HK1164355B - Non-fouling, anti-microbial, anti-thrombogenic graft-from compositions - Google Patents

Description

Non-fouling, antibacterial, antithrombotic graft-from complex

Technical Field

The invention is in the field of immobilized non-fouling coatings, in particular coatings that resist the attachment of biological materials and are attached to the surface of a substrate by the graft from method.

CROSS-REFERENCE TO RELATED APPLICATIONS

The following priority is claimed to the present application: U.S. S.N.61/120,285, entitled "synthetic antioxidant and antimogenie Polymers", filed by Zheng Zhang, William Shannan O' Shaughnessy, Michael Hencke, TrevorSquier and Christopher lose at 12.2008; U.S. s.n.61/120,292 entitled "Presentation of Immobilized Molecules" filed on 5.12.2008 by william shannan O' Shaughnessy, Victoria e.wagner Sinha, Zheng Zhang, Michael Hencke, Trevor Squier and Christopher los; U.S. S.N.61/120,312 entitled "Non-Fouling, anti-microbial gradient Coatings" was filed on 5.12.2008 by Trevor Squier, Zheng Zhang, William Shannano' Shanghany, Michael Hencke, Michael Bouchard and Christopher lose; and U.S. S.N.61/231,346 entitled "Non-Fouling, anti-rembotic Graft Coatings" filed on 5.8.2009 by Trevor Squier, Zheng Zhang, William Shannan O' Shaughessy, Michael Hencke, Michael Bouchard and Christopher lose.

Background

Many different materials have been investigated to make them resistant to non-specific protein adsorption. Chemicals that may be used for this purpose include, but are not limited to: polyethers (e.g., polyethylene glycol); polysaccharides, such as dextran; hydrophilic polymers such as polyvinylpyrrolidone or hydroxyethyl methacrylate, heparin, intramolecular zwitterions or mixed charged materials; and hydrogen bond accepting groups such as those described in US patent 7,276,286. The ability of these materials to prevent protein adsorption varies greatly between chemicals. Of these materials, only a few resist contamination to the extent required for short-term in vivo applications. However, these few materials suitable for short-term applications exhibit significant contamination or material degradation when used in complex media or in vivo for long periods of time, making them unsuitable for long-term applications. In addition, surfaces coated with materials that resist degradation in vivo are often sensitive and stain resistance decreases significantly over time.

WO 2007/02493 describes grafting of sulfobetaines (betaines) and carboxybetaines from self-assembled monolayers on gold substrates or from silyl groups on glass substrates using Atom Transfer Radical Polymerization (ATRP). Gold and glass are not suitable substrates for many medical devices used in living subjects. Self-assembled monolayers such as thiol-based monolayers may be unstable because the thiol groups cannot be stably bound to the substrate.

U.S. patent 6,358,557 to Wang et al describes graft polymerization of a substrate surface, but not grafting of a high density, highly non-fouling polymeric material. Thermal initiators are used to initiate the polymerization, typically at temperatures above 85 ℃. Such temperatures are generally not suitable for many medical devices, such as thin-walled polyurethane catheters. Furthermore, the "salting-out" method is generally not suitable for graft polymers, such as zwitterionic polymers.

Colloids and Surfaces B by Jianan et al: biointerfaces28, 1-9(2003) describe surface modification of segmented polyether urethanes by grafting of sulfoammonium amphoteric monomers, but not followed by high density non-fouling materials. The resulting material is not sufficiently non-fouling to be useful in medical device applications.

It is therefore an object of the present invention to provide a non-fouling polymeric coating for various substrates such as polymers and metal oxides, which remains active in the presence of blood proteins and/or in vivo due to an improved molecular structure, and which enables the immobilized substance to interact with protein-resistant chemicals to resist non-specific protein adsorption.

It is another object of the present invention to provide a non-fouling composite (composition) comprising a high density of non-fouling polymeric material and/or wherein the distance between the polymer chains of the non-fouling polymeric material reduces the penetration of fouling molecules into the non-fouling coating.

Yet another embodiment of the present invention is to provide a graft-from method of coating a surface comprised of a biomaterial wherein grafting is initiated from within the biomaterial to provide a material having a high density and stability of non-fouling polymers.

Invention of the inventionSUMMARY

Substrates from which one or more non-fouling materials have been grafted, optionally coated with an undercoating layer, are described herein. Non-fouling coatings with various attachment means of chemicals or polymer backbone chemicals provide an alternative approach to develop highly efficient, highly biocompatible, highly bioresponsive non-fouling coatings. In one embodiment, the coating is non-leaching (non-leaching). Conventional antifouling or non-fouling materials and surface coatings are susceptible to fouling with prolonged exposure to complex media and/or in vivo environments.

Non-fouling polymeric materials, particularly metal or polymeric substrates and/or polymeric undercoats, can be grafted from a variety of substrate materials using the chemistries described herein. The resulting polymeric coating is typically thicker than a self-assembly based monolayer coating and therefore better covers defects and irregularities in commercially available biomaterials, including polymeric and metallic materials, and thus a non-fouling coating is effective in complex media and/or in vivo.

Compared with the access type grafting formula, the access type grafting technology can obtain higher surface density of the non-fouling material. A high concentration of polymerization initiator can be incorporated into the substrate or undercoat layer, for example, by swelling the substrate or undercoat layer in the presence of the initiator. High concentrations of initiator in and/or on the substrate and/or undercoat layer can provide a high density of polymer chains on the surface. In one embodiment, the density of polymer chains on the surface is about 0.5 μ g/cm²To about 5mg/cm²About 1. mu.g/cm²To about 100. mu.g/cm²Or about 2. mu.g/cm²To about 50. mu.g/cm². In an alternative embodiment, the inter-polymer chain distance reduces the penetration of fouling molecules into the coating material.

The graft-from method can be used to produce covalently linked polymers that exhibit a high degree of uniformity of the non-fouling groups and will exhibit the highest degree of non-fouling activity. The coating may be grafted from substrates of various shapes, including tubular and porous structures.

The complexes described herein preferably resist adsorption of more than 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 99%, or 99.9% of protein from a solution, such as Phosphate Buffered Saline (PBS) containing protein, media, serum, or living organisms over 1, 7, 14, 21, 30, 45, 60, 90, 120, 180, 365, or 1000 days as compared to an uncoated control.

The complexes described herein are stable over extended periods of time, maintaining at least 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 99% of their non-fouling, anti-thrombotic, and/or antibacterial properties in protein-containing PBS, in culture medium, serum, or in vivo for extended periods of time, e.g., for at least 1, 7, 14, 21, 30, 45, 60, 90, 120, 180, 365, or 1000 days.

The non-fouling material may be grafted from the substrate, or optionally from an undercoating layer on the substrate, without significantly affecting the mechanical and/or physical properties of the substrate material. In one embodiment, the difference in tensile strength, modulus, device size, or a combination thereof of the coated substrate is within 20%, preferably within 10%, more preferably within 5%, most preferably within 1% of the tensile strength, modulus, device size, or a combination thereof of the uncoated substrate.

Brief Description of Drawings

Fig. 1 shows the total surface thrombus volume (mg) of UV carboxybetaine coated Tecoflex rods and uncoated Tecoflex rods.

Detailed Description

I. Definition of

"zwitterionic" or "zwitterionic material" refers to a macromolecule, material, or moiety that has both cationic and anionic groups. In most cases, these charged groups are balanced and the resulting material has zero net charge. Zwitterionic polymers can include polyampholytes (e.g., polymers with charged groups on different monomer units) and polybetaines (polymers with anionic and cationic groups on the same monomer unit).

As used herein, "polymer" includes homopolymers and copolymers. Examples of copolymers include, but are not limited to, random copolymers and block copolymers.

As used herein, "antimicrobial" refers to molecules and compositions that kill (i.e., disinfect), inhibit the growth of (i.e., inhibit the growth of), and/or prevent the contamination of microorganisms, including bacteria, yeast, fungi, mycoplasma, viruses, or cells infected with viruses, cancer cells, and/or protozoa.

The antibacterial activity against bacteria is preferably measured by a colony assay method in which 50% fetal calf serum is pre-incubated at 120RPM and 37 ℃ for 18-20 hours. After preculture, the samples were placed in staphylococcus aureus (s. aureus, ATCC 25923), which had been diluted from an overnight culture in 1% tryptone soy medium (TSB) to a plankton concentration of 1-3 × 10⁵CFU/mL. The samples were incubated with the bacteria at 37 ℃ for 24-26 hours with agitation (120 rpm). The TSB concentration varies with the organism used. After incubation, the samples were placed in 3ml PBS at 37 deg.C for 5 minutes at 240RPM to remove loosely adhering bacteria. The bacteria accumulated on the material were transferred to a fresh PBS solution by sonication and the total number of bacterial cells was quantified by dilution plating. Preferably at least a 1,2, 3 or 4 log reduction in bacterial count occurs relative to colonies on the control. Similar attachment assays for assessing the attachment of platelets, cells, or other materials to a surface are known in the art. A surface having a lower bacterial count thereon compared to the reference polymer may be said to reduce the proliferation of microorganisms.

As used herein, "antithrombotic" refers to the ability of the complex to resist thrombosis. Antithrombotic activity can be measured using an extracorporeal flow cycle model of thrombosis. Briefly, fresh blood was collected from a single animal up to 10 liters. The blood was heparinized to prevent clotting, filtered to remove particulates and autologous radioisotope-labeled platelets added. Within 8 hours after harvesting the blood, the coated or uncoated substrate is placed in a flow circulation loop that pumps the blood from the fluid bath, through the substrate and back into the fluid bath. The two ends of the substrate can be connected by a second peristaltic pump to establish a second internal flow circulation loop for the substrate containing the lumen. Blood was pumped in the outer loop at a rate of about 2.5L/min, and in the inner loop at a rate of about 200 and 400 ml/min. After two hours, the matrix was removed, the thrombus formation was visually inspected and the attached platelets were quantified using a gamma counter. For samples without lumen, the thrombus outside the device was measured with only the outer loop.

As used herein, "attached" refers to the non-covalent or covalent attachment of a protein, cell, or other substance to a surface. The amount of the attached substance can be quantified, and a non-pollution activity analysis method is adopted for the protein; for bacteria, assays for antimicrobial activity or other related assays are employed.

"bioactive agent" or "active agent" or "biomolecule," used synonymously herein, refers to any organic or inorganic therapeutic, prophylactic or diagnostic agent that actively or passively affects a biological system. For example, the bioactive agent can be an amino acid; an antimicrobial peptide; an immunoglobulin; activating molecules, signaling molecules, or signal amplifying molecules, including but not limited to protein kinases, cytokines, chemokines, interferons, tumor necrosis factors, growth factor inhibitors, hormones, enzymes, receptor-targeted ligands, gene silencing agents, ambisense molecules (ambisense), antisense molecules, RNA, living cells, coherence, laminin, fibronectin, fibrinogen, osteocalcin, osteopontin, or osteoprotegerin. The bioactive agent may be a protein, glycoprotein, peptide, oligopeptide, polypeptide, inorganic compound, organometallic compound, organic compound, or any synthetic or natural chemical or biological compound.

As used herein, "non-fouling" refers to an amount of adhesion of a complex to reduce or prevent the adhesion of proteins, including blood proteins, plasma, cells, tissues, and/or microorganisms, to a substrate relative to the amount of adhesion to a reference polymer, such as polyurethane. Preferably, the surface of the device is substantially non-fouling in the presence of human blood. Preferably, the amount of adhesion is reduced by 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 70%, 75%, 80%, 85%, 90%, 95%, 99%, 99.5% or 99.9% relative to the reference polymer.

The non-fouling activity on proteins, also known as "protein resistance", can be measured using an ELISA assay. For example, the ability of a complex to prevent adhesion of fibrin can be assessed by measuring the adsorption of fibrinogen by ELISA. Fibrinogen is a blood protein commonly used to assess the anti-adsorption capacity of non-fouling surfaces based on its important role in regulating platelet and other cell adhesion. Briefly, samples were incubated in 1mg/mL fibrinogen from human plasma at 37 ℃ for 90 minutes, then washed three times with 1 XPBS and transferred to clean wells. The samples were incubated in 10% (v/v) foetal calf serum at 37 ℃ for a further 90 minutes to block the regions not occupied by fibrinogen. The samples were washed, transferred to clean wells, and incubated with 5.5ug/mL horseradish peroxidase-conjugated anti-fibrinogen in 10% (v/v) fetal calf serum for 1 hour. The sample was washed and transferred to a clean well containing 1mg/mL of o-phenylenediamine chromogen and 0.02% (v/v) of hydrogen peroxide in 0.1M phosphate-citrate buffer. Incubation at 37 ℃ for 20 minutes resulted in an enzyme-induced color reaction, which was stopped by the addition of 2.0N sulfuric acid. The absorbance of the light intensity can then be measured with a microplate reader to determine protein adsorption relative to the control. Preferably, the amount of adhesion is reduced by at least 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 99%, 99.5%, 99.9% relative to the reference polymer. For protein mixed solutions, such as whole plasma, Surface Plasmon Resonance (SPR) or light wavelength guided optical spectroscopy (OWLS) can be used to measure surface protein adsorption without being forced to use a separate antigen for each protein present in the solution. In addition, proteins labelled with radioisotopes can be quantified from the surface after adsorption of one protein or a complex mixture.

