Multi-drug antibacterial coating

Abstract

The present invention relates to a polymer-based antimicrobial coating, preferably for the prevention and / or treatment of infections associated with medical devices. The present invention also relates to a coating and a method for producing an intermediate antibiotic preparation that can be applied as a coating to a surface of a medical device. The coating as part of the present invention is compatible with multiple antibiotics, preferably two or more antibiotics with different hydrophilicity and / or polarity. The coating as part of the present invention preferably releases effective amounts of multiple antibiotics over a period of six weeks or more.

Description

[Technical field]

[0001] The present invention relates to polymer-based antimicrobial coatings, preferably for the prevention and / or treatment of infections associated with medical devices. Additionally, the present invention relates to methods of producing the coatings and intermediate antibiotic preparations thereof, which can be applied as coatings to surfaces of medical devices. [Background technology]

[0002] Bacterial infection is a major risk when implanting medical devices. Staphylococcus spp. in particular can form biofilms on the devices that are resistant to treatment. Persistent infection may eventually necessitate removal of the device. For this reason, patients undergoing surgery are often treated with antibiotics or other antimicrobial substances (antimicrobial agents) to minimize the possibility of biofilm formation.

[0003] Preferably, the prophylactic measures provide sustained release of multiple antibiotics. First, it has been clinically proven that the delivery of multiple antibiotics is more effective at preventing bacterial (instrument-associated) infections compared to the use of a single antibiotic. For example, a combination of antibiotics with different mechanisms of action can more effectively eradicate both free-floating and biofilm-forming bacteria. Second, medical device infections can occur directly (i.e., immediate infection, via contamination of the wound) or weeks to months after surgery (i.e., delayed infection, via bacterial spread from more distant sites of infection). Therefore, the release of suitable agents to prevent immediate and delayed infections can range from hours to weeks, depending on the composition.

[0004] Although prophylactic antibiotics are generally delivered systematically, local delivery systems for antibiotics can provide higher local drug concentrations while minimizing systemic drug toxicity. For example, in the field of orthopedics, vancomycin and gentamicin are commonly delivered to the surgical site using polymethylmethacrylate (PMMA) beads as a carrier material. However, resorbable polymers have several advantages over PMMA beads because they eliminate the need for a second surgery to remove the beads. Furthermore, the release kinetics of the drug can be tailored to achieve timely drug release, whereby drug release is due to the diffusion and degradation rate of the drug and the chemical structure of the selected polymer.

[0005] The antimicrobial polymer composition can be applied as a thin film (also referred to as an "antimicrobial coating") to the surface of the device by a variety of techniques to optimally protect the implant surface from bacterial colonization. The preparation of the antimicrobial polymer coating generally involves the following steps: 1. Dissolving a polymer in a solvent to obtain a polymer preparation; 2. Dissolving an antibiotic in a solvent to obtain an antibiotic preparation; 3. Mixing the polymer preparation with the antibiotic preparation to obtain a polymer antibiotic preparation; 3. Applying the polymeric antibiotic preparation as a coating on the medical device; 4. (Optional) Evaporating the Solvent Includes.

[0006] Despite the great clinical demand, the incorporation of multiple antibiotics into the same polymer coating by the above-mentioned methods is not easy. The preparation of multi-drug polymer coatings is particularly difficult when two or more antibiotics (and the necessary solvents) have different physicochemical properties (hydrophilicity, polarity, and / or miscibility in water). The reasons for this include, for example:

[0007] - First, antibiotics with different hydrophilicity / polarity are believed to require different organic solvents. In hydrophobic polymer compositions, hydrophilic drugs have the problem of low loading efficiency. Therefore, lipophilic drugs are often preferred in hydrophobic polymer compositions, and hydrophilic drugs are often preferred in hydrophilic polymer compositions. In addition, lipophilic drugs are widely soluble in organic solvents, while hydrophilic drugs are only compatible with limited organic solvents (US Patent No. 2010215716). Simply mixing multiple antibiotics in their respective organic solvents typically leads to low drug solubility, poor miscibility, and / or drug precipitation. Ultimately, this leads to low drug loading efficiency and undesirable drug release characteristics (i.e., drug shortage or non-sustained release).

[0008] - Secondly, a high content of high molecular weight polymer in the polymer preparation typically results in a high viscosity of the polymer antibiotic preparation. This prevents the formation of a homogeneous, thin coating by one of the various coating methods. For example, electrospraying is the preferred coating method, but requires the preparation to have a relatively low viscosity. High viscosity polymer antibiotic coatings result in inhomogeneous or non-uniform coatings that exhibit poor drug release characteristics. A higher polymer content in the polymer preparation ensures a high polymer-drug ratio, allowing for the incorporation of a higher amount of antibiotic (or antibiotics). The inclusion of a higher amount of antibiotic (or antibiotics) allows for better encapsulation, improved coating, and extended drug release period.

[0009] - Third, the release rate of a drug from a polymer composition is affected by the diffusion rate of the drug. It is generally believed that the incorporation of hydrophilic (polar) and hydrophobic (non-polar) antibiotics into a polymer coating leads to unpredictable diffusion rates of the antibiotics. Moreover, it has been observed in the prior art that a mismatch in the diffusion rates of hydrophilic (polar) and hydrophobic (non-polar) antibiotics occurs when they are not properly loaded in the same polymer.

[0010] Various approaches have been investigated to simultaneously deliver (co-transport) antibiotics with different physicochemical properties. Examples include the use of lipid nanoparticles, e.g., liposomes, which encapsulate hydrophilic drugs in a water-soluble core and transport lipid-soluble antibiotics within the phospholipid bilayer (Forier et al. J Control Release. 2014 Sep 28;190:607-23). ​​However, this methodology does not provide sufficient sustained drug release characteristics to protect against both immediate (hours) and delayed (weeks) infections. Instead, co-delivery (co-transport) of multiple drugs with different physicochemical properties (e.g., hydrophilicity, polarity, and / or water miscibility) has opted for the use of different polymer compositions to modulate the release profile of each drug over a wide time range (Ritsema. Int J Pharm 2018 Sep 11;548(2):730-739, Jahanmard et al. J Control Release. 2020 Oct 10;326:38-52). For example, hydrophilic and hydrophobic antibiotics were each encapsulated in different polymers that were then combined into specific structures. Using this method, hydrophilic vancomycin was encapsulated in hydrophobic polycaprolactone (PCL) polymer fibers and hydrophobic rifampin was encapsulated in hydrophobic polylactic glycolic acid (PLGA) fibers, which were then coated in layers (Jahanmard et al. J Control Release. 2020 Oct 10;326:38-52.).

[0011] There is a need for multi-drug antimicrobial polymer coatings, particularly coating formulations that are easily adaptable to incorporate different antibiotics of choice (i.e., tailored to the clinical scenario) within a single thin film and / or a single polymer matrix.

[0012] More specifically, there is demand for: - Antibacterial coatings, especially coating preparations in which two or more antibiotics with different physicochemical properties, e.g. different hydrophilicity (polarity), are incorporated into a single polymer matrix, preferably in a single layered coating within the same polymer matrix.

[0013] - Antibacterial preparations incorporating two or more antibiotics with different physicochemical properties, e.g. different hydrophilicity (polarity), and suitable formulation characteristics (low viscosity, high drug loading, high drug solubility) for application by coating means (preferably spraying, such as electrospray).

[0014] -An antimicrobial coating comprising two or more antibiotics (e.g., with different physicochemical characteristics) encapsulated in a single polymer matrix in sufficient amounts to extend the release profile of the drug, e.g., in amounts effective to inhibit the growth of and / or kill microorganisms, for at least several weeks (preferably 6 weeks or more) after implantation of the implant. [Prior art documents] [Patent documents]

[0015] [Patent Document 1] U.S. Patent No. 2010215716 [Non-patent literature]

[0016] [Non-Patent Document 1] Forier et al. J Control Release. 2014 Sep 28;190:607-23 [Non-Patent Document 2] Ritsema. Int J Pharm 2018 Sep 11;548(2):730-739 [Non-Patent Document 3] Jahanmard et al. J Control Release. 2020 Oct 10;326:38-52 [Non-Patent Document 4] Wang et al. Electrospraying: Possibilities and Challenges of Engineering Carriers for Medical Applications- A Mini Review. Front. Chem., 25 April 2019 [Non-Patent Document 5] Soliman et al. (Acta Biomaterialia 6 (2010) 1227-1237) [Non-Patent Document 6] Bartos et al. Biomed Eng Online. 2018 Aug 17;17(1):110 [Non-Patent Document 7] Biomaterials. 2008 May;29(13):1989- 2006 [Non-Patent Document 8] Adv Drug Deliv Rev. 2011 Apr 30;63(4-5):209-20 Summary of the Invention

[0017] The present disclosure relates to antimicrobial preparations (coating solutions), preferably multi-drug antimicrobial preparations, and methods for their manufacture. The present disclosure further relates to antimicrobial coatings obtained when the antimicrobial preparations are applied as thin films onto medical devices, for example by spraying (e.g. electrospraying), spin-coating or electrospinning. The present disclosure further relates to the use of the antimicrobial preparations and antimicrobial coatings in the prevention and / or treatment of infections associated with medical devices, in particular infections associated with implants in orthopedic surgery.

[0018] The present inventors have discovered that in a method for producing a polymeric antibiotic preparation for subsequent application of an antimicrobial coating, the use of a hydrophobic (non-polar) antibiotic, such as a rifamycin, a macrolide, or a tetracyline, significantly reduces the viscosity of the preparation. The hydrophobic (non-polar) antibiotic is preferably prepared by the following method; a) providing a first solvent containing a polymer, said first solvent being a fluorinated solvent and said polymer being an aliphatic polyester; b) providing a second solvent comprising a first antibiotic, said first antibiotic being soluble in a hydrophobic (non-polar) and / or non-polar organic solvent; c) mixing the first solvent containing the polymer of step a) with the second solvent containing the first antibiotic of step b) to obtain a mixture having a lower dynamic viscosity than the first solvent containing the polymer of step a); d) providing a third solvent comprising a second antibiotic, said second antibiotic preferably being a hydrophilic (polar) and / or polar aprotic organic solvent; e) mixing the mixture solution obtained in step c) with a third solvent containing a second antibiotic of step d) to obtain an antibacterial preparation. It has been found that application of the above at 1000 .mu.m results in a low viscosity formulation.

[0019] The first antibiotic and the second antibiotic may be selected based on the particular clinical need (eg, type of infection, type of surgery, type of medical device, etc.).

[0020] Antimicrobial preparations according to the present disclosure preferably have a dynamic viscosity of 1 mPa·s to 20 Pa·s (Pascal-seconds), preferably 1 mPa·s to 2 Pa·s, more preferably 1 mPa·s to 200 mPa·s. Antimicrobial preparations with low viscosity allow in particular coating by spraying, including electrospraying (e.g. when the dynamic viscosity is between 200 mPa·s and 20 Pa·s) or by spinning, including spin-coating and electrospinning (e.g. when the dynamic viscosity is between 200 mPa·s and 20 Pa·s).

[0021] In one preferred embodiment, the antimicrobial preparation according to the present disclosure has a dynamic viscosity of 0.1-500 mPa·s, preferably 1-250 mPa·s, more preferably 10-200 mPa·s, even more preferably 20-100 mPa·s.

[0022] Preferably, the antibacterial preparation according to the present disclosure has a high polymer and drug content. For example, the polymer content may be 40-90% by weight, preferably 50-80% by weight, of the antibacterial preparation. For example, the first antibiotic (preferably a hydrophobic antibiotic, e.g., rifamycin) and the second antibiotic (preferably a hydrophilic antibiotic, e.g., vancomycin) may each be present at 5-40% by weight, preferably 10-30% by weight, of the antibacterial preparation. Additionally or alternatively, the polymer may be present at 10-300 mg / ml (w / v), preferably 50-150 mg / ml, of the antibacterial preparation. The first antibiotic (preferably a hydrophobic antibiotic, e.g., rifamycin) and the second antibiotic (preferably a hydrophilic antibiotic, e.g., vancomycin) may each be present at 10-200 mg / ml, preferably 20-100 mg / ml, of the antibacterial preparation.

[0023] In one embodiment, the antibacterial preparation is prepared by dissolving a hydrophobic (non-polar) antibiotic in a non-polar or polar aprotic solvent. To reduce the viscosity of the polymer-antibiotic composition, the antibiotic solution is mixed with a polymer (preferably an aliphatic polyester, more preferably a hydrophobic aliphatic polyester) dissolved in a fluoro-based solvent (preferably a fluorocarbon or a fluoroalcohol). This polymer-antibiotic preparation may be effectively combined with a solution containing a second antibiotic to provide a multi-drug antibacterial preparation. For example: PDLG (DL-lactide / glycolide copolymer) may be provided in tetrafluoroethylene as the polymer solution, rifampicin may be provided in a non-polar organic solvent (preferably chloroform) as the first antibiotic solution, and vancomycin may be provided in a polar aprotic solvent (preferably dimethylsulfoxide) as the second antibiotic solution. Following the coating process, an antibacterial coating may be obtained that contains a high content of hydrophobic (non-polar) and hydrophilic (polar) antibiotics, both dispersed in a single polymer matrix.

[0024] The inventors have further discovered that the antimicrobial preparations of the present disclosure provide several advantages with respect to coating manufacture, among other possible advantages. The antimicrobial preparations allow for coating by techniques such as spraying and spinning. The antimicrobial preparations of the present disclosure allow for the incorporation of higher amounts of agent. Additionally, the reduced viscosity of the antimicrobial preparations of the present invention can lead to more uniform coatings, faster drying times, less shrinkage, more complete filling, and fewer air pockets, among other possible advantages.

