MXPA00005724A - Composition useful for providing one-step surgical preparation and drape - Google Patents

Abstract

This invention relates to an improved polyvinylidene fluoride-based composition useful for forming a flexible, tack-free, nonflammable, substantially fluid resistant barrier film with substantially improved durability and skin-adhesion properties. The composition providing a long-lasting protective barrier film capable of disinfecting the skin surface of normally present microorganisms upon initial application, and the film imparting continuous and prolonged antimicrobial agent. The barrier filmis further capable of remaining substantially adherent to the skin surface after prolonged exposure to biological fluids. A kit and methods of use for the composition are disclosed. The figure illustrates the moisture vapor transmission rate (MTVR) for the present invention. The MTVR of the present invention containing both chlorhexidine acetate (CHA) and silver sulfadiazine (AgSD), chlorhexidine alone, and with no antimicrobial agent present is compared against BLISTERFILM^TM hydrocolloid wound dressing and Saran(R) food wrap. The percent of water loss is plotted versus time in days. The data illustrating the present invention is breathable, thereby providing patient comfort and promotion of wound healing. See Test#3 for details.

Description

USEFUL COMPOSITION TO PROVIDE SURGICAL PREPARATION AND ONE-STEP STERILE COVER The government has certain rights in the present invention in accordance with permit number 1R41 AR / AG44435-01 of the National Institutes of Health.

FIELD OF THE INVENTION The present invention relates to a film-forming composition based on improved polyvinylidene fluoride and a one-step method of use providing a combination of preoperative skin preparation and sterile surgical incision cover. More specifically, the invention relates to an improved polyvinylidene fluoride-based composition useful for removing the microorganisms normally present and imparting prolonged protection against microbial growth of rebound on the surface of the skin. The invention further relates to preventing exposure of the surface of the skin to biological fluids, such as blood, urine and faecal waste.

BACKGROUND OF THE INVENTION Surgical wound infections are an important cause of morbidity, mortality and excesses in hospital costs. Surgical wound infections are the second nosocomial infection most frequently found globally, and among surgical patients, infections at surgical sites are the most common site of nosocomial infection. Three factors contribute to the risk of developing a surgical wound infection: 1) the amount of, and type of, microbial contamination of the wound; 2) the condition of the wound at the end of the operation; and 3) host susceptibility, that is, the intrinsic ability of the patient to treat microbial contamination. In immunocompromised patients, there is a greater tendency for infections caused by bacteria residing in the skin. Infections of surgical sites, which may be benign for most normal patients, can be fatal for the immunocompromised. Accordingly, an object of the present invention is to control bacteria resident in the skin at the site of an invasive surgical procedure. Illustrating the seriousness of the problem, the Centers for Disease Control and Prevention reported that the number of cases of sepsis tripled from 1979 to 1992 due to an increase in invasive procedures in elderly and immunosuppressed patients. In US. Each year approximately 500,000 people acquire sepsis and 175,000 die. A conservative estimate of the average cost of a surgical site infection, as determined on the basis of an average extra length of hospital stay of five days is $ 7,500. In addition to these direct costs, there are significant consequences, such as loss of productivity due to lost work days, emotional trauma caused to patients and health provider as a result of the development of surgical site infections, as a result of the development of surgical site infections, the patient's displeasure with the consequence of the operation, and the fear of bad practice on the part of the health care provider. In order to reduce the risk of wound infection and maximize primary healing, a pre-operative preparation of the skin seeks to create a clean operative field, while minimizing damage to the skin. The preoperative preparation of the skin reduces the risk of postoperative wound infection by removing dirt and transient micro-organisms from the skin, by reducing the resident microbial count to sub-pathogenic quantities in a short period of time, and by inhibiting the rapid growth of microorganism rebound. The objectives of surgical site preparation (scrubbing, antimicrobial skin painting and sterile surgical site coverage) are to remove dirt, oil from the skin and skin microbes, while also providing a barrier against migration of the skin. microbial in the incision. If desired, these goals are achieved with the least amount of skin irritation. It is suggested that the agent used for scrubbing and painting be a broad spectrum antimicrobial that provides residual protection and is non-toxic. An antiseptic solution jdeaj leaves a residue on the surface of the skin that continues to exert antimicrobial activity throughout the surgical period. This residual film should inhibit recolonization of the skin flora from environmental contact, from the centripetal spreading of microbes that originates outside the prepared skin field, and from the resident flora within the prepared field.

Many of the common skin preparation protocols for surgery employ a topical application of an antimicrobial agent. Normally, the topical application of antimicrobial agents is achieved using, for example, lotions, ointments and preoperative preparations of the skin. However, the initial application of the antimicrobial agent frequently does not impart the desired antimicrobial properties and requires continued application. During a surgical procedure, the antimicrobial agent can also be removed by the action of blood, biological fluids and saline washes applied to the site. These two problems can lead to a rebound of the microorganism flora, and result in a post-operative wound infection. Therefore, it is advantageous to have a one-step antimicrobial delivery system, capable of maintaining an aseptic environment in the surgical site before and following the surgical procedure. Other skin preparation protocols for surgery employ a preoperative rubbing procedure, paint and sterile cover. Preoperative rubbing is performed, usually with antibacterial compounds, such as, povidone-iodine, chlorhexidine and hexachlorophene for varied periods (rubs of 2-1 0 minutes). The skin is painted (or atomized) then with the antimicrobial. Povidone-iodine preparations are widely used. 3M Corporation has developed a one-time prepubertal skin solution, DURAPREPMR (US Patent No. 4,584, 1 92), which is painted and dried within 2 minutes. Although skin and skin rubs demonstrate initial microbial inhibition, none have proven effective during longer surgical periods. Sterile covers of film incision with adhesive backing are often applied after the preparation of conventional skin, and surgical incisions are made through the sterile cover. The sterile adhesive covers have proven to be effective in preventing the resident flora from migrating towards the wound, provided they are not detached from the edges of the wound or loosened by trapped fluids or air. However, the intrinsic benefits and antimicrobial effectiveness of the sterile incision cover with traditional adhesive backing are denied by their problems with folds, wrinkles and separation of the wound edge. Eliminating the current practice of using separate antimicrobial preparations and sterile adhesive incision covers would lower the cost of materials, reduce preparation time and decrease the time needed for anesthesia. A combination of antimicrobial preparation and sterile incision cover that could be applied uniformly would benefit the patient by reducing the incidence of the infection, thereby improving the chances of successful surgery and limiting the prolonged postoperative hospital stay due to nosocomial surgical infection. Polyvinylidene fluoride (hereinafter occasionally abbreviated as PVDF) is a mechanically firm thermoplastic that easily and stably pollimates without low molecular weight contaminants or chemical stabilizers PVDF is approved for use by the Food and Drug Administration for contact repeated with food and by the National Sanitation Foundation under Standard 61 for high purity water systems. KYNAR® brand PVDF homopolymers and copolymers (Elf Atochem ATO, Philadelphia, PA) are also in accordance with the US Pharmacopoeia Classification VI. Material safety sheets (MSDS) provided with KYNAR® products indicate that 100% of the respective polymer compound is present without detectable impurities. The present invention addresses the problems in the art with an improved PVDF-based film-forming composition and a one-step method for using a combination of preoperative skin preparation and surgical incision sterile cover. No one before the present inventors performed and demonstrated that PVDF-based coatings could provide an excellent combination of preoperative skin preparation and sterile surgical incision cover as provided above.

