ES2348795T3 - ANTIMICROBIAL MEDICAL PRODUCT, PROCEDURE FOR MANUFACTURING AND USE. - Google Patents

Abstract

Medical product provided with an antimicrobial finish of a complex material based on metal nanoparticles and macromolecules, the macromolecules being made up of at least one polyamino acid, characterized by the fact that the polyamino acid is modified to be amphiphilic by a substance and the substance is a fatty acid or a derivative of fatty acid.

Description

Antimicrobial medical product, procedure for its manufacture and use.

The invention relates to a medical product with an antimicrobial finish, a procedure for its manufacture such as the use of the antimicrobial finish as a biocide in case of medical products.

The demands regarding hygienic standards that increase permanently in recent years lead particularly in the medical sector to a need considerable in antimicrobial materials. Since the usual consumables, for example wood, ceramics, plastic, glass or steel themselves have no characteristics antimicrobial, should be made antimicrobial.

A powerful approach to this purpose is based in the so-called active contact systems, providing the materials of an antimicrobial modification, so that the microorganisms in case of contact with the modified material, without release an antimicrobial bond only limitedly present contrary to equally common release systems. The active contact systems frequently consist of polymers grafted antimicrobials, particularly polycationic polymers with ammonium, pyridinium, biguanidine, sulfonium or phosphonium However the application of polymers on the respective material rarely requires modifications expensive surfaces. This is known for example from the US 2004/0171978 A1 which for the immobilization of polylysine on a polymer surface is first made a sulfonization of the surface. In addition, some systems in contact active are only limitedly operational for medical applications to cause of the toxic properties of some polymers antimicrobials

WO2004 / 056404 discloses medical objects with antimicrobial coatings that may particularly comprise poly-lysine.

WO03 / 072143 discloses a compound Biocompatible for the administration of an active substance. He compound in this case presents a support with a link domain for a metal, a metal ion complexed to a bond domain as well As an active substance. How polymeric supports are related among other things various polyamino acids.

WO2004 / 101011 discloses a product biocidal medical technician containing macromolecules branched amphiphiles, metal nanoparticles, procedures for Its manufacture and application.

WO2004 / 085998 discloses a theory three-dimensional constructivist based on a matrix of polymer and chemically functionalized nanoparticles. The nanoparticles are coated in this case with a layer monomolecular that contains biological information.

In the medical and clinical sector there are however high requirements to the biocompatibility of materials, particularly those that are intended for use surgical. Frequently, therefore, only one small space between antimicrobial activity and biocompatibility of the respective material.

The objective of the present invention is therefore both provide medical products with high activity antimicrobial on the one hand and high biocompatibility on the other part.

This objective is solved by a product doctor with an antimicrobial or biocidal finish of a material complex of metal nanoparticles and macromolecules, being constituted the macromolecules at least partially by a polyamino acid, characterized by the fact that the polyamino acid is modified to be amphiphilic by a substance and the substance It is a fatty acid or a derivative of fatty acid.

Under an antimicrobial or biocide finish in the meaning of the present invention is to be understood as a preparation that prevents cell growth and / or cell proliferation of microorganisms, particularly germs (microorganisms harmful) and / or causes the elimination of colonies of microorganisms existing, particularly of germ colonies.

According to an embodiment of the medical product, the antimicrobial finish is provided at least on a part of the product surface, particularly in the form of a coating. The antimicrobial finish is preferably present at least on a part of the product surface, particularly in the form of a coating. The antimicrobial finish preferably extends over the total surface of the medical product. The medical product finished in this manner is advantageously characterized by the fact that it consists of a sufficiently stable adhesive bond between the finish and the surface of the product material, so as to prevent, for example, a detachment, particularly a rub or wash of the finish. of the coated product and therefore a long-term and effective prevention of the medical product against microbial colonization is guaranteed, particularly once the application has been carried out. The adhesive bond may be based on electrostatic attractive forces, hydrogen bonds and / or lipophilic interactions, particularly on the forces of
van der Waals.

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Additionally or alternatively to the form of embodiment just described may be provided according to the invention that the complex material is within the product. This can be especially advantageous when the material of the medical product is a polymer or other material, whose manufacturing procedure allows the introduction of the material complex inside the product. This way you can achieve a uniformly distributed antimicrobial activity of the product doctor.

In another embodiment, each nanoparticle metal is surrounded by at least one polyamino acid, being surrounded by each metal nanoparticle preferably by all Wrapped sides by at least one polyamino acid. Preferably the polar part, particularly charged, of the polyamino acid is oriented towards metal nanoparticles and it allows coordinative or donative links with the nanoparticles of metal by heteroatoms or clusters of heteroatoms located in the polar part, for example the nitrogen atoms and / or of oxygen. According to the invention, the metal nanoparticles can be polarized in this way partially positive.

The polyamino acid can be particularly a homo-polyamino acid or hetero-polyamino acid, being especially preferred a homo-polyamino acid. Polyamino acid it can consist of existing and / or synthetic natural amino acids, existing natural amino acids being preferred, particularly aminocarbonic acids, especially acids aminocarbons having an L configuration. Preferably, Amino acids are at least trifunctional amino acids. Under a trifunctional amino acid within the meaning of the present invention has to understood as an amino acid that presents, in addition to the group carboxyl and amino group, another organic functional group, particularly another hydroxyl, thiol, guanidino or amino group, preferably another amino group. Preferably the polyamino acid It contains at least one amino acid that carries a basic group, acid and / or sulphurous In the sulphurous group it can be particularly thiol and / or thioether groups. With special preference, the polyamino acid contains at least one amino acid in the group comprising cysteine, methionine, tryptophan, histidine, arginine, lysine, ornithine, aspartic acid, glutamic acid and its derivatives.