[0025] The inventors have further discovered that the antimicrobial preparation according to the present disclosure and its subsequent application as a coating can easily accommodate the selection of antibiotic(s) even if the antibiotics to be used have different physicochemical properties (e.g., hydrophilicity, polarity). For example, it has been shown that a hydrophilic aminoglycoside (preferably tobramycin, gentamicin, streptomycin, or neomycin) or a hydrophilic glycopeptide (preferably vancomycin) can be combined with a hydrophobic rifamycin (preferably rifampin), a hydrophobic macrolide (preferably erythromycin), or a hydrophobic tetracycline (preferably minocycline) while maintaining high solubility of the drug and low viscosity of the antimicrobial preparation.

[0026] By virtue of the provision of the antimicrobial preparations of the present disclosure, multi-drug antimicrobial coatings having high polymer and / or high drug loadings are now feasible, for example, where the polymer is present at 40-90% by weight of the antimicrobial coating, preferably 50-80% by weight, and the first and second antibiotics are each present at 5-40% by weight of the antimicrobial coating, preferably 10-30% by weight.

[0027] The inventors have discovered that high drug loading (and antibiotic co-administration) in the antimicrobial coating results in long-term drug delivery, e.g., at least 6 weeks or more. Furthermore, the inventors have demonstrated sustained antimicrobial efficacy against Staphylococci spp. (i.e., the most common causative agents of metal implant infections), e.g., bactericidal efficacy against Staphylococci spp. for up to 6 weeks.

[0028] In a preferred embodiment of the present disclosure, it has been shown that the coating is suitable for long-term delivery of rifampin when used together with a second (hydrophilic or hydrophobic) antibiotic. Rifampin is unique in that it can kill Staphylococci spp. in both planktonic and biofilm states, however, it must be co-delivered with a second antibiotic to prevent resistance to rifampin. Rifampin is a large hydrophobic molecule. The second antibiotic may be a commonly used broad-spectrum antibiotic, such as gentamicin, vancomycin, or tobramycin, but typically these are large hydrophilic / polar molecules. The inventors have discovered that such combinations of preferred drugs may be incorporated by the antimicrobial preparations of the present disclosure as a single polymer and a single thin film coating.

[0029] In a more preferred embodiment, the antimicrobial coating as part of the present disclosure is suitable for long-term rifampin delivery used together with vancomycin. Unexpectedly, the inventors have discovered the fact that the presence of a hydrophilic antibiotic (e.g., vancomycin) can slow the diffusion of a hydrophobic antibiotic (e.g., rifampin) from the polymer matrix. Conversely, the presence of rifampin can slow the diffusion of vancomycin. Since both antibiotics are released more simultaneously rather than more at the same time, the antimicrobial effect is enhanced and the risk of bacterial resistance development is reduced. The inventors believe that the hydrophobic antibiotic does not easily diffuse out of the hydrophobic polymer matrix, and that incorporating a hydrophilic antibiotic can aid in better release and better diffusion of the hydrophobic antibiotic. [Brief description of the drawings]

[0030] [Figure 1]Rifampicin release profile from coated titanium discs. The role of hydrophobic drugs and / or non-polar organic solvents was examined. PDLG (DL-lactide / glycolide copolymer) was used as the polymer in the coating solution (dissolved in tetrafluoroethylene). Values ​​represent the mean + / - standard deviation (n=3). Rif: rifampicin, Van: vancomycin, DMSO: dimethylsulfoxide. [Diagram 2] Vancomycin release profile from coated titanium discs. The role of hydrophobic drugs and / or non-polar organic solvents was examined. PDLG (DL-lactide / glycolide copolymer) was used as the polymer in the coating solution (dissolved in tetrafluoroethylene). Values ​​represent the mean + / - standard deviation (n=3). Rif: rifampicin, Van: vancomycin, DMSO: dimethylsulfoxide. [Diagram 3] Rifampicin release profile from coated titanium discs. Different hydrophobic / hydrophilic drug combinations were tested. PDLG (DL-lactide / glycolide copolymer) (dissolved in tetrafluoroethylene) was used as the polymer in the coating solution. Values ​​represent the mean + / - standard deviation (n=3). Rif: rifampicin, DMSO: dimethylsulfoxide. [Figure 4] Vancomycin release profile from coated titanium discs. Different hydrophobic / hydrophilic drug combinations were tested. PDLG (DL-lactide / glycolide copolymer) (dissolved in tetrafluoroethylene) was used as the polymer in the coating solution. Values ​​represent the mean + / - standard deviation (n=3). Rif: rifampicin, Van: vancomycin, DMSO: dimethylsulfoxide. [Diagram 5]Rifampicin release profile from coated titanium discs. Different polymers (solution A) were compared (dissolved in tetrafluoroethylene). Coating solutions further contained rifampicin / chloroform (solution A) and vancomycin / dimethylsulfoxide (solution D). In addition, different coating methods were also tested. Values ​​represent the mean + / - standard deviation (n=3). PDLG: DL-lactide / glycolide copolymer, PLDL: L-lactide / DL-lactide copolymer, PLC: L-lactide / caprolactone copolymer, PL: poly(L-lactide), PCL: polycaprolactone. [Figure 6] Vancomycin release profile from coated titanium disks. Different polymers (solution A) were compared (dissolved in tetrafluoroethylene). Coating solutions further included rifampicin / chloroform (solution A) and vancomycin / dimethylsulfoxide (solution D). In addition, different coating methods were also tested. Values ​​represent the mean + / - standard deviation (n=3). PDLG: DL-lactide / glycolide copolymer, PLDL: L-lactide / DL-lactide copolymer, PLC: L-lactide / caprolactone copolymer, PL: poly(L-lactide), PCL: polycaprolactone. [Figure 7] Rifampicin release profile from coated titanium discs. PDLG (DL-lactide / glycolide copolymer) was used as the polymer in the coating solutions (dissolved in tetrafluoroethylene at 200 mg / ml). The coating solutions further contained rifampicin / chloroform (solution A, 70 mg / ml or 50 mg / ml) and vancomycin / dimethylsulfoxide (solution D, 70 mg / ml or 50 mg / ml). Values ​​represent the mean + / - standard deviation (n=3). PDLG: DL-lactide / glycolide copolymer, Rif: rifampicin, Van: vancomycin. [Figure 8]Vancomycin release profile from coated titanium disks. PDLG (DL-lactide / glycolide copolymer) was used as the polymer in the coating solutions (dissolved in tetrafluoroethylene at 200 mg / ml). The coating solutions further contained rifampicin / chloroform (solution A, 70 mg / ml or 50 mg / ml) and vancomycin / dimethylsulfoxide (solution D, 70 mg / ml or 50 mg / ml). Values ​​represent the mean + / - standard deviation (n=3). PDLG: DL-lactide / glycolide copolymer, Rif: rifampicin, Van: vancomycin. [Figure 9] Differences in viscosity of coating solutions obtained by the two methods. In method A, rifampicin was first dissolved in chloroform and then mixed with the polymer (PLGA) solution. In method B, rifampicin was added directly to the polymer (PCL) solution. The rifampicin / polymer solution was mixed with the vancomycin solution to obtain the coating solution. The solutions obtained by method A and method B were placed on a shaker, respectively, and the shaker speed was accelerated from 0 to 500 rpm and then decelerated to a complete stop. Images were taken every second for 45 seconds. The horizontal line indicates the flow of the solution during the shaking process. [Figure 10] AFM images at different magnifications of the coating obtained by electrospraying the coating solution obtained by method A. [Figure 11] AFM images at different magnifications of the coating obtained by electrospraying the coating solution obtained by method B. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Detailed Description of the Disclosure The present disclosure provides a method for producing an antimicrobial preparation comprising: a) providing a first solvent containing a polymer, said first solvent being preferably a fluorinated solvent and said polymer being preferably an aliphatic polyester; b) providing a second solvent comprising a first antibiotic, said first antibiotic being preferably soluble in a hydrophobic (non-polar) and / or non-polar organic solvent; c) mixing the first solvent containing the polymer of step a) with the second solvent containing the first antibiotic of step b), preferably obtaining a mixture having a lower dynamic viscosity than the first solvent containing the polymer of step a); d) providing a third solvent comprising a second antibiotic, said second antibiotic preferably being soluble in a hydrophilic (polar) and / or polar aprotic organic solvent; e) mixing the mixture obtained in step c) with a third solvent containing the second antibiotic of step d) to obtain an antibacterial preparation; The present invention relates to a manufacturing method comprising the steps of:

[0032] As stated above, the present disclosure provides an antimicrobial preparation obtainable by the method for preparing an antimicrobial preparation disclosed herein, comprising: a polymer, preferably in a concentration of 10-300 mg / ml of the antimicrobial preparation, more preferably 50-150 mg / ml, which is preferably an aliphatic polymer, for example a hydrophobic aliphatic polyester, more preferably one or more of PDLG (DL-lactide / glycolide copolymer), PLGA (L-lactide / glycolide copolymer), PLC (L-lactide / caprolactone copolymer), PCL (polycaprolactone), PD [poly(D-lactide)], PL [poly(L-lactide)] or PDL [poly(DL-lactide)], most preferably PDLG; a first antibiotic, preferably in a concentration of 10-200 mg / ml of antibacterial preparation, more preferably 20-100 mg / ml, which is preferably soluble in a hydrophobic and / or non-polar organic solvent, preferably one or more of rifampicin, a hydrophobic hydroquinolone, a macrolide, a tetracycline or a lincosamide, more preferably rifampin; a second antibiotic, preferably in a concentration of 10-200 mg / ml of the antibacterial preparation, more preferably 20-100 mg / ml, which is preferably soluble in a hydrophilic and / or polar aprotic organic solvent and is preferably one or more of a glycopeptide, an aminoglycoside, a β-lactam, a carbapenem, a hydrophilic fluoroquinolone or a streptogramin, more preferably vancomycin; a non-polar organic solvent, preferably at a concentration of 10-50% (v / v), more preferably 20-40% (v / v), relative to the antimicrobial preparation, preferably one or more of chloroform, pentane, hexane, benzene, diethyl ether and 1,40-dioxane, more preferably chloroform; and / or a polar aprotic organic solvent, preferably at a concentration of 1 to 40% (v / v) relative to the antimicrobial preparation, more preferably 10 to 30% (v / v), preferably one or more of dimethyl sulfoxide, dichloromethane, tetrahydrofuran, ethyl acetate, acetonitrile, dimethylformamide, dimethyl sulfoxide, acetone and hexamethylphosphoric triamide, more preferably dimethyl sulfoxide, The present invention relates to an antibacterial preparation comprising:

[0033] The present disclosure also relates to a method for preparing an antimicrobial coating, comprising the steps of applying an antimicrobial preparation as disclosed herein to a substrate (preferably a medical device, more preferably an orthopedic implant) and removing one or more solvents in the antimicrobial preparation, wherein application to the substrate is preferably carried out using dip coating, spin coating, spraying, electrospinning, electrophoretic deposition, sputter coating, thermal spraying, plasma spraying, sol-gel, layer-by-layer coating, more preferably electrospraying.

[0034] The present disclosure further provides an antimicrobial coating obtainable by the method for preparing the antimicrobial coating disclosed herein, comprising: - a polymer, preferably in an amount of 40-90% by weight, more preferably 50-80% by weight of the antimicrobial coating, which is an aliphatic polyester, preferably a hydrophobic aliphatic polyester; - a first antibiotic, preferably in an amount of 5-40% by weight of the antimicrobial coating, more preferably 10-30% by weight, the first antibiotic being soluble in a hydrophobic and / or non-polar organic solvent; and a second antibiotic, preferably at a concentration of 5-40% by weight of the antimicrobial coating, more preferably 10-30% by weight, said second antibiotic being soluble in hydrophilic and / or polar aprotic organic solvents, Including, The first antibiotic and the second antibiotic are included in an antimicrobial coating that is contained within a matrix provided by the polymer.

[0035] In one embodiment, the method for preparing the antimicrobial preparation disclosed herein comprises the steps of: The process is as follows: a) providing a first solvent containing a polymer, said first solvent being a fluorinated solvent and said polymer being an aliphatic polyester; b) providing a second solvent comprising a first antibiotic, said first antibiotic being soluble in a hydrophobic (non-polar) and / or non-polar organic solvent; c) mixing a first solvent containing the polymer of step a) with a second solvent containing the first antibiotic of step b) to obtain a mixture having a lower dynamic viscosity than the first solvent containing the polymer of step a); d) providing a third solvent comprising a second antibiotic, said second antibiotic being soluble in a hydrophilic and / or polar aprotic organic solvent; e) mixing the mixture obtained in step c) with a third solvent containing the second antibiotic of step d) to obtain an antibacterial preparation; Includes.

[0036] The term "antimicrobial material" as used in this disclosure relates to a material that inhibits the growth of and / or kills microorganisms (e.g., bacteria, fungi, viruses, preferably bacteria). The term "antimicrobial" as used in this disclosure may further refer to the growth-inhibiting and / or killing effect of the antimicrobial material on microorganisms. Antimicrobial agents disclosed herein preferably include one or more of antibiotics, antivirals, antifungals, and antiparasitics. Preferably, antimicrobial agents disclosed herein are not antiseptics.