DESCRI PCI OF THE PREVIOUS TECHNIQUE .. - ,, Several compositions, are. known in the technique by. form a barrier film when applied to the surface of the skin. It is known that film-forming compositions are useful to provide the skin with protection against irritants, biological fluids and microorganisms, and to form protective bandages for wounds and gloves. A desired film-forming composition should be readily applied to the surface of the skin, substantially fluid-resistant, tack-free, sufficiently permeable to water vapor transmission, adherent, durable and flame-resistant. Another preferred feature is the ability of the barrier film to serve as a vehicle for delivery of an antimicrobial agent and medicament to the surface of the skin. For example, the US patent no. 3,987,000 shows a film-forming polymer composition for providing a protective bandage when applied to a wound site upon atomization from an aerosol container. The composition comprises one or more esters of acrylic or methacrylic acid with one or more primary or secondary aliphatic alcohols, monovalent straight or branched chain, having one to four carbon atoms; one or more monalkyl esters of maleic acid having 1 to 12 carbon atoms in the alkyl moiety; and isobutene. The composition is solubilized in a solvent, such as ethanol, acetone or methylene chloride. The solution is atomized on the surface of the skin using a liquefied propellant gas, such as a halogen hydrocarbon. U.S. Patent No. 4,374, 126 shows a composition and a method for forming a film in one. surface of mammalian skin to provide long-term protection against microorganisms. The composition comprises a carboxylated polyacrylate soluble in alcohol, including an antimicrobial agent, a topical adhesion promoter, and a difunctional amide for crosslinking the polymer upon evaporation of the alcohol solvent. The film is inert to body fluids and provides prolonged antimicrobial properties to the skin by remaining adhered to the surface of the skin in excess of two days. U.S. Patent No. 4,379,863 shows a copolymer-based composition for forming a water-insoluble, breathable barrier film which provides the skin with protection from irritants, such as urine or fecal waste. The copolymer comprises a 50/50 solution of n-butyl methacrylate / iso-butyl, and a plasticizer dissolved in isopropanol. It is also shown that the barrier film is useful to provide protection at an interface between the surface of the skin and the adhesive of a prosthetic device. U.S. Patent No. 4, 584, 192 shows a composition and method for forming a complexed iodine containing film as a broad spectrum antimicrobial to provide aseptic conditions in mammalian skin. The film-forming composition consists of monomers of an acrylic or methacrylic acid ester of an alkyl alcohol, and N-vinyl lactam. The composition is dissolved in an alcohol, such as ethanol and isopropanol. U.S. Patent No. 4, 914, 140 shows a composition for forming one. film.of.protective barrier, in. ia, skin that is. less. irritant because it does not contain surfactants. The film is comprised of an acrylic copolymer of ethyl acrylate and methacrylate acid, and a cellulose derivative dissolved in a solvent mixture of water and alcohol. U.S. Patent No. 5, 547, 662 shows a composition for preparing a skin surface as a surgical site and includes the film-forming material and an antimicrobial agent. The preferred embodiment of the invention consisting of a color change of reactive dye to the removal of the fugitive solvent. Said color change indicates that the site is ready. The invention also shows the use of the invention and a set for its use. U.S. Patent No. 5, 041, 287 shows a composition for forming a flexible, firm film, which provides atomized bandages for mammalian skin surfaces, as well as, atomized gloves and coatings for medical parts and / or electronic devices. The composition comprises polyvinylidene difluoride, an aqueous emulsion of acrylates and methacrylates, an unsaturated carboxylic acid and / or acrylamide, and a plasticizer dissolved in a fugitive solvent. The composition is applied to the skin and forms a film on the evaporation of the solvent. The composition forms a coating suitable for providing a non-grooved polymeric coating, which is easily removable and does not adhere to a wound area. The inventors of the present invention seek to improve upon the composition of the patent 5,041, 287, in order to achieve a composition that forms a film with firmness, adhesion and durability in an environment. humid substantially higher. A film-forming composition useful as an effective pre-operative preparation of one-step skin and sterile surgical incision cover, should encompass a large number of features. It must be substantially adherent to the surface of the skin in the presence of biological fluids, and must be substantially resistant to degradation upon exposure to skin secretions and body oils. The composition should dry quickly on the application to the surface of the skin, providing a firm, flexible, thin and durable film. After training, the film should be well adapted to the movements of the skin and should be free of wrinkles, tears, lifting or bubbles. The film must have a substantial moisture vapor transmission rate that prevents interference with normal skin respiratory processes. Additionally, the film must be highly resistant to burning when exposed to the high-energy lasers frequently used in modern surgical suite series to make an incision. The application of the composition of the film should also be convenient, cost-effective and capable of providing a film with sufficient micro-porosity both to maintain the respiratory processes of the skin and to support the release of an encapsulated antimicrobial agent. The present inventors have actively investigated a composition that meets the above requirements to be used as a combination of preoperative skin preparation and sterile surgical incision cover. Satisfying the __ various requirements before. The inventors describe a composition based on PVDF materially improved comprising an amine-substituted acrylic polymer component. The composition of the present invention provides a film with characteristics that promote skin adhesion and substantially enhanced durability over the prior art. The present invention represents an unforeseen improvement over U.S. Patent no. 5, 041, 287, and these improvements provide a film-forming composition suitable for use as a combination of surgical preparation and sterile cover.