"biocompatibility" is the ability of a material to perform a response to an appropriate host under particular circumstances. Can be evaluated using the international standard ISO 10993. The biocompatible composites described herein are preferably substantially non-toxic. As used herein, "substantially non-toxic" refers to surfaces that are substantially hemocompatible and substantially non-cytotoxic.

"substantially non-cytotoxic" as used herein refers to such a complex: which alters the metabolism, proliferation or survival of mammalian cells in contact with the surface of the complex. These changes can be measured by the international standard ISO 10993-5, which defines three main tests to evaluate the cytotoxicity of materials, including the extract test, the direct contact test and the indirect contact test.

As used herein, "substantially hemocompatible" means that the complex is substantially nonhemolytic and non-thrombogenic and non-immunogenic when determined using a suitably selected assay for thrombosis, hemagglutination and complement activation as described in ISO 10993-4.

As used herein, "substantially nonhemolytic surface" means that the complex does not lyse 50%, preferably 20%, more preferably 10%, even more preferably 5%, most preferably 1% of human red blood cells when the following assay is used: a10% stock of washed pooled red blood cells (RocklandImmunochemicals Inc, Gilbertsville, Pa.) was diluted to 0.25% with 150mM NaCl and 10mM Tris, pH 7.0, hemolysis buffer. 0.5cm was washed with 0.75ml of a 0.25% red blood cell suspension²The antibacterial sample of (2) was incubated at 37 ℃ for 1 hour. The solid sample was removed, 6000g of cells were vortexed, the supernatant was removed, and OD414 was measured on a spectrophotometer. Total lysis was determined by diluting 10% of the washed stock red blood cells to 0.25% in sterile deionized water (DI) and incubating at 37 ℃ for 1 hourBlood, 0% hemolysis was defined using a suspension of 0.25% erythrocytes in hemolysis buffer without solid sample.

As used herein, "complex medium" refers to a biological fluid or solution containing protein or digests of biological material. Examples include, but are not limited to: cation-regulated Mueller Hinton medium, tryptone soy medium, brain-heart infusion, or any number of complex media, as well as any biological fluid.

"biological fluids" are fluids produced by protein-containing organisms and/or cells, as well as fluids and excretions from microorganisms. These include, but are not limited to: blood, saliva, urine, cerebrospinal fluid, tears, semen, lymph fluid or any derivative thereof (e.g. serum, plasma).

"Brush" or "polymer brush" are used synonymously herein to refer to a polymer chain that is bound to a surface, typically via a single point connection. The polymers may be terminally grafted (attached via a terminal group) or attached via a side chain or non-terminal position on the polymer chain. The polymers may be straight-chain or branched. For example, the polymer chains described herein may comprise a plurality of zwitterionic group-containing side chains. The side chains can be composed of a single non-fouling moiety or monomer and/or non-fouling oligomer (e.g., 2-10 monomers) or polymer (e.g., > 10 monomers).

"branched" and "branched tether" are used interchangeably to refer to a polymeric structure that originates from a single polymer chain, but terminates in two or more polymer chains. The polymer may be a homopolymer or a copolymer, and the branched-tethered polymer structure may be ordered or random, may be comprised in whole or in part of a non-fouling material, and may be used to immobilize one or more bioactive agents. In one embodiment, the branched tether is a dendrimer. The branched tether may be directly affixed to the substrate or to an undercoating covering the substrate.

"degradation products" are atoms, radicals, cations, anions, or molecules formed as a result of hydrolysis, oxidation, enzymatic, or other chemical processes.

As used herein, "density" refers to the fixed mass of material per unit surface area of the substrate, including, but not limited to, non-fouling materials and bioactive agents.

As used herein, "inter-polymer chain distance" refers to the distance between non-fouling polymer chains on the surface of a substrate or undercoat layer. Preferably, the distance is such that the non-fouling chain reduces the penetration of fouling molecules into the coating material.

As used herein, "effective surface density" refers to a range of densities suitable to achieve a desired surface effect, including, but not limited to, antimicrobial or non-fouling activity as defined herein.

"hydrophilic" refers to a polymer, material, or functional group that has an affinity for water. Such materials typically include one or more hydrophilic functional groups, such as hydroxyl groups, zwitterionic groups, carboxyl groups, amino groups, amide groups, phosphate groups, hydrogen bond-forming groups, and/or ether groups.

As used herein, "immobilized" or "immobilized" refers to a material or bioactive agent that is covalently or non-covalently attached, directly or indirectly, to a substrate. "Co-immobilization" refers to the immobilization of two or more reagents.

As used herein, "non-degradable" refers to a complex of materials that does not undergo significant hydrolysis, reduction, enzymatic or oxidation reactions in a biological environment to break down into smaller or simpler components.

As used herein, "stable" means that the material retains at least 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 70%, 75%, 80%, 85%, 90%, 95%, or 99% of its original material properties, such as surface contact angle, non-staining, anti-thrombotic, and/or anti-bacterial activity, in PBS containing protein, culture medium, serum, or over a period of 1, 7, 14, 30, 90, 365, or 1000 days in vivo.

As used herein, "substrate" refers to a material having a primer and/or a non-fouling coating applied thereon, or a material formed in whole or in part from a non-fouling material, or a material having a non-fouling and/or antimicrobial agent immobilized thereon.

As used herein, "coating" refers to any temporary, semi-permanent, or permanent single or multiple layers that treat or cover a surface. The coating may be a chemical modification of the base substrate or may also include the addition of new materials to the substrate surface. Including any increase in substrate thickness or change in the surface chemical composition of the substrate. The coating may be a gas, vapor, liquid, paste, semi-solid, or solid. In addition, the coating may be applied as a liquid and cured to a solid coating.

"undercoat" means any coating, combination of coatings, or functional layer that covers the entire substrate surface or a portion thereof, underlying an additional layer.

"non-leaching" or "substantially non-leaching" are used synonymously herein to mean that the complex remains more than 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 99% of the immobilized coating or bioactive agent in PBS containing protein, culture medium, serum, or in vivo for a period of 7, 14, 30, 90, 365, or 1000 days. Which can be assessed using a radiolabeled active agent.

"tethering" or "tethering agent" or "linking agent," as used synonymously herein, refers to any molecule, group of molecules, or polymer used to covalently immobilize one or more non-fouling materials, one or more bioactive agents, or a combination thereof, to a material, wherein the molecule remains as part of the final chemical makeup. The tether may be a straight or branched chain with one or more sites for immobilizing the bioactive agent. The tether may be of any length. In one embodiment, however, the tether is greater than 3 angstroms in length. The tether may be non-fouling, such as a monomeric, oligomeric, or polymeric or non-fouling non-zwitterionic material. The tether may be directly fixed to the matrix or polymer, both of which may be non-fouling.

As used herein, a "non-naturally occurring amino acid" refers to any amino acid that is not found in nature. Unnatural amino acids include any D-amino acid, amino acids with side chains not found in nature, and peptidomimetics. Examples of peptidomimetics include, but are not limited to: b-peptide, g-peptide, and d-peptide; oligomers having a backbone that can adopt a helical or sheet conformation, such as: a compound having a skeleton utilizing a bipyrimidine moiety, a compound having a skeleton utilizing solvophobic interaction, a compound having a skeleton utilizing side chain interaction, a compound having a skeleton utilizing hydrogen bonding interaction, and a compound having a skeleton utilizing metal coordination. All amino acids in the human body, except glycine, exist in D and L forms. Almost all naturally occurring amino acids are in the L form. The D-amino acids are not present in proteins of higher organisms, but are present in some lower forms of life, such as in the cell wall of bacteria. They are also present in some antibiotics, such as streptomycin, actinomycin, bacitracin, and tetracycline. These antibiotics can kill bacterial cells by interfering with the formation of proteins required for survival and reproduction. Non-naturally occurring amino acids also include residues having side chains that resist non-specific protein adsorption, which may be designed to enhance the presence of antimicrobial peptides in biological fluids; and/or polymerizable side chains that enable the synthesis of polymer brushes with unnatural amino acid residues in the peptide as monomer units.

"Polypeptides", "peptides" and "oligopeptides" comprise organic compounds composed of natural amino acids, synthetic amino acids, or mixtures thereof chemically linked via peptide bonds. Peptides typically contain 3 or more amino acids, preferably more than 9 and less than 150, more preferably less than 100, most preferably 9-51 amino acids. The polypeptide may be "exogenous" or "heterologous," i.e., a polypeptide that is produced in an organism or cell in which the production of the peptide does not naturally occur, such as a human polypeptide produced by a bacterial cell. Exogenous also refers to a substance that is not naturally present in a cell but is added to a cell, as compared to endogenous material produced by the cell. A peptide bond comprises a monovalent linkage between the carboxyl group (oxygen-bearing carbon) of one amino acid and the amino nitrogen of a second amino acid. Small peptides having less than about 10 component amino acids are commonly referred to as oligopeptides, and peptides having more than 10 amino acids are referred to as polypeptides. Compounds with molecular weights above 10,000 daltons (50-100 amino acids) are commonly referred to as proteins.

As used herein, "antimicrobial peptide" ("AmP") refers to an oligopeptide, polypeptide, or peptidomimetic that kills (i.e., sterilizes) or inhibits the growth of (i.e., inhibits) microorganisms, including bacteria, yeast, fungi, mycoplasma, viruses, or virus-infected cells and/or protozoa.

As used herein, "coupling agent" refers to any molecule or chemical that activates a chemical moiety, e.g., on a bioactive agent or on a material to which it is to be attached, such that covalent or non-covalent bonds are formed between the bioactive agents, wherein the substance is not retained in the final composition after attachment.

As used herein, "cysteine" refers to the amino acid cysteine or a synthetic analog thereof, wherein the analog contains a free sulfhydryl group.

As used herein, "membrane-targeted antimicrobial agent" refers to any antimicrobial agent that retains its bactericidal or bacteriostatic activity when immobilized on a substrate and thus can be used to create an immobilized antimicrobial surface. In one embodiment, the membrane-targeted antimicrobial agent is an antimicrobial peptide; in another embodiment, it is a quaternary ammonium compound or polymer.

As used herein, "immobilized bactericidal activity" refers to the reduction of viable microorganisms on the contact surface, including bacteria, yeast, fungi, mycoplasma, viruses or virus-infected cells, and/or protozoa. For bacterial targets, bactericidal activity can be quantified as a reduction in viable bacteria based on the ASTM2149 assay method for immobilized antibacterial agents, and for small samples, can be scaled down as follows: the target bacteria are cultured overnight in a growth medium such as cation-regulated Mueller Hinton medium, using a pre-calibrated ratio between OD600 and cell density, at pH 7.4Diluting to about 1X 10 in phosphate buffer⁵cfu/ml. Is measured at a distance of 0.5cm²The immobilized antimicrobial surface sample was added to 0.75ml of the bacterial suspension. The sample should be covered with liquid and should be incubated at 37 ℃ and mixed sufficiently, i.e. to ensure that the solid surface rotates through the liquid. After 1 hour incubation, serial dilutions of the bacterial suspension were spread onto agar plates and allowed to grow overnight to quantify viable cell concentration. Preferably, at least 1,2, 3 or 4 log reductions in bacterial count occur relative to a control of bacteria in Phosphate Buffered Saline (PBS) without solid sample.

The term "alkyl" refers to a saturated or unsaturated aliphatic group, including straight-chain alkyl, alkenyl, and alkynyl groups, branched-chain alkyl, alkenyl, or alkynyl groups, cycloalkyl (alicyclic), cycloalkenyl, and cycloalkynyl groups, alkyl-, alkenyl-, or alkynyl-substituted cycloalkyl, cycloalkenyl, or cycloalkynyl groups, and cycloalkyl-substituted alkyl, alkenyl, or alkynyl groups. In a preferred embodiment, the linear or branched alkyl group has 30 or less carbon atoms in its backbone (e.g., linear is C)₁-C₃₀The branched chain is C₃-C₃₀) Preferably 20 or less carbon atoms, more preferably less than 10 carbon atoms, and most preferably less than 7 carbon atoms. Likewise, preferred cycloalkyl groups have 3 to 10 carbon atoms in their ring structure, more preferably 5, 6 or 7 carbon atoms in the ring structure.

It is understood that "substituted" or "substituted" includes the implicit proviso that such substitution is in accordance with the allowed valency of the atom or atoms to be substituted for the substituent, and that the substitution results in a stable compound that, for example, does not spontaneously undergo transformations such as rearrangement, cyclization, or elimination.