[0037] The term "antibiotic" as used in this disclosure refers to antimicrobial compounds or agents that target bacteria and / or fungi; and / or inhibit the function of bacteria and / or fungi. Antibiotics are organic substances, typically derived from microorganisms, that generally bind to specific target molecules in bacteria and fungi. Their mechanism of action may be one or more of: inhibition of nucleic acid synthesis, inhibition of protein biosynthesis, disruption of membranes, functioning as antimetabolites, inhibition of cell wall biosynthesis. In a preferred embodiment, the coating and / or coating solution does not include antiseptics as part of this disclosure. Antiseptics refer to chemicals, typically chemicals that reduce bacterial growth or kill bacteria by a non-specific mechanism. Antiseptics are typically classified according to their mechanism of action as either small molecules (peroxides, iodine, phenols) that react indiscriminately with organic compounds and kill microorganisms, or more complex molecules that disrupt bacterial cell walls. Examples of common antiseptics include phenols, alcohols, quinolines, diguanides (e.g., chlorhexidine), alcohols, peroxides, and iodine. Antiseptics are generally applied topically and cannot usually be taken orally or ingested due to their toxicity. Thus, antiseptics are generally not suitable for use as antimicrobials or antibiotics as referred to in this disclosure.

[0038] In one embodiment, the present disclosure does not use disinfectants, such as those mentioned above.

[0039] The term "polymer" as used herein may refer to either / both homopolymers and copolymers. A homopolymer is a polymer that contains only one type of monomer. A copolymer is a polymer formed by connecting two (or more) different types of monomers in the same polymer chain. The copolymers in the present disclosure may be alternating copolymers (typically containing only two types of repeat units, which are arranged in alternating fashion along the polymer chain), block copolymers (typically containing repeat units, which are in the same block), or graft copolymers (typically containing branches of different chemical structures, which are attached to the main chain). The polymers disclosed in the present disclosure may be natural polymers or / and synthetic polymers.

[0040] The polymers disclosed in the present disclosure include: The polymer may be one or more of poly(α-ester), polyglycolide, polylactide (e.g., poly(L-lactic acid) (PLLA), poly(D-lactic acid) (PDLA), poly(D,L-lactic acid) (PDLLA), meso-poly(lactic acid)), polycaprolactone, poly(propylene fumarate), polyanhydride, polyacetal, poly(orthoester), polycarbonate, polyurethane, polyphosphazene, polyphosphoester, or a copolymer comprising one or more of these. The polymer disclosed in the present disclosure may be a combination polymer, i.e., a polymer in which the monomer contains multiple degradable groups (e.g., poly(ester ether), poly(amide ester)). The polymer disclosed in the present disclosure may be one or more proteins, e.g., collagen, elastin, albumin, fibrin. The polymers disclosed in this disclosure may be polysaccharides (e.g., hyaluronic acid, chondroitin sulfate, chitin, chitosan, alginate, dextran, agarose, mannan, inulin). The polymers disclosed in this disclosure may be natural poly(amino acids) [e.g., poly(γ-glutamic acid), poly(L-lysine)]. The polymers disclosed in this disclosure may be synthetic poly(amino acids) [e.g., poly(L-glutamic acid), poly(aspartic acid)].

[0041] Preferably, the polymers referred to in this disclosure are resorbable. The term "resorbable" as used in this disclosure is used to describe a material that is degraded in aqueous medium and / or after implantation in the body over time. The resorbability of a material (such as a coating) is generally determined by a combination of physicochemical degradation, enzymatic activity, and cellular degradation (immune response, foreign body response). Preferably, the degradation rate of a material is established in a controlled in vitro environment, although the degradation rate may vary in the body. The controlled in vitro environment may include incubating the material in excess PBS (pH 7.4) at 37°C, and the polymer is "resorbable" if at least 50% by mass is degraded after 8 weeks, preferably after 6 weeks, and more preferably after 4 weeks.

[0042] As used throughout this disclosure, the term "resorbable" may be used interchangeably with "bioresorbable," "(bio)degradable," and "(bio)erodible."

[0043] The term "solvent" as used in the present disclosure relates to a liquid in which a material / substance can dissolve to form a solution. Preferably, a liquid acts as a solvent for a particular material / substance if said material / substance has a solubility in said liquid of at least 0.1 in 100 (0.1 mg / ml), preferably 1 in 100 (1 mg / ml).

[0044] The term "soluble" as used in this disclosure means that the substance of interest (e.g., a polymer or an antibiotic) has a solubility in a liquid (preferably a solvent) of at least 0.1 in 100 (0.1 mg / ml), preferably 1 in 100 (1 mg / ml). Solubility is typically measured according to a technique in which an excess of the substance is suspended in the liquid (solvent) and shaken for 24 hours at 25°C. After filtering the solution, the substance concentration in the solution is measured, for example, using UV (ultraviolet light) or HPLC (high performance liquid chromatography).

[0045] The term "fluorine-based solvent" used in this disclosure relates to a solvent containing fluorine. The term "fluorine-based solvent" used in this disclosure can be used interchangeably with "fluorous solvent" and "fluorosolvent" in this disclosure. The term "fluorine-based solvent" disclosed in this disclosure is preferably one or more of fluoroalcohols or fluorocarbons. The fluoroalcohols disclosed in this disclosure may be one or more of (2,2,2,-trifluoroethanol), trifluoroethyl alcohol, hexafluoro-2-propanol, and trifluoropropanol. The fluorocarbons disclosed in this disclosure may be one or more of dichlorofluoromethane (CHCl2F), trichlorofluoromethane (CCl3F), tetrafluoromethane (CF4), difluorodichloromethane (CHCl2F2), chlorodifluoromethane (CHClF2), and tetrafluoroethylene (TFE, C2F4).

[0046] In various embodiments, the solvent for the polymer disclosed in the present disclosure is not a fluorinated solvent disclosed in the present disclosure. In one embodiment, the solvent for the polymer disclosed in the present disclosure is a non-polar solvent. In one embodiment, the solvent for the polymer disclosed herein is a polar aprotic solvent. In an embodiment, the solvent for the polymer disclosed herein is a polar protic solvent.

[0047] In the present disclosure, the term "hydrophobic" may be used interchangeably with the terms "non-polar" or "lipophilic" when describing preferably antibiotics and polymers. In the present disclosure, the term "hydrophilic" may be used interchangeably with the term "polar" when describing preferably antibiotics and polymers. Hydrophobic and / or non-polar compounds (e.g., antibiotics and polymers) disclosed in the present disclosure preferably have a Log P value greater than 0 and / or a P value greater than 1. Hydrophilic and / or polar compounds (e.g., antibiotics and polymers) disclosed in the present disclosure preferably have a Log P value less than 0 and / or a P value less than 1. As used in the present disclosure, "Log P" preferably refers to the n-octanol-water partition coefficient as a measure of how hydrophilic (polar) or hydrophobic (non-polar, lipophilic) a molecule / compound is. It indicates how easily a molecule / compound partitions between the aqueous and organic phases. Molecules / compounds that are more polar and hydrophilic have a lower Log P and prefer to be in the aqueous phase. More non-polar and hydrophobic molecules / compounds have a higher Log P and preferentially partition into the organic phase. Log P is equal to Log10 [Partition coefficient], where the partition coefficient (P) is equal to the quotient of the solute concentration in the organic partition divided by the solute concentration in the aqueous partition. For example, a Log P value of 1 means that the partition between the organic phase and the aqueous phase is 10:1. Those skilled in the art are familiar with the most accurate method for determining the partition coefficient (n-octanol-water) of a molecule / compound. Typically, a suitable method is the shake flask method (OECD. 107: Partition Coefficient (n-octanol / water): Shake Flask Method. OECD Guidelines for the Testing of Chemicals, 1995).

[0048] "Non-polar solvent" as used in this disclosure preferably refers to a solvent having a dipole moment less than 2.0 (Debye, D), preferably less than 1.5, a dielectric constant less than 15.0, preferably less than 5.0, and / or immiscible with water. Non-polar solvents disclosed in this disclosure are preferably one or more of chloroform, pentane, hexane, benzene, diethyl ether, 1,40-dioxane, carbon tetrachloride, methylene chloride.

[0049] As used herein, the term "polar protic solvent" refers preferably to a solvent having a dipole moment of 1.5 to 2.0 (Debye, D), a dielectric constant of more than 15.0, preferably more than 30.0, and / or miscible with water. The polar protic solvent disclosed herein is preferably one or more of water, methanol, ethanol, isopropyl alcohol, n-propanol, n-butanol, and acetic acid.

[0050] As used herein, a "polar aprotic solvent" preferably refers to a solvent having a dipole moment (Debye, D) of greater than 2.0, more preferably greater than 3.0, a dielectric constant of greater than 15.0, preferably greater than 30.0, and / or miscible with water. The polar aprotic solvent disclosed herein is preferably one or more of dimethylsulfoxide, dichloromethane, tetrahydrofuran, ethyl acetate, acetonitrile, dimethylformamide, dimethylsulfoxide, acetone, and hexamethylphosphoric triamide, more preferably dimethylsulfoxide.

[0051] Preferably, the "dipole moment" (in Debye units) disclosed in this disclosure is equal to the charge multiplied by the distance between the charges. The dipole moment of a molecule is represented by the formula (1):

number

[0052] The "dipole moments" disclosed in this disclosure may also be established experimentally.

[0053] "Dielectric constant" as used in this disclosure refers to how easily a material can be polarized by the application of an electric field to an insulator. Dielectric constant is a dimensionless variable and is defined by Equation (2):

number

[0054] The dielectric constant may vary with temperature. Preferably, the dielectric constant is established at 20-25° C. The “dielectric constant” disclosed in the present disclosure may also be established experimentally.

[0055] The term "miscible with water" as used in this disclosure means a substance (typically a liquid) that forms a homogeneous mixture when mixed with water. The miscibility of two substances is often specified optically. When two miscible liquids are combined, the resulting liquid is clear. If the mixture is cloudy, the two substances are not miscible. "Miscible" means that when a substance is mixed with water, no two layers are produced. "Immiscible" means that two layers are produced in any ratio.

[0056] In one embodiment of the method of making the antimicrobial preparation disclosed herein: - the mixture of step c) and / or the antimicrobial preparation has a dynamic viscosity of between 1 mPa·s and 20 Pa·s (Pascal-seconds), preferably between 1 mPa·s and 2 Pa·s, more preferably between 1 mPa·s and 200 mPa·s.

[0057] In the methods disclosed in the present disclosure, the mixture of step c) and / or the antimicrobial preparation may have a dynamic viscosity of at least 0.01 mPa·s, or at least 0.1 mPa·s, or at least 1 mPa·s, or at least 10 mPa·s, or at least 100 mPa·s, or at least 1 Pa·s, or at least 10 Pa·s, or at least 100 Pa·s, or at least 1000 Pa·s. Additionally or alternatively, in the methods disclosed in the present disclosure, the mixture of step c) and / or the antimicrobial preparation may have a dynamic viscosity of 1000 Pa·s or less, or 100 Pa·s or less, or 10 Pa·s or less, or 1 Pa·s or less, or 100 mPa·s or less, or 10 mPa·s or less, or 1 mPa·s or less, or 0.1 mPa·s or less, or 0.01 mPa·s or less.

[0058] The term "dynamic viscosity" as used in this disclosure refers to the internal resistance of a fluid to flow, i.e., the amount of force required to make a fluid flow. Dynamic viscosity is generally expressed in Newton-seconds per square meter (N·s / m2), Pascal-seconds (Pa·s), kilograms per meter per second (kg·m-1·s-1), or poise (P). Preferably, the dynamic viscosity disclosed in this disclosure is measured using a commercially available automated viscometer (e.g., m-VROC, RheoSense, measured using a sample volume of 100 microliters at 20-25°C).

[0059] In one embodiment, the polymer disclosed herein is a hydrophilic (polar) polymer, e.g., as disclosed herein. In one embodiment, the polymer disclosed herein is a hydrophobic (non-polar) polymer, e.g., as disclosed herein. In one embodiment, the aliphatic polyester is a hydrophobic aliphatic polyester, preferably one or more of PDLG (DL-lactide / glycolide copolymer), PLGA (L-lactide / glycolide copolymer), PLC (L-lactide / caprolactone copolymer), PCL polycaprolactone, PD [poly(D-lactide)], PL [poly(L-lactide)], or PDL [poly(DL-lactide)], more preferably PDLG.

[0060] In one embodiment, the polymer is one or more selected from the group consisting of PGA (polyglycolide), poly(ethylene glycol) (PEG), poly(propylene glycol) (PPG), PEG diacrylate (PEGDA), and PEG dimethacrylate (PEGDMA). In one embodiment, the polymer is an aliphatic polyether, such as PEG or PPG.

[0061] In one embodiment, the aliphatic polyester is neither hydrophilic (polar) nor hydrophobic (non-polar).

[0062] In one embodiment, the first antibiotic disclosed in the present disclosure is one or more of a rifamycin, a hydrophobic hydroquinolone, a macrolide, a tetracycline, or a lincosamide, preferably rifampin.

[0063] The rifamycins referred to in this disclosure are preferably one or more of rifampin, rifamycin B, rifabutin, rifapentine, and rifaximin. The "rifampin" disclosed in this disclosure is also known as rifampicin, and therefore "rifampin" may be used interchangeably with "rifampicin". The hydrophobic hydroquinolones referred to in this disclosure are preferably one or more of levofloxacin and moxifloxacin. The macrolides referred to in this disclosure are preferably one or more of erythromycin, roxithromycin, azithromycin, and clarithromycin. The tetracyclines referred to in this disclosure are preferably one or more of tetracycline, oxytetracycline, dioxycycline, tigecycline, and minocycline. The lincosamides referred to in this disclosure are preferably one or more of lincomycin, clindamycin, and pirlimycin.