BRIEF DESCRIPTION OF THE INVENTION According to one embodiment of the invention, an improved PVDF-based composition comprising an amine-substituted acrylic polymer component that forms a barrier film with substantial improvements in skin adhesion, firmness is provided. and durability over the prior art. The skin adhesion characteristics and improved durability provide a more durable film to impart the prolonged delivery of an encapsulated antimicrobial agent to the surface of the skin. The durability of the film is further illustrated by its resistance to physical removal. The present invention provides an advantageous step method for eliminating microbial growth from surgical site, and forming a sterile surgical incision cover. The sterile surgical incision cover makes the interface between the skin and the film an aseptic environment. during. and following. the, surgical operation,, En. general, the. method, involves applying the film-forming composition to the surgical incision site, allowing the solvent to evaporate to form a thin, durable, substantially adherent film, free of wrinkles and bubbles. The sterile surgical incision cover is highly resistant to the degradation and removal of biological fluids. The sterile surgical incision cover that is "sufficiently microporous to sustain the release of an encapsulated antimicrobial agent, while not interfering with the respiratory processes necessary for the skin surfaces." In addition, the sterile surgical cover is highly non-flammable. embodiment of the invention is a method of use that provides a protective barrier film on the skin surfaces of incontinent patients.The barrier film provides protection to the skin surface of patients from body excretions, such as urine, fecal matter and transpiration The present invention is sub-substantially resistant to degradation by said bodily excretions.The microporosity of the protective barrier film prevents interference with the respiratory processes of the skin, thus allowing the application of large areas of skin surface. A film-forming composition preferred molecule comprising: (a) about 30 to 60% by weight of solids selected from the group consisting of polyvinylidene fluoride and copolymers thereof; (b) about 10 to 20% by weight solids of a polymer of monomers selected from the group consisting of an alkyl acrylate, an alkyl (meth) acrylate and the copolymers thereof; (c) about 30 to 60% by weight solids of a polymer of monomers selected from the group consisting of dialkylammonoalkylammonylate and the active salts thereof, and a lower alkyl (meth) acrylate; (d) approximately 0.5 to 2.0% water based on the total weight of the composition; (e) an effective amount of an antimicrobial agent; and (f) an aqueous organic solvent for dissolving all components; wherein, said composition when applied to a skin surface from said solvent, it dries in less than one minute forming a substantially durable barrier film, substantially fluid resistant, tack-free, substantially adherent to said skin surface, being said barrier film capable of releasing said antimicrobial agent in an effective amount to substantially impart prolonged antimicrobial properties on said skin surface.

BRIEF DESCRIPTION OF THE DIAMETERS FIG. 1 illustrates the moisture vapor transmission rate (MTVR) for the present invention. The MTVR of the present invention that contains both silver chlorhexidine acetate (CHA) and sulfadiazine (AgSD), chlorhexidine alone and without antimicrobial agent present, is compared against BLISTERFI LMMR hydrocolloid wound dressings and wrapping for, food SARÁN®.- The percentage of loss. of water, you plot against time in days. The data illustrates that the present invention is breathable, thereby providing patient comfort and promotion of wound healing. See Exhibit # 3 for details. FIG. 2 illustrates a drug diffusion assay showing the ability of the coating of the present invention to deliver an antimicrobial agent to provide microbicidal activity against S. epidermidis (diagonal shading) and C. albicans (horizontal shading). The assay was performed with the present invention containing both chlorhexidine acetate (CHA) and silver sulfadiazine (AgSD), chlorhexidine alone, silver sulfadiazine alone and without antimicrobial agent present. The measurement of the microbicidal activity released by the coating of the present invention is plotted as the zone of inhibition in millimeters. The composition of the present invention with the highest microbicidal activity is characterized by a higher numerical value for the zone of inhibition. See Exhibit # 7 for details.

DETAILED DESCRIPTION OF THE INVENTION A problem addressed and solved by the present invention is to reduce the number of infections associated with surgical wounds with an improved PVDF based composition comprising a mixture of PVDF, acrylic polymers and an amine substituted acrylic polymer. . The composition of the present invention results from improvements not foreseen in the prior art (U.S. Patent No. 5, 041, 287). The improvements include substantial increases in the strength of films based on PVDF. to biological fluids, .durability, and properties. , adhesion to the skin. The improvements over the prior art form a film having the desired characteristics necessary to provide a preoperative preparation of the skin and sterile surgical incision cover with sustained release of an effective, one-step antimicrobial agent. The antimicrobial agent removes microbes present on the surface of the skin and continues to inhibit any microbial growth of rebound, fast, over a prolonged period. The improved composition is soluble in a solvent, and when applied to the surgical incision site it dries in less than one minute to form a sterile surgical cover that is substantially non-flammable. In addition, the improved composition does not cause primary irritation or allergic sensitivity when it comes into contact with the skin. The film-forming composition of the invention is also suitable for use as a protective barrier in incontinent patients. The substantial adhesion to the skin and the durability of the invention achieve lasting protection against biological fluids, such as urine, and resistance to separation of the skin by body oils, perspiration and hot water. The coating has additional applicability both as a protective barrier and as a delivery system for preventing infection at the site of an artery-venous dialysis diversion, feeding tube, colostomy tube, urinary catheter or the like. A preferred embodiment of the invention is a barrier film with sufficient moisture vapor permeability supporting the reduction of excessive moisture formation that could macerate the piej and loosen the adhesion of the film. Another feature of the invention is a coating suitable for maintaining the appropriate isothermal environment for a body temperature of the individual. To support both the desired isothermal environment and l. to moisture vapor permeability, it is preferred that the microporosity provide a moisture vapor transmission rate of 0.1 to 1.0 g / cm2 / day. The preferred composition that forms a film with a suitable microporosity includes water. The use of an aqueous acrylic emulsion, such as Rhoplex B-1 5J, is an advantageous method for preparing a composition having the desired microporosity. Rhoplex B-15J is an acrylic polymer available from Rohm & Hass, Philadelphia, PA. It is another feature of the invention that the characteristic microporosity enhances diffusion to the skin surface of the antimicrobial agent or medicament encapsulated within the barrier film. Normal antimicrobial agents that can be delivered to the surface of the skin from the film include antibiotics, iodophors, silver sulfadiazine, chlorhexadine and biologically active salts thereof. An effective antibiotic for preventing antimicrobial growth is nystatin, used in the concentration ranging from about 0.5 to 2.0% of the total weight of said film-forming composition. A more preferable antibiotic is chlorhexidine acetate, or a combination of chlorhexidine acetate and silver sulfadiazine, with each at an effective concentration in the range of about 0.5 to 2.0%. The preferred composition comprising • Clojhexidjna and sulfadiazine of pjata provides upa film that. It has the desired microbicidal activity without altering the film integrity or the desired microporosity. The improved skin adhesion property allows the film to remain attached to the skin for an extended period, allowing for prolonged delivery of a preferred antimicrobial agent.