The term "substituted" as used herein is intended to encompass all permissible substituents of organic compounds. Broadly, the permissible substituents include aliphatic and alicyclic, branched or unbranched, carbocyclic and heterocyclic, aromatic and nonaromatic substituents of organic compounds. Exemplary substituents include, but are not limited to: an aryl group; a heteroaryl group; a hydroxyl group; halogen; an alkoxy group; a nitro group; mercapto, sulfonyl; amino (substituted or unsubstituted); an acylamino group; amide (amidio); an alkylthio group; carbonyl groups such as esters, ketones, aldehydes, and carboxylic acids; thiocarbonyl groups, sulfonate, sulfate, sulfonamido, sulfamoyl and sulfoxide groups.

For suitable organic compounds, the permissible substituents can be one or more and the same or different. For purposes of the present invention, a heteroatom such as nitrogen may have a hydrogen substituent and/or any permissible organic compound substituent described herein that satisfies the valence of the heteroatom. The polymers described herein are not meant to be limited in any way by permissible substituents of organic compounds.

II. Complex body

A. Substrate

The graft-grafting of the non-fouling material can be carried out from a variety of different substrates or base coats fixed to the substrates. Examples of suitable materials include, but are not limited to: metallic materials, ceramics, polymers, woven or non-woven fibers, inert materials such as silicon, and combinations thereof. In one embodiment, the substrate is a material that is not gold or glass.

Suitable metallic materials include, but are not limited to: titanium-based metals and alloys, such as unalloyed titanium (ASTM F67) and titanium alloys such as ASTM F1108, Ti-6Al-4V ELI (ASTM F136), Nitinol (ASTM F2063), Nitinol, and thermal memory alloy materials; stainless steel (ASTM F138 and F139); tantalum (ASTM F560); palladium; zirconium; niobium; molybdenum; a nickel-chromium alloy; or certain cobalt alloys including Stellite, cobalt chromium alloys (Villium, ASTM F75 and refined cobalt chromium alloys (ASTM F90)), and cobalt chromium nickel alloys such asAnd

suitable ceramic materials include, but are not limited to: oxides, carbides or nitrides of transition elements, such as oxides of titanium, hafnium, iridium, chromium, aluminum and zirconium. Silicon-based materials such as silicon dioxide may also be used.

Suitable polymeric materials include, but are not limited to: polystyrene and substituted polystyrene; polyolefins such as polyethylene and polypropylene; a polyurethane; polyacrylates and polymethacrylates; polyacrylamide and polymethacrylamide; a polyester; a polysiloxane; a polyether; a polyorthoester; a polycarbonate; polyhydroxyalkanoate; a polycarbofluoro compound; PEEK; teflon; a silicone resin; an epoxy resin;nylon; a polyolefin; phenolic resin, PTFE; natural and synthetic elastomers; adhesives and sealants; a polyolefin; polysulfones; polyacrylonitrile; biopolymers such as polysaccharides and their natural latex copolymers, and combinations thereof. In one embodiment, the substrate is a medical grade polyurethane orAliphatic polycarbonate-based polyurethanes, available from Lubrizol corporation, are mixed with suitable extrusion agents and plasticizers, one of which may have been approved by the FDA or other suitable regulatory agency for use in vivo.

The matrix may also optionally contain radiation-shielding additives, such as barium sulfate or bismuth, to aid in radiographic imaging.

The matrix may be or form part of: a film; particles (nanoparticles, microparticles, or millimeter-sized beads); fibers (wound dressings, bandages, gauze, tapes, pads, sponges, including woven or non-woven sponges and those specifically designed for dental or ophthalmic surgery); surgical, medical or dental instruments; a blood oxygenator; a ventilator; a pump; a drug delivery device; a tube; a wire; an electrode; a contraceptive device; feminine hygiene products; an endoscope; grafts (including small diameters < 6mm in diameter); stents (including coronary, ureteral, renal, biliary, colorectal, esophageal, pulmonary, urethral, and vascular); stent grafts (including abdominal, thoracic, peripheral vascular); a pacemaker; an implantable cardioverter-defibrillator; a cardiac resynchronization therapy apparatus; a cardiovascular device lead; ventricular assist devices and drivetrain; a heart valve; a vena cava filter; an intravascular coil; catheters (including central venous, peripheral central, midline, peripheral, tunneled, dialysis-accessed, catheterization, neurological, peritoneal, intra-aortic balloon pump, angioplasty balloon, diagnostic, interventional, drug delivery, etc.); catheter connectors and valves (including needle connectors); intravenous delivery lines and manifolds; a flow divider; wound drains (internal or external, including ventricular, ventricular and peritoneal, lumbar and peritoneal); a dialysis membrane; an infusion port; a cochlear implant; an endotracheal intubation; a tracheostomy tube; a ventilation breathing tube and a circuit; a guide wire; a fluid collection bag; drug delivery bags and tubes; implantable sensors (e.g., intravascular, percutaneous, and intracranial); ophthalmic devices, including contact lenses; orthopedic devices (including hip implants, knee implants, shoulder implants, spinal implants (including cervical plating systems, pedicle screw systems, interbody fusion devices, artificial discs, and other motion protection devices), screws, plates, rivets, rods, intramedullary nails, bone cement, artificial tendons, and other prosthetic or fracture repair devices); a dental implant; a periodontal implant; a breast implant; a penile implant; a maxillofacial implant; a cosmetic implant; a valve; an appliance; a working frame; a suture material; a needle; a hernia repair mesh; tension-free vaginal tape and vaginal sling; a neurological repair device; tissue regeneration and cell culture devices; or other devices used within or in contact with the body, or any portion of any of these devices.

In one embodiment, the substrate is a catheter for insertion into the vasculature, such as an exogenously inserted central catheter (PICC), Central Venous Catheter (CVC), or hemodialysis catheter, venous catheter, or the likeA vein valve, a punctual plug, and an intraocular device or implant. In another embodiment, the substrate is made of medical grade polyurethane orFormed of or coated with medical grade polyurethane orThe material of (a) forms a vein-like inserted catheter.

Non-fouling materials can also be added to paints and other coatings and filters to prevent mold, bacterial contamination, and other applications where fouling resistance is desired, such as marine applications (boat hull coatings); a fuel tank; an oil pipeline; an industrial pipeline; a pharmaceutical device; drug delivery devices such as inhalers; a contact lens; a dental implant; an in vivo sensor coating; textiles such as hospital curtains, hospital gowns or bedding; a ventilation duct; a door handle; separation devices, such as membranes for microbial suspensions, biomolecule separations, protein fractionation, cell separation, wastewater treatment, water purification, bioreactors, and food processing.

These materials can also be used to treat the surface of fibers, particles and films for textiles, additives, electrical/optical appliances, packaging materials and colorants/inks.

The matrix may contain an initiator to initiate polymerization from the surface. For example, such a matrix may initially have radicals absorbed in the surface or in the matrix and may, for example, initiate polymerization of the polymer chains. For example, a substrate such as polyurethane may be treated to form free radicals within and/or on the substrate.

In some embodiments, the substrate is substantially free of thiol groups, that is, the substrate does not contain thiol moieties, such as thiol linkers. In another embodiment, the substrate may further comprise a primer layer applied to the surface of the substrate. Also contemplated herein are substrates having two or more surfaces that cannot be simultaneously exposed to a light source.

1. Effective surface area

In addition to the chemical composition of the substrate, the micro-and nano-scale structure of the substrate surface also facilitates maximizing the surface area available for the attachment of non-fouling materials and/or antimicrobial agents. For metal or ceramic substrates, the surface area may be increased by surface roughening, for example by random processes, such as plasma etching. Alternatively, the surface may be modified by controlled nanoimprinting using photolithography techniques. The polymer matrix may also be roughened like a metal or ceramic matrix. For alternative applications, creating a smooth or flatter surface enhances the non-staining properties of the material. The surface may be modified to enhance adhesion and stability of the primer. Alternatively, the surface may be polished or smoothed to reduce the surface area, which also reduces the physical characteristics of the trapped contaminants. Furthermore, a defined roughness with a specific size and distribution of physical features may control the interaction of bacteria, proteins and other contaminants with the surface. Each of these roughness variables can be enhanced by the addition of a non-fouling coating.

2. Surface microstructure

In cases where a greater density of non-fouling material is desired, the creation of a microstructure on the surface of the substrate can create more regions for grafting non-fouling material from the surface without increasing the apparent surface area of the substrate. For polymer matrices, including hydrogel networks, such surface morphology can be constructed by appropriate polymer structure design. An example of such a morphology is the growth of surface-attached dendrimers. The generation of each dendrimer effectively doubles the number of zwitterionic sites present. Other polymer structures include brush polymers, such as brush copolymers; comb polymers, such as comb copolymers; linear or branched copolymers; a crosslinked polymer; a hydrogel; polymer mixtures, and combinations thereof.

B. Non-fouling material

Surfaces that resist non-specific protein adsorption are important in the development of biomedical materials, such as medical devices and implants. Such coatings limit the interaction between the implant and the physiological fluid. In environments where the fluid contains high concentrations of biological proteins, such as in applications where it contacts blood, preventing protein adsorption can prevent contamination and/or thrombosis of the device surface.

1. Zwitterionic materials

A zwitterion is a molecule that carries formal positive and negative charges on non-adjacent atoms within the same molecule. Both natural and synthetic polymers containing zwitterionic functional groups have been shown to resist protein attachment. In one embodiment, the zwitterionic monomer contains a phosphorylcholine moiety, a sulfobetaine moiety, a carboxybetaine moiety, a derivative thereof, or a combination thereof. Phosphorylcholine (PC), a naturally amphiphilic molecule, treated substrate surfaces exhibit not only reduced protein adsorption, but also increased hemocompatibility compared to untreated substrate surfaces. Polymers constructed from phosphorylcholine, in addition to exhibiting the above properties, are also considered to be biomimetic.

Sulfobetaine, very close to 2-aminoethanesulfonic acid, is one of the low molecular weight organic compounds most abundantly present in animals. Sulfobetaine monomers are generally easier to handle than phosphorylcholine, and the resulting polymers are generally easier to synthesize than the corresponding phosphorylcholine analogs.

Polycarboxybetaines are polymeric analogs of naturally occurring zwitterionic alanine betaines. Like polyphosphazenes and polysulfonobetaines, polycarboxybetaines are another class of zwitterionic, biomimetic polymers that are otherwise resistant to biological contamination. These polymers are particularly well suited for blood-contacting applications due to the unique antithrombotic and anticoagulant properties of carboxybetaines. In addition to these properties, the carboxybetaine monomers can be designed such that the resulting polymer contains reactive functional groups for immobilization of biologically active molecules. By creating a carboxybetaine brush on the surface, the dual function of being resistant to proteins or platelets and having an active anticoagulant group, the amount of thrombus on the surface can be further reduced compared to employing either strategy alone.

The polysulfonyl and polycarboxybetaines are not only biomimetic, but also have a high resistance to bacterial adhesion, biofilm formation and adsorption of non-specific proteins from serum and plasma, they are also non-toxic, biocompatible and they generally exhibit a higher stability in complex media or in vivo than do the degraded polyphosphazenes and polyethylene glycols. The application of these materials and coatings can be further extended with bioactive agents such as antimicrobial peptides.

Other natural or synthetic zwitterionic chemicals can also be used to design non-fouling materials for biomedical applications as described herein. Some examples of natural zwitterionic chemicals that can be used in the non-fouling material include, but are not limited to: an amino acid; a peptide; natural small molecules, including but not limited to N, N-trimethylalanine (alanine betaine), trimethylamine oxide (TMAO), dimethylsulfonium propionate sarcosine, lysergic acid, and gymnosporine. Additional synthetic zwitterionics that may be used to create non-fouling materials include, but are not limited to: aminocarboxylic acids (carboxybetaines); sulfamic acids (sultaines); cocoamidopropyl betaine; zwitterions based on quinones; decaphenyl ferrocene; and unnatural amino acids. Natural and synthetic polymers also include mixed charge structures with both positively and negatively charged moieties on pendant groups in the backbone or on terminal groups.

To improve biocompatibility, reduce thrombosis (e.g., on the surface of a stent or venous valve), and reduce contamination by proteins or bacteria present in solution, materials containing or consisting of these natural or synthetic zwitterions may be coated onto surfaces, particularly the surface of medical devices. This applies in particular to surfaces: non-specific binding of proteins in solution can negatively impact the desired or required structure of the device.

In one embodiment, the non-fouling material is a zwitterionic polymer grafted from a substrate. For example, the polymer may contain one or more monomers of formula I:

wherein B is selected from the following groups:

wherein R is selected from hydrogen, substituted alkyl or unsubstituted alkyl;

e is selected from the group consisting of substituted alkyl, unsubstituted alkyl, - (CH)₂)_yC (O) O-and- (CH)₂)_yC(O)NR²；

Y is an integer of 0 to 12;

l is absent or is a linear or branched alkyl group, optionally containing one or more oxygen atoms;

ZI is a zwitterionic group; and

x is an integer of 3 to 1000.

In a particular embodiment, the ZI is selected from:

wherein R is₃And R₄Independently selected from hydrogen and substituted or unsubstituted alkyl;

R₅selected from substituted or unsubstituted alkyl, phenyl and polyether groups; and

m is an integer from 1 to 7.