[0064] In one embodiment, the second antibiotic disclosed in the present disclosure is one or more of a glycopeptide, an aminoglycoside, a β-lactam, a carbapenem, a hydrophilic fluoroquinolone, or a streptogramin, preferably vancomycin.

[0065] The aminoglycosides referred to in this disclosure are preferably one or more of tobramycin, gentamicin, neomycin, and streptomycin. The β-lactams referred to in this disclosure are preferably one or more of penicillin, cephalosporin, and piperacillin. The glycopeptides referred to in this disclosure are preferably one or more of vancomycin, teicoplanin, relavancin, and ramoplanin. The carbapenems referred to in this disclosure are preferably one or more of imipenem and meropenem. The hydrophilic fluoroquinolones referred to in this disclosure are preferably one or more of norfloxacin and ciprofloxacin. The streptogramins referred to in this disclosure are preferably one or more of pristinamycin and virginiamycin.

[0066] In one embodiment, the fluorinated solvent disclosed in the present disclosure is a fluorocarbon, a fluoroalcohol, or a mixture thereof, preferably one or more of tetrafluoroethylene, hexafluoroisopropanol, trifluoroethanol, and trifluoropropanol, more preferably tetrafluoroethylene.

[0067] In one embodiment of the method of making the antimicrobial preparation disclosed herein: the second solvent is a non-polar organic solvent, a polar aprotic organic solvent or a mixture thereof, preferably one or more of chloroform, pentane, hexane, benzene, diethyl ether and 1,40-dioxane, more preferably chloroform; and / or the third solvent is one or more polar aprotic organic solvents, preferably one or more of dimethylsulfoxide, dichloromethane, tetrahydrofuran, ethyl acetate, acetonitrile, dimethylformamide, dimethylsulfoxide, acetone, and hexamethylphosphoric triamide, more preferably dimethylsulfoxide.

[0068] In one embodiment, the first solvent disclosed herein is a polar aprotic solvent (eg, one or more of the polar aprotic solvents disclosed herein).

[0069] In one embodiment, the first solvent is a polar aprotic solvent.

[0070] In one embodiment, the first solvent is a non-polar solvent (eg, one or more of the non-polar solvents disclosed in the present disclosure).

[0071] In one embodiment of the method of making the antimicrobial preparation disclosed herein: - in step a), the polymer is present in the first solvent in a concentration of between 50 and 500 mg / ml, preferably between 100 and 300 mg / ml; - in step b) the first antibiotic is present in the second solvent in a concentration between 25 and 500 mg / ml, preferably between 50 and 350 mg / ml; - the mixing in step c) is carried out in a ratio of the second solvent containing the first antibiotic to the first solvent containing the polymer of 1:1 to 1:2.5, preferably 1:1.5 to 1:2; - in step d) the second antibiotic is present in the third solvent in a concentration between 25 and 500 mg / ml, preferably between 50 and 300 mg / ml; and / or In step e), mixing of a third solvent containing a second antibiotic with the mixture of step c) is carried out in a ratio of 1:2 to 1:7, preferably 1:3 to 1:6, more preferably 1:4 to 1:5.

[0072] In step a) of the method for producing the antimicrobial preparation disclosed in the present disclosure, the polymer may be present in the first solvent at a concentration of at least 1 mg / ml, or at least 10 mg / ml, or at least 50 mg / ml, or at least 100 mg / ml, or at least 200 mg / ml, or at least 300 mg / ml, or at least 400 mg / ml, or at least 500 mg / ml, or at least 1 g / ml, or at least 2 g / ml, or at least 5 g / ml, or at least 10 g / ml. Additionally or alternatively, the polymer may be present in the first solvent at a concentration of 10 g / ml or less, or 5 g / ml or less, or 2 g / ml or less, or 1 g / ml or less, or 500 mg / ml or less, or 400 mg / ml or less, or 300 mg / ml or less, or 200 mg / ml or less, or 100 mg / ml or less, or 50 mg / ml or less, or 10 mg / ml or less, or 1 mg / ml or less.

[0073] In step b) of the method for producing an antibacterial preparation disclosed in the present disclosure, the first antibiotic may be present in the second solvent at a concentration of at least 1 mg / ml, or at least 10 mg / ml, or at least 50 mg / ml, or at least 100 mg / ml, or at least 200 mg / ml, or at least 300 mg / ml, or at least 350 mg / ml, or at least 400 mg / ml, or at least 500 mg / ml, or at least 1 g / ml, or at least 2 g / ml, or at least 5 g / ml, or at least 10 g / ml. Additionally, or alternatively, the first antibiotic may be present in the second solvent at a concentration of 10 g / ml or less, or 5 g / ml or less, or 2 g / ml or less, or 1 g / ml or less, or 500 mg / ml or less, or 400 mg / ml or less, or 350 mg / ml or less, or 300 mg / ml or less, or 200 mg / ml or less, or 100 mg / ml or less, or 50 mg / ml or less, or 10 mg / ml or less, or 1 mg / ml or less.

[0074] In step c) of the method for producing an antimicrobial preparation disclosed in the present disclosure, the mixing in step c) of the second solvent comprising the first antibiotic with the first solvent comprising the polymer may be carried out in a ratio of at least 1:1, or at least 1:1.5, or at least 1:2, or at least 1:2.5, or at least 1:3, or at least 1:3.5, or at least 1:4, or at least 1:4.5, or at least 1:5, or at least 1:6, or at least 1:7, or at least 1:8, or at least 1:9, or at least 1:10, or at least 1:20. Additionally or alternatively, the mixing of the second solvent comprising the first antibiotic with the first solvent comprising the polymer in step c) may be performed in a ratio of 1:20 or less, or 1:10 or less, or 1:9 or less, or 1:8 or less, or 1:7 or less, or 1:6 or less, or 1:5 or less, or 1:4.5 or less, or 1:4 or less, or 1:3.5 or less, or 1:3 or less, or 1:2.5 or less, or 1:2 or less, or 1:1.5 or less, or 1:1 or less.

[0075] In step d) of the method for producing an antibacterial preparation disclosed in the present disclosure, the second antibiotic may be present in the third solvent at a concentration of at least 1 mg / ml, or at least 10 mg / ml, or at least 50 mg / ml, or at least 100 mg / ml, or at least 200 mg / ml, or at least 300 mg / ml, or at least 400 mg / ml, or at least 500 mg / ml, or at least 1 g / ml, or at least 2 g / ml, or at least 5 g / ml, or at least 10 g / ml. Additionally or alternatively, the second antibiotic may be present in the third solvent at a concentration of 10 g / ml or less, or 5 g / ml or less, or 2 g / ml or less, or 1 g / ml or less, or 500 mg / ml or less, or 400 mg / ml or less, or 300 mg / ml or less, or 200 mg / ml or less, or 100 mg / ml or less, or 50 mg / ml or less, or 10 mg / ml or less, or 1 mg / ml or less.

[0076] In step e) of the method for producing an antibacterial preparation disclosed in the present disclosure, the mixing of the third solvent containing the second antibiotic with the mixture of step c) is carried out in a proportion of at least 1 mg / ml, or at least 10 mg / ml, or at least 50 mg / ml, or at least 100 mg / ml, or at least 200 mg / ml, or at least 300 mg / ml, or at least 400 mg / ml, or at least 500 mg / ml, or at least 1 g / ml, or at least 2 g / ml, or at least 5 g / ml, or at least 10 g / ml. The mixing of the third solvent containing the second antibiotic with the mixture of step c) is carried out in a proportion of at least 10 g / ml or less, or 5 g / ml or less, or 2 g / ml or less, or 1 g / ml or less, or 500 mg / ml or less, or 400 mg / ml or less, or 300 mg / ml or less, or 200 mg / ml or less, or 100 mg / ml or less, or 50 mg / ml or less, or 10 mg / ml or less, or 1 mg / ml or less.

[0077] In one aspect, the disclosure relates to an antimicrobial preparation comprising: - a polymer in a concentration of 10-300 mg / ml of the antimicrobial preparation, preferably 50-150 mg / ml, which is an aliphatic polymer, preferably a hydrophobic aliphatic polyester, more preferably one or more of PDLG (DL-lactide / glycolide copolymer), PLGA (L-lactide / glycolide copolymer), PLC (L-lactide / caprolactone copolymer), PCL (polycaprolactone), PD [poly(D-lactide)], PL [poly(L-lactide)] or PDL [poly(DL-lactide)], most preferably PDLG; - a first antibiotic in a concentration of 10-200 mg / ml of the antibacterial preparation, preferably 20-100 mg / ml, which is soluble in a hydrophobic and / or non-polar organic solvent, preferably one or more of a rifamycin, a hydrophobic hydroquinolone, a macrolide, a tetracycline or a lincosamide, more preferably rifampin; - a second antibiotic in a concentration of 10-200 mg / ml of the antibacterial preparation, preferably 20-100 mg / ml, which is soluble in a hydrophilic and / or polar aprotic organic solvent and is preferably one or more of a glycopeptide, an aminoglycoside, a β-lactam, a carbapenem, a hydrophilic fluoroquinolone or a streptogramin, more preferably vancomycin; a non-polar organic solvent in a concentration of 10-50% (v / v), preferably 20-40% (v / v), relative to the antimicrobial preparation, preferably one or more of chloroform, pentane, hexane, benzene, diethyl ether and 1,40-dioxane, more preferably chloroform; and / or a polar aprotic organic solvent, preferably one or more of dimethyl sulfoxide, dichloromethane, tetrahydrofuran, ethyl acetate, acetonitrile, dimethylformamide, dimethyl sulfoxide, acetone and hexamethylphosphoric triamide, more preferably dimethyl sulfoxide, in a concentration of 1 to 40% (v / v) relative to the antimicrobial preparation, preferably 10 to 30% (v / v); The present invention relates to an antibacterial preparation comprising:

[0078] In the antimicrobial preparations of the present disclosure, the polymer, the first antibiotic, and / or the second antibiotic may be present in an amount of at least 1 mg / ml, or at least 10 mg / ml, or at least 50 mg / ml, or at least 100 mg / ml, or at least 200 mg / ml, or at least 300 mg / ml, or at least 350 mg / ml, or at least 400 mg / ml, or at least 500 mg / ml, or at least 1 g / ml, or at least 2 g / ml, or at least 5 g / ml, or at least 10 g / ml. Additionally or alternatively, the polymer, the first antibiotic, and / or the second antibiotic may be present in an amount of 10 g / ml or less, or 5 g / ml or less, or 2 g / ml or less, or 1 g / ml or less, or 500 mg / ml or less, or 400 mg / ml or less, or 350 mg / ml or less, or 300 mg / ml or less, or 200 mg / ml or less, or 100 mg / ml or less, or 50 mg / ml or less, or 10 mg / ml or less, or 1 mg / ml or less.

[0079] In the antimicrobial preparations of the present disclosure, the non-polar organic solvent may be present in a concentration (v / v of the antimicrobial preparation) of at least 1%, or at least 2%, or at least 5%, or at least 10%, or at least 20%, or at least 30%, or at least 40%, or at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90%. Additionally or alternatively, the non-polar organic solvent may be present in a concentration (v / v of the antimicrobial preparation) of 90% or less, or 80% or less, or 70% or less, or 60% or less, or 50% or less, or 40% or less, or 30% or less, or 20% or less, or 10% or less, or 5% or less, or 2% or less, or 1% or less.

[0080] In one embodiment, the antimicrobial preparations disclosed herein have a dynamic viscosity of 1 mPa·s to 20 Pa·s (Pascal-seconds), preferably 1 mPa·s to 2 Pa·s, and more preferably 1 mPa·s to 200 mPa·s.

[0081] The antimicrobial preparations disclosed in the present disclosure may have a dynamic viscosity of at least 0.01 mPa·s, or at least 0.1 mPa·s, or at least 1 mPa·s, or at least 10 mPa·s, or at least 100 mPa·s, or at least 1 Pa·s, or at least 10 Pa·s, or at least 100 Pa·s, or at least 1000 Pa·s. Additionally, or alternatively, the antimicrobial preparations disclosed in the present disclosure may have a dynamic viscosity of 1000 Pa·s or less, or 100 Pa·s or less, or 10 Pa·s or less, or 1 Pa·s or less, or 100 mPa·s or less, or 10 mPa·s or less, or 1 mPa·s or less, or 0.1 mPa·s or less, or 0.01 mPa·s or less.

[0082] In one aspect, the present disclosure relates to the use of an antimicrobial preparation (obtained by the method disclosed herein) for preparing an antimicrobial coating, which is preferably carried out using dip coating, spin coating, spraying, electrospinning, electrophoretic deposition, sputter coating, thermal spraying, plasma spraying, sol-gel, layer-by-layer coating, and more preferably, electrospraying.

[0083] In one aspect, the present disclosure relates to a method for producing an antimicrobial coating, the method comprising the steps of applying an antimicrobial preparation obtained by one of the various embodiments of the method for producing an antimicrobial preparation disclosed in the present disclosure to a substrate, and removing one or more solvents in the antimicrobial preparation. In the method for producing an antimicrobial coating in the present disclosure, the application is preferably performed using dip coating, spin coating, spraying, electrospinning, electrophoretic deposition, sputter coating, thermal spraying, plasma spraying, sol-gel, layer-by-layer coating, more preferably electrospraying.