Advantageously the polyamino acid has a linear structure The linear structure allows an arrangement dense around the metal nanoparticles to stabilize, in the which stabilizes the arrangement particularly by forces electrostatics, hydrogen bridge links and / or interactions lipophilic, particularly van der Waals forces.

In another preferred embodiment of the invention, the polyamino acid has a branched structure, preferably a hyperbranched structure. The structure branched particularly allows a compact arrangement around the metal nanoparticles to stabilize, so particularly the stabilization of the nanoparticles is increased of metal. In addition, the branched structure of polyamine acid it causes advantageously a reduced fragility of the material product complex according to the invention. Therefore, the branched polyamino acids increase in a preferred manner the film-forming characteristics of the complex material.

According to a preferred embodiment of the medical product, the polyamino acid is polylysine, particularly a poly-α-lysine (poly-alpha-lysine) and / or a poly-lysine (poly-epsilon-lysine). Both the poly-α-lysine as well as the poly-e-lysine have properties antimicrobial, being the poly- lysine plus biocompatible contrary to poly-α-lysine and therefore especially preferred. The product polylysine according to the invention particularly presents a degree of polymerization (DP, degree of polymerization) from 10 to 15, particularly 12 to 14, preferably approx. 13. The molecular weight of polylysine preferably it is between 3000 g / mol and 6000 g / mol, particularly between 4000 g / mol and 5000 g / mol.

According to a preferred embodiment of the medical product, the polyamino acid is an amphiphilic modification by a substance, particularly by that with at least one aliphatic residue. Such a modification may be especially preferred, to increase the stabilization of the metal nanoparticles and the reciprocal shielding of the polyamino acids that coordinate the nanoparticles. In this way the creation of larger nanoparticles can be avoided, particularly in the form of aggregates. In addition, the formation of polyamino acid aggregates can be avoided. After modification of the polyamino acid, the aliphatic residue is preferably oriented particularly towards the outside of the metal nanoparticles. The structure obtained in this way from the metal nanoparticles and polyamino acids modified to be amphiphilic can be called a core-shell structure (core-shell-particles), where the polyamino acids directly surrounding the metal nanoparticles represent the nucleus and the substance It represents the shell of the structure. Under amphipility within the meaning of the present invention, the property of a bond having both hydrophilic and lipophilic properties due to its molecular structure is to be understood. A complex with a core-shell structure is particularly known from DE 103 23 597 A1 which consists essentially of polyethyleneimine modified to be
amphifile

The aliphatic residue of the substance presents preferably 6 to 22, in particular 12 to 18, preferably 16 and / or 18 carbon atoms. The aliphatic residue can be a alkyl, alkenyl substituent and / or a substituent of alkynyl, substituents of alkyl, particularly unbranched. Thus, the substituents of alkyl, particularly chain alkyl substituents long and preferably unbranched, allow in the shell area of the core-shell structure a closer or more compact adhesion of the alkyl chains the to each other, which is essentially due to interactions lipophilic, particularly to van der Waals forces.

The substance is preferably at least one biocompatible substance, in particular a fatty acid or a derivative of fatty acid, preferably palmitic and / or stearic acid. For the amphiphilic modification of the polyamino acid, it may be preferred that the fatty acid is present as a derivative of fatty acid, particularly in an activated form, preferably as chloride of fatty acid. Furthermore, according to the invention it may be preferred that the substance is present as a mixture of different substances, particularly of different fatty acids or acid derivatives fatty. Thus, a mixture of palmitic acid and stearic acid chloride, for example a mixture of 60 parts by weight of stearic acid chloride and 40 parts by weight of palmitic acid chloride, due to its more price Low compared to pure fatty acid chlorides.

According to an embodiment especially Preferred product according to the invention, the amphiphilic modification of the polyamino acid by the substance is based on covalent bonds, particularly in amide links. The amide links are preferably constituted by the free amino groups of the polyamino acid and by acyl groups of the substance. In the case of poly-e-lysine, in the groups free amino is about α-amino groups of polyamino acid. Starting from pure lysine monomers, the part of free amino groups after the preparation of Unmodified polyamino acid is usually approx. fifty%. He medical product is preferably characterized by the fact that the proportion of free amino groups of the polyamino acid after the amphiphilic modification of the polyamino acid is between 0.5 and less than 50%, particularly between 10 and 40%, particularly between 20 and 40%, preferably it is approx. 37%, with respect to the total amount originating from the amino groups of the monomers of amino acid used for the preparation of polyamino acid, preferably lysine monomers.

According to another embodiment especially preferred of the medical product, the substance is linked with the polyamino acid by means of a crosslinking component, in particular a polyfunctional carboxylic acid, preferably an acid citric. The cross bond is preferably based on the formation of covalent bonds, particularly amide bonds, being formed amide bonds by condensation between groups amino of the polyamino acid and acid groups, particularly the carboxyl groups, of the crosslinking component. The cross link of polyamino acid is especially advantageous, since in this way there are closed core-shell structures after amphiphilic modification of crosslinked polyamino acid and groups functional, in particular the carboxyl groups of the component crosslinker, increase the number of possible coordination points for the metal nanoparticles in the polymer. In this way, complexation properties can be improved for metal nanoparticles In addition, the properties of the biocidal complex material determined by the bond crossed, in particular its film-forming properties.

The proportion in free amino groups after cross-linking of polyamino acid, particularly with acid citric, preferably is between 25 and less than 50%, in particular between 30 and 45%, preferably between 35 and 43%, with with respect to the total original amount of the amino groups of the amino acid monomers used for the preparation of polyamino acid, preferably lysine monomers. A polylysine, in particular the cross-linked poly-lysine with 5% molar citric acid, it preferably has a proportion in free amino groups of approx. 43% compared to lysine monomers used, and a polylysine, in particular the cross-linked poly-lysine With 10% molar citric acid, it has a proportion in amino groups free of approx. 35% for lysine monomers employees, with respect to the total origin of the groups amino of the lysine monomers used for the preparation of polyamino acid.