In another embodiment, the polymer contains one or more monomers of formula II:

wherein B is₁And B₂Independently selected from:

r is selected from hydrogen and substituted or unsubstituted alkyl;

e is selected from substituted or unsubstituted alkenyl, - (CH)₂)_pC (O) O-, and- (CH)₂)_pC(O)NR²-, where p is an integer of 0 to 12,

R²selected from hydrogen and substituted or unsubstituted alkyl;

l is a linear or branched alkenyl group, optionally containing one or more oxygen atoms;

P₁is a positively charged group;

P₂being negatively charged radicals, e.g. carboxylate radicals or SO₃ ^-A group;

m is an integer of 3 to 1000; and

n is an integer from 3 to 1000.

In one embodiment, the positively charged group is a moiety containing a quaternary nitrogen or cationic phosphorus group and the negatively charged group is a moiety containing a carboxylic acid group, SO₃ ^-Or PO₃ ^-A moiety of a group.

In another embodiment, the polymer contains one or more monomers of formula III, IV or V:

wherein R is selected from substituted or unsubstituted alkyl;

L₁、L₂and L₃Independently a straight or branched chain alkenyl group, optionally containing one or more oxygen atoms; and

n is an integer from 3 to 1000; and

n1 is an electronegative group, e.g. carboxylate, SO₃ ^-Or PO₃ ^-A group.

In one embodiment, the non-fouling material is a polymer containing monomers derived from sulfobetaines or carboxybetaines. Examples of monomers include sulfobetaine methacrylate (SBMA) or carboxybetaine methacrylate (CBMA). Examples of such polymers include, but are not limited to: poly (carboxybetaine methacrylate) (polyCBMA) and poly (sulfobetaine methacrylate) (polySBMA). In another embodiment, the non-fouling material polymer is a polymer comprising CBMA or SBMA and one or more other monomers. The other monomer may be a zwitterionic or non-zwitterionic monomer.

In certain embodiments, an antibacterial and/or antithrombotic complex is provided comprising a substrate, such as a polyurethane, to which a plurality of polymer chains are covalently attached. For example, such polymer chains may be represented by formulas I, II, III, IV, and V. In a certain embodiment, the non-fouling material is a brush structure comprising one or more monomers of formulae I, II, III, IV, and V. In yet another embodiment, the non-fouling material is a copolymer containing one or more monomers represented by formulas I, II, III, IV, and V.

In some embodiments, the composite is an antimicrobial composite comprising a polymer matrix and a zwitterionic polymer covalently linked to the polymer matrix. The zwitterionic polymer can be formed by: in the presence of one or more monomers, such as sulfobetaine methacrylate or carboxybetaine methacrylate monomers, the polymerization reaction thereof with the groups present in the polymer matrix is initiated.

Also provided herein is a composite comprising a zwitterionic polymer covalently linked to a polymer matrix, wherein the polymer composite has improved non-fouling, antibacterial and/or antithrombotic activity as compared to a polymer comprised of zwitterionic and non-zwitterionic monomers. In another embodiment, a polymer composite is provided comprising a zwitterionic polymer covalently attached to a polymer substrate, wherein the composite exhibits improved non-fouling, antibacterial, and/or antithrombotic activity as compared to a composite having a zwitterionic polymer attached to a self-assembled monolayer that is immobilized to the substrate via thiol moieties.

2. Non-zwitterionic materials

The non-fouling coating may also contain non-zwitterionic non-fouling materials, either alone or in combination with zwitterionic materials. These non-fouling groups may have varying degrees of non-fouling properties over a range of environments. Suitable non-zwitterionic materials include, but are not limited to: polyethers such as polyethylene glycol, poly (ethylene oxide-co-propylene oxide) (PEO-PPO) block copolymers; polysaccharides, such as dextran; hydrophilic polymers such as polyvinylpyrrolidone (PVP) and hydroxyethyl methacrylate (HEMA); acrylonitrile-acrylamide copolymers; heparin; mixing the charged materials; and materials containing hydrogen bond accepting groups such as those described in US 7,276,286. Suitable polymeric structures include, but are not limited to, polymers or copolymers containing monomers of formula I wherein ZI is replaced by non-zwitterionic non-fouling end groups.

3. Comonomer

The non-fouling polymer grafted from the surface of the substrate may be a copolymer, such as a random or block copolymer. Suitable comonomers include, but are not limited to: an acrylate; (ii) acrylamide; a vinyl compound; multifunctional molecules such as di-, tri-and tetraisocyanates, di-, tri-and tetraols, di-, tri-and tetraamines, di-, tri-and tetrathiocyanates; cyclic monomers such as lactones and lactams; and combinations thereof. Exemplary monomers are listed below:

(1) charged methacrylates or methacrylates having primary, secondary or tertiary amine groups, such as the potassium salt of 3-sulfopropyl methacrylate, [ (2-dimethylamino) ethyl acrylate ] methyl chloride quaternary salt, [2- (methacryloyloxy) ethyl ] trimethyl ammonium chloride, methacryloyl chloride, [3- (methacryloylamino) propyl ] -trimethyl ammonium chloride, the hydrochloride of 2-aminoethyl methacrylate, 2- (diethylamino) ethyl methacrylate, 2- (dimethylamino) ethyl methacrylate, 2- (tert-butylamino) ethyl methacrylate, and 2- (tert-butylamino) ethyl methacrylate.

(2) Alkyl methacrylates or other hydrophobic methacrylates, such as ethyl methacrylate, butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, methyl methacrylate, lauryl methacrylate, isobutyl methacrylate, isodecyl methacrylate, phenyl methacrylate, decyl methacrylate, 3, 3, 5-trimethylcyclohexyl methacrylate, benzyl methacrylate, cyclohexyl methacrylate, stearyl methacrylate, tert-butyl methacrylate, tridecyl methacrylate, 2-naphthyl methacrylate, 2, 2, 3, 3-tetrafluoropropyl methacrylate, 1, 1, 1,3, 3-hexafluoroisopropyl methacrylate, 2, 2, 2-trifluoroethyl methacrylate, 2, 2, 3, 3, 3-pentafluoropropyl methacrylate, 2, 3, 4, 4, 4-hexafluorobutyl methacrylate, 2, 3, 3, 4, 4, 4-heptafluorobutyl methacrylate, 2, 3, 3, 4, 4, 5, 5-octafluoropentyl methacrylate, 3, 3, 4, 4, 5, 5, 6, 6,7, 7, 8, 8, 8-tridecafluorooctyl methacrylate and 3, 3, 4, 4, 5, 5, 6, 6,7, 7, 8, 8, 9, 9, 10, 10, 10-heptadecafluorodecyl methacrylate.

(3) Reactive or crosslinkable methacrylates, such as 2- (trimethylsiloxy) ethyl methacrylate, 3- (trichlorosilyl) propyl methacrylate, 3- (trimethoxysilyl) propyl methacrylate, 3- [ tris (trimethylsiloxy) silyl ] propyl methacrylate, trimethylsilyl methacrylate, allyl methacrylate, vinyl methacrylate, 3- (acryloyloxy) -2-hydroxypropyl methacrylate, 3- (diethoxymethylsilyl) propyl methacrylate, 3- (dimethylchlorosilyl) propyl methacrylate, 2-isocyanatoethyl methacrylate, glycidyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxyethoxy methacrylate, 3- (trimethoxysilyl) propyl methacrylate, 3- (dimethylchlorosilyl) propyl methacrylate, 2-isocyanatoethyl methacrylate, glycidyl methacrylate, 2-hydroxyethoxy methacrylate, and mixtures thereof, 3-chloro-2-hydroxypropyl methacrylate, hydroxybutyl methacrylate, glycerol methacrylate, hydroxypropyl methacrylate, and 2-hydroxypropyl 2- (methacryloyloxy) ethyl phthalate.

(4) Other methacrylates, such as ethylene glycol methyl ether methacrylate, di (ethylene glycol) methyl ether methacrylate, ethylene glycol phenyl ether methacrylate, 2-butoxyethyl methacrylate, 2-ethoxyethyl methacrylate, ethylene glycol divinyl ether methacrylate.

Condensed type monomers may also be used.

Acrylamide and/or methacrylamide derivatives of the monomers listed above, as well as other monomers bearing unsaturated bonds, may also be used.

Multifunctional monomers such as di-, tri-, or tetraacrylates can be used to form highly branched structures that can provide higher concentrations of non-fouling groups on the surface.

4. Density of non-fouling material

Having an increased density of the non-fouling chains improves the non-fouling performance. Shortening the inter-polymer chain distance improves performance and can be achieved by having a more concentrated initiator concentration. This can be achieved by either absorbing the initiator into the matrix or having an undercoat layer that acts as or incorporates a high density initiator. Longer polymer chains and/or branched non-fouling chains may further improve performance.

In one embodiment, the surface has a high surface polymer chain density. In one embodiment, the density of polymer chains on the surface is from about 0.5. mu.g/cm²To about 5mg/cm²From about 1ug/cm²To about 100ug/cm²From about 2ug/cm²To about 50ug/cm². In an alternative embodiment, the inter-polymer chain distance is such as to reduce the penetration of contaminants into the coating material, for example < 5nm, < 10nm, < 50nm, or < 100 nm.

C. Fluorescent and chromogenic labels

In one embodiment, the surface is colored or labeled with one or more chromogenic labels, fluorescent labels, or a combination thereof. The use of these markings allows the surface to be visualized with the naked eye, spectrophotometer, microscope, or combinations thereof. Suitable microscopy techniques include, but are not limited to, optical microscopy, fluorescence microscopy, and combinations thereof.

The surface may be colored by chemical reaction or by physical adsorption, such as charge-charge interaction, hydrophobic interaction, or hydrophilic interaction. Marker compounds include, but are not limited to, rhodamine, fluorescein, coumarin, orange B, crystal violet, toluidine blue, methyl violet, fast red, methylene blue, malachite green, magenta, acridine yellow, and other azo compounds.

In another embodiment, the surface is modified, for example, to be zwitterionic polymer-labeled, by incorporating one or more reactive labeling monomers into the polymer backbone during the polymerization reaction. These tagged monomers include, but are not limited to: FITC-methacrylate, FITC-acrylate, rhodamine-methacrylate, rhodamine-acrylate, derivatives thereof or any other fluorescent acrylate, methacrylate, acrylamide, vinyl compounds, diols or diamines. The combination of these substrates allows for convenient measurement of the consistency and/or coating thickness. These can be particularly advantageous as a quality control measure for consistency verification during the manufacture of coatings on a base device.

In another embodiment, the surface modification is colored with one or more compounds that are readily visible under an electron microscope (SEM or TEM). These compounds include, but are not limited to, osmium tetroxide and ruthenium tetroxide.

D. Bioactive agents

Therapeutic, diagnostic and/or prophylactic agents can be immobilized onto a substrate. These agents may interact with the surrounding in vivo environment passively or actively in vivo. The agents may also be used to alter the surrounding chemistry and environment in the body. Two or more agents may be immobilized on the surface of the substrate, where both agents are more active than either agent alone. A substance, material or agent that is not considered active can become active if the active agent is immobilized to the substance, material or agent. Active agents include, but are not limited to, inorganic compounds, organometallic compounds, organic compounds, or any synthetic or natural chemical or biological compound having a known or unknown therapeutic effect.

Cell adhesion agents may be immobilized to the complexes described herein. The efficacy of cell adhesion agents in binding cells in complex environments can be enhanced by reducing adsorption of non-specific proteins from surfaces on which they are present, provided that cell adhesion is a process that can compete with adsorption of other proteins. Furthermore, the use of cell adhesion agents to resist the adhesion of any of those non-specifically targeted cells is advantageous in preventing competitive blocking of the surface.

Examples of desirable cell adhesion agents include, but are not limited to, integrin binding agents. Exemplary integrin binding agents include, but are not limited to, RGD peptides, as well as a number of variants comprising an RGD peptide motif. Longer variants of this peptide may have more specific targeted cell binding. Furthermore, the ability to provide locally thicker concentrations of cell adhesion agents can enhance the efficacy of cell adhesion by building multimeric interactions. Other cell adhesion agents include, but are not limited to, REDV peptides. Specific integrin binders are useful for a variety of applications, including osteointegration.

Cell adhesion agents that bind to specific immune cells may also benefit from the adhesion of zwitterions. Adhesion of immune cells to the surface of the biomaterial activates these cells and acts as a prelude to their phenotypic response, e.g., monocyte migration to macrophages can in some cases lead to fusion as an undesirable foreign body, giant cells. The inherent resistance of zwitterions to contamination by any protein provides a unique platform for conjugation of biomolecules that act as specific ligands for immune cells, including neutrophils and monocytes. Selection of appropriate ligands can provide these cells with favorable conditions without compromising function. These ligands include peptides and proteins that specifically bind to immune cell receptors, such as integrins, selectins, complement or Fc γ. When bound to these cell-associated proteins, such ligands stimulate intracellular signaling pathways, leading to responses that include cytoskeletal rearrangement, production and secretion of molecules including chemokines, cytokines, and other chemoattractants, and induction of apoptosis. Biomolecules may be presented via zwitterionic linkages to modulate desired behavior, which may include preventing/reducing secretion of pro-inflammatory cytokines, enhancing phagocytosis, and modulating release of soluble factors that affect tissue-device integration.