[0084] The term "electrospray" disclosed in this disclosure relates to a method of depositing a liquid (e.g., an antimicrobial preparation) onto a substrate using electrostatic forces and surface tension to generate one or more generations of charged monodisperse droplets that are directed toward the substrate. Typically, electrospray uses a high voltage power supply, a container (e.g., a syringe) capped with a metal capillary to hold the liquid, a pump to control the flow of the liquid, and a grounded collector (e.g., a metal substrate). When a high electric field is applied to the needle, the charged liquid jet breaks into droplets. At the tip of the nozzle, the charged solution can break into microscale droplets. Furthermore, child droplets can be formed that have a large surface area compared to their volume. This process can occur multiple times depending on the spray distance and solution composition, resulting in the generation of several generations of monodisperse droplets, most typically two generations. This ultimately forms small particles with a generally narrow particle size distribution on the collector. The "electrospray" disclosed in this disclosure can be used interchangeably with "electrospray deposition" or "electrodynamic spray". Those of skill in the art are familiar with variations of electrospray technology and its applications (e.g., Wang et al., Electrospraying: Possibilities and Challenges of Engineering Carriers for Medical Applications—A Mini Review. Front. Chem., 25 April 2019).

[0085] Preferably, the electrospray method disclosed herein comprises: The antibacterial preparation is injected into a syringe (e.g., 3 mL-5 mL) equipped with a needle (e.g., steel). A voltage is applied between the needle and the metal object to be coated to create the required electric field. The voltage is preferably 10-30 kV (e.g., 16 kV). The coating solution is delivered through the syringe needle (e.g., using a syringe pump) at a flow rate of preferably 0.1-1 ml / h (e.g., 0.5 ml / h). The electrosprayed droplets are deposited on the (metal) coating object, which is placed at a suitable distance, preferably 5-15 cm (e.g., 8 cm), from the tip of the needle. The coated object may be further treated (e.g., by keeping in a vacuum with a cold trap, liquid nitrogen) to remove the organic solvent, or using similar methods.

[0086] The "substrate" disclosed in this disclosure may be a metal, polymer, glass, bioglass, and / or elastomer, preferably a metal, more preferably a stainless steel (e.g., surgical grade stainless steel such as 316L), a cobalt chromium (Co-Cr) alloy, pure commercial titanium (Ti), or a Ti alloy. The substrate is preferably a surface of a medical device. The "medical device" disclosed in this disclosure is typically a device that can be inserted or is designed to be inserted into a subject's body as part of a medical diagnosis and / or treatment. The medical device may be degradable or non-degradable. Common examples of medical devices include: stents, catheters, pacemakers, implantable cardioverter defibrillators, coronary stents, degradable grafts, Eustachian tubes, interocular lenses, implantable insulin pumps, intrauterine devices, surgical mesh implants, breast implants, orthopedic implants, and artificial joints. As used in this disclosure, the term "medical device" may be used interchangeably with "biomedical device," "implantable device," "implant," or "(biomedical) implant."

[0087] The "removal" of solvent in a material disclosed in the present disclosure (e.g., in an antimicrobial preparation or in an antimicrobial coating) may include any method that reduces the amount of solvent in the material to a particular level. The removal of the solvent is preferably performed by evaporating the solvent. A preferred method of evaporation includes leaving the material at room temperature (20-22°C) until the amount of residual solvent in the material is reduced to a particular level. Another preferred method is drying the material at an elevated temperature (e.g., 22-50°C) until the amount of solvent in the material is reduced to a particular level. Additionally or alternatively, for example, the material may be placed in a compressed gas (argon, nitrogen, helium, air, etc.) to aid in the evaporation of the solvent until the amount of solvent in the material is reduced to a particular level. The particular level of residual solvent is typically a level at which the solvent is considered safe and has no harmful effects on the human body. Those skilled in the art are well aware that the amount of residual solvent that is acceptable in a material for use in the human body depends on the type of solvent and the therapeutic use of the material carrying the residual solvent.

[0088] In one aspect, the present disclosure relates to an antimicrobial coating comprising: a polymer in an amount of 40-90% by weight, preferably 50-80% by weight, relative to the antimicrobial coating, which polymer is an aliphatic polyester, preferably a hydrophobic aliphatic polyester; a first antibiotic in an amount of 5-40% by weight, preferably 10-30% by weight, relative to the antimicrobial coating, the first antibiotic being soluble in a hydrophobic and / or non-polar organic solvent; and a second antibiotic in an amount of 5-40% by weight, preferably 10-30% by weight, relative to the antimicrobial coating, the second antibiotic being hydrophilic and / or soluble in polar aprotic organic solvents, Including, The disclosure relates to an antimicrobial coating in which a first antibiotic and a second antibiotic are contained in a matrix that is acted upon by the polymer.

[0089] In the antimicrobial coatings disclosed herein, the polymer, the first antibiotic, and / or the second antibiotic may be (independently) present in an amount of at least 1%, or at least 5%, or at least 10%, or at least 20%, or at least 30%, or at least 40%, or at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90% (by weight of the antimicrobial coating). Additionally or alternatively, the polymer, the first antibiotic, and / or the second antibiotic may be (independently) present in an amount of 90% or less, or 80% or less, or 70% or less, or 60% or less, or 50% or less, or 40% or less, or 30% or less, or 20% or less, or 10% or less, or 5% or less, or 1% or less (by weight of the antimicrobial coating).

[0090] In one embodiment of the antimicrobial coating disclosed in the present disclosure: the aliphatic polyester is one or more of PDLG (DL-lactide / glycolide copolymer), PLGA (L-lactide / glycolide copolymer), PLC (L-lactide / caprolactone copolymer), PCL polycaprolactone, PD [poly(D-lactide)], PL [poly(L-lactide)] or PDL [poly(DL-lactide)], preferably PDLG; - First-line antibiotics are rifamycins, hydrophobic hydroquinolones, macrolides one or more of a tetracycline or a lincosamide, preferably rifampin; and / or the second antibiotic is one or more of a glycopeptide, an aminoglycoside, a β-lactam, a carbapenem, a hydrophilic fluoroquinolone, or a streptogramin, preferably vancomycin.

[0091] In one embodiment of the antimicrobial coating disclosed in the present disclosure: - the antibacterial coating is a single layer antibacterial coating, preferably with a thickness of 10-1000 μm, more preferably 50-500 μm, even more preferably 100-250 μm; the total polymer content in the antimicrobial coating is 90-100% by weight, preferably 95-100% by weight, more preferably 99-100% by weight, most preferably 100% by weight, of a single polymer; and / or - the surface of the antimicrobial coating is hydrophobic, as defined by a static water contact angle of 70° or more, preferably 80° or more, more preferably 90° or more; and / or The antibacterial coating has an average surface roughness of 20 to 1000 nm, preferably 20 to 500 nm (for example 50 to 400 nm, or 100 to 300 nm), more preferably 20 to 200 nm.

[0092] The antimicrobial coatings disclosed in the present disclosure may have a thickness of at least 1 μm, or at least 5 μm, or at least 10 μm, or at least 20 μm, or at least 30 μm, or at least 40 μm, or at least 50 μm, or at least 60 μm, or at least 70 μm, or at least 80 μm, or at least 90 μm, or at least 100 μm, or at least 200 μm, or at least 300 μm, or at least 400 μm, or at least 500 μm, or at least 600 μm, or at least 700 μm, or at least 800 μm, or at least 900 μm, or at least 1000 μm, or at least 2000 μm, or at least 3000 μm, or at least 4000 μm, or at least 5000 μm. Additionally or alternatively, the antimicrobial coatings disclosed in the present disclosure may have a thickness of 5000 μm or less, or 4000 μm or less, or 3000 μm or less, or 2000 μm or less, or 1000 μm or less, or 900 μm or less, or 800 μm or less, or 700 μm or less, or 600 μm or less, or 500 μm or less, or 400 μm or less, or 300 μm or less, or 200 μm or less, or 100 μm or less, or 90 μm or less, or 80 μm or less, or 70 μm or less, or 60 μm or less, or 50 μm or less, or 40 μm or less, or 30 μm or less, or 20 μm or less, or 10 μm or less, or 5 μm or less, or 1 μm or less.

[0093] The "thickness" of the antimicrobial coatings disclosed in this disclosure refers to an average thickness, e.g., at least 1 mm. 2 , preferably at least 1 cm 2The term "antimicrobial coating thickness" refers to the average thickness determined from the antimicrobial coating of the present disclosure. The average thickness may be based on sufficient measurements performed on (a portion of) the sample such that the standard deviation is 20% or less. The thickness of the antimicrobial coating disclosed in this disclosure is preferably measured by spectroscopic reflectance. Spectroscopic reflectance typically measures the amount of light reflected from a thin film over a range of wavelengths, with the incident light perpendicular to the sample surface. In a preferred method, the thickness of the coating is measured using a Filmetrics thin film measurement system (e.g., F40, Filmetrics Europe GmbH, or similar) set up on an incident light microscope using a wavelength range of 400-850 nm. The optical refractive index is preferably assumed to be n=1.5.

[0094] The term "roughness" as used in this disclosure refers to the roughness of the coating. "Roughness" is preferably a term that refers to the average roughness (e.g., based on measurements that are performed sufficiently such that the standard deviation is 20% or less). The roughness of the antimicrobial coatings disclosed in this disclosure is preferably measured using an atomic force microscope (AFM). In a preferred method, the surface roughness is measured using an atomic force microscope (AFM, EasyScan, or similar) while recording in tapping mode at room temperature in the presence of air.

[0095] The inventors have discovered that the antimicrobial preparations of the present invention allow the formation of coatings with no or reduced porosity, i.e. reduced pore size and / or reduced pore diameter. Coatings with no apparent porosity could be achieved.

[0096] In one embodiment, the antimicrobial coating has a density and morphology that can be defined by the porosity disclosed herein.

[0097] The low / no porosity of the coating allows it to: - Antibiotic release, e.g. more sustained release of antibiotics; - More uniform coating - Fewer air pockets - Stronger adhesion to the implant material, e.g. improving detachment during implantation; - Thinner coatings, which make implantation easier, for example; - Improved cell adhesion; - Higher drug loading (concentration); - Higher polymer loading (concentration) This can provide one or more advantages.

[0098] In one preferred embodiment, the antimicrobial coating disclosed in the present disclosure comprises: - 20% or less, or 10% or less, or 1% or less, or 0.1% or less porosity; and / or - pore size of 1 μm or less, preferably 0.1 μm or less, more preferably 0.01 μm or less has.

[0099] wherein the antibacterial preparation is obtained by the methods disclosed in the present disclosure.

[0100] In a preferred embodiment, the antimicrobial coatings disclosed in the present disclosure are free of porosity.

[0101] The term "porosity" of a coating as used in this disclosure refers to the ratio of the volume of the (solid) coating-free portion (e.g., voids or cavities formed by air or other gases) to the total volume of the coating. Porosity is typically expressed as a percentage of the volume ranging from 0 to 1, or a percentage ranging from 0 to 100%. In the context of the present invention, porosity is preferably expressed as a percentage (%). The skilled artisan will be familiar with several methods for measuring the porosity of a material. Preferred methods for measuring porosity (or pore size) include mercury porosimetry, liquid intrusion, gravimetry, and microscopy (e.g., confocal laser scanning microscopy, confocal laser scanning microscopy, scanning electron microscopy). Preferred methods for measuring porosity (or pore size) by liquid intrusion, gravimetry, and scanning electron microscopy (SEM) are given by Soliman et al. (Acta Biomaterialia 6 (2010) 1227-1237). In a preferred liquid intrusion method, the coated sample is dissolved in ethanol (density ρ EtOH The specimen is weighed before immersion in a 1000 ml ethanol solution (V = 0.789 g / ml of the porosity liquid), left on a shaker table overnight to allow the ethanol to diffuse into the void volume, then blotted with a Kimwipe and reweighed. Porosity is the volume of ethanol that has penetrated, V EtOH Dividing by the total volume after penetration gives ε = V EtOH / (V EtOH + V coating ) In the preferred gravimetric method, porosity is calculated as ε = 1ρ APP / ρ PCL where the apparent coating density ρ APPis measured as a mass / volume ratio. In the preferred SEM method, porosity ε=VF is determined as the average projected porosity inferred from the porosity percent VF seen in a top-view SEM micrograph of the sample. Percent VF is determined by counting and summing through voids in a two-dimensional SEM image. For example, a Matlab (MathWorks Inc.) script can be used to convert the grayscale image to black and white format and calculate the porosity (i.e., percentage of white pixels) in an automated manner. The term "porosity" as used in this disclosure is preferably defined as the average porosity of 0.5 cm 2 of coating surface area and / or average porosity as specified for a coating thickness of 100 μm or as determined for a dry weight of ∼50 mg of coating.

[0102] - The term "pore size" as used in this disclosure refers to the diameter of the pores of a porous structure, for example of a polymer coating. There is no univocal definition of pore size, as it varies depending on the measurement technique and whether it is evaluated using a two-dimensional or three-dimensional approach (Bartos et al. Biomed Eng Online. 2018 Aug 17;17(1):110). The pore size referred to in this disclosure is determined by scanning electron microscopy (SEM), for example, by the average value of the following image analysis software (for example, using the manual mode of the freeware ImageJ software from the National Institutes of Health): 40 pores per two perpencidular sections are evaluated, and each perpencidular section is repeated for a total of four SEM micrographs (taken at 100x). Randomly selected pores are analyzed for their major axis (the longest distance from wall to wall across the pore) and minor axis (the shortest distance from wall to wall across the pore). The average of the major and minor axes determines the pore size. The "pore size" used in this disclosure is preferably, for example, 0.5 cm 2and / or the average pore size specified for a coating surface area of ​​100 μm, or for a coating thickness of ∼50 mg dry weight of coating. The term "pore size" in the context of the present invention can be used interchangeably with the term "pore size".

