures. The nanostructures may be coated or uncoated, or have multiple coatings thereon. The specific coatings are described herein and vary depending on the desired purpose of the device or method. [0008] The plurality of nanostructured components enhance one or more of adhesion, non-adhesion, friction, patency or biointegration of the device with one or more tissue surfaces of a body of a patient depending on the particular application of the device. The nanofibers (or other nanostructured components) on the surfaces of the medical device can optionally be wholly or partially coated with any number of materials including biocompatible polymers, which may be flowable (e.g., for injecting into the body). The polymer can protect the wires during insertion into the body of a patient, and then, in certain embodiments, can be soluble to expose the nanowires in situ for their intended application (e.g., adhesion, cellular integration, and the like). In one embodiment, the nanowires can be embedded (e.g., potted) in a plastic or polymer matrix material such as PTFE, and then the material can be partially etched or otherwise partially removed (either in situ or ex situ) such that the plastic or polymer matrix can protect most of the length of each nanofiber, leaving only portions of the nanowires such as their ends exposed for their desired intended application (e.g., adhesion, cellular integration, anti- bifouling etc.). Thus, for example, nanostructures such as nanotubes and nanowires can be easily applied to low melting temperature plastics and polymers for various medical device applications as described more fully herein. Polymer chains can be formed in situ in a dilute aqueous solution primarily consisting of a monomer and an oxidizing agent. In one embodiment the polymer is created in the solution and subsequently spontaneously adsorbed onto the nanofiber surfaces as a uniform, ultra-thin film of between approximately 10 to greater than 250 angstroms in thickness. UV initiated polymerization can also be used to perform polymerization or any other suitable method can be used as would be known in the art. In one preferred embodiment of the present invention
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