Osteointegration may also be promoted or initiated by factors that benefit from the non-fouling nature and the stable presence of non-fouling materials such as zwitterions. Osteointegration promoters include, but are not limited to, osteoplastin proteins, such as BMP2 and its shortened analogs. Non-fouling surfaces, such as zwitterionic surfaces, can enhance the activity of agents designed to promote the re-growth of desired cells on the surface. Reducing neutrophil and macrophage adhesion can inhibit foreign body reactions and can promote desired cell adhesion and growth processes.

Presentation of the antithrombotic agent is also more effective when linked to a non-fouling material, such as a zwitterionic material, relative to other linkages. The process of thrombosis involves both surface and bulk pathways. Zwitterions have been shown to reduce platelet adhesion and activation, reducing one way. Active antithrombotic agents help to reduce platelet activation or directly target other pathways of thrombosis, which in combination with zwitterionic tethers can enhance the antithrombotic effect, compared to either the surface without platelet attachment or just the antithrombotic agent. Suitable antithrombotic agents include, but are not limited to: thrombomodulin; heparin; a reversible albumin binding agent; tissue plasminogen activator binding agent; transglutaminase (transcutonase); a reversible NO binding agent; a polylysine; a sulfonated polymer; thrombin inhibitors, including hirudin, urokinase and streptokinase.

Device-centric infections leave a number of problems. Non-fouling materials, such as zwitterionic materials, can themselves reduce microbial attachment and retard biofilm formation. The presence of antimicrobial agents, including but not limited to: membrane-targeted antibacterial agents, antibacterial peptides, and small molecule antibacterial agents. Typically, antimicrobial peptides are cationic molecules with spatially isolated hydrophobic and charged regions. Exemplary antimicrobial peptides include linear peptides that form an alpha-helical structure within the membrane and peptides that form a beta-sheet structure within the membrane, the sheet structure optionally being stabilized by disulfide bonds. Representative antimicrobial peptides include, but are not limited to, spirodiclodin (cathelicidin), defensin, dermcidin, more particularly magainin 2, protegrin-1, melittin, II-37, dermaseptin 01, cecropin, calein, ovispirin, cecropin a melittin hybrid, and dermaseptin, or other amps hybrids or analogs. Naturally occurring antimicrobial peptides include peptides from vertebrates and non-vertebrates, including plants, humans, fungi, bacteria, and insects.

The antimicrobial peptides can be prepared from naturally occurring amino acids, non-naturally occurring amino acids (e.g., synthetic or semi-synthetic amino acids and peptidomimetics), or combinations thereof. Antimicrobial agents that retain their activity when immobilized to a surface are commonly referred to as membrane-targeted antimicrobial agents. The antimicrobial peptide can be immobilized onto the non-fouling coating, substrate, primer, or a combination thereof by reacting the functional groups on the peptide with the functional groups on the non-fouling coating, substrate, and/or primer. For example, the peptide may be designed to have a cysteine residue that can be used to immobilize the peptide to a surface by reacting a thiol group on the cysteine residue with a thiol-reactive group on the surface.

The attachment of these agents to non-fouling materials such as zwitterions should provide stable long-term activity. Furthermore, immobilization of enzymes that degrade bacterial adhesion and biofilm proteins, such as glucosyl enzymes, lyases, serine proteases, or those that degrade microbial signaling molecules, such as N-acyl-homoserine lactone acyltransferases, can provide improved efficacy in preventing initial microbial adhesion events and subsequent biofilm formation.

Non-fouling surfaces, such as zwitterionic surfaces, may also provide a particularly attractive surface for the immobilization of biomolecules, such as antibodies, for use as biosensors. Antibodies immobilized on non-fouling surfaces such as zwitterionic surfaces have been shown to retain their antibody activity and antigen specificity in whole blood. The "smart" implantable medical device can be designed to detect the activation of undesired specific immune pathways, such as pro-inflammatory cytokines, or possibly the presence of possible infectious agents by detecting secreted microbial toxins, for example using specific antibodies or biomolecules suitable for monitoring these threats. Appropriate treatment regimens can then be employed prior to adverse consequences, such as infection. The stability of the zwitterionic molecule in vivo provides unique benefits in such cases due to its durability.

Method for producing coated substrates

The non-fouling coating constructed by the graft-from process is highly resistant to contamination by proteins, bacteria or other substances. Methods of preparing these coated substrates are described below.

A. Primer or precoating

Medical device substrates are often constructed from a variety of different materials, each having individual surface properties. Even devices composed primarily of a single polymer will be composed of a mixture of materials and may contain plasticizers, radio-opacifying agents, and other agents, all of which can affect the surface properties of the substrate. To ensure a uniform surface composition to maximize coating adhesion and effectiveness, a pre-coat of a single polymer or polymer blend may be provided on the substrate. In one embodiment, the primer layer comprises a single polymer. The polymer may be deposited onto the substrate by a variety of techniques known in the art, such as solvent casting or impregnation, and once coated onto the substrate, the primer layer is optionally covalently crosslinked. The use of a single polymeric primer layer, for example, enables the formation of a coating surface having a uniform identity and concentration of functional groups.

The undercoating layer may contain a radiation shielding agent, such as BaSO₄Or bismuth, to assist in radiographic imaging of the substrate. In one embodiment, the polymer is Tecoflex-93A or Carbothane 85A, optionally containing 0-40 wt% BaSO₄。

The primer layer may also include, but is not limited to: polymers, such as: polystyrene and substituted polystyrenes, polyethylene, polypropylene, polyurethane, polyacrylate and polymethacrylate, polyacrylamide and polymethacrylamide, polyester, polysiloxane, polyether, polyorthoester, polycarbonate, polyhydroxyalkanoate, fluorocarbon, PEEK, Teflon, silicone, epoxy, silicone, polyurethane,nylon, polyalkenes, phenolic resins, PTFE, natural and synthetic elastomers, adhesives and sealants, polyolefins, polysulfones, polyacrylonitriles; biopolymers such as polysaccharides and their natural latex copolymers, and combinations thereof. In another embodiment, the primer layer contains small molecules or functional groups including, but not limited to, hydroxyl, amino, carboxyl, azido, azo, alkyl, alkenyl, alkynyl, and siloxane groups. These functional groups can serve as anchor points, from which non-fouling materials are grafted and/or adhesion promotersTherapeutic, diagnostic or prophylactic agents.

Coating a titanium substrate with a high density non-fouling coating may include surface modification to direct the functional groups of the titanium surface to covalently bond with the coating. For example, a solution of oxidized goby can be used to build hydroxyl groups on the surface of a substrate. These groups can then be used to covalently link to an anchoring molecule that provides an organofunctional moiety. Alternatively, an oxide layer of titanium may be grown on the surface of the titanium by heating in air at very high temperatures, for example 773-.

Functional groups that anchor the undercoat to the titanium include, but are not limited to, silane, phosphonic acid, and catechol groups. For example, trimethoxysilane and trichlorosilane can be introduced onto the surface of a titanium substrate by exposing the substrate to a silane solution. The functional groups may be in the form of small molecules, oligomers, and/or polymers, including copolymers.

The precoated substrate was then further functionalized with the coating method described below.

B. Grafting-out method

The composites described herein are typically prepared by graft-from grafting. The non-fouling material can be grafted directly from the substrate surface by growing the polymer from the reactive functional groups on the substrate surface. Alternatively, the substrate may be coated with a primer layer from which the polymer grows.

The graft-off process can produce a stable and dense, non-fouling coating that grows directly on the substrate surface. Because small initiator molecules can be packed more densely on and/or in the surface of the substrate and/or basecoat layers that initiate and propagate the polymerization reaction, a much higher coating density can be achieved with this method relative to coatings obtained by the graft-on method, as compared to larger polymer molecules synthesized in solution. Preferably, for the manufacture of medical devices, the chemicals used must be stable and able to overcome small surface defects. The chemistry required to form self-assembled monolayers (SAMs) or other single molecule initiator layers is unlikely to produce a manufacturable coating. For these applications, procedures that do not require strict control of reaction conditions (oxygen-free, anhydrous solvents, etc.) are preferred.

The reactivity ratios of the monomers can be designed to enable the production of alternating copolymers, block copolymers having a predetermined ratio of the monomers, and random copolymers or homopolymers. The presence of more than two reactive groups per monomer unit enables the formation of star polymers, dendrimers, regular branched polymers, random branched polymers, and brush polymers.

Polymer brushes, combs, linear or branched copolymers, dendrimers, tethers, and hydrogels can be formed by known synthetic methods, including but not limited to: radical polymerization, ionic polymerization, Atom Transfer Radical Polymerization (ATRP), Nitroxide Mediated Polymerization (NMP), reversible addition-fragmentation polymerization (RAFT), Ring Opening Metathesis Polymerization (ROMP), telluride mediated polymerization (TERP), or acyclic diene metathesis polymerization (ADMET), as well as UV, thermal, or redox radical polymerization. In a preferred embodiment, the polymer is formed using a redox polymerization process.

1. Non-free radical process

Graft polymerization reactions of the graft-type can be propagated by cationic or anionic reactions, in which the surface of the substrate acts as a cationic or anionic initiator or a cationic or anionic initiator is fixed to the substrate and the monomer contains a reactive olefin. An example of anionic polymerization is anionic ring opening, for example in the case of the synthesis of polycaprolactone or polycaprolactam, where the polymerization is carried out via a lactone or lactam moiety in a ring structure containing pendant zwitterionic groups. Alternatively, an organic ring containing one or more units of unsaturation is polymerized with a pendant zwitterionic group. In one embodiment, the pendant olefin is included in a monomer unit and is used for crosslinking, for example in a Ring Opening Metathesis Polymerization (ROMP).

The functional group can be introduced by carrying out a graft polymerization reaction of the graft-out type in various ways. For example, three may also be usedThe fluoromethanesulfonic acid treats the silicone polymer to introduce SiH groups, which can then be used to attach silicone chains containing suitable functional groups to a surface. The polyurethane matrix may employ CO₂、O₂And ammonia plasma treatment. The resulting hydroxyl and/or amine groups can be acrylated to form vinyl moieties on the surface, followed by tethering of the polymer brush. Alternatively, amine functionality can be introduced onto the surface of the polyurethane substrate by aminolysis by treatment with a diamino molecule such as hexamethyldiamine. Semi-or fully interpenetrating polymer networks can be used to incorporate the amino-bearing polymer into the polyurethane matrix.

In another embodiment, the polymerization reaction is initiated by functionalizing the surface of the substrate with small molecules such as azides or terminal alkynes and exposing the substrate to an interaction between one or more different monomers each containing two or more active sites of a single type. For example, a monomer containing two azide functional groups is reacted with the substrate surface followed by a monomer containing two terminal alkynes.

2. Free radical process

In one embodiment, the non-fouling polymeric material is grafted from the substrate using a free radical polymerization process. The polymerization conditions described herein are generally milder than other polymerization processes and therefore do not significantly alter the mechanical, elastic or dimensional properties of the base matrix.

Examples of free radical polymerization processes include, but are not limited to, UV, thermal or redox initiated processes. In particular embodiments, the coating is grown directly from the surface of the substrate by first absorbing or adsorbing one or more initiators, such as ultraviolet, thermal, or redox initiators, into or onto the surface of the substrate, and then initiating polymerization of one or more monomers from the surface. The polymerization reaction is typically initiated by exposing the initiator-imbibed matrix to a solution or suspension of the monomer or monomers to be polymerized.

Chain transfer agents may be added to the monomer solution to adjust the kinetics of the graft-type free radical graft polymerization reaction. Chain transfer agents include, but are not limited to, molecules comprising halocarbons, thiols, dithiocarbamates, trithiocarbonates, dithioesters, xanthates. Examples of chain transfer agents are bromotrichloromethane and 4-methylphenylsulfitol. In one embodiment, the grafting of the free-radical polymerization is regulated with 2, 2, 6, 6-tetramethylpiperidin-1-oxyl (TEMPO). In one embodiment, grafting of the free radical polymerization reaction is mediated with a Reversible Addition Fragmentation Transfer (RAFT) agent.

For graft-off processes that require an initiator, the initiator can be added to the surface of the substrate by a variety of methods. In one embodiment, the initiator is added to or on the surface of the substrate by physical adsorption, wherein the initiator is dissolved in a solvent or a combination of solvents. The substrate is soaked in a solvent or solvent combination containing an initiator for a predetermined amount of time. Swelling the substrate and/or primer layer and eventually drawing the initiator near the surface of or into the substrate. The amount of initiator introduced into the substrate can be controlled by varying the solution concentration of the initiator in the solvent and/or by varying the time the substrate is immersed in the initiator solution.

In another embodiment, the initiator is added to the substrate surface or primer layer by chemisorption. In this embodiment, the initiator contains a reactive group that will chemically react with the surface of the substrate to form a chemical bond between the substrate and the initiator.