[0103] In one embodiment, the antimicrobial coating disclosed in the present disclosure has a porosity of 75% or less, or 70% or less, or 65% or less, or 60% or less, or 55% or less, or 50% or less, or 45% or less, or 40% or less, or 35% or less, or 30% or less, or 25% or less, or 20% or less, or 15% or less, or 10% or less, or 5% or less, or 1% or less, or 0.5% or less, or 0.1% or less, or 0.05% or less, or 0.01% or less, or 0.001% or less. Preferably, the antimicrobial coating disclosed in the present disclosure has a porosity of 0.0001% to 10%, more preferably 0.001 to 1%, and even more preferably 0.01 to 0.1%. In one embodiment, the antimicrobial coating disclosed in the present disclosure has no porosity (i.e., 0%).

[0104] In one embodiment, the antimicrobial coating disclosed in the present disclosure has an average pore size of 100 μm or less, or 50 μm or less, or 25 μm or less, or 10 μm or less, or 5 μm or less, or 1 μm or less, or 0.5 μm (500 nm) or less, or 0.4 μm (400 nm) or less, or 0.3 μm (300 nm) or less, or 0.2 μm (200 nm) or less, or 0.1 μm (100 nm) or less, or 0.05 μm (50 nm) or less, or 0.01 μm (10 nm) or less, or 0.001 μm (1 nm) or less. Preferably, the antimicrobial coating disclosed in the present disclosure has a pore size of 0.00001-1 μm, more preferably 0.0001-0.1 μm, more preferably 0.001-0.01 μm 0.1%. In one embodiment, the antimicrobial coating disclosed in the present disclosure has no pore size (0 μm).

[0105] In one aspect, the present disclosure provides a method for the treatment and / or prevention of medical device-associated infections, preferably for the treatment and / or prevention of orthopedic implant-associated infections. An antibacterial preparation obtained by the method disclosed in the present disclosure; The antimicrobial coating disclosed herein, and / or Antimicrobial coating obtained by the method disclosed in the present disclosure Regarding.

[0106] The antimicrobial preparation is preferably an antimicrobial preparation obtained / obtained by a method disclosed in the present disclosure.The antimicrobial coating is preferably an antimicrobial coating obtained / obtained by coating with an antimicrobial preparation disclosed in the present disclosure.

[0107] The "infections associated with medical devices" and / or "infections associated with orthopedic implants" disclosed in this disclosure are preferably infections caused by microorganisms, typically yeasts (e.g., Candida albicans), or bacteria such as Staphylococcus ssp. (e.g., Staphylococcus aureus, Staphylococcus epidermidis), Streptococcus ssp. (e.g., Streptococcus bovis), Enterococcus ssp., and (other) gram-negative bacteria such as Klebsiella, Enterobacter, Acinetobacter, Pseudomonas, and Escherichia ssp. The infections associated with medical devices and / or orthopedic implants disclosed in this disclosure may be infections caused by antibiotic-resistant strains such as vancomycin-resistant Enterococcus, methicillin-resistant Staphylococcus aureus, methicillin-resistant Staphylococcus epidermidis, and multidrug-resistant gram-negative bacteria. The infection in a "medical device associated infection" and / or an "orthopedic implant associated infection" may be present on the surface of the medical device / implant, typically in the form of a biofilm. Additionally or alternatively, the infection may be present in the tissue surrounding the medical device / implant. A "medical device associated infection" and / or an "orthopedic implant associated infection" may be the result of a surgical procedure (e.g., an open wound through which microorganisms can enter the body) and / or the presence of the medical device / implant in the body (e.g., microorganisms may adhere to the medical device / implant, tissue damage, and / or a change in the immune response, making the microorganism more likely to survive in the tissue surrounding the medical device / implant).

[0108] The "orthopedic implant" disclosed in the present disclosure may be one or more of a prosthesis, a bone screw, a bone pin, a hook, a rod, a bone substitute, an internal fixator, an external fixator, an intramedullary nail, a K-wire, a spacer, a cage, an artificial frame, an anchor, a joint nail, and a bone plate. The orthopedic implant of the present technology may include a solid metal, such as gold, silver, stainless steel, platinum, palladium, iridium, iron, nickel, copper, titanium, aluminum, chromium, cobalt, molybdenum, vanadium, tantalum, and alloys thereof. In a preferred embodiment, the orthopedic implant includes a metal, including surgical stainless steel, titanium, and / or titanium alloys. The orthopedic implant may be a solid implant or a (partially) porous implant, manufactured, for example, by selective laser melting, metal 3D printing, direct metal laser sintering, and / or additive manufacture.

[0109] As used herein, an "orthopedic implant-associated infection" may be an infection that is newly established in a subject, i.e., the subject did not have an infection or was not previously diagnosed with an infection. An "orthopedic implant-associated infection" may also be an infection that is unsuccessful in treating with systemic antibiotics alone or other therapies, necessitating a revision surgery. For example, prevention and / or treatment of an orthopedic implant-associated infection may be part of a revision surgery in which the original implant is removed and a new implant (preferably including an antimicrobial coating as disclosed herein) is introduced. The revision surgery may be a one-stage or two-stage surgery. In a one-stage revision surgery, typically, the infected orthopedic implant is removed, the infected site is irrigated, and a new orthopedic implant is inserted. In a two-stage revision surgery, typically, a first surgery is performed to remove the infected orthopedic implant and implant a spacer loaded with antibiotics. The spacer is usually left in the subject for several weeks (e.g., 4-8 weeks, usually 6 weeks), during which time the subject may receive systemic antibiotics. After the infection has subsided, a second surgery is performed, the spacer is removed, and a new orthopedic implant is introduced. The antimicrobial coatings disclosed in this disclosure may be present on the orthopedic implant as part of the primary surgery (where the patient has not yet contracted an infection), as part of a one-stage revision surgery, and / or as part of a two-stage revision surgery. In one embodiment, the antimicrobial coating is present on the surface of the spacer used, for example, in a two-stage revision surgery. As such, the term "implant" may be used interchangeably with "spacer."

[0110] In one embodiment of the antimicrobial coating disclosed in the present disclosure: the amount of the first and second antibiotics is, in total, from 20% to 60% by weight, preferably from 30% to 50% by weight, based on the weight of the antimicrobial coating; and / or The ratio of the sum of the first and second antibiotics to the polymer is 1:1 to 1:3, and preferably 1:1.5 to 2.5.

[0111] In the antimicrobial coatings disclosed herein, the ratio of the sum of the first and second antibiotics to the polymer is at least 1:1, or at least 1:1.5, or at least 1:2, or at least 1:2.5, or at least 1:3, or at least 1:3.5, or at least 1:4, or at least 1:4.5, or at least 1:5, or at least 1:6, or at least 1:7, or at least 1:8, or at least 1:9, or at least 1:10, or at least 1:20. Additionally or alternatively, the ratio of the sum of the first and second antibiotics to the polymer is 1:20 or less, or 1:10 or less, or 1:9 or less, or 1:8 or less, or 1:7 or less, or 1:6 or less, or 1:5 or less, or 1:4.5 or less, or 1:4 or less, or 1:3.5 or less, or 1:3 or less, or 1:2.5 or less, or 1:2 or less, or 1:1.5 or less, or 1:1 or less.

[0112] In the antimicrobial coatings disclosed in the present disclosure, the total amount of the first and second antibiotics (by weight of the antimicrobial coating) may be as follows:

[0113] In one aspect, the present disclosure provides the use of an antibiotic and / or a solvent as a dynamic viscosity reducing agent in the preparation of an antimicrobial preparation, comprising: the antibiotic is preferably hydrophobic and / or soluble in a preferably non-polar organic solvent, preferably one or more of a rifamycin, a hydrophobic hydroquinolone, a macrolide, a tetracycline, or a lincosamide, more preferably rifampin; the solvent is preferably a non-polar organic solvent, more preferably one or more of chloroform, pentane, hexane, benzene, diethyl ether and 1,40-dioxane, more preferably chloroform; and / or the antimicrobial preparation is preferably for use as a coating preparation, more preferably in dip-coating, spin-coating, spraying, electrospinning, electrophoretic deposition, sputter-coating, thermal spraying, plasma spraying, sol-gel, layer-by-layer coating, most preferably in electrospraying, Regarding use.

[0114] Additionally or alternatively, the use of the antibiotics and / or solvents disclosed herein may: a first antibiotic, preferably hydrophobic and / or soluble in a preferably non-polar organic solvent, preferably one or more of a rifamycin, a hydrophobic hydroquinolone, a macrolide, a tetracycline, a lincosamide, more preferably rifampin; and a second antibiotic, preferably hydrophilic and / or soluble in a polar aprotic organic solvent, preferably one or more of a glycopeptide, an aminoglycoside, a β-lactam, a carbapenem, a hydrophilic fluoroquinolone, or a streptogramin, more preferably vancomycin; may include:

[0115] As used in this disclosure, the terms "comprise" or "to comprise" and their conjugations are terms that refer to a situation in which the term is used in an open-ended sense, meaning that items following the term are included, but items not specifically mentioned are not excluded. Furthermore, it encompasses the more restrictive verbs "to consist essentially of" and "to consist of."

[0116] The reference to an element by the indefinite article "a" or "an" does not exclude the possibility of there being more than one of that element, unless the context makes clear that there is only one and only one is required. Thus, the indefinite article "a" or "an" normally means "at least one".

[0117] The terms "increase" and "increased level" and "decrease" and "decreased level" refer to the ability to significantly increase or decrease, or to a significantly increased or decreased level. Generally, a level is said to be increased or decreased when it is at least 5%, e.g., 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, respectively, greater or less than the corresponding level in a control or reference. Alternatively, a level in a sample may be increased or decreased when it is statistically significantly increased or decreased compared to the level in a control or reference. EXAMPLES

[0118] Example 1 1. Purpose The aim of this study was to determine the parameters required for the preparation of antibacterial coatings, where the coatings are preferably 1) be easily adaptable to incorporate multiple different antibiotics of choice (preferably a combination of hydrophobic / non-polar and hydrophilic / polar drugs); 2) can be applied as a thin coating of a single polymer; 3) high drug loadings can be incorporated; and 4) Has a low enough viscosity to be applied by a variety of coating techniques, including electrospray It has the following characteristics:

[0119] A common method for the production of antibacterial coatings is: 1. Dissolving a resorbable polymer and an antibiotic in a suitable solvent; 2. mixing the polymer solution with the antibiotic solution to obtain a polymer-antibiotic solution; 3. applying the polymer-antibiotic solution as a coating onto the medical device; 4. Evaporation of the solvent This is carried out in the following steps.

[0120] Main parameters: - Solvent properties (e.g. non-polar vs. polar organic solvents), - antibiotic properties (e.g. hydrophobic / non-polar vs. hydrophilic / polar antibiotics), - the order in which the polymer solution, the first antibiotic solution, and the second antibiotic solution are mixed; - the properties of the resorbable polymer (e.g. polyester vs. non-polyester), - Optimal drug / polymer concentration and ratio and the combinations were evaluated to investigate the effectiveness of the coating solvent on coatability, drug release profile, and antibacterial efficacy.

[0121] Drug solubility and viscosity were used as the main criteria to characterize the coatability of various coating solutions. Electrospray was selected as the preferred coating method because it is a technically challenging method that generally requires a coating solution with a low viscosity compared to other coating methods.

[0122] 2. Method 2.1. Chemicals [ka]

[0123] 2.2. Preparation of antibacterial preparations All the following steps were carried out in a fume hood at room temperature. 1. A polymer solution (solution A) was prepared by dissolving an aliphatic polyester in tetrafluoroethylene (TFE, Sigma, Germany) with stirring for 12 hours to a concentration of 200 mg / ml. 2. A first antibiotic solution (solution B) was prepared by dissolving a first antibiotic (hydrophilic or hydrophobic) in chloroform (VFE, France) or dimethyl sulfoxide (DMSO, Merck, Germany) with stirring to a concentration of 50-250 mg / ml. 3. The viscosity-reducing agent-polymer solution (solution C) was prepared by adding solution B dropwise to solution A at a ratio of 30-40% (v / v) and stirring the mixture for 6 hours. 4. A second antibiotic solution (solution D) was prepared by dissolving a second antibiotic (hydrophilic) in dimethyl sulfoxide with stirring at 40°C to a concentration of 50-250 mg / ml. 5. The coating solution (Solution E) was prepared by adding Solution D dropwise to Solution C at a ratio of 15-20% (v / v) while stirring for 24 hours.

[0124] 2.3.Coating Titanium discs (8 mm diameter, 4 mm height) were fabricated from commercially pure titanium (CP-Ti) powder (Grade 1, medical grade quality, LPW, UK). The titanium discs had coatings applied by electrospraying, electrospinning, or spin coating.

[0125] Electrospraying and electrospinning involved a home-made uniaxial solution electrospinning system. Briefly, the drug-polymer solution was loaded into a 3 ml syringe equipped with a 27-gauge (G) needle. A voltage of 16–20 kV (Heinzinger, Germany) was applied between the needle and the implant. A syringe pump (World precision instruments, US) was used to inject through the needle at a flow rate of 0.5–1 ml / h. The polymer solution was sprayed directly onto the implant, which was placed at a distance of 8 cm from the needle. The coated implant was placed under vacuum with a cold trap (liquid nitrogen) for 3 days to remove all organic solvents.

[0126] The spin-coating process was carried out at various spin speeds using a spin coater (450 SPIN COATER, Netherlands) ranging from 200 to 600 rpm at room temperature. In all coating experiments, a volume of 20 μl of the final solution was dropped onto the center of the implant before the spinning process started. The spinner was then turned on to create a layer of coating on the implant surface. This process was continued until the desired coating was formed. After coating, the samples were dried under vacuum for 3 days.