In another preferred embodiment, the proportion in free amino groups after modification cross-linked polyamino acid amphiphile is between 15 and 35%, particularly between 25 and 35%, preferably is approx. 30%, with respect to the total amount originating from the amino groups of the amino acid monomers, preferably the monomers of lysine used for the preparation of polyamino acid. In a Especially preferred embodiment, a polylysine, particularly a poly-lysine, crosslinked with 5% molar citric acid with respect to lysine monomers used, presented after modification amphipilate a proportion in free amine groups of approx. 32% and a polylysine, in particular a cross-linked poly-lysine with 10% molar citric acid with respect to monomers of lysine employees, presents after amphiphilic modification a proportion in free amino groups of approx. 26%, with respect to the total amount originating from the amino groups of the monomers of lysine used for the preparation of polyamino acid.

In the case of metal nanoparticles according to the invention can be about gold, silver, nanoparticles of copper or zinc, nanoparticles being especially preferred silver. With advantage, metal nanoparticles have a diameter from 0.5 to 20 nm, in particular from 1 to 20 nm, preferably from 1 to 14 nm.

The silver nanoparticles that are stabilized by uncrosslinked polyamino acids and modified to be amphiphilic by a mixture of palmitic acid chloride and stearic, particularly polylysine, preferably the poly-lysine, have preferably a diameter of approx. 6 nm, particularly after of reduction with ascorbic acid. In some cases however it may be preferred that the silver nanoparticles have a smaller diameter, in particular approx. 4 nm This is possible for example by a reduction with the reducer LiBHEt_ {3}.

According to another preferred embodiment, the silver nanoparticles that are stabilized by polyamino acids crosslinked, particularly crosslinked by citric acid, and modified to be amphiphilic with a mixture of acid chloride palmitic and stearic, particularly polylysine, preferably the poly-lysine, have a diameter of approx. 10 nm (5 mol% citric acid with respect to lysine monomers used) or approx. 8 nm (10 mol% of citric acid with respect to the lysine monomers used). This can be achieved for example by acid reduction ascorbic

In some cases it may be desirable that metal nanoparticles, in particular silver nanoparticles, of the complex material have a diameter of the order of 2.5 to 3.5 nm. This for example can be achieved by using polylysine, preferably the poly-lysine. The Polylysine is preferably crosslinked with citric acid and particularly modified to be amphiphilic by a mixture of palmitic and stearic acid chloride. In this way, the Metal nanoparticles can have a diameter of approx. 3.1 nm in the case of a polylysine stabilization that is crosslinked with 5% molar citric acid with respect to the monomers of Lysine employees. In the case of using polylysine which is crosslinked with 10% molar citric acid with respect to lysine monomers used, metal nanoparticles can have a diameter of approx. 2.7 nm.

It can also be provided according to the invention. that the medical product be a temporary or lasting implant for the human or animal body In this case, finished implants antimicrobial are preferably joint implants, stents, screws, nails and plates. Implants can consist of metal or metal alloys. Like other materials for implants, the Synthetic materials. Implants can be used for example for fracture repair. The implants can also be meshes, preferably meshes for hernias. Like other implants preferred prostheses are particularly considered vascular, membranes as well as sheets, for example for adhesion prophylaxis. In addition, according to the invention it is preferred that the implants are incontinence bands as well as generally textile implants How textile implants come into consideration particularly fabrics, knitwear, knitted fabrics, fiber and fleece fabrics. The biocidal finish of these implants allows to introduce these also in infected body regions acute or in danger of infection, since the implants themselves by their finish they have an antimicrobial effect and in this way contribute to a reduction of an existing infection or potential.

In another embodiment, the products doctors are medical instruments, particularly scissors surgical, pliers and staples as well as catheters or probes and others instruments, particularly for minimal invasive interventions. In this regard, the aforementioned adhesive bond of the finish antimicrobial with the surface of the medical product is of a particular advantage, since the now called instruments doctors for example are exposed to mechanical fatigue especially high, particularly by rubbing and rubbing. The Adhesion of the antimicrobial finish with the product surface it is particularly achieved through lipophilic interactions, preferably van der Waals forces, of aliphatic remains long-chain substance oriented particularly far from The metal nanoparticles.

Medical products according to this invention can also be products such as tubes Flexible drainage, suture materials or wound dressings. The material of the medical product according to another embodiment Preferred is a metal or a metal alloy, particularly of titanium, stainless steel, magnesium, tantalum or an alloy of that, magnesium and / or tantalum being especially preferred due to its biocompatibility and resorbability.

In another embodiment, the material of the medical product is a non-absorbable polymer or a polymer at less partially reabsorbable. Thus, the non-absorbable polymer it can be a polyolefin, in particular polyethylene and / or polypropylene, a polyester, particularly terephthalate of polyethylene and / or polybutylene terephthalate, a polyamide, particularly polyamide 6 or polyamide 6.6, or a natural fiber, particularly silk or linen. The polymer at least partially absorbable is preferably a completely polymer resorbable The resorbable polymer can be particularly a polymer based on monomers such as lactide, glycolide, trimethylene carbonate, para-dioxanone and / or ε-caprolactone, preferably in form of a copolymer and / or terpolymer. Corresponding to another form of embodiment, a medical product, whose material is not reabsorbable, it can be coated with a polymer at least partially absorbable, preferably completely absorbable, particularly with one of the polymers now related, for influence or regulate the access duration of liquids, particularly body fluids, with respect to antimicrobial finish.

In another embodiment, the material of the Medical product is a ceramic material. With advantage it can be treated of a resorbable ceramic material, particularly of hydroxyapatite or tricalcium phosphate.

According to another embodiment, the product It has pores, preferably interconnecting pores. This can be especially advantageous, since in this way it is available an enlarged surface for the antimicrobial finish. By consequently, a larger amount of the biocidal complex material or antimicrobial can be applied on and, in the case of a interconnecting pore system, also within the product to finish.