In another embodiment, the initiator is added to the substrate surface by co-deposition of the initiator molecule with other materials. For example, the initiator may be dissolved into the polymer solution. By immersion of the substrate in this solution, a thin film of polymer and initiator is deposited onto the substrate. The initiator may initiate polymerization directly or indirectly on the surface of the substrate, or on the co-deposited material. Examples of materials that are co-deposited include, but are not limited to Tecoflex,Polyurethane, polystyrene, polyester or sol-gel.

In yet another embodiment, the initiator is incorporated directly into the backbone of the coating material, such as a brominated polyurethane. In this embodiment, the coating is applied directly to the surface of the substrate and polymerization is initiated directly from the coating.

For a clear surface, the chain graft density can be increased by increasing the initiator concentration by absorption or priming. Having a higher chain graft density, the permeation of contaminant molecules into the coating can be reduced by increasing the number of non-fouling groups and/or increasing the number of shortened inter-polymer chain distances, resulting in a non-fouling polymer that better prevents the permeation of contaminants into the coating. In one embodiment, the initiator is absorbed (adsorbed) into or onto the surface of the substrate. For example, the substrate may be exposed to a solution of the initiator in an organic solvent. The solvent is capable of swelling the matrix, enabling adsorption of the initiator into the matrix. The extent of adsorption into the matrix is a function of the amount and duration of swelling of the matrix.

As noted above, oxygen can act as an inhibitor of free radical polymerization because it can rapidly react with the free radicals generated by the initiator to form stable free radical species which can then react with other free radical species to form unreactive species, causing the polymerization reaction to terminate. Thus, the creation of an oxygen-free environment by degassing with nitrogen or argon or by evacuation before or during the polymerization reaction is often used to remove oxygen. However, in commercial production, it is preferred that such a degassing step is not required.

Alternatively, the oxygen in the system can be minimized by filling the reactor with the reaction mixture to physically displace the oxygen in the reactor. In another embodiment, an oxygen scavenging agent is added to the reaction mixture. Suitable oxygen scavengers include, but are not limited to, sodium periodate, riboflavin, and ascorbic acid. These agents may increase the effectiveness of the resulting polymer if the polymerization is carried out under non-inert conditions.

UV initiators

In one embodiment, the initiator is an Ultraviolet (UV) initiator. The free-radical polymerization of the graft-off on the substrate surface is generally initiated by placing the substrate and initiator in a degassed aqueous solution containing the zwitterionic monomer and then exposing to UV light.

UV free radical initiators include, but are not limited to: 1-hydroxycyclohexyl phenyl ketone, 2-diethoxy acetophenone, 2-benzyl-2- (dimethylamino) -4 '-morpholinopropyl phenyl ketone, 2-hydroxy-2-methyl propiophenone, 2-hydroxy-4' - (2-hydroxyethoxy) -2-methyl propiophenone, 2-methyl-4 '- (methylthio) -2-morpholinopropiophenone, 3' -hydroxyacetophenone, 4 '-ethoxyacetophenone, 4' -hydroxyacetophenone, 4 '-phenoxyacetophenone, 4' -tert-butyl-2 ', 6' -dimethylacetophenone, diphenyl (2, 4, 6-trimethylbenzoyl) phosphine oxide/2-hydroxy-2-methyl propiophenone, and mixtures thereof, 2, 2-dimethoxy-2-phenylacetophenone, 4, 4 ' -dimethoxy benzoin, 4, 4 ' -dimethyl benzil, benzoin ethyl ether, benzoin isobutyl ether, benzoin methyl ether, benzoin, 2-methylbenzophenone, 3, 4-dimethyl benzophenone, 3-hydroxybenzophenone, 3-methylbenzophenone, 4, 4 ' -bis (diethylamino) benzophenone, 4, 4 ' -dihydroxy benzophenone, 4, 4 ' -bis [2- (1-propenyl) phenoxy ] phenoxide]Benzophenone, 4- (diethylamino) benzophenone, 4-benzoyldiphenyl, 4-hydroxybenzophenone, 4-methylbenzophenone, benzophenone-3, 3 ', 4, 4' -tetracarboxylic dianhydride, benzophenone, methyl benzoylformate, michelione, sulfonium, iodonium2- (4-methoxystyryl) -4, 6-bis (trichloromethyl) -1, 3, 5-triazine and diphenyl iodideP-toluenesulfonate, N-hydroxy-5-norbornene-2, 3-dicarboximide perfluoro-1-butaneAlkanesulfonate, N-hydroxynaphthalimide triflate, 2-tert-butylanthraquinone, 9, 10-phenanthrenequinone, anthraquinone-2-sulfonic acid sodium salt monohydrate, camphorquinone, diphenyl (2, 4, 6-trimethylbenzoyl) phosphine oxide, 10-methylphenothiazine, thioxanthone, and IRGRCURE 2959.

Thermal initiator ii

In another embodiment, a thermally activated (thermal) initiator is used instead of the UV initiator described above, and the graft polymerization reaction of the graft-type is initiated by heating the temperature of the aqueous monomer solution to the desired temperature and keeping this temperature constant until the polymerization reaction is complete.

Suitable thermal initiators include, but are not limited to: peroxybenzoate, 4-azobis (4-cyanovaleric acid), 2 '-azobis [ (2-carboxyethyl) -2-methylpropionamidine ], 2' -azobis (4-methoxy-2, 3-dimethylvaleronitrile), 1 '-azobis (cyclohexanecarbonitrile), 2' -Azobisisobutyronitrile (AIBN), benzoyl peroxide, 2-bis (t-butylperoxy) butane, 1-bis (t-butylperoxy) cyclohexane, 2, 5-bis (t-butylperoxy) -2, 5-dimethylhexane, 2, 5-bis (t-butylperoxy) -2, 5-dimethyl-3-hexyne, bis (1- (t-butylperoxy) -1-methylethyl) benzene, bis (1-carboxyethyl) -2-methylpropionamidine, 2 '-azobis (2-carboxyethyl) -2-methylpropionamidine, 2' -azobis (4-methoxy-2-, 1, 1-bis (t-butylperoxy) -3, 3, 5-trimethylcyclohexane, t-butyl hydroperoxide, t-butyl peracetate, t-butyl peroxide, t-butyl perbenzoate, t-butyl peroxycarbonate isopropyl, cumene hydroperoxide, cyclohexanone peroxide, dicumyl peroxide, lauroyl peroxide, 2, 4-pentanedione peroxide, peracetic acid, potassium persulfate.

The temperature to which the solution is heated depends on the monomer and/or initiator. Examples of thermal free radical initiators include, but are not limited to, azo compounds such as Azobisisobutyronitrile (AIBN) and 1, 1' -azobis (cyclohexanecarbonitrile) (ABCN). The graft polymerization reaction was quenched by rapidly cooling the reaction solution in liquid nitrogen.

Redox initiators

In another embodiment, a redox initiator system is used to initiate polymerization from the surface of the substrate. Redox initiator systems typically include a pair of initiators: an oxidizing agent and a reducing agent. The redox species described herein can be modified to produce non-fouling polymeric materials, for example, brush shapes, such as zwitterionic polymeric brushes. The redox initiation process is considered to be the most efficient one-electron transfer reaction that efficiently generates free radicals under mild conditions.

Suitable oxidizing agents include, but are not limited to: peroxides, persulfates, peroxodisulfates, perdiphosphates, permanganates, salts of metals such as Mn (III), Ce (IV), V (V), Co (III), Cr (VI) and Fe (III).

Suitable reducing agents include, but are not limited to: metal salts such as fe (ii), cr (ii), v (ii), ti (iii), cu (ii), and ag (i), oxoacids of sulfur, hydroxy acids, alcohols, thiols, ketones, aldehydes, amines, and amides.

The polymerization reaction may be initiated by a large radical formed by abstracting a hydrogen atom from the substrate directly from a radical generated by the redox reaction and/or by a transient radical formed during the redox reaction.

In one embodiment, the substrate is coated with an undercoat layer, and the non-fouling material is grafted from the undercoat layer by redox polymerization. The undercoat layer contains an oxidizing agent and a reducing agent. In a preferred embodiment, the primer layer contains one or more reducing agents, such as acids, alcohols, thiols, ketones, aldehydes, amines and amides. The oxidizing agent is used to react with one or more functional groups of the primer layer to generate groups that initiate graft polymerization reactions of the graft-type.

In a particular embodiment, the primer layer is a copolymer with pendant fatty chain groups, containing silanol and/or hydroxyl groups. Such materials are useful for forming primer layers on polymeric substrates such as Polyurethane (PU). Oxidizing agents such as oxides of ce (iv) react with hydroxyl groups under mild reaction conditions within the undercoat layer to form hydroxyl groups to grow zwitterionic polymer brushes.

In another embodiment, a pair of peroxides and metal salts (e.g., Fe (II), as used in the Fenton reaction) are used in a redox polymerization reaction to create zwitterionic polymer brushes on polymers such as polyurethanes. Peroxide such as benzoyl peroxide, lauroyl peroxide, hydrogen peroxide or dicumyl peroxide is absorbed into a polymer such as polyurethane by immersing the polymer in a solution of the peroxide in an organic solvent for a predetermined time and drying. The peroxide-containing polymer is placed in the monomer solution. Redox polymerization is initiated by adding metal ions, such as metal ions fe (ii), such as fe (ii) chloride, fe (ii) sulfate, fe (ii) ammonium sulfate, or fe (ii) gluconate, to the monomer solution at room or elevated temperature.

For modifying the surface of articles and/or the surface of graft polymerization reactions, it has been found to be particularly advantageous to employ a hydrophobic-hydrophilic redox couple. For example, the hydrophobic material may be absorbed by the hydrophobic portion of the redox initiation system. "absorption" may include physical adsorption of the initiator to the surface and/or partial penetration of the initiator into the hydrophobic surface. Absorption may be assisted by the use of a solvent.

The absorbed surface is further modified by treatment with a hydrophilic monomer in the presence of the hydrophilic component of the redox pair. Grafting can be initiated at the hydrophobic-hydrophilic interface by a redox process. This method can also be used to coat polymer surfaces with complex geometries.

The use of hydrophobic-hydrophilic pairs has many advantages, including: due to the hydrophobic and hydrophilic nature of the initiator, diffusion of the redox initiator into the aqueous grafting solution and the matrix is limited. Uncontrolled diffusion of the redox couple can lead to polymerization of the solution and less surface functionalization. For example, if the pair is hydrophilic, polymerization will more readily occur in the monomer solution, thereby reducing the amount of polymer grafted from the substrate. Uncontrolled diffusion of the redox couple can also lead to undesired reactions from free radicals in the matrix.

Suitable initiator pairs include, but are not limited to: t-amyl perbenzoate, 4-azobis (4-cyanovaleric acid), 1 '-azobis (cyclohexanecarbonitrile), 2' -Azobisisobutyronitrile (AIBN), benzoyl peroxide, 2-bis (t-butylperoxy) butane, 1-bis (t-butylperoxy) cyclohexane, 2, 5-bis (t-butylperoxy) -2, 5-dimethylhexane, 2, 5-bis (t-butylperoxy) -2, 5-dimethyl-3-hexyne, bis (1- (t-butylperoxy) -1-methylethyl) benzene, 1-bis (t-butylperoxy) -3, 3, 5-trimethylcyclohexane, t-butylperoxy acetate, t-butylperoxy, Tert-butyl perbenzoate, tert-butyl isopropyl carbonate peroxide, cumene hydroperoxide, cyclohexanone peroxide, dicumyl peroxide, lauroyl peroxide, 2, 4-pentanedione peroxide 125, peracetic acid, potassium persulfate.

Other suitable redox systems include, but are not limited to: (1) peroxides combined with reducing agents, e.g. with Fe²⁺、Cr²⁺、V²⁺、Ti³⁺、Co²⁺、Cu⁺Or hydrogen peroxide of an amine combination, or peroxides of alkyl, aryl or acyl groups; transition metal ion complexes, such as copper (II) acetylacetonate and peroxide, zinc chloride and AIBN; (2) inorganic reducing agents and inorganic oxidizing agents, e.g. with inorganic oxidizing agents such as Fe²⁺、Ag⁺、Cu²⁺、Fe³⁺、ClO^3-、H₂O₂Combined of-O₃SOOSO₃，HSO₃ ^-、SO₃ ^2-、S₂O₃ ^2-、S₂O₅ ^2-(ii) a (3) Organic-inorganic redox couples, e.g. by Ce⁴⁺、V⁵⁺、Cr⁶⁺、Mn³⁺An oxygenated alcohol; (4) monomers that can act as components of a redox couple, such as thiosulfate and acrylamide, thiosulfate and methacrylic acid, and N, N-dimethylaniline and methyl methacrylate; and (5) a boryl-oxy system.

For substrates that require coating of both the interior and exterior surfaces, additional considerations are required for initiation of the polymerization reaction. Thermal initiators may be used, however, the elevated temperatures typically required can adversely affect the substrate material web. UV-based methods need to be designed such that UV can penetrate the material or can be applied within the lumen, for example from a fiber optic source. This can be achieved by selecting photoactive initiators that are unstable at UV wavelengths that are not absorbed by the matrix polymer. Generally, lower wavelength UV radiation is less absorbed and penetrates more easily than higher wavelength UV.