A suitable drug for delivery to the surface of the skin includes an anti-inflammatory agent, a steroid, an antiviral agent, an antifungal, an anticoagulant, an antiphlogistic, a chemotherapeutic, a haemostatic, a cytostatic and a hormone. A preferred embodiment of the composition further includes a dye soluble in the organic solvent to visually assess the location of the surface of the skin coated with the composition. The dye may act as a visual indicator during the course of a surgical operation, or provide a means to determine when a new coating may be required. Suitable dyes that have virtually no effect on the characteristics of the film include dyes of the Drug and Cosmetic class, such as, Drug and Cosmetic Green No. 6. The preferred range of dye concentration is between 0.01% and 0.1% (p / p) The preferred solvent provides a drying time of less than one minute, and does not compromise the film's firmness, resistance to separation in a humid environment, or the microporous morphology of the film. Examples of solvents that provide the above stated requirements include acetone, ethyl acetate and. mixtures, of the same. The most preferable of the solvents is acetone because of its excellent disinfectant qualities and its volatility, it provides a preferable drying time of less than one minute. Another preferred embodiment of the invention is the advantageous inclusion of a lipid component in the composition. The lipid component provides protection from the irritation of the skin surface caused by the degreasing action of the solvent. Suitable lipids are unsaturated fatty acids, saturated fatty acids and sphingolipids. More preferred lipids include Type I l ceramide, Type IV ceramide, cholesterol and linoleic acid. The preferred range of lipid concentration is between 0.25 and 2.0 parts by weight per 1 0,000 parts by weight of polymer solids. It is a preferred feature of the invention that the sterile surgical incision cover formed by the composition is non-flammable. The most modern surgical rooms use high-energy devices to make an incision in the surgical site. It is highly desirable that the film be substantially resistant to burning and scorching, when exposed to common high-energy surgical devices. The present invention provides a coating that is free from skin irritation upon contact with the surface of the skin. It is a further feature of the invention that the improved composition does not cause skin sensitization or hypersensitivity to delayed contact. Preferably, the composition is composed of. a solids content of about 5 to 10% by weight, to provide suitable films with a thickness of about 0.01 mm to 0.015 mm when applied in simple coatings to the surface of the skin. Films of varying thickness can be obtained using different application methods including painting, spreading, changing, immersion or atomization. Alternatively, the thickness of the coating can be increased using multiple applications. The preferred composition of the invention utilizes polyvinylidene difluoride homopolymer or a copolymer thereof. Suitable copolymers include tetrafluoroethane and hexafluoropropylene. The higher the concentration of PVDF, the firmer the coating will be and the easier it is to separate from the skin. For applications that require flexibility, adhesion to the skin and durability in a moist environment, it is preferable to di the PVDF component by altering the copolymer content or by combining with an acrylic, such as, alkyl (meth) acrylate. For the present invention, other halogen-based polyvinylidene homopolymers, such as polyvinylidene chloride (PVC), can also be used. For purposes of the present invention, an adequate range of PVDF is determined to be about 30 to 60% by weight solids. The composition of the invention comprises about 10 to 20% by weight solids of a polymer of acrylic monomers selected from the group comprising alkyl (meth) acrylates. It is known that the normal alkyl (meth) acrylics suitable for use in the invention comprise methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, propyl methacrylate, ethoxyethyl acrylate, methoxyethyl acrylate, methoxyethyl methacrylate, ethoxyethyl methacrylate and the like. To prepare the composition of the invention, it is beneficial to prepare an aqueous emulsion of the acrylic compounds before combining with the polyvinylidene fluoride. Preferred acrylic polymer dispersants include the following: 1. methyl methacrylate, butyl acrylate and acrylic acid 2. propyl methacrylate, butyl acrylate and acrylic acid 3. methacrylate demethoxyethyl, butyl acrylate and acrylic acid 4. methyl methacrylate , 2-ethylhexyl acrylate and methacrylic acid. The film-forming composition of the present invention represents an improvement not foreseen in the prior art in which the addition of an amine-substituted acrylic polymer of monomers selected from a group consisting of dialkylaminoalkyl (meth) acrylate, and a lower alkyl (meth) acrylate would provide a composition that forms a protective coating with substantial increases in skin adhesion and durability in a humid environment. A preferred coating for forming a sterile surgical cover comprises about 30 to 60% by weight of the acrylic polymer substituted with amine. The inclusion of an amine-substituted acrylic polymer in the prior art composition provides a film capable of remaining substantially intact and 100% bound to a glass slide for 14 to 1 9 days of submersion at 37 ° C of water (Formulation in EXAMPLE 1 9). This represents a substantial increase in skin adhesion and durability over the prior art (U.S. Patent No. 5,041,287), which appears to be able to remain intact in 1 00% attached to a glass slide for 24 to 48 hours of submersion at 37 ° C. When tested on human skin, the film of the present invention remained intact and 100% bound for at least 34 hours, while the film prepared from the composition of the prior art began to show separation at 20 hours. The preferred embodiment of adhesion to the skin allows for greater retention of the film during a surgical procedure, providing the means for delivery of an encapsulated antimicrobial agent and protection of the surgical site from contamination. Suitable dialkylaminoalkyl (meth) acrylates, which can be used to prepare the amine-substituted acrylic polymer include NN-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, t- (meth) acrylate butylaminoethyl and active salts thereof. It has been found that about 20 to 30% by weight of the amine-substituted acrylic polymer of the total solids content is suitable for the coatings of the present invention. Suitable lower alkyl (meth) acrylates, which can be used to prepare the amine substituted acrylic polymer, comprise those having 1 to 8 carbon atoms in the alkyl group, such as methyl acrylate., acrylate and ethyl, isopropyl acrylate, methacrylate, methylo, propyl methacrylate, ethoxyethyl methacrylate, and the like. A preferred composition for forming a sterile surgical cover has a solids content of about 5 to 10%, and comprises about 30 to 60% by weight of polyvinylidene difluoride, 10 to 20% by weight of a mixture of methyl acrylate and methyl methacrylate, 30 to 60% by weight of a polymer comprising N, N-dimethylaminoethyl methacrylate and methyl methacrylate. It is a feature of the invention that the improved composition is used as a one-step method for a combination of surgical site preparation and sterile cover. The present invention can be applied either by painting, spreading or atomization. After the composition is applied to the selected surgical site, the solvent is allowed to evaporate. The time allowed for evaporation is fast, occurring in less than a minute. The presence of the dye in the composition provides the individual application of the film with the means to visualize whether the surgical site is adequately covered. Once the desired surgical site is covered, the film provides a sterile cover of substantially durable quriuric incision that promotes aseptic conditions on the surface of the skin, through the combined action of the solvent and sustained release of an encapsulated antimicrobial agent. The surgical incision can then be made through the sterile surgical cover without burning or scorching the film. In practice, another feature of the invention is a set for applying the composition to the surface of the skin including a sealed container having an application means. Preferably, the application means is coupled to the container and comprises a pump atomizer, sponge, cloth, gauze, cotton, wool, brush or roller ball applicator. A preferred feature of the assembly is that it can be contained within a sealed package that is capable of being sterilized, thus providing an adequate and convenient means for applying the composition to the sterile environment of a surgical room. The following example compositions are provided to illustrate the invention, but should not be considered as limiting the invention. By way of example, a list of useful components and their sources is given in Table I.