The product is advantageously sterilized and particularly exists in sterilized form. Sterilization methods include all methods known to the skilled person, particularly irradiation, steam sterilization, ethylene oxide fumigation and plasma sterilization, which preferably do not impair the chemical structure and / or antimicrobial properties of the particularly present complex material in the form of a core-shell structure. The medical product according to the invention in use is preferably present in the form
sterile.

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The object of the invention further relates to a procedure for the preparation of a medical product, applying the complex material, particularly in the form of a solution, from the outside on the unfinished product. In the solution, the metal nanoparticles, in particular silver nanoparticles, they are preferably present in stabilized form according to one of the above embodiments. The preparation of a solution of this type is preferably performed starting from polyamino acids modified to be amphiphilic and particularly crosslinked. The core-shell polymers manufactured in this way are dissolved in an organic solvent and charged by adding a metal salt with the corresponding metal ion. The solution repaired in this way contains metal ions stabilized by polyamino acids modified to be amphiphilic and particularly crosslinked and is particularly suitable for finishing antimicrobial of medical products, especially for finishing of the medical products already mentioned. The metal ions of the solution stabilized in this way are preferably reduced without however in the presence of a suitable reducer, in particular the Vitamin C, sodium borohydride, LiHBEt 3 or an aldehyde, with with respect to elementary metal nanoparticles. In case of use of LiHBEt 3 (Li: lithium, H: hydrogen, B: boron and Et: ethyl), as a reducer, lithium-boron species derived from that can lead to a cross link and therefore to an aggregation of the modified polyamino acids to be amphiphilic and particularly crosslinked. Consistent and particularly because of its biocompatibility, the use of Vitamin C as a reducer is especially preferred. How various organic solvents can be used, particularly isopropanol or propanol, or aromatic solvents, for example toluol or xylene, as well as mixtures thereof.

It may also be preferred to apply the material. antimicrobial complex as a solid substance, for example by spraying, or in the form of a melt or an aerosol on The product to finish.

The complex antimicrobial material preferably it is applied in an immersion procedure on the Unfinished product surface. In addition, the complex material antimicrobial can be applied by swelling in and / or on the unfinished product For the antimicrobial finish of for example Suture materials, meshes or bands may be preferred to apply the complex biocidal material with the method of passage through the tissue from the outside on the unfinished product. In addition, the material biocidal complex can be applied on the unfinished product by casting, spreading, stamping and printing techniques spraying known to the expert, particularly by compression, laminated or scratched.

According to another embodiment it is applied additionally a polymer at least partially reabsorbable, of completely reabsorbable preference, particularly in the form of a solution, on the surface of the product. So can it be preferred that the product according to the invention, after its surface coating with complex antimicrobial material, in a second coating procedure it is coated with a second layer of a resorbable polymer, particularly a polyester, a polyurethane or a silicone. As the second layer is preferably applies a resorbable copolymer and / or terpolymer, particularly based on lactide, glycolide, trimethylene carbonate, polybutyrate, para-dioxanone and / or ε-caprolactone.

As solvents can be used alcohols, aliphatic esters, ketones or aromatic solvents, ethylacetate being especially preferred. It is also possible that the resorbable polymer is applied after a treatment of surface of the medical product, particularly after a plasma activation on the product.

Alternatively to this, the polymer at least partially reabsorbable, preferably completely absorbable, and the antimicrobial complex material together can be applied in a coating process on the product Doctor to finish. This is especially advantageous, since a Unique coating process is cheaper and cheaper.

It is also possible that a ceramic and / or metal cladding, particularly according to one of the last two embodiments described, about the product a finish.

Object of the invention is also a procedure for the preparation of a medical product, in which the complex material, particularly in the form of a solution, is added additionally or alternatively to the embodiments above, in the material of the product during its manufacture or is incorporated into the latter by swelling after the product manufacturing. By adding to the product material you can be achieved a uniform distribution of complex material antimicrobial within the medical product as well as on its surface or at least in layers close to the surface of the product. Relating to other details, particularly as regards the solution as well as alternative forms of addition on the material antimicrobial complex for the medical product material, particularly as a solid substance or in the form of a melt or an aerosol, the above mentioned description is indicated.

In another advantageous embodiment, the complex antimicrobial material is mixed with the material of product and is then transformed into the desired product, being in particular extruded, spun, pressed, laminated, spilled or blown. Especially preferably, a polymer mixture and of antimicrobial complex material is converted by spinning into a thread material, which according to the type of polymer used it can be converted into a resorbable suture material or be woven or made to a knitted textile product.

The present invention further relates to a procedure for the preparation of at least one polyamino acid, especially for the manufacture of the product according to the invention, by polymerization of at least trifunctional amino acids in the phase liquid, activating the amino acids for polymerization and polymerizing them without the use of protective groups.

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In an embodiment of the procedure according to the invention organic solvents or mixtures of organic solvents for making the phase available liquid With advantage the polymerization of the amino acids is carried out in at least one solvent, selected from the group comprising dimethylsulfoxide (DMSO), dimethylformamide (DMF), dichloromethane, tetrahydrofuran (THF) and ethyl acetate.

In a preferred embodiment of the method according to the invention, the amino acids are activated by at least one substance, preferably an organic substance. How substance is used with particular advantage a nitrogen compound. The amino acids are preferably transferred into products especially reactive intermediates (intermediates), particularly in active esters, by reaction with the substance and therefore They are activated. Amino acids activated in this way can react with nucleophilic groups, particularly with amino groups, of other amino acids. Therefore, the polymerization of amino acids with respect to polyamino acid can be performed under conditions particularly mild reaction, particularly at temperature ambient.