In contrast, redox chemicals typically do not require a direct route to a light source to initiate polymerization, since polymerization is not photolytically initiated, and thus facilitates coating of substrates, such as catheter lumens, having one or more surfaces that are difficult to expose to a UV source. In addition, redox polymerizations can generally be carried out at low temperatures, for example, below 60 ℃, below 55 ℃, below 50 ℃, below 45 ℃, below 40 ℃, below 35 ℃ or below 30 ℃.

The non-fouling polymeric material may be grafted from the surface using conventional procedures as described in the examples. In one embodiment, a solution containing 1% to 5% (w/w) urethane is formulated as follows: an appropriate weight of the urethane tablet is dissolved in an appropriate organic solvent such as tetrahydrofuran and the solution is diluted with a second solution such as methanol. The final methanol concentration is preferably between 10% and 90%, more preferably between 15% and 85%, most preferably 60%. One or more suitable initiator molecules, such as benzoyl peroxide or dicumyl peroxide, may be added to the polymer solution, typically at a concentration of about 0.25% to about 10%. However, concentrations below 0.25% and above 10% may also be used.

Any desired substrate may be exposed to the polymer/initiator solution one or more times until a suitable coating thickness and/or initiator surface concentration is obtained. In the case of multiple exposures of the substrate, the solvent is typically removed from the coated substrate between each exposure to the solvent, for example by evaporation. After the final exposure, the substrate was allowed to stand for at least 10 minutes to evaporate any residual solvent before being placed into the reaction mixture of the polymerization reaction.

The above process can be used to absorb high concentrations of initiator into or onto the substrate or primer layer. High initiator concentrations produce highly densely coated surfaces, which promotes the non-fouling activity of the composite. For example, a highly densely coated surface contains polymer chains with inter-polymer chain distances small enough to inhibit the penetration of contaminating molecules into the coating and thereby contaminate the substrate surface.

The above-described conventional procedures can be varied as necessary to accommodate different matrix materials, initiator systems, and/or monomer compositions.

C. Immobilization of bioactive agents on a substrate

In the graft-off process, the active agent is typically immobilized to the non-fouling material after the non-fouling material has grown from the surface.

The active agent may be co-immobilized with the non-fouling material in a side-by-side configuration. In the graft-from method, a tether may be grown from the surface, and the active agent is immobilized on the tether. Alternatively, the active agent may be immobilized directly on the surface without the use of a tether.

The active agent can be directly immobilized covalently or non-covalently to the substrate, the primer layer, the non-fouling material, or a combination thereof. In one embodiment, the active agent is covalently immobilized by reaction of one or more functional groups on the active agent with one or more functional groups on the substrate, primer layer, and/or non-fouling material. Covalent bonds can be formed by a variety of reaction mechanisms including, but not limited to, substitution, addition, and condensation reactions.

Method of use

The above materials may be used in the form of a medical device onto which a non-fouling material is applied as a coating. Suitable devices include, but are not limited to: surgical, medical or dental instruments, ophthalmic devices, wound treatment products (bandages, sutures, microscaffolds, bone cements, microparticles), appliances, implants, stents, suture materials, valves, pacemakers, stents, catheters, rods, implants, fracture fixation devices, pumps, tubes, wires, electrodes, contraceptives, gynecological hygiene products, endoscopes, wound dressings and other devices that are in contact with tissue, particularly human tissue.

A. Fibrous and particulate materials

In one embodiment, the non-fouling material is coated directly onto the fibrous material, incorporated into the fibrous material, or coated indirectly onto the fibrous material (e.g., on a different surface coating). These include wound dressings, bandages, gauze, tapes; a liner; sponges, including woven or non-woven sponges and those specifically designed for dental or ophthalmic surgery (see, e.g., U.S. patents 4,098,728, 4,211,227, 4,636,208, 5,180,375, and 6,711,879); paper or polymeric materials for use as surgical drapes; disposable diapers, tapes, bandages, feminine products, sutures; and other fibrous materials.

Fibrous materials may also be used in cell culture and tissue engineering devices. Bacterial and fungal infections are a major problem in eukaryotic cell culture, which provides a safe and effective means for minimizing or eliminating contamination of the culture, while allowing the desired cells to selectively adhere by the incorporation of directly attached proteins into the material.

Non-fouling agents are also readily associated with particles, including nanoparticles, microparticles, and millimeter beads, or formed into micelles, which can be used in a variety of applications, including cell culture and drug delivery as described above. The non-fouling, biocompatible polymeric micelles prevent protein denaturation, prevent activation of the immune response, and allow for more stealth delivery of the desired therapeutic agent.

B. Implanted or inserted materials

The non-fouling material may also be coated directly onto, or bonded to, a polymeric, metallic or ceramic substrate. Suitable devices include, but are not limited to: surgical, medical or dental instruments; a blood oxygenator; a pump; a tube; a wire; an electrode; a contraceptive device; feminine hygiene products; an endoscope; a graft; a support; a pacemaker; an implantable cardioverter-defibrillator; a cardiac resynchronization therapy apparatus; a ventricular assist device; a heart valve; catheters (including vascular, urinary catheterisation, neurological, peritoneal, interventional, etc.); a flow divider; wound drains; a dialysis membrane; an infusion port; a cochlear implant; an endotracheal intubation; a guide wire; a fluid collection bag; a sensor; wound management articles (dressings, bandages, sutures, microsupports, bone cement, microparticles); an ophthalmic device; orthopedic devices (hip implants, knee implants, spinal implants, screws, plates, rivets, rods, intramedullary nails, bone cements, artificial tendons, and other prosthetic or fracture repair devices); a dental implant; a breast implant; a penile implant; a maxillofacial implant; a cosmetic implant; a valve; an appliance; a working frame; a suture material; a needle; a hernia repair mesh; tension-free vaginal tape and vaginal sling; tissue regeneration or cell culture devices; or other devices used within or in contact with the body, or any portion of any of these devices. Preferably, the non-fouling materials herein do not significantly adversely affect the desired physical properties of the device, including but not limited to: elasticity, durability, kink resistance, abrasion resistance, thermal and electrical conductivity, tensile strength, hardness, burst pressure, and the like.

In one embodiment, the substrate is a catheter for insertion in a vessel, such as a central catheter for extrapolation (PICC), a Central Venous Catheter (CVC), or hemodialysis catheter, a venous valve, a punctual plug, and intraocular devices and implants.

In another embodiment, the substrate is made of medical grade polyurethane orFormed or formed of a material coated with medical grade polyurethane or Polycarbothane.

C. Paint, pigment, dipping liquid and spraying liquid

Non-fouling materials can also be added to paints and other coatings and filters to prevent mold, bacterial infection, and other applications where contamination prevention is desired, such as marine applications (boat hull coatings); a contact lens; a dental implant; an in vivo sensor coating; separation devices, such as membranes for microbial suspensions, biomolecule separations, protein fractionation, cell separation, wastewater treatment, bioreactors, and food processing.

Other applications include treating fibers, particles, and films for applications in textiles, additives, electrical/optical instruments, packaging materials, and colorants/inks.

Examples

Example 1 grafting of zwitterionic Polymer onto polyurethane with benzophenone UV initiator

Step 1: and (5) soaking the benzophenone. The polyurethane sample was placed in a 1L VWR or Pyrex bottle. To the bottle was added 160mL of a 10% (w/v) solution of benzophenone in acetone. After the addition of the stir bar, the bottle was capped, covered with aluminum foil to prevent light, and stirred overnight. The benzophenone solution was decanted from the polyurethane sample, 150mL of acetone was added, covered with aluminum foil, and the polyurethane sample was stirred for 30 minutes. The sample was filtered with a large buchner funnel and washed with acetone. The samples were placed in glass Petri dishes, dried with a stream of nitrogen, and placed on aluminum foil overnight in the dark.

Step 2: and (4) UV grafting. The bottom of the quartz glass tube was blocked with a rubber septum and sealed with parafilm. Teflon tape was wrapped across the top of the tube to ensure a tight seal of the top septum. The benzophenone soaked polyurethane sample was placed in a tube, the top of which was blocked with a rubber septum and sealed with parafilm. After blowing a 10% (w/v) SBMA solution in water with argon and all quartz reaction tubes for 35 minutes, the monomer solution was transferred to each reaction tube and the ends were secured with parafilm. Tapping allowed the foam to escape to rest on top of the solution. The tube was placed vertically in a UV reactor and irradiated with rotation for 6 hours. After removing the tubes from the reactor, each polyurethane sample was washed with hot water, shaken overnight in 1 XPBS, and stored in 4 ℃ 1 XPBS in plastic culture tubes. Carboxybetaine coatings can be built in a similar way using monomers such as CBMA instead of SBMA.

Each SBMA sample generated on a 10French polyurethane rod was evaluated for antithrombotic performance by flow cycling them for 2 hours exposed to freshly collected bovine blood with radiolabeled platelets. Both SBMA and CBMA samples prepared in this UV method showed approximately 80% reduction in platelet adsorption and substantial visible reduction in thrombus.

Example 2 grafting of zwitterionic Polymer onto undercoated polyurethane and Ce (IV) redox polymerization

Synthesis of copolymer

50mL of dry methanol was added to a 250mL dry flask along with 4mL of lauryl methacrylate and 4mL of 2-hydroxyethyl methacrylate. After purging with nitrogen for 5 minutes, 0.3mL of 3- (trimethoxysilyl) propyl methacrylate was added and degassing was continued. 0.2g of Azobisisobutyronitrile (AIBN) was added and stirred at 60 ℃ for 18 hours in an inert atmosphere to start the polymerization. The reaction mixture was purified by dialysis separation with anhydrous methanol (molecular weight cut-off 2000) to obtain a copolymer solution (undercoat layer solution).

Primer coating

A polyurethane substrate, such as a 10French polyurethane rod, is immersed in a 0.5% solution of the primer in methanol for 3 minutes at ambient conditions, removed and dried at 60 ℃ for 1 hour. The above dipping and drying steps were repeated 4 times, and then the sample was dried at 60 ℃ for 18 hours. Then washed first with 1 × PBS for 18 hours, then with DI water and then air dried.

Ce (IV) mediated graft polymerization

The primed samples were added to the flask along with a 10% aqueous solution of SBMA containing 1mg/mL ammonium cerium (IV) sulfate, purged with nitrogen for 15 minutes. The reaction was then stirred at 45 ℃ for 2 hours. Samples were removed and the adsorbed homopolymer washed away with PBS. The treated sample exhibited a reduction in fibrinogen adsorption of 83% by ELISA.

Example 3 grafting of zwitterionic Polymer to polyurethane by dicumyl peroxide-Fe (II) gluconate Redox polymerization

Absorption of dicumyl peroxide

A 10French polyurethane rod was immersed in a solution of 10% dicumyl peroxide in acetone or methanol for 2 hours, dried with a stream of air and kept in air for 18 hours.

Redox polymerization

A 10.5% SBMA aqueous solution and dicumyl oxide treated polyurethane rod were placed in a magnetically stirred flask, then purged with argon for 10 minutes, after which 100mM fe (ii) gluconate solution was added. The final solutions of SBMA and Fe (II) gluconate were 10% (w/w) and 5mM, respectively. Purging with argon was continued for another 20 minutes. The reaction was then carried out at 60 ℃ for 5 hours. The sample was then removed and washed overnight with 1 × PBS. The treated samples exhibited up to 90% reduction in fibrinogen adsorption by ELISA.

To evaluate the non-fouling activity of the matrix with inner lumen, a 14French polyurethane double d inner lumen tube was coated as in example 3. Using the analytical method described above, the treated samples exhibited reduced fibrinogen adsorption of up to 90%.

Example 4 protein adsorption and biofilm formation of Redox and UV SBMA coated polyurethane rods

24 hour colony assay method

The redox SBMA prepared in example 3, UV SBMA prepared in example 1, and control Carbothane rods were incubated with 50% fetal bovine serum for 18 hours. The samples were then treated with Staphylococcus aureus ATCC 25923 to 1-3X 10 in 1% TSB⁵CFU/mL initial plankton concentration, at 37 degrees C stirring culture 24 hours. After 24 hours, the patient is treated with ultrasoundBiofilm accumulated on the material was removed by physical methods and the total amount of bacterial cells was measured by dilution plating. Further plankton concentrations were monitored at the end of the experiment to ensure that there were no toxic leachable compounds that could distort the assay. After incubating the plate at 37 ℃ for 24 hours, the number of colonies was counted and the number of viable cells present on each sample was determined.

Each experiment was performed in triplicate with four samples of each material.

Colonies from the redox SBMA sample (n-44) demonstrated an average 1.96 log (SD 0.57log, p < 0.001) reduction and the UV SBMA sample demonstrated an average 2.34 log (SD 0.22log, p < 0.001) reduction (n-24) relative to the control.