TABLE I. Commercially available sources of components EXAMPLE 1 A suitable composition was prepared to form a sterile surgical incision cover as follows, using commercially available compositions. Component Weight Kynar 7201 5 g Rhoplex BJ-1 5 2.5 g Eudragit E 1 00 2.5 g Acetone 90 g Preparation of the composition is carried out at room temperature with an anchor stirrer. The listed components are placed sequentially in a laboratory beaker, and the composition was thoroughly mixed by stirring overnight to prepare 10% by weight of a polymer solids composition. The prepared composition easily forms a durable, substantially adherent film upon application to the surface of the skin and evaporation of the solvent.

EXAMPLE 2 Following the procedure of EXAMPLE 1, a film-forming composition with the desired microbicidal activity comprising both 0.5% chlorhexidine acetate and 0.5% silver sulfadiazine was prepared by weight. 0.5 grams of each antimicrobial agent provides a coating based on PVDF, suitable for eliminating microbes normally present from the surgical incision site, and provides for rapid rebound microbial growth. This composition provides a combination of a preferred step of surgical site preparation and sterile cover.

EXAMPLE 3 Following the procedure of EXAMPLE 1, a composition containing cholesterol, palmitic acid, ceramide III and ceramide IV was prepared. The resulting film provides a sterile surgical incision cover that stops the degreasing action of the solvent in the composition. The amounts of the lipid in this example are given in TABLE I I.

TABLE I I The invention is further illustrated by the following test objectives.

TEST # 1 - FLAME PROPAGATION TEST The tendency of the dry film of the invention to propagate a flame was determined using a modification of the standard test of Underwpters Laboratory UL94 ("Plastics material for parts and devices and appliances"). Plastic materials for parts in devices and apparatuses) (1991) Using the composition described in Example 1, a glass microscope slide of 75x25x1 mm was coated by rubbing with a sponge flooded with the composition either immediately or after drying In the complete, the coated slide is passed through a bunsen burner to ignite the composition.The coated slide is inserted into the flame by varying angles to observe the degree to which a flame consumes the composition. 1 80 °, at 0o, the specimen points upwards ("North") and a flame is removed from the film, so at 0o the coating is subjected to the condition smoother in the test. Highly flammable materials will withstand a flame at 0o. Lightly flammable materials will withstand a flame at 180 °, but flammable materials will not. At intermediate angles progressively decreasing (135 °, 90 °, 45 °) less the specimen comes into contact with the flame; so that the severity of the test is reduced as the angle is decreased. Therefore, the smaller the angle that supports the propagation of a flame, the greater the danger. Another aspect of fire hazard is the time during which initially flammable materials, such as solvent based coatings, remain flammable after they have been applied. This was evaluated by allowing the coatings to dry for varying periods, at room temperature, and then subject them to the flame propagation test at 1 80 °. This test provides a measurement of the time in which the coating remains in danger of fire. It is preferred that the coating be flammable for a short period after application. The results of the two flammability tests are described in Table III and IV.

TABLE l l l. Flammability of PVDF-based skin preparation coating materials Composition Coating Flint anguine Specimen Wet / dry no. (°) consumed (%) tests Example 1 Wet 180 100 2 90 1 00 2 45 1 00 2 0 100 2 Example 1 Dry 1 80 0 3 90 0 2 45 0 2 0 0 2 The results of the flame propagation test demonstrate that the PVDF-based coating will propagate a flame before drying, but quickly become flammable. As shown in Table IV, the composition provides a sterile flammable surgical incision cover at the test angle of 1 80 ° after a drying time of less than 1.5 sec.

TABLE IV. Drying time required for surgical coating to become flammable at a test angle of 1 80 ° Composition Drying time (s) No. of tests Example 1 8-1 3 TEST # 2 - I NFLAMABI LI DAD OF FILM WITH HIGH ENERGY ROTARY TOOLS The films formed from the composition of this invention can be subjected to modern high-energy surgical instruments and therefore, must be resistant to flame. To determine the flame resistance of the film, the composition described in EXAMPLE 2 was applied to the skin of an orange and the outer skin portion of a ham hock, and allowed to dry for one minute. Following this drying time, the commonly used surgical lasers (TABLE V) were used to test their burning effect on the film coating. No laser resulted in burning or scorching of the film coating. The dry films of the invention, therefore, do not pose a fire hazard when used in conjunction with the high energy devices present in modern surgical rooms.

TABLE V. Flammability of the PVDF-based coating used with high-energy surgical instruments Orange Ham hock Instrument and adjustment Flama Flama YES NO YES NO 1.06μm neodymium laser, Coherent VersaPlus Select Nd-Yag: Fit: High; Time: 120 s; Power: 60 watts X X 2.1μm holmium laser, Coherent VersaPlus Select Nd-Yag: Fit: High; energy: 28 Joules; Speed: 20 X X pulses / second ConMed Excalibur Plus Bovie: Standard setting; coagulation 50 X X Standard adjustment: 25 X X cut High setting: 120 X X coagulation High adjustment: 180 X X cut Storz Optical Fiber: 100% illumination (max); 1 minute X X TEST # 3 - MICROPOROSI DAD AND HUMIDITY VAPOR TRANSMISSION MICROPOROSITY Microporosity is an essential feature of a sterile surgical incision cover. The moisture vapor transmission rate (hereinafter referred to as MTVR) is the measure the capacity of the film to allow air and air vapor to pass through it while preventing the passage of liquid water. MTVR is directly related to the microporous morphology of a film, and is defined by the presence of pores that extend throughout the film. MTVR provides a physical barrier to moisture, while allowing moisture vapor to infiltrate. The micro-quality, and thus the MTVR of the invention can be adjusted over a wide range of composition variations. When examined under an electron microscope at 1 0.000X, it is found that a coating prepared from the composition in EXAMPLE 1 contains pores of approximately 0.1 to 2.0 μm in diameter. For the present test, various coating compositions were tested to determine the effect of an amine-substituted acrylic monomer that would have on the formation of the required microporous morphology for a suitable sterile surgical cover. It was found that the presence of acrylic monomer substituted with amna in combination with an aqueous acrylic emulsion (Rhoplex-R B-1 5J emulsion, Rohm and Haas Company, Philadelphia, PA), formed one. movie on the appropriate MTVR. To test the MTVR of the present invention, films based on PVDF having 0.5% w / w of chlorhexidine acetate, PVDF-based films containing a combination of 0.5% w / w of chlorhexid acetate ina and 0.5% p were tested. / p of silver sulfadiazine, PVDF-based films without antimicrobial, BLISTERFILMMR hemrocolloid wound dressing, and SARAN® food wrap, to determine which had the highest MTVR (see FIG 1). BLISTERFI LMMR is a commercial hydrocolloid wound dressing that is described as having a relatively tight MVTR, which is suitable for promoting wound healing. Films based on PVDF were prepared following EXAMPLE 1 and EXAMPLE 2, respectively. Three replicates of each test sample were spread over the mouths of 28.5 mm diameter tubes filled with 30 grams of distilled water. The tubes were stapled in an inverted position, and placed in a controlled environment room at 37 ° C and 24% relative humidity for seven days. The amount of water loss due to evaporation was monitored for several days. The improved composition (EXEM PLO 1 AND 2) demonstrated a relatively high moisture vapor transmission rate. As shown in FIG. 1, the percentage of water lost over time remained linear up to 1 00% of water loss. Additionally, FIG. 1 illustrates that the MTVR of the present invention is substantially greater than both BLISTERFI LMMR hydrocolloid wound dressings such as the SARAN® food wrap. This result illustrates that a preferred feature of the invention is a substantially porous and breathable film. This preferred feature maintains the appropriate isothermal environment for the patient's body temperature, ensures adequate adhesion by preventing the formation of moisture, and provides a route for the release of encapsulated antimicrobial agents within the coating. TEST # 4 - EVALUATION OF THE INVENTION AS AN I RRIANT PRI MARIO To determine if the preferred composition of the invention causes skin irritation, the following test was followed. One day before the application of the coating, the hair on the back of six New Zealand White rabbits was removed with a shearer. The surface of the skin on one side of the shaved area was left untouched, while the other side was irritated by scratching with a sharp object. A 0.5 ml portion of the PVDF-based coating of EXEM PLO 1 was applied to both the untouched and irritated skin, and covered with 645.2 mm2 pieces of gauze sponges. The application sites were further protected by wrapping the trunks of the animals with gauze and securing them with elastic bandages. The untreated and irritated test sites were given a pre-assigned rating for both erythema and edema formation 24 hours and 72 hours after the application of the coating (TABLE VI). The sum of the eight erythema and edema values were divided by four to give a primary irritation score. The average primary irritation index was determined by dividing the primary irritation rating by six, the number of test animals. The coating reaction was then assigned as a descriptive classification, from this index, providing an average primary dermal irritation score (TABLE VI).