In a special embodiment of the method according to the invention, the amino acids are activated by at least one substance of the group comprising carbodiimides, N-hydroxysuccinimide (NHS), 1-hydroxybenzotriazole (HOBT) and derivatives of same. In addition, amino acids can be activated by reaction with pentachlorophenol and / or pentafluorophenol. How carbodiimides are they can particularly use the 1-ethyl-3- (3-dimethylaminopropyl) -carbodiimide (EDC) or dicyclohexylcarbodiimide (DCC). EDC utilization It may be particularly preferred for its good water solubility. For example, the iso-urea derivative produced after a successful polymerization and derivative of EDC can be removed by simple cleaning steps, in particular by a aqueous extraction of the reaction formula. In another form of embodiment it can be significant to activate the amino acids for the DCC polymerization.

In some cases, the activation potential of carbodiimides, particularly from DCC, is not enough for a successful polymerization, since for example the products intermediates activated by carbodiimides can be deactivated particularly by sequential reactions. In these reactions unwanted sequentials can be particularly about regrouping reactions, whereby intermediate products activated, particularly active esters, can be transferred in deactivated products, particularly those amide compounds, before they can polymerize, obtaining the desired polyamino acid. In such cases it can be significant according to the invention activate amino acids by carbodiimides, in particular DCC and other substance. The other substance reacts preferably with activated intermediates formed to from carbodiimides and amino acids under the formation of new intermediate products, preferably more reactive, in Particularly under active ester formation. The products more active intermediates manufactured in this way react especially fast with amino acid groups of amino acids used for polymerization. This way it can be avoided with particular advantage a deactivation of intermediate products assets. In particular, manufacturing is therefore possible of a polyamino acid, for example a polyamino acid with a DP desired (Degree Of Polymerisation = degree of polymerization).

In an embodiment especially preferred of the process according to the invention, the amino acids are activated by dicyclohexylcarbodiimide (DCC) and N-hydroxysuccinimide (NHS).

In another preferred embodiment of the method according to the invention, the amino acids are activated by dicyclohexylcarbodiimide (DCC) and 1-hydroxybenzotriazole (HOBT).

In addition, amino acids can be activated by thionyl chloride (SOCl2) in DMF as solvent, performing activation preferably by a catalyzed transformation DMF with thionyl chloride (SOCl2).

Amino acids can also be activated by heating of the liquid phase. With particular advantage it is done by heating a condensation reaction between the groups carboxyl and amino acids under water dissociation and formation of amide bonds. Activation is done particularly at a temperature (reaction temperature) of between 100 and 150 ° C, particularly between 110 and 140 ° C. Activation and the bonding of amino acid monomers occurs particularly over a period of 8 to 96 hours, preferably for approx. 96 hours With advantage, the reaction direction can be performed at different temperatures, particularly at two temperatures different. With a particular advantage, the polymerization can take place at temperatures of approx. 140ºC and approx. 110 ° C. The reaction formula is preferably first brought to a temperature of approx. 140 ° C and maintained for approx. 48 hours a this temperature Then the reaction formula is cooled. in a preferred manner at a temperature of approx. 110 ° C and held for another approx. 48 hours at this temperature. How initial concentrations are preferably used for amino acids concentrations between 2 and 20 mol / l, in particular between 5 and 17 mol / l, preferably a concentration of approx. 15 mol / l.

It may also be preferred according to the invention. that amino acids are activated by silylated, in particular by reaction with hexamethyldisilazane (HMDS). Through the silage arise silylated amino acids, the heteroatoms of the amino acids at least partially covalently with groups of silyl, in particular with trimethylsilyl groups. Amino acids activated in this way can be polymerized by polyamino acid.

The manufactured polyamino acids can be particularly purified by filtration and / or dialysis. In case of cationic polyamino acids, in particular polycationic, the purification is performed with a particular advantage with the help of called CMC method (carboxymethyl cellulose). In the CMC method, the polyamino acids with soluble polyanionic carboxymethylcellulose in the basic aqueous environment preferably form aggregates stable insoluble. These aggregates can be separated by filtration of the aqueous environment and be washed particularly with a discretionary frequency. Therefore all dirt can be removed. The release of polyamino acids from aggregates insoluble occurs preferably by acidification in the environment aqueous, since in this way protonated carboxymethylcellulose (CMC) remains insoluble and polyamino acids enter solution. Where appropriate, using the CMC method, the phase of dialysis for cleaning polyamino acids. For a choice appropriate parameter, in particular the pH value, of the concentration, the rate of addition and the type of carboxymethyl cellulose used, it can be achieved that amino acids and individual polyamino acid oligomers do not form aggregates with CMC and with advantage can be eliminated through stages of washed.

In another preferred embodiment of the process according to the invention the liquid phase polyamino acid it is modified to be amphiphilic, particularly in the presence of bases. For the manufacture of the liquid phase they enter consideration particularly organic solvents or mixtures of organic solvents, particularly THF, as well as water. How bases are preferably used amines, particularly triethylamine According to the invention it is especially preferred that, for amphiphilic modification of polyamino acid bases are used water soluble, particularly alkaline bleach, preferably soda bleach. Preferably, the polyamino acid is dissolved in liquid phase, preferably in aqueous phase. In a form of preferred embodiment of the process according to the invention is added to this polyamino acid solution to modify a solution of the substance intended for amphiphilic modification. Preferably the substance is dissolved in at least one organic solvent, particularly THF. In addition, to this solution of polyamino acid to modify a solution is added, particularly a solution aqueous, from the base. In an embodiment especially Preferred method according to the invention, the solution of the substance intended for amphiphilic modification and the solution of the base are added in each case simultaneously to this solution of the polyamino acid. With particular advantage, the addition can occur by drip. Furthermore, according to the invention it is especially preferred that, as a substance for the amphiphilic modification of the polyamino acid, at least one fatty acid is used, preferably an acid palmitic and / or stearic acid, or a fatty acid derivative, preferably palmitic acid chloride and / or stearic acid chloride. Referring to other details refers to the description preceding.