[0127] The different coating methods were found to result in a total coating deposition of 5–15 mg, determined by weighing the disks before and after coating.

[0128] 2.4. Viscosity Measurement The dynamic viscosity of the antibacterial preparation was measured using an m-VROC viscometer (Rheo Sence).

[0129] 2.5. Drug release characteristics Antibiotic release kinetics was characterized by incubating the implants in PBS (ph 7.4) at 37°C. Supernatants were removed on the indicated days and stored at -20°C until analysis. Drug concentrations in the released fluid were measured using an ACQUITY ssUPLC H-Class PLUS Bio System (Waters Corporation, US) equipped with a BEH C18 column (1.7 μm, 2.1 mm × 50 mm) and a Waters 2996 PDA detector. Drug concentrations were quantified using wavelengths for vancomycin (233 nm) and rifampin (264 nm) and normalized against calibration curves obtained by diluting stock solutions of Rif (1 mg / ml in ACN) and Van (1 mg / ml in MQ) in PBS.

[0130] 2.6. Zone of Inhibition The implants were incubated at 37°C in PBS for 4 or 6 weeks to allow the antibiotic to elute. The presence and amount of drug elution at 4 and 6 weeks was measured using bacterial growth inhibition zones. Finally, the implants were incubated at OD 200 for 12 hours to allow bacterial colonization. 600 =0.01(about 10 7 The bacteria were placed on trypticase agar plates inoculated with 0.5 ml of a bacterial suspension prepared at 100 CFU / ml. After 24 hours at 37°C, the zone of inhibition of the bacteria (expressed in cm) was measured.

[0131] 3.Results 3.1. Coating properties of different antibacterial preparations The suitability of various (multi-drug) coating solutions to form thin coatings performed by electrospraying was identified. The presence of hydrophobic antibiotics (rifampicin, erythromycin, minocycline) and / or a non-polar solvent (chloroform) was found to be important to obtain a uniform and low-viscosity solution (Table 1). Coating preparations lacking hydrophobic antibiotics and non-polar solvents (the bottom three rows in Table 1) could not be coated due to lack of drug solubility and excessively high viscosity. Thus, it was demonstrated that hydrophobic antibiotics and / or non-polar solvents have a viscosity-lowering effect.

[0132] Hydrophobic antibiotics (rifampicin, erythromycin, minocycline) can be dissolved in either non-polar (chloroform) or polar (dimethyl sulfoxide, DMSO) solvents to obtain suitable coating solutions (Table 1). Therefore, the viscosity-reducing effect of hydrophobic antibiotics may not depend on the solvent in which they are dissolved.

[0133] The order of mixing the polymer solution and the antibiotic solution was important to achieve a low viscosity coating solution. That is, mixing the polymer solution with a hydrophobic antibiotic and / or a non-polar solvent resulted in a polymer solution with a low viscosity that was maintained when subsequently mixed with a hydrophilic antibacterial solution (e.g., containing tobramycin, gentamicin, vancomycin). In contrast, no viscosity reduction effect was observed when the polymer solution was first mixed with a hydrophilic antibiotic and / or a polar solvent. Thus, a low viscosity polymer solution or a low viscosity coating solution was not obtained. Rather, the high viscosity solution obtained by combining with a hydrophilic antibiotic could not be coated.

[0134] Table 1: Suitability of different coating solutions in forming thin film coatings on substrate surfaces as determined by drug solubility and solution viscosity. A solution of antibiotic A in solvent A was first mixed with a solution of PDLG in TFE. This mixture was then mixed with a solution of antibiotic B in solvent B. Preparations containing a hydrophobic antibiotic as the first solvent and / or a non-polar solvent (mixed with the drug-polymer solution) showed superior coating properties regardless of the hydrophobic / hydrophilic drug combination (Groups 1-12). Preparations lacking a hydrophobic antibiotic as the first solvent and / or a non-polar solvent (mixed with the drug-polymer solution) were shown to be uncoatable. [Table 1]

[0135] 3.2. Coating properties of antibacterial preparations with different polymers All the (hydrophobic) aliphatic polyesters tested (PDLG, PLC, PLDL, PCL, PL) were found to be suitable as carrier materials for the antimicrobial coating (Table 2). In contrast, (hydrophilic) polyethers, such as poly(ethylene glycol), did not show any viscosity-reducing effect. Thus, the viscosity-reducing effect of hydrophobic antibiotics (rifampicin, erythromycin, minocycline) was achieved, especially when combined with (hydrophobic) aliphatic polyesters.

[0136] Table 2: The effect of the hydrophilicity / polarity of the resorbable polymer on the preparation of a coating solution suitable for forming a thin coating on the surface of a substrate, as determined by the drug solubility and viscosity of the solution. Formulations containing aliphatic polyesters (mixed with hydrophobic antibiotics and / or non-polar solvents) showed excellent coating properties (Groups 1-5). Formulations containing hydrophilic polyethers mixed with hydrophobic antibiotics and / or non-polar solvents could not be coated (Group 6). DMSO: dimethyl sulfoxide, PDLG: DL-lactide / glycolide copolymer, PLC: L-lactide / caprolactone copolymer, PLDL: L-lactide / DL-lactide copolymer, PCL: polycaprolactone, PL: poly(L-lactide). [Table 2]

[0137] 3.3. Drug release characteristics Drug release profiles demonstrated sustained release of rifampicin (Figure 1) and vancomycin (Figure 2) in coatings obtained from low-viscosity coating solutions containing at least a hydrophobic antibiotic (rifampicin) or a non-polar solvent (chloroform). These coatings demonstrated drug release above the minimum inhibitory concentration (MIC) of Staphylococcus aureus for up to 6 weeks. Aliphatic polyester (co)polymers with different properties in the coating solutions also showed similar drug release profiles (Figures 3 and 4). This further supported the possibility that aliphatic polyester polymers could contribute to the viscosity-lowering effect and high drug loading.

[0138] 3.4. Role of Viscosity in Coatability with Different Technologies It was found that the viscosity of the antimicrobial formulation influences the coating technique used for application. Electrospinning was found to be optimal for antimicrobial formulations with viscosities between 1 and 200 poise (0.1-20 Pa·s). In this viscosity range, the initial jet may not break up into individual droplets. Rather, the solvent may evaporate leaving behind polymer fibers as the jet progresses toward the target. It was found that at lower viscosities (e.g., 1-100 mPa·s), surface tension may dominate the formation of fibers, forming droplets rather than fibers. Thus, electrospraying was possible for antimicrobial formulation viscosities between 1 and 100 mPa·s. It was found that spin coating could be performed over a relatively wide viscosity range.

[0139] Sustained drug release characteristics were observed for low viscosity coating solutions applied as coatings by different technological approaches, e.g., spraying (electrospraying), spin-coating, or electrospinning (Figures 5 and 6). This highlights the potential of the hydrophobic antibiotic and / or the viscosity-reducing effect of the non-polar solvent to enable the use of different manufacturing techniques and thus to realize a variety of therapeutic applications.

[0140] 3.5. Interaction between Hydrophobic and Hydrophilic Antibiotics in Drug Release It was discovered that interactions between hydrophilic and hydrophobic antibiotics in the coating could allow for sustained drug release. A relatively high burst release was observed for coatings containing either rifampicin or vancomycin alone, whereas the combination of rifampicin and vancomycin resulted in a more sustained drug release. As a result, the release profile of both drugs is equivalent, presumably more effective at eradicating infection (sterilization).

[0141] Unexpectedly, the inventors have discovered that a hydrophilic antibiotic (e.g., vancomycin) can enhance the diffusion of a hydrophobic antibiotic (e.g., rifampicin) from a polymer matrix. Meanwhile, they have also discovered that rifampicin can retard the diffusion of vancomycin. As a result, the release profile of both drugs is comparable and more effective at eradicating the infection. In this particular experiment, PLDG was dissolved to a concentration of 200 mg / ml (Solution A), rifampicin was dissolved to a concentration of 50-70 mg / ml (Solution B), and vancomycin was dissolved to a concentration of 50-70 mg / ml (Solution D).

[0142] 3.6. Improved antibacterial effect of coatings The long-term antibacterial effect of the coatings obtained with low viscosity coating solutions showed inhibition of the growth of Staphylococcus aureus (the most common causative agent of metallic implant infections) by the growth inhibition zone approach. Antibacterial activity was observed even at the 4th and 6th week for coatings based on low viscosity coating solutions, i.e. solutions with hydrophobic antibiotics and / or non-polar solvents (Table 3). It was observed that the long-term antibacterial activity of the coatings was independent of the aliphatic polyester used (Table 4). Furthermore, long-term antibacterial activity of the coatings was observed for all hydrophilic-hydrophobic drug combinations tested (Table 5).

[0143] Table 2: Antibacterial efficacy of coated implants against Staphylococcus aureus Coatings made using coating solutions containing a hydrophobic antibiotic as the first solvent and a non-polar solvent (mixed with the drug-polymer solution) showed antimicrobial activity with a zone of inhibition of microbial growth for at least six weeks. In this experiment, PDLG (DL-lactide / glycolide copolymer) dissolved in TFE (tetrafluoroethylene) was used as the polymer solution. Coating was performed by electrospraying. # Coatings made by electrospraying were inhomogeneous. [Table 3]

[0144] Table 4: Antibacterial efficacy of coated implants against Staphylococcus aureus Coatings made with a coating solution containing an aliphatic polyester (dissolved in tetrafluoroethylene) showed antimicrobial activity with a zone of inhibition of microbial growth for at least six weeks. The coating solution further contained rifampicin / chloroform as the first antibiotic solution and vancomycin / dimethylsulfoxide as the second antibiotic solution. Coatings were applied by electrospray. PDLG: DL-lactide / glycolide copolymer, PLC: L-lactide / caprolactone copolymer, PLDL: L-lactide / DL-lactide copolymer, PCL: polycaprolactone, PL: poly(L-lactide). [Table 4]

[0145] Table 5: Antibacterial efficacy of coated implants against Staphylococcus aureus Coatings were fabricated using polymer solutions based on PDLG (DL-lactide / glycolide copolymer) dissolved in TFE (tetrafluoroethylene) and different combinations of hydrophobic (rifampicin, erythromycin, minocycline) dissolved in chloroform and hydrophilic (vancomycin, tobramycin, gentamicin) antibiotics dissolved in dimethylsulfoxide (DMSO). The various combinations showed antibacterial activity with zones of inhibition of microbial growth for at least 6 weeks. [Table 5]

[0146] Suitable drug:polymer ratios have been found to be in the range of 1:1.5 to 1:2.5 (e.g., 1:2). When a higher amount of drug is loaded relative to the polymer, the drug exhibits less sustained release characteristics. When a lower amount of drug is loaded relative to the polymer, the drug exhibits more sustained release characteristics, however, this may result in a lower average daily drug flux (e.g., potentially below the minimum inhibitory concentration).

[0147] 4. Conclusion These experiments identified a formulation for a low viscosity coating solution that can form the basis for a variety of coating techniques (e.g., spray, spin) and has excellent and sustained antimicrobial activity (demonstrated to last at least 6 weeks).

[0148] In particular, coatings obtained from low viscosity coating solutions have 1) be easily adaptable to incorporate different antibiotics of choice (preferably a combination of hydrophobic / non-polar and hydrophilic / polar drugs); 2) It can be applied as a thin coating of a single polymer; 3) high drug loadings can be incorporated; and 4) Has a low enough viscosity to be applied by a variety of coating techniques, including electrospray It has the following characteristics:

[0149] Unexpectedly, it has been discovered that hydrophobic antibiotics (e.g., rifamycin, macrolides, tetracyclines) provided in non-polar or polar aprotic solvents can play an important role in coating solutions due to their viscosity reducing effect. Furthermore, the first antibiotic (i.e., preferably containing a hydrophobic / non-polar antibiotic) solution is preferably mixed first with a non-polar organic solvent to obtain the maximum viscosity reducing effect. It has been shown that the polymer is preferably an aliphatic polyester. Although the polymer is preferably a hydrophobic aliphatic polyester, the inventors believe that hydrophilic aliphatic polyesters may also work in certain embodiments.

[0150] It has been discovered that the coating solution can be easily adapted to coat multiple antibiotics of choice, even when the desired antibiotics have different physicochemical properties (e.g., more or less hydrophilic / polar). The low viscosity may allow coating by spraying, including electrospraying (e.g., performed at dynamic viscosities of 1 mPa·s to 200 mPa·s), or by spin-coating, including electrospinning (e.g., performed at dynamic viscosities of 200 mPa·s to 20 Pa·s).

[0151] Surprisingly, the coating established herein can exhibit interactions between the incorporated drugs (hydrophilic and hydrophobic drugs), allowing for more sustained drug release and higher drug activity. As a result, the coating established herein was effective in eradicating (sterilizing) Staphylococcus aureus (i.e., the most common causative agent of metallic implant infections) over a broad time range.

[0152] Example 2 1. Purpose The objective in this experiment was to compare the two methods with respect to the respective properties of the coating solutions and coatings formed therefrom.