TABLE VI: Evaluation of skin reactions Formation of erythema and scab Value No erythema 0 Very light erythema (poorly noticeable) 1 Well-defined erythema 2 Moderate to severe erythema 3 Severe erythema to light scab formation 4 Edema formation Value No edema 0 Very light edema (poorly perceptible) 1 Light edema (edges of well-defined area) 2 Moderate edema (raised approximately 1 mm) 3 Severe edema (raised more than 1 mm) 4 TABLE VI l: average primary irritation index / descriptive classification Range of values Classification descriptive 0 Non-irritant 0.1 -1 .9 Mildly irritating • • 2.0-5.9 Moderately irritating 6.0-8.0 Severely irritating Seven of the 48 possible test sites recorded one having only a scarcely visible erythema formation present (see Table VI). In this way, the composition of the invention had an average primary dermal irritation score of 0.3. As shown in Table VI, mild irritants have values ranging from 0.1 to 1.9, indicating that the composition of the invention falls to the lower end of the "mildly irritating" category. A slight irritation is expected with the introduction of a solvent to an area subject to prior irritation. The results of this test show that the preferred composition of the invention does not cause substantial skin irritation, but shows only mild signs of irritation when applied to previously irritated skin.

TEST # 5 - LIFE DURABLE LIFE A preferable feature of a PVDF-based composition useful for a one-step skin preparation and sterile surgical cover is sufficient durability and adhesion under end-use conditions. To determine whether the invention provided the desired durability and adhesion, the coating was applied to the skin of human volunteers and subjected to end-use conditions. The volunteers applied the composition prepared in EXAMPLE I to the antecubital cavity of both arms. The coatings were observed for eight hours or more before the volunteer took a shower or a bath in a tub. Each volunteer subjectively evaluated the results of the experiment according to a rating scale. The classification scale was the percentage of coating that remained intact in each examination. Coating remained 90% to 100% intact without separation or disbonding after bathing. After continuing to use the coating for a total of 24 hours, no more than 10% of the film had been raised along the edges of the coated area. It was found that the film separated radically and flaked off after 48 hours of use. The results of the live durability test show that the invention provides a substantially durable film coating, resistant to body oils, perspiration and hot water.

PREUBA # 6 - RESISTANCE OF BIOLOGICAL FLOW COATING FOR USE OF THE COMPOSITION As a sterile surgical cover it is highly desirable that the film remain substantially adherent and maintain adequate moisture vapor transmission in the presence of fluids. biological The PVDF-based coating prepared in EXAMPLE 1 was evaluated for its resistance to separation in the presence of biological fluids by submersion of a microscope slide coated with blood film, distilled water, saline, urine, and heparin blood. of sodium for three days at 37 ° C. The integrity of. the coatings were classified daily according to a scale of five points, varying from zero to four, where zero represented 1 00% separation, and four represented no separation (0%) of the film from the slide. Following this protocol, the surgical sterile cover coating remained fully adhered to the slide after three days of continuous immersion in water, saline solution and blood. In urine, there was a slight detachment at the edges after two days (classification of 3), which progressed to a classification of 2 (25-50% separation) after three days of continuous immersion. To evaluate the MTVR of the films after exposure to biological fluids, the test procedure described in TEST # 3 was followed. The compared films were initially subjected to a 7-hour exposure to blood, urine and water in a closed environment at 37 ° C, followed by a saline rinse. The films were then stretched over the mouths of 28.5 mm diameter tubes filled with saline to test the MTVR. After 7 hours of exposure, there was a small but not significant decrease in the moisture vapor transmission rate, and no visible indication of leakage through the film. The results of the biological fluid resistance test demonstrate the integrity and continuous protective function of the composition when used as a sterile surgical cover or protective barrier for an incontinent individual.