Preferably with the aid of the procedure according to the invention described above, polyamino acids are manufactured branched, particularly hyperbranched, particularly homo-polyamino acids, preferably poly-lysine. Concerning other details refer to the preceding description.

In addition, the invention encompasses the use of a complex material of macromolecules and metal nanoparticles, the macromolecules forming at least partially of a polyamino acid and particularly surround each nanoparticle metal in the form of a wrap, such as biocide in a product doctor. Regarding other features and details, it refers to the previous description.

The product according to the invention presents biocompatible properties, particularly compatible with the tissue and simultaneously with extremely antimicrobial activity or biocides, due to the molecular structure and the structure of its finish. The composition of the complex material of own substances of the body or substances that are made up of compounds endogenous, and / or at least substances essentially compatible with the body guarantees the biocompatibility of the finished product antimicrobial

The antimicrobial properties of the finish are based both on the biocidal effect of metal nanoparticles, on particular silver nanoparticles, as well as in the effect polyamino acid biocide, particularly the poly-lysine. The reunification of these substances with antimicrobial activity in The shape of a complex material determines its high efficiency especially against harmful microorganisms or germs. With advantage particular can be achieved stabilization of nanoparticles metallic through a core-shell structure of the complex material on the one hand and therefore a uncontrollable precipitation and accumulation of metal in the body. On the other hand, the shell (Shell) hydrophobic structure core-shell confers the adhesion of the finish particularly on the surface of the product. In this way, the risk of uncontrollable or also continuous release of the metal to the environment, particularly in the surrounding tissue of the body, It can be reduced. In this respect therefore they can be diminished or essentially avoided the possible effects secondary.

Other features of the invention result of the consecutive description of preferred embodiments With the help of examples. At the same time the characteristics of the invention can be performed alone or in combination with each other. The described embodiments serve only for clarification and for the best understanding of the invention and should not be understood as restrictive at all.

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Example 1 Manufacturing of E-poly-L-lysine

To a solution of 0.200 g of hydrochloride L-lysine in 4 ml of water (dest.) Were added to ambient temperature 0.627 g of hydrochloride 1-ethyl-3- [3- (dimethylamino) propyl] carbodiimide in five portions, stirring the reaction solution between two Additions for 24 hours. At the end of the polymerization, the mixture reactive was dialyzed against water (dialysis membrane with a 2000 g / mol cut-off) and then the polypeptide. (yield: 0.016 g [9%]).

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Example 2 Polymerization of L-lysine by the addition of DCC

To a colorless stirred suspension of 200 mg of L-lysine (1.37 mmol, 1.0 equivalent) in 5 ml of Ethyl acetate 566 mmg (2.74 mmol, 2.0 equivalent) of dicyclohexylcarbodiimide. The colorless (non-dairy) suspension has been stirred for 4 days at room temperature and then reduced by solvent removal until drying. To solid substance produced 20 ml of water were added and the Colorless suspension produced was centrifuged (for 10 minutes at 4,000 revolutions per minute). The colorless solid substance Separately it was washed twice with respectively 10 ml of water. The Clear aqueous phases combined were reduced to approx. 10 ml of solution, resulting in a cloudiness. The suspension produced was filtered and the filtrate was dialyzed against water (MWCO 2000). Of the dialysis was obtained approx. 1 mg colorless polymer

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Example 3 Polymerization of L-lysine by the addition of DCC / NHS

To a colorless stirred suspension of 200 mg of L-lysine (1.37 mmol, 1.0 equivalent) in 5 ml of ethylacetate 566 mg (2.74 mmol, 2.0 equivalent) of dicyclohexylcarbodiimide and 316 mg (2.74 mmol, 2.0 equivalent) of N-hydroxysuccinimide (NHS). The milk suspension was stirred for 4 days at room temperature and then it was reduced by solvent removal until drying. To solid substance was added 20 ml of water and the colorless suspension produced was centrifuged (for 10 minutes at 4,000 revolutions per minute). The separated colorless solid substance was washed two times with respectively 10 ml of water. The clear aqueous phases gathered were reduced to approx. 10 ml, resulting in cloudiness The suspension produced was filtered and the filtrate It was dialyzed against water (MWCO 2000). From dialysis were obtained 55 mg poly-L-lysine (0.43 colorless mmol of lysine units, yield: 33%).

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Example 4 Silylated L-lysine with hexamethyldisilazane (HMDS)

9.14 g of hydrochloride were suspended from L-lysine (0.05 mol, 1.0 equivalent) in 53 ml of hexamethyldisilazane (41.02 g, 0.254 mmol, 5.1 equivalent) and the suspension was heated to 130 ° C. After 8 hours a yellow solution After 24 hours the solution showed a color dark brown. The remaining hexamethyldisilazane was removed in vacuo (63 ° C, 20 mbar) and a brown oleaginous mass was obtained Dark. By distillation (90 ° C, 0.1 mbar) 5.68 g were obtained of colorless oil of silylated L-lysine. With a Silage grade of 1.9 per lysine molecule was calculated a 40% yield with respect to L-lysine used

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Example 5 Polymerization of silylated L-lysine

2,860 mg of silylated L-lysine (a lysine ratio of approx. 0.012 mol and approx. 0.023 mol, 1.0 equivalent, trimethylsilyl ratio) were heated under reflux at 80 ° C and 1.0 ml of slowly added slowly isopropanol (0.785 g, 0.013 mol, 0.6 equivalent). Was formed slowly an orange solid substance in a yellow liquid Sure. After 8 hours it was cooled to room temperature and they added another 1.4 ml of isopropanol. After an hour it they added 2 ml of water and all the solvent as well as the Hydroxytrimethylsilane produced was removed under vacuum. The residue It was dissolved in water and dialyzed against water (MWCO 2000). Of the dialysis 60 mg of a yellowish polymer was obtained (a yield of approx. 4%).