Example 5 antithrombotic Activity of carboxybetaine-coated rods

Model of thrombosis in vivo

The long-term in vivo performance of UV-based carboxybetaine modification prepared as described in example 1 was demonstrated in 7-day cephalic vein implantation of coated Tecoflex rods in sheep. Briefly, 4fr.x 15cm modified or unmodified by CBThe test piece constituted by the rod was inserted into the cephalic vein of a two-year old, savory ram. After 7 days, the sheep were anesthetized, peripheral blood samples were taken, the cephalic vein was ligated and incised, and the implanted article was held in the vein during removal. The vein is then cut axially and carefully opened without disturbing the thrombus on the implanted rod. The total thrombus mass was assessed on both coated and uncoated articles. Each animal received one coated and uncoated device to control animal-to-animal variability. A 72% reduction in thrombus weight was found relative to the Tecoflex control placed in the opposite vein of the same animal (see fig. 1), and the reduction was clearly visible. These data demonstrate the ability of an anti-adhesion coating to prevent thrombosis and the long-term stability of such coatingsThe potential for activity is maintained.

EXAMPLE 6 zwitterionic homopolymers on polyurethane Using dicumyl peroxide redox polymerization

Tecoflex SG-93A (2.5g) was dissolved in refluxing tetrahydrofuran with vigorous stirring. The solution was cooled to room temperature and diluted with methanol. The final solution concentration was 1% Tecoflex SG-93A, 40% tetrahydrofuran and 60% methanol. To an aliquot (25g) of this polymer solution, dicumyl peroxide (2.5g) was added and the mixture was stirred until all dicumyl peroxide had dissolved.

Carbothane extrudates (14french, 11cm long, bis D) were dipped into the initiator-polymer solution. The samples were dipped 1,2, 4 or 8 times. Between each impregnation, the solvent was evaporated from the substrate for 1 minute. After the final impregnation, all samples were left to stand at room temperature for 3 hours to remove any residual solvent. After evaporation of the solvent, 0.5cm was cut from each end of the sample, which was then cut in half. A5.0 cm sample was placed into a 40mL amber glass vial and sealed with a septum.

A separate solution of SBMA (91.2g in 432mL deionized water) and Fe (II) gluconate (1.02g in 12mL deionized water) was deoxygenated by bubbling argon through it with stirring for 30 minutes. When these solutions were deoxygenated, amber glass vials containing 5cm of extrudate were flushed with argon for 30 minutes.

To each flask was added SBMA solution (36mL) using syringe followed by fe (ii) gluconate solution (1mL) using syringe. The vial was heated to 37 ℃ on an Anthill reaction shaker and the reaction was allowed to shake at 680RPM for 24 hours.

After the reaction, all samples were taken out of the reaction vial and washed three times with 1X Phosphate Buffered Saline (PBS). The washed samples were soaked in 1 × PBS for 2 days and then analyzed by the radiolabeled fibrinogen analysis method.

Claims (61)

1. A composition comprising a substrate, optionally comprising an undercoating layer immobilized on the substrate, having covalently attached to the substrate or the undercoating layer a non-fouling polymeric material, wherein the polymeric material is grafted from the substrate or the undercoating layer, when present, wherein the composition comprises a polymerization initiator absorbed into the substrate or the undercoating layer, when present.

2. The composite of claim 1, wherein the substrate is selected from the group consisting of metallic materials, ceramics, polymers, woven materials, non-woven materials, silicon, and combinations thereof.

3. The composite of claim 2, wherein the metallic material is selected from the group consisting of titanium and alloys thereof, stainless steel, tantalum, palladium, zirconium, niobium, molybdenum, nickel-chromium alloys, cobalt or alloys thereof, and combinations thereof.

4. The composite of claim 2, wherein the ceramic is selected from the group consisting of oxides, carbides or nitrides of transition metal elements or non-metal elements.

5. The composite of claim 2, wherein the polymer is selected from the group consisting of polystyrene and substituted polystyrenes, polyurethanes, polyacrylates and polymethacrylates, polyacrylamides and polymethacrylamides, polyesters, polysiloxanes, polyethers, polycarbonates, polyfluorocarbons, PEEK, epoxies, polyamides and copolymers thereof, phenolics, polyolefins, polysulfones, polyacrylonitriles, polysaccharides, and combinations thereof.

6. The composite of claim 2, wherein the polymer is selected from the group consisting of polyorthoesters, teflon, PTFE, nylon, and polyalkenes.

7. The composite of claim 5, wherein the polymer is a polyurethane or a polycarbonate-based polyurethane.

8. The composite of claim 1, wherein the substrate is not gold or glass.

9. The composition of any one of claims 1-8, wherein the substrate surface comprises a primer coating to form a surface having a uniform chemical composition.

10. The composite of claim 9, wherein the primer layer is a polyurethane.

11. The composite of claim 1, wherein the substrate is an oxide treated substrate.

12. The composition of claim 1, wherein the matrix is thiol-free.

13. The composition of claim 1, wherein the non-fouling polymeric material is a zwitterionic polymer.

14. The composition of claim 13, wherein the zwitterionic polymer is a homopolymer or copolymer comprising one or more monomers having the following structural formula:

wherein B is selected from the following groups:

wherein R is selected from hydrogen, substituted alkyl or unsubstituted alkyl;

e is selected from the group consisting of substituted alkyl, unsubstituted alkyl, - (CH)₂)_yC (O) O-and- (CH)₂)_yC(O)NR²；

Y is an integer of 0 to 12;

l is absent or is a linear or branched alkyl group, optionally containing one or more oxygen atoms;

ZI is a zwitterionic group; and

x is an integer of 3 to 1000.

15. The complex of claim 14, wherein ZI is selected from the group consisting of:

wherein R is₃And R₄Independently selected from hydrogen and substituted or unsubstituted alkyl;

R₅selected from substituted or unsubstituted alkyl, phenyl and polyether groups; and

m is an integer from 1 to 7.

16. The complex of claim 14 or 15, wherein x is 10 to 500.

17. The composition of claim 15, wherein the zwitterionic polymer is a homopolymer of sulfobetaine methacrylate (SBMA) or sulfobetaine acrylamide.

18. The composition of claim 15, wherein the zwitterionic polymer is a copolymer comprising sulfobetaine methacrylate (SBMA) or sulfobetaine acrylamide.

19. The composition of claim 13, wherein the zwitterionic polymer has the structure:

wherein B is₁And B₂Independently selected from:

r is selected from hydrogen and substituted or unsubstituted alkyl;

e is selected from substituted or unsubstituted alkenyl, - (CH)₂)_pC (O) O-, and- (CH)₂)_pC(O)NR²-, where p is an integer of 0 to 12,

R²selected from hydrogen and substituted or unsubstituted alkyl;

l is a linear or branched alkenyl group, optionally containing one or more oxygen atoms;

P₁is a positively charged group;

P₂is a negatively charged group;

m is an integer of 3 to 1000; and

n is an integer from 3 to 1000.

20. The composition of claim 13, wherein the polymer comprises one or more monomers selected from the group consisting of:

wherein R is selected from substituted or unsubstituted alkyl;

L₁、L₂and L₃Independently a straight or branched chain alkenyl group, optionally containing one or more oxygen atoms; and

n is an integer from 3 to 1000; and

n1 is a negatively charged group.

21. The complex of claim 19 or 20, wherein the negatively charged group is selected from the group consisting of carboxylate groups, -SO₃ ^-、-OSO₃ ^-、-PO₃ ^-and-OPO₃ ^-A group.

22. The complex of claim 19, wherein the positively charged group is a quaternary nitrogen or cationic phosphorus containing group.

23. The complex of any one of claims 19 or 20, wherein x, m, and n are 10 to 500.

24. The composition of claim 1, wherein the non-fouling polymeric material is a non-zwitterionic polymer selected from the group consisting of polyethers, polysaccharides, polyvinylpyrrolidone, hydroxyethyl methacrylate, acrylonitrile-acrylamide copolymers, heparin.

25. The composition of claim 24, wherein the non-zwitterionic polymer is selected from mixed charged polymers.

26. The composition of claim 24, wherein the non-zwitterionic polymer is selected from the group consisting of polymers containing hydrogen bond accepting groups.

27. The composite of claim 1, wherein the polymeric material is formed by UV initiated free radical polymerization.

28. The composite of claim 1, wherein the polymeric material is formed by a redox-initiated free radical polymerization.

29. The composition of claim 28, wherein the non-fouling polymeric material is polymerized from groups present in the substrate and/or the primer layer.

30. The composition of claim 28, wherein the group is formed from a redox pair comprising a peroxide and a metal salt.

31. The composite of claim 30, wherein the peroxide is absorbed into the matrix.

32. The composition of claim 30, wherein the peroxide is dicumyl peroxide and the metal salt is fe (ii) gluconate.

33. The composition of claim 1, wherein the non-fouling polymeric material is terminally attached to the substrate to form a brush-like structure.

34. The composition of claim 1, wherein the non-fouling polymeric material is tethered from the substrate or the primer layer.

35. The composition of claim 1, wherein the non-fouling polymeric material, substrate, undercoating layer, or combination thereof has immobilized thereon one or more bioactive agents.

36. The composition of claim 35, wherein the one or more bioactive agents are immobilized covalently or non-covalently to the non-fouling material, substrate, undercoating layer, or combinations thereof.

37. The composition of claim 35 or 36, wherein the one or more bioactive agents are immobilized to the non-fouling material, the substrate, the undercoating layer, or a combination thereof, by a tether.

38. The complex of claim 1, wherein the complex has more than 50% less contamination after storage in Phosphate Buffered Saline (PBS), culture medium, serum, or in vivo at 37 ℃ for at least 7 days compared to the uncoated substrate.

39. The complex of claim 1, wherein the complex is biocompatible.

40. The complex of claim 39, wherein the complex is nonhemolytic and non-cytotoxic.

41. The complex of claim 1, wherein the complex is antibacterial.

42. The complex of claim 1, wherein the complex is antithrombotic.

43. The complex of claim 1, wherein the complex retains at least 25% of its original material properties in PBS, culture medium, serum, or in vivo for a period of 7 days.

44. The composite of claim 1, wherein the composite is in the form of a medical device.

45. The composite of claim 44, wherein the medical device is selected from the group consisting of: fibers; surgical, medical or dental instruments; a drug delivery device; a tube; a graft; a flow divider; an implantable sensor; appliances or other medical devices for use within or in contact with the body.

46. The composite of claim 44, wherein the medical device is selected from the group consisting of: a blood oxygenator; a ventilator; a pump; a wire; an electrode; a contraceptive device; feminine hygiene products; an endoscope; a support; a stent graft; a pacemaker; an implantable cardioverter-defibrillator; a cardiac resynchronization therapy apparatus; a cardiovascular device lead; ventricular assist devices and drivetrain; a vena cava filter; an intravascular coil; a conduit; conduit connections and valves; intravenous delivery lines and manifolds; wound drains; a dialysis membrane; an infusion port; a cochlear implant; an endotracheal intubation; a tracheostomy tube; a ventilation breathing tube and a circuit; a guide wire; a fluid collection bag; drug delivery bags and tubes; an ophthalmic device; an orthopedic device; a dental implant; a periodontal implant; a breast implant; a penile implant; a maxillofacial implant; a cosmetic implant; a valve; a working frame; a suture material; a needle; a hernia repair mesh; tension-free vaginal tape and vaginal sling; a neurological repair device; tissue regeneration and cell culture devices.

47. The composite of claim 44 wherein the medical device is a heart valve.

48. The composite of claim 45, wherein the device comprises a lumen, void, porous structure, or a combination thereof.

49. The combination of claim 48, wherein the device is a pulse-tube inserted catheter selected from the group consisting of an external central catheter (PICC), a Central Venous Catheter (CVC), and a hemodialysis catheter.

50. The composite of claim 1, wherein the difference in tensile strength, modulus, device size, or a combination thereof is within 20% of the tensile strength, modulus, device size, or a combination thereof of the uncoated substrate.

51. A method of making the composite of any of claims 1-50, comprising grafting a non-fouling polymeric material from within and/or on the surface of the substrate, the primer layer, or both.

52. The method of claim 51, wherein one or more free radical initiators are used to graft the non-fouling polymeric material from within and/or on the surface of the substrate, the primer coating, or both.

53. The method of claim 52, wherein the one or more initiators are Ultraviolet (UV) initiators.

54. The method of claim 52, wherein the one or more initiators is a redox couple.

55. The method of claim 53 or 54, wherein the one or more free radical initiators are imbibed into the substrate, the primer layer, or a combination thereof.

56. The method of claim 54, wherein the redox initiator comprises a hydrophobic-hydrophilic redox initiator pair.

57. The method of claim 56, wherein the redox initiator system comprises a peroxide and a metal salt.

58. The method of claim 57, wherein the peroxide is dicumyl peroxide and the metal salt is Fe (II) gluconate.

59. The process of claim 51 wherein the graft polymerization reaction is carried out without the use of light.

60. The method of claim 51, wherein the substrate, primer layer, or combination thereof is not treated with plasma or ozone to generate free radicals to initiate polymerization.

61. The process of claim 51, wherein the graft-from polymerization is carried out in the presence of one or more oxygen scavengers.