[0153] 2. Method Preparation of Coating Solution - Method A 1. 200 mg / ml PDLG5010 (Corbion) was dissolved in TFE (ABCR) in a light-shielded glass container (20×15 mm) by stirring overnight at 200 RPM using a magnetic stirrer at room temperature. The lid was sealed with parafilm. (Solution A) 175 mg / ml rifampicin (USP, Cepham Life Science) was dissolved in chloroform (Sigma-Aldrich) in a 2.2 mL Eppendorf flask and stirred for 5 minutes using a vortex mixer (Solution B). 3. While stirring solution A with a magnetic stirrer, solution B was added dropwise to solution A using a positive displacement pipette so that the volume ratio was 70:30 (solution A:B). The mixture was stirred for 2 hours in the dark. (Solution C) Vancomycin HCL (USP, Cepham Life Sciences) at 250 mg / ml was dissolved in DMSO (Sigma-Aldrich) in a 4.2 ml Eppendorf, heated to 40° C. using an Eppendorf Thermomixer and stirred at 2200 RPM for 10 minutes (Solution D). 4. While stirring solution C at 1500 RPM using a magnetic stirrer, solution D was added dropwise to solution C using a positive displacement pipette so that the volume ratio was 85:15 (solution C:D). The mixture was stirred at 1500 RPM for 24 hours at room temperature in the dark. (Solution E)

[0154] Preparation of Coating Solution - Method B 1. 200 mg / ml PCL (Corbion) was dissolved in hexafluoroisopropanol (HFIP, Sigma-Aldrich) in a light-shielded glass container (20×15 mm) with magnetic stirring at 200 RPM overnight at room temperature. The lid was sealed with parafilm. 10 mg / ml Rifampicin (USP, Cepham Life Science) was added directly to the PCL / HFIP solution. The solution was stirred at 500 RPM on a shaker protected from light until a clear solution was observed (20 min). (Solution A) Vancomycin HCL (USP, Cepham Life Sciences) at 10 mg / ml was dissolved in MilliQ (ultrapure water) in a 3.2 ml Eppendorf and stirred for 10 seconds using a vortex mixer until the solids were dissolved. The mixture was left for 15 minutes in the dark. (Solution B) 4. While stirring solution A with a magnetic stirrer, solution B was added dropwise to solution A using a pipette so that the volume ratio was 90:10 (solution A:B). The mixture was stirred for 1 hour without blocking light. (Solution C)

[0155] Electrospray The solution was electrosprayed onto the titanium disk surface using the method described in Example 1 (section 2.3.) with a 22 G needle at a voltage of 17 kV, a distance of 8 cm, and a flow rate of 0.5-0.6 mL / h.

[0156] Viscosity measurement The solutions obtained by method A and method B were placed on a shaker and the shaker speed was accelerated from 0 to 500 rpm and then decelerated to a complete stop. Images were taken every second for 45 seconds. The horizontal lines indicate the flow of the solutions during the shaking process. The dynamic viscosity of the antibacterial preparations was measured using a m-VROC viscometer (Rheo Sence).

[0157] Coating Form To characterize the morphology of the coatings, an atomic force microscope (AFM, Amibos tech, US) equipped with a Nanosensors probe (silicon cantilever) was used in tapping mode in the presence of air. For each matrix, 20 × 20 mm scans were taken (n = 5) to obtain accurate test results. The average roughness (Ra) was measured using the Scanning Probe Image Processor (SPIP) software (version 6.7, Image Metrology A / S, Denmark). The porosity and hole size were determined based on the scan of the electron microscope images.

[0158] 3.Results FIG. 9 shows that the coating solution obtained by method A has higher fluidity and lower viscosity compared to the coating solution obtained by method B.

[0159] The coating solutions obtained by method A had dynamic viscosities less than 200 mPa·s, while the coating solutions obtained by method B had greater dynamic viscosities (in the range expressed in Pa·s).

[0160] Using Method A, the drug did not precipitate, indicating excellent drug solubility and miscibility. Method B required more vigorous mixing to prevent drug precipitation, thereby demonstrating suboptimal drug solubility and miscibility.

[0161] In Method A, the particles were deposited by breaking the solution into droplets during the electrospray process, resulting in a homogeneous, low-roughness film, which resulted in a dense, smooth coating (Figure 10). The coating obtained by Method A had no obvious pores.

[0162] In method B, the jet was kept in a continuous form rather than breaking up into droplets to produce fibers with random orientation during the electrospraying process. This resulted in a coating with higher surface roughness and pores (Figure 11). The coatings obtained by method B had a porosity of 70-85% and an average pore diameter of 1-10 μm.

[0163] The pore morphology in the fiber-based coating obtained by method B was consistent with previously reported electrospin coatings in the literature (Biomaterials. 2008 May;29(13):1989-2006; Adv Drug Deliv Rev. 2011 Apr 30;63(4-5):209-20).

[0164] Substituting tobramycin for vancomycin gave similar coatings, demonstrating that different hydrophilic antibiotics can be used. Similar results were obtained when using different hydrophobic aliphatic polyesters; for example, using PLGA instead of PCL in method B gave similar results. Additionally, the fluorocarbon solvent was found to be variable; for example, using hexafluoroisopropanol (HFIP) instead of tetrafluoroethylene (TFE) in method A gave similar results.

[0165] The results of Example 2 are summarized in Table 6. [Table 6]

Claims

1. 1. A method for preparing an antibacterial preparation comprising: a) providing a first solvent having a polymer dissolved therein, said first solvent being a fluorinated solvent and said polymer being an aliphatic polyester; b) providing a second solvent having a first antibiotic dissolved therein, said first antibiotic being hydrophobic; c) mixing the first solvent containing the polymer of step a) with the second solvent containing the first antibiotic of step b), to obtain a mixture having a lower dynamic viscosity than the first solvent containing the polymer of step a); d) providing a third solvent having a second antibiotic dissolved therein, said second antibiotic being hydrophilic; e) mixing the mixture obtained in step c) with a third solvent containing a second antibiotic of step d) to obtain an antibacterial preparation. A method comprising:

2. 2. The method for preparing an antimicrobial preparation according to claim 1, wherein the mixture of step c) and / or the antimicrobial preparation has a dynamic viscosity of 1 mPa.s to 20 Pa.s (Pascal-seconds), preferably 1 mPa.s to 2 Pa.s, more preferably 1 mPa.s to 200 mPa.s.

3. 3. The method for preparing an antibacterial preparation according to claim 1 or 2, wherein the aliphatic polyester is a hydrophobic aliphatic polyester, preferably one or more of PDLG (DL-lactide / glycolide copolymer), PLGA (L-lactide / glycolide copolymer), PLC (L-lactide / caprolactone copolymer), PCL (polycaprolactone), PD [poly(D-lactide)], PL [poly(L-lactide)], or PDL [poly(DL-lactide)], more preferably PDLG.

4. 3. The method for preparing an antibacterial preparation according to claim 1 or 2, wherein the first antibiotic is one or more of a rifamycin, a hydrophobic hydroquinolone, a macrolide, a tetracycline, or a lincosamide, preferably rifampin.

5. 3. The method for preparing an antibacterial preparation according to claim 1 or 2, wherein the second antibiotic is one or more of a glycopeptide, an aminoglycoside, a β-lactam, a carbapenem, a hydrophilic fluoroquinolone, or a streptogramin, preferably vancomycin.

6. 3. The method for preparing an antibacterial preparation according to claim 1 or 2, wherein the fluorine-based solvent is one or more of a fluorocarbon, a fluoroalcohol, or a mixture thereof, preferably tetrafluoroethylene, hexafluoroisopropanol, trifluoroethanol, and trifluoropropanol, more preferably tetrafluoroethylene.

7. In the method: the second solvent is a non-polar organic solvent, a polar aprotic organic solvent, or a mixture thereof, preferably one or more of chloroform, pentane, hexane, benzene, diethyl ether, and 1,40-dioxane, more preferably chloroform; and / or the third solvent is one or more polar aprotic organic solvents, preferably one or more of dimethyl sulfoxide, dichloromethane, tetrahydrofuran, ethyl acetate, acetonitrile, dimethylformamide, dimethyl sulfoxide, acetone, and hexamethylphosphoric triamide, more preferably dimethyl sulfoxide; A method for preparing the antibacterial preparation according to claim 1 or 2.

8. In the method: - in step a), the polymer is present in the first solvent at a concentration of 50 to 500 mg / ml, preferably 100 to 300 mg / ml; - in step b), the first antibiotic is present in the second solvent at a concentration of between 25 and 500 mg / ml, preferably between 50 and 350 mg / ml; - the mixing in step c) is carried out in a ratio of the second solvent containing the first antibiotic to the first solvent containing the polymer in a ratio of 1:1 to 1:2.5, preferably 1:1.5 to 1:2; - in step d), the second antibiotic is present in the third solvent at a concentration of between 25 and 500 mg / ml, preferably between 50 and 300 mg / ml; and / or - in step e), the mixing of the third solvent containing the second antibiotic with the mixture of step c) is carried out in a ratio of 1:2 to 1:7, preferably 1:3 to 1:6, more preferably 1:4 to 1:5; A method for preparing the antibacterial preparation according to claim 1 or 2.

9. 3. Use of the antibacterial preparation according to claim 1 or 2 for preparing an antibacterial coating, preferably by dip coating, spin coating, spraying, electrospinning, electrophoretic deposition, sputter coating, thermal spraying, plasma spraying, sol-gel or layer-by-layer coating, preferably by electrospraying.

10. 10. A method for preparing an antimicrobial coating, said method comprising the steps of applying an antimicrobial preparation obtained according to claim 1 or 2 to a substrate and removing one or more solvents in said antimicrobial preparation, preferably said applying being carried out by dip coating, spin coating, spraying, electrospinning, electrophoretic deposition, sputter coating, thermal spraying, plasma spraying, sol-gel, layer-by-layer coating, more preferably electrospraying.

11. a polymer in a concentration of 10 to 300 mg per ml of antimicrobial preparation, preferably 50 to 150 mg / ml, said polymer being an aliphatic polyester, preferably a hydrophobic aliphatic polyester, more preferably one or more of PDLG (DL-lactide / glycolide copolymer), PLGA (L-lactide / glycolide copolymer), PLC (L-lactide / caprolactone copolymer), PCL (polycaprolactone), PD [poly(D-lactide)], PL [poly(L-lactide)] or PDL [poly(DL-lactide)], most preferably PDLG; - a first antibiotic at a concentration of 10 to 200 mg / ml of the antibacterial preparation, preferably 20 to 100 mg / ml, said first antibiotic being hydrophobic and preferably one or more of a rifamycin, a hydrophobic hydroquinolone, a macrolide, a tetracycline, or a lincosamide, more preferably rifampin; - a second antibiotic at a concentration of 10 to 200 mg / ml of the antibacterial preparation, preferably 20 to 100 mg / ml, said second antibiotic being hydrophilic and preferably one or more of a glycopeptide, an aminoglycoside, a β-lactam, a carbapenem, a hydrophilic fluoroquinolone, or a streptogramin, more preferably vancomycin; a non-polar organic solvent at a concentration of 10 to 50% (v / v), preferably 20 to 40% (v / v), relative to the antimicrobial preparation, said non-polar organic solvent being preferably one or more of chloroform, pentane, hexane, benzene, diethyl ether and 1,40-dioxane, more preferably chloroform; and a polar aprotic organic solvent in a concentration of 1 to 40% (v / v), preferably 10 to 30% (v / v) relative to the antimicrobial preparation, said polar aprotic organic solvent being preferably one or more of dimethyl sulfoxide, dichloromethane, tetrahydrofuran, ethyl acetate, acetonitrile, dimethylformamide, dimethyl sulfoxide, acetone and hexamethylphosphoric triamide, more preferably dimethyl sulfoxide, and having a dynamic viscosity of 1 mPa·s to 200 mPa·s (Pascal-seconds).

12. - a polymer in an amount of 40 to 90% by weight, preferably 50 to 80% by weight, relative to the antimicrobial coating, which polymer is an aliphatic polyester, preferably a hydrophobic aliphatic polyester; - a first antibiotic in an amount of 5 to 40% by weight, preferably 10 to 30% by weight, of the antimicrobial coating, wherein the first antibiotic is hydrophobic; and a second antibiotic in an amount of 5 to 40% by weight, preferably 10 to 30% by weight, relative to the antimicrobial coating, wherein the second antibiotic is hydrophilic; wherein the first antibiotic and the second antibiotic are contained in a matrix acted upon by the polymer, and the antimicrobial coating has a porosity of 10% or less.

13. In the antimicrobial coating: the aliphatic polyester is one or more of PDLG (DL-lactide / glycolide copolymer), PLGA (L-lactide / glycolide copolymer), PLC (L-lactide / caprolactone copolymer), PCL (polycaprolactone), PD (poly(D-lactide)), PL (poly(L-lactide)), or PDL (poly(DL-lactide)), preferably PDLG; - the first antibiotic is one or more of a rifamycin, a hydrophobic hydroquinolone, a macrolide, a tetracycline, or a lincosamide, preferably rifampin; and / or the second antibiotic is one or more of a glycopeptide, an aminoglycoside, a β-lactam, a carbapenem, a hydrophilic fluoroquinolone, or a streptogramin, preferably vancomycin; 13. The antimicrobial coating of claim 12.

14. In antibacterial coatings: - the antibacterial coating is a single layer antibacterial coating, preferably having a thickness of 10 to 1000 μm, preferably 50 to 500 μm, more preferably 100 to 250 μm; - the total polymer content in the antimicrobial coating is 90-100% by weight, preferably 95-100% by weight, more preferably 99-100% by weight, most preferably 100% by weight, of a single polymer; and / or the surface of the antimicrobial coating is hydrophobic, as defined by a static water contact angle of 70° or more, preferably 80° or more, more preferably 90° or more; and / or The antibacterial coating has an average surface roughness of 20 to 1000 nm, preferably 20 to 500 nm, more preferably 20 to 200 nm 14. The antimicrobial coating of claim 12 or 13.

15. 14. An antimicrobial preparation according to claim 11 or an antimicrobial coating according to claim 12 or 13 for the treatment and / or prevention of infections associated with medical devices, preferably infections associated with orthopedic implants.

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