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Example 6 Polycondensation

7.422 g of dissolved L-lysine * H2O (0.045 mol) in 5.0 ml of water in The ultrasound bath. It was then removed in the evaporator rotary so much water, until there was a cloudiness that, at Air became a clear viscous solution. By differentiation it turned out that 3.0 ml of water remained as solvent. The L-lysine aqueous solution was heated to 160 ° C (oil bath temperature) under reflux and stirred for 2 days. The temperature was then lowered to 120 ° C and stirred for another 2 days. During the reaction it was circulated regularly a slight stream of nitrogen for a few minutes in the appliance, to remove water. Once the reaction cooled to room temperature and very hard orange mass it was dissolved in water and then dialyzed against water (MWCO 2000). From the dialysis 2,278 g of polymer were obtained (yield: approx. 37%).

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Example 7 Modification of ε-poly-L-lysine

At a 12 mg suspension of ε-poly-L-lysine dried in 3 ml of i-propanol (iso-propanol) 61 µL of NEt3 was added (triethylamine) at room temperature. The formula was stirred for 30 minutes Then a solution of 142 was added µl of the mixture of palmitic acid chloride or acid stearic (mixture 40: 60,% by weight) slowly drop by drop to 1 ml of i-propanol. In this case it was applied for a few seconds a vacuum (750-800 mbar), to eliminate aerosols formed. Once the acid chloride addition is finished The reaction solution was stirred for another 24 hours at room temperature. Then 61 \ mul were added again of NEt 3 and stirred for 12 hours. Dialysis (dialysis membrane with a cut-off of 2000) mg / mol) against i-propanol was obtained ε-poly-L-lysine modified with fatty acid (degree of modification 27%, corresponds to the proportion of polylysine free amino groups that have reacted with the mixture of palmitic acid chloride and acid stearic).

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Example 8 Modification of the poly-L-lysine

0.500 g of the polylysine was dissolved synthesized (approx. 3,900 mmol, 1.0 equivalent) according to example 6 in 20 ml of water. Under stirring, a solution of 1,450 ml of acid chloride (1,313 mg, 4,500 mmol, 1.2 equivalent) was added drop by drop to 6 ml of THF at room temperature and simultaneously a solution of 0.180 g of sodium hydroxide solution (4,500 mmol, 1.2 equivalent) was added dropwise to 2 ml of water. The solution is clouded already after the addition of small amounts of solution of acid chloride Once the addition was finished, a thick milk suspension that was stirred overnight at temperature ambient. The suspension was centrifuged and then filtered and the colorless solid substance was washed twice respectively in 30 ml of water and then dried under vacuum. Then the i-propanol was added to the solid substance and the yellowish suspension was dialyzed against i-propanol (MWCO 2000). From dialysis were obtained 873 mg of polymer, that is, to the complete conversion of a yield of 60% of the poly-L-lysine used - now modified to be amphiphilic.

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Example 9 Crosslinking ε-poly-L-lysine by citric acid

First, a polymerization of 0.200 g of L-lysine hydrochloride (1.00 equivalent) according to example 1. Next and after 24 hours after the last EDC addition a fresh solution was added prepared of 0.011 g of citric acid (0.055 mmol, 0.05 equivalent) and from 0.032 g of EDC HCL (0.167 mmol, 0.15 equivalent) to 1 ml of Water. For higher crosslinking they were used therein procedure and with the same formula 0.021 g of citric acid (0.110 mmol, 0.10 equivalent) and 0.064 g of EDC HCL (0.334 mmol, 0.30 equivalent).

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Example 10 Loading of polymer articles with silver nitrate (I) and reduction

They were dissolved, under nitrogen atmosphere, 10 mg of ε-poly-L-lysine modified in 7.6 ml toluol and 5.7 mg of AgNO 3 in three servings (for 24 hours of stirring time after each addition). A clear and stable solution of silver (l) -polymer-toluol. Be diluted 0.1 ml of the solution of silver (l) -polymer-toluol (content: 0.13 mg of polymer, 0.05 mg of AgNO 3) with 2 ml of i-propanol and mixed with 0.03 ml of a solution 0.02 M L-ascorbic acid (in i-propanol). The solution colored yellow intense Alternatively, 0.1 ml of the solution can be diluted. silver (l) -polymer-toluol (content: 0.13 mg of polymer 0.05, 0.05 mg of AgNO 3) with 2 ml of i-propanol and be mixed with 0.06 ml of a 0.01 M solution (M: Molarity) Li [HBEt 3] (in THF). The solution was colored equally intense yellow.

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Example 11 Manufacture of films on glass slides

For the manufacture of a film was applied a solution of silver (0) -polymer on a marked area of approx. 1 cm2 of a glass slide with a pipette The slide was placed on a plate heating and the solvent was evaporated. At the same time, the increasingly concentrated solution is stirred with the pipette over the glass, so that a film formed in the marked area.

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Example 12 Bacterial test

Films of approx. 1 cm 2 on glass slides: 4 µg of silver in 40 µg of polymer or 10 µg of silver in 100 µg of polymer. For the preparation of the bacterial cells, 50 ml of a standard sterile culture medium from the Merck company were inoculated with 100 µl of a suspension of Staphylokokkus aureus cells (approx. 1011 cells per ml) in PBS (phosphate buffered saline, pH 7.0) and incubated for 6 hours at 37 ° C under stirring. After centrifugation of the bacteria suspension, the cells were washed twice with PBS (pH 7.0) and then resuspended with PBS and further diluted with PBS at a concentration of 5 x 10 8 cells per ml. The cell concentration was checked by absorption at 600 nm. The manufactured films were washed for 2 minutes in PBS and sprayed with the bacteria suspension. Next, the slides were placed in respectively a Petri dish and 25 ml of growth agar was added (1.5% by weight of agar in a cell growth agent was heated for 5 minutes at 100 ° C and quickly cooled to 40 ° C). Petri dishes were then incubated at 37 ° C. Films with a minimum amount of silver of 10 µg per cm 2 prevented the growth of Staphylokokkus aureus cells sprayed over to more than 99%.