TEST # 7 - MEDICATION TISSUE FUSION TEST The ability of a film coating to release antimicrobial agents to the surface of the skin is a preferred embodiment of the present invention. To evaluate the ability of the present invention to deliver encapsulated antimicrobial agents to the surface of the skin, a zone of inhibition test was performed. For this test, the formulation of PLO 1 EXEM was analyzed, containing either 0.5% chlorhexidine acetate, 0.5% chlorhexidine acetate and 0.5% silver sulfadiazine, or 2.0% silver sulfadiazine. Two coatings of the improved formulation were applied on one side of a 9.8 mm polyethylene disc to an average thickness of 0.014 mm. The five discs were prepared for each test solution. Five discs coated with the improved composition without an encapsulated antimicrobial agent were included as controls. The coatings were allowed to dry completely and then inverted onto agar plates of buffered yeast morphology which had been inoculated with C. albicans or S. epidermidis with a swab. The plates were incubated at 37 ° C for 24 hours. Determining the distance in millimeters from the periphery of the film-coated disc to active microbial growth sites provides a measure of the zone of inhibition. The zone of inhibition is produced by diffusion outside the film of an antimicrobial encapsulated to the agar substrate, thereby eliminating any microbial growth surrounding the film-coated disc. In this way, the ability of a film to release increasing amounts of antimicrobial agent is characterized by a zone of expanded inhibition. As shown in FIG. 2, the improved composition containing the combination of 0.5% chlorhexidine acetate and 0.5% silver sulfadiazine, provided the greatest zone of inhibition with an area of S. epidermidis inhibition of 16 mm. The results demonstrate that the improved PVDF-based coating can effectively release chlorhexidine acetate, can sulfadiazine and a combination of chlorhexidine acetate and silver sulfadiazine. The control discs exhibited no inhibition therefore no antimicrobial activity.

TEST # 8 - ACTIVI DAD MICROBITION OF DRY COATINGS An effective sterile surgical cover provides microbicidal activity against a variety of microorganisms. To evaluate the microbicidal activity of the composition including an antimicrobial agent, a modified in vitro test found in the technical literature, supplied by 3M Corporation for DURAPREPMR, was used. In the 3M study design, the coatings were applied to filters pre-seeded with microorganisms followed by 5 minute homogenization of the filters. The homogenized filters were then platinized into nutrient substrates. The 3M technical literature reports a 1% death within 1 minute of application using this method. However, these results are to be expected considering that the 3M solution contains 74% isopropyl alcohol (w / w). In this way, the inventors were interested in that the high concentration of acetone of the improved composition, with its inherent microbicidal properties, would eliminate all viable microorganisms without considering the encapsulated antimicrobial agent. Therefore, the modified version of the in vitro test involves coating the filter with the test composition, allowing the acetone to evaporate completely, and then sowing the filter with micro-organisms. The modified version provides a severe test of the microbicidal properties of one of the desired compositions including an antimicrobial agent. The test was performed using the formulation prepared in EXAMPLE 1, containing by weight, either 0.5% chlorhexidine acetate or 0.5% chlorhexidine acetate and 0.5% silver sulfadiazine. The test for Escherichia coli was performed as follows: 1. E. coli was grown in Trypticase Soy Agar (TSA) at 37 ° C. 2. The next morning, colonies of E. coli were swabbed from the plate and diluted to an O. D. 530 of 0.05 with phosphate buffered saline (PBS). 3. Hydrophilic polypropylene membrane filters from Gelman (47 mm, 0.045 μm) were placed on the support and uniformly painted with the combination of PVDF and antimicrobial using a brush. The polymer-coated membranes were allowed to air dry for 2 minutes at room temperature. 4. The bacterial suspension (0.1 ml) described above was placed on the coated membrane and spread aseptically and uniformly through the film-coated membrane. 5. At 0 minutes, 2 minutes, 10 minutes and 30 minutes, the filters were aseptically placed in 10 ml Letheen + 0.1% sodium thiosulfate to inactivate the antimicrobial agent, and vortexed 30 seconds to dislodge the bacteria. 6. The suspension of dislodged bacteria were serially diluted in diluted water diluted with phosphate and plated on TSA plates for the determination of the number of viable bacteria per ml. 7. The colonies were counted and recorded as the number of viable bacteria (per ml) dislodged from the surface of the membranes coated with PVDF. The log reduction in viability was determined by comparing the number of viable bacteria discharged from the surface of the coating with and without an antimicrobial. The results of the purée show that the microbicidal activity of the PVDF-based composition containing a combination of chlorhexidine acetate and silver sulfadiazine has substantial in vitro microbicin activity. The composition of the test provides substantial reductions in the colony forming units in 1, 2, 1 0 and 30 minute incubations. The test was performed with similar results for Staphylococcus epidermidis, Pseudomonas aeruginosa, Staphylococcus aureus, Proteus vulgaris, Candida albicans, Serratia marcesens and Trichophyton mentagrophytes. The test results demonstrate that encapsulated antimicrobial agents within the improved PVDF-based coating of the present invention provide substantial in vitro microbicidal activity against a variety of organisms.

Claims (30)