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Documents cited in the description

This list of related documents by the applicant has been collected exclusively for information of the reader and is not part of the European patent document. The it has been made with the greatest diligence; the EPO without However, it assumes no responsibility for any errors or omissions

Patent documents mentioned in the description

US 2004017978 A1 [0003]

WO 2004101011 A [0006]

WO 2004056404 A [0004]

WO 2004085998 A [0007]

WO 03072143 A [0005]

DE 10323597 A1 [0019]

Claims (27)

1. Medical product provided with an antimicrobial finish of a complex material based on metal nanoparticles and macromolecules, the macromolecules being made up of at least one polyamino acid, characterized by the fact that the polyamino acid is modified to be amphiphilic by a substance and the substance is a fatty acid or a derivative of fatty acid. 2. Medical product according to claim 1, characterized in that the finish is provided at least on a part of the surface of the product, particularly in the form of a coating. 3. Medical product according to claim 1 or 2, characterized in that the finish is provided inside the product. 4. Medical product according to one of the preceding claims, characterized in that each metal nanoparticle is surrounded in the form of an envelope by at least one polyamino acid. 5. Medical product according to one of the preceding claims, characterized in that the polyamino acid is a homo- or hetero-polyamino acid, particularly a homo-polyamino acid. 6. Medical product according to one of the preceding claims, characterized in that the polyamino acid is constituted of existing and / or synthetic natural amino acids, particularly existing natural amino acids. 7. Medical product according to one of the preceding claims, characterized in that the polyamino acid contains at least one basic amino acid, acidic or sulphurous, in particular at least one amino acid of the group comprising cysteine, methionine, tryptophan, histidine, arginine , lysine, ornithine, aspartic acid, glutamic acid and its derivatives. 8. Medical product according to one of the preceding claims, characterized in that the polyamino acid has a linear structure. 9. Medical product according to one of claims 1 to 7, characterized in that the polyamino acid has a branched structure, preferably hyperbranched. 10. Medical product according to one of the preceding claims, characterized in that the polyamino acid is polylysine, particularly poly-α-lysine and / or poly-lysine, preferably poly-lysine. 11. Medical product according to claim 10, characterized in that the polylysine has a degree of polymerization (DP, Degree Of Polimerisation) 10 to 15, in particular 12 to 14, preferably approx. 13. 12. Medical product according to claim 10 or 11, characterized in that the polylysine has a molecular weight of between 3,000 and 6,000 g / mol, particularly between 4,000 and 5,000 g / mol. 13. Medical product according to one of the preceding claims, characterized in that the substance is a palmitic and / or stearic acid. 14. Medical product according to one of the preceding claims, characterized in that the amphiphilic modification of the polyamino acid is based on covalent bonds, particularly amide bonds. 15. Medical product according to one of the preceding claims, characterized in that the proportion in free amino groups after amphiphilic modification is between 0.5 and less than 50%, in particular between 10 and 40%, particularly between 20 and 40%, preferably it is approx. 37% with respect to the total amount of amino groups originating from the amino acid monomers used for the preparation of the polyamino acid, preferably lysine monomers. 16. Medical product according to one of the preceding claims, characterized in that the substance is linked, in particular by covalent bond, with the polyamino acid by means of a crosslinking component, in particular a polyfunctional carboxylic acid, preferably citric acid. 17. Medical product according to one of the preceding claims, characterized in that the proportion in free amino groups after the amphiphilic modification of the crosslinked polyamino acid is between 15 and 45%, particularly between 25 and 35%, preferably it is approx. . 30%, with respect to the total amount of amino groups originating from the amino acid monomers used for the preparation of the polyamino acid, preferably lysine monomers.

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18. Medical product according to one of the preceding claims, characterized in that the metal nanoparticles are gold, silver, copper or zinc nanoparticles, silver nanoparticles being preferred. 19. Medical product according to one of the preceding claims, characterized in that the metal nanoparticles have a diameter of 0.5 to 20 nm, particularly 1 to 20 nm, preferably 1 to
14 nm 20. Method of manufacturing a medical product according to one of claims 1 to 19, characterized in that the complex material is applied, particularly in the form of a solution, from the outside, on the unfinished product or is added to the material of the product during its manufacture. 21. Method of manufacturing at least one polyamino acid, especially for the preparation of a medical product according to one of claims 1 to 19, by polymerization of at least trifunctional amino acids in the liquid phase, characterized in that the amino acids are activated for polymerization and are polymerized without application of protecting groups. 22. Method according to claim 21, characterized in that the amino acids are activated by at least one substance, preferably an organic substance. 23. Method according to claim 21 or 22, characterized in that the amino acids are activated by at least one substance of the group comprising carbodiimides, N-hydroxysuccinimide (NHS), 1-hydroxybenzotriazole (HOBT), pentafluorophenol, pentachlorophenol and derivatives of the same. 24. Method according to one of claims 21 to 23, characterized in that the amino acids are activated by dicyclohexylcarbodiimide (DCC) and N-hydroxysuccinimide (NHS). 25. Method according to one of claims 21 to 24, characterized in that the amino acids are activated by dicyclohexylcarbodiimide (DCC) and 1-hydroxybenzotriazole (HOBT). 26. Method according to one of claims 21 to 25, characterized in that the polyamino acid is modified to be amphiphilic, particularly in the presence of bases. 27. Use of a complex material consisting of metal nanoparticles and macromolecules as a biocide in a medical product, particularly in a product of this class according to one of claims 1 to 19, in which the macromolecules are at least partially constituted of a polyamino acid, characterized in that the polyamino acid is modified by a substance to be amphiphilic and the substance is a fatty acid or a derivative of the fatty acid.