1. REIVI NDICATIONS 1 . A film-forming composition for providing a protective coating on a skin surface, comprising: (a) about 30 to 60% by weight solids selected from the group consisting of polyvinylidene difluoride and copolymers thereof; (b) about 10 to 20% by weight solids of a polymer of monomers selected from the group consisting of a lower alkyl acrylate, a lower alkyl (meth) acrylate, a lower hydroxy alkyl acrylate, an alpha unsaturated carboxylic acid beta having a number of about 20 to 150, and the copolymers thereof; (c) about 30 to 60% by weight solids of a polymer of monomers selected from the group consisting of dialkylaminoalkyl (meth) acrylate and lower alkyl (meth) acrylate; (d) about 0.5 to 2.0% water based on the total weight of the composition; (e) an effective amount of an antimicrobial agent; and (f) an aqueous organic solvent for dissolving all components.
2. 2. The composition of claim 1, further comprising a medicament.
3. 3. The composition of claim 2, wherein said medicament is selected from the group consisting of an anti-inflammatory agent, a spheroid, an antiviral agent, an antifungal, an anticoagulant, an antiphlogistic, a chemotherapeutic, a hemostatic, a cytostatic and a hormone.
4. 4. The composition of claim 3, wherein said cytostatic is a silver compound.
5. The composition of claim 1, wherein said antimicrobial agent is substantially releasable in an amount sufficient to substantially impart prolonged antimicrobial properties on said surface of the skin, said antimicrobial agent being selected from the group consisting of antibiotics, iodophors, sulfadiazine silver, chlorhexadine and biologically active salts thereof.
6. 6. The composition of the re-excitation 5, wherein said antibiotic is nystatin present in an amount ranging from about 0.5 to 2.0% of the total weight of said film-forming composition.
7. The composition of claim 1, wherein said solvent is selected from the group consisting of acetone, ethyl acetate and mixtures thereof.
8. The composition of claim 1, wherein said solids comprise between about 5 to 10% of the total weight of said film-forming composition.
9. 9. The composition of claim 1, further comprising a colorant soluble in said organic solvent.
10. The composition of claim 9, wherein said dye is Drug and Cosmetic Green No. 6.
11. 1 1. The composition of claim 1, further comprising a lipid component.
12. 12. The composition of claim 1, wherein said lipid component is selected from the group consisting of an unsaturated fatty acid, a saturated fatty acid and an idyllic sphingol.
13. The composition of claim 1, wherein said lipid component is selected from the group consisting of Type I l ceramide, Type IV ceramide, cholesterol and linoleic acid.
14. The composition of claim 1, wherein said lipid component is present in an amount of about 0.25 to 2.0 parts by weight per 10,000 parts by weight of polymer solids in said composition. 5.
15. The composition of claim 1, wherein said dialkylaminoalkyl methacrylate is about 6 to 16% of the total weight of all solids in the composition.
16. The composition of claim 1, wherein said dialkylaminoalkyl (meth) acrylate is selected from the group consisting of N-dimethylaminoetiio (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, (meth) t-butylaminoethyl acrylate and active salts thereof.
17. 17. The composition of claim 1, wherein said protective coating has a moisture vapor transmission rate of about 0.1 to 1.0 g / cm2 / day, said moisture vapor transmission rate being sufficient to substantially maintain the Isothermal environment of said skin surface. 1 8.
18. A method for imitating and inhibiting microbial growth at a skin surface site, comprising the steps of: (a) applying said film-forming composition to said skin surface site in claim 1; (b) allowing evaporation of the solvent of said film-forming composition to form a protective film coating; (c) allowing said protective coating to remain at said skin surface site to release antimicrobial agents in an amount sufficient to substantially eliminate microbes present and inhibit rebound microbial growth at said skin surface site.
19. The method claimed in claim 18, wherein said site is a surgical procedure site and said film forming composition forms a sterile surgical incision cover, substantially fluid resistant, substantially durable and substantially adherent, said sterile cover being capable of surgical incision to release a medicament and an antimicrobial agent in an amount capable of imparting substantially prolonged antimicrobial properties at said surgical procedure site.
20. The method claimed in claim 18, wherein said film-forming composition is applied to the surface of the skin of an incontinent person, forming a barrier film substantially fluid-resistant capable of imparting prolonged antimicrobial properties on the surface of the skin of said incontinent person. twenty-one .
21. The method claimed in claim 1 8, wherein said application is by painting, spreading, changing, dipping or atomizing.
22. 22. The method claimed in claim 18, wherein said barrier film is approximately 0.01 0 mm to 0.01 5 mm thick, when dried, on the surface of the skin.
23. 23. A set for applying the film-forming composition to a skin surface site, said assembly comprising: (a) a sealed container for containing said film-forming composition in claim 1; (b) coating means for applying said film-forming composition to said skin surface site; and (c) a sealed package for holding said sealed container and said means for applying said film-forming composition.
24. 24. The assembly claimed in claim 23, wherein said assembly is sterilizable.
25. 25. The assembly claimed in claim 23, wherein said coating means is selected from the group consisting of a spray pump, sponge, cloth, gauze, cotton, wool, brush or roller-ball applicator.
26. 26. A film-forming composition for providing a protective coating on a surface of the skin, comprising: (a) about 30 to 60% by weight solids selected from the group consisting of polyvinylidene difluoride and copolymers thereof; (b) about 10 to 20% by weight solids of a polymer of monomers selected from the group consisting of a lower alkyl acrylate, a lower alkyl (meth) acrylate, a lower alkylacrylate of hydroxy, an unsaturated carboxylic acid alpha beta having a number of about 20 to 150, and the copolymers thereof; (c) about 30 to 60% by weight solids of a polymer of monomers selected from the group consisting of dialkylaminoalkyl (meth) acrylate and lower alkyl (meth) acrylate; (d) about 0.5 to 2.0% water based on the total weight of the composition; (e) a lipid component that is present in an amount of about 0.25 to 2.0 parts by weight per 10,000 parts by weight of polymer solids; (f) an effective amount of an antimicrobial agent; and (g) an aqueous organic solvent to dissolve all the components.
27. The composition of claim 1, wherein said composition when applied to a skin surface of said solvent is dried in less than one minute, forming a substantially durable barrier film, substantially fluid resistant, tack-free, substantially adhering to said skin surface, said barrier film being capable of releasing said antimicrobial agent in an effective amount to substantially impart prolonged antimicrobial properties on said surface of the skin, said barrier film being substantially porous, said pores varying in the dimension of approximately 0.1 microns at 2.0 microns in diameter.
28. The composition of claim 26, wherein said composition, when applied to the skin surface of said solvent, dries in less than one minute, forming a substantially durable barrier film, substantially fluid resistant, free of stickiness, substantially adhering to said surface, said barrier film being capable of releasing said antimicrobial agent in an amount effective to substantially impart prolonged antimicrobial properties on said skin surface, said barrier film being substantially porous, said pores varying in dimension from about 0.1 micron to 2.0 micron in diameter.
29. 29. A film-forming composition for providing a protective coating on a skin surface, comprising: (a) about 30 to 60% by weight solids selected from the group consisting of polyvinylidene difluoride and copolymers thereof; (b) about 10 to 20% by weight solids of a polymer of monomers selected from the group consisting of a lower alkyl acrylate, a lower alkyl (meth) acrylate, a lower hydroxy alkyl acrylate, an alpha beta unsaturated carboxylic acid having a number of about 20 to 150, and the copolymers thereof; (c) about 30 to 60% by weight solids of a polymer of monomers selected from the group consisting of a dialkyl aminoalkyl (meth) acrylate and lower alkyl (meth) acrylate; (d) about 0.5 to 2.0% water based on the total weight of the composition; (e) an aqueous organic solvent to dissolve all the components;wherein said composition when applied to a surface of the skin from said solvent, dries in less than one minute, forming a substantially durable film, substantially fluid resistant, tack-free, substantially adherent to said skin surface. The composition of claim 1, wherein said antimicrobial agent further comprises chlorhexidine acetate and silver sulfadiazine in an amount ranging from about 0.5 to 2.0% of the total weight of said film-forming composition. (54) Title: COMPOSITION USEFUL TO PROVIDE SURGICAL PREPARATION AND STERILE COVER OF A STEP (57) Summary: This invention relates to a composition based on improved polyvinylidene fluoride, useful for forming a flexible barrier film, tack-free, non-flammable, substantially fluid resistant, with substantially improved skin adhesion properties and durability. The composition provides a durable protective barrier film capable of disinfecting the surface of the skin of microorganisms normally present on the initial application, and the film imparts an antimicrobial agent in a continuous and prolonged manner. The barrier film is also capable of remaining substantially adherent to the surface of the skin after prolonged exposure to biological fluids. A set and methods of use for the composition are described. The figure illustrates the moisture vapor transmission rate (MTVR) for the present invention. The MTVR of the present invention containing both chlorhexidine acetate (CHA) and silver sulfadiazine (AgSD), chlorhexidine alone, and without antimicrobial agent present, is compared against the wound dressing of BLISTERFI LM R hydrocolloid and Sarán® food wrap. The percentage of water loss is plotted against time in days. The data illustrate that the present invention is breathable, thereby providing comfort to the patient and promotion of wound healing. See Test # 3 for details.