AU2024207799A1 - Containers and methods for nitric oxide sterilization - Google Patents

Abstract

Devices and methods of sterilizing an object are presented in which the object is sealed in a container that includes a nitric oxide permeable microbial barrier that allows for permeation of nitric oxide into the container to reach sterilizing conditions within the container. In typical embodiments, the sealed container is placed in a sealable second container into which nitric oxide is fed or in which nitric oxide is generated. From the sealed second container, nitric oxide enters the container with the object through the nitric oxide permeable microbial barrier to provide a sterilizing nitric oxide concentration. Advantageously, contemplated devices and methods allow for rapid sterilization at low temperatures and do not present a hazard for the operator or environment.

Description

CONTAINERS AND METHODS FOR NITRIC OXIDE STERILIZATION

Cross Reference to Related Applications

[0001] This application claims priority to copending US provisional patent application No. 63/438,073, which was filed January 10, 2023, and which is incorporated by reference herein.

Field of the Invention

[0002] The field of the invention is devices and methods for sterilizing objects in an enclosed environment using nitric oxide as sterilant, and especially as it relates to containers having a nitric oxide permeable microbial barrier that allows for permeation of nitric oxide into the container to reach sterilizing conditions within the container.

Background of the Invention

[0003] The background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.

[0004] All publications and patent applications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.

[0005] Sterilization of medical devices and equipment is paramount for their safe use and the most common methods of sterilization include steam autoclaving and irradiation. However, not all medical devices, equipment, and biologies can withstand such harsh conditions, and other sterilization methods must be used. Among other options, sterilization can be performed using certain gases. For example, ethylene oxide is the most commonly used sterilizing gas for items such as surgical kits, catheters, cardiac implants, stents, IV sets, etc. Unfortunately, ethylene oxide possesses several physical and health hazards that merit special attention. According to the Occupational Safety & Health Administration of the U.S. Department of Labor, acute exposures to ethylene oxide gas may result in respiratory irritation and lung injury, headache, nausea, vomiting, diarrhea, shortness of breath, and cyanosis. Chronic exposure has been associated with the occurrence of cancer, reproductive effects, mutagenic changes, neurotoxicity, and sensitization. Indeed, the Environmental Protection Agency has classified ethylene oxide as a carcinogen.

[0006] To avoid some of the difficulties with ethylene oxide, other sterilizing gases can be used. For example, formaldehyde can be generated from formalin and has been employed as a sterilizing gas at relatively high concentrations (e.g., 8-16 mg/1). While significantly less flammable than ethylene oxide, formaldehyde gas is generated/used at an operating temperature of about 70-75 °C, which precludes its use with thermally sensitive material or equipment. Alternatively, hydrogen peroxide vapor can be used as a sterilizing gas. Hydrogen peroxide vapor is typically generated by vacuum vaporization. Among other benefits, hydrogen peroxide vapor typically has a rapid cycle time (e.g., 30-45 minutes), can be effective at low temperature (e.g., 20 °C), and produces environmentally safe by-products (water, oxygen). In addition, hydrogen peroxide vapor has generally fair material compatibility and ease of operation. However, hydrogen peroxide vapor can be reactive with selected polymers and has not been cleared by the FDA for sterilization of medical devices. On the other hand, ozone can be used as a sterilizing gas, which is relatively effective, even at low temperatures. Unfortunately, ozone is chemically very unstable and may be reactive with biologies. Furthermore, generation of quantities sufficient for sterilization typically requires dedicated equipment.

[0007] In addition, none of the currently known sterilization systems and methods are readily adaptable for safe field- or point-of-care use as these systems typically require specialized equipment and/or present a health hazard to the operator or environment. Moreover, currently known sterilization devices will typically require in most cases electricity to operate.

[0008] Thus, even though various devices and methods of sterilizing objects are known in the art, all or almost all of them suffer from several drawbacks, particularly where the sterilizing agent is toxic and/or is delivered at elevated temperatures. Therefore, there remains a need for improved devices and methods that allow for sterilization in a safe and efficient manner.

Summary of The Invention

[0009] The inventive subject matter is directed to devices and methods of sterilizing an object in a safe and conceptually simple manner in which the object is sealed in a container that includes a nitric oxide permeable microbial barrier that allows for permeation of nitric oxide into the container to reach sterilizing conditions within the container.

[0010] In one aspect of the inventive subject matter, the inventor contemplates a kit that comprises a first container that is configured to receive and sealingly enclose an object and a second container that is configured to sealingly enclose the first container. It is further generally contemplated that the first container comprises a nitric oxide permeable microbial barrier, wherein the nitric oxide permeable microbial barrier has a permeability for nitric oxide sufficient to allow for a sterilizing nitric oxide concentration in the first container when the second container contains nitric oxide at or above the sterilizing nitric oxide concentration.

[0011] In some embodiments, the first container can be sealed via an adhesive seal, a heat seal, a snap fit seal, a clamp seal, or a threaded seal, and/or it is preferred (but not necessary) that the first container is flexible. Where desired, at least a portion of the first container may be transparent or include a transparent portion. Moreover, it should be recognized that the second container may be configured to sealingly enclose at least one additional first container. While not limiting to the inventive subject matter, especially contemplated objects will relate to the field of medicine and may therefore include medical devices, surgical or dental tools, various implants, catheter, and/or trocars, an IV set, or biologies products.

[0012] In further embodiments, the nitric oxide permeable microbial barrier comprises a porous breathable film, and especially contemplated porous breathable films include perforated films, composite films of a microporous polymer and an inorganic filler, and non-woven polymer fiber webs. For example, the first container may be configured as a pouch that comprises on one side a non-woven polymer fiber web as the nitric oxide permeable microbial barrier and on the other side a transparent PET/LDPE polyester film. Alternatively, or additionally, the nitric oxide permeable microbial barrier may also comprise a non-porous breathable film. Among other suitable options, contemplated non-porous breathable films include polyurethane polymers, poly(N-isopropylacrylamide) polymers, side-chain crystalline polymers, and polymer composites comprising a paraffin wax.

[0013] Regardless of the type of the nitric oxide permeable microbial barrier, it is typically preferred that the nitric oxide permeable microbial barrier has an apparent diffusion coefficient for nitric oxide of at least 0.2 x 10^-5 cm²/s, or of at least 1.0 x 10^-5 cm²/s. Moreover, it is contemplated that the sterilizing nitric oxide concentration is a steady-state concentration of nitric oxide of between 1 and 50 ppb.

[0014] Where desired, the second container may contain a nitric oxide releasing source, which may or may not be coupled to or form part of the second container. For example, suitable nitric oxide releasing sources may comprise S-nitroso-N-acetyl-D-penicillamine (SNAP), a nitrite, an S-nitrosothiol, S-nitrosocysteine, 5-nitrosoglutathione, a diazeniumdiolate compound, arginine, an organitrite, or a biological source adapted to generate nitric oxide. As will be readily appreciated, such nitric oxide releasing sources may be contained in a separate container, or may be coupled to a carrier, or may be covalently bound to a polymer. Depending on the type of the nitric oxide releasing source, it should be appreciated that the source may release nitric oxide upon irradiation with light.

[0015] In still further embodiments, the first and/or second container may also include a carrier that contains a chromophore that undergoes a color change in the presence of nitric oxide, and exemplary chromophores include 2,2’-azinobis(3-ethylbenzothiazoline-6-sulfonic acid), methyl orange, or thymol blue.

[0016] Therefore, in another aspect of the inventive subject matter, the inventor also contemplates a method of sterilizing an object that includes a step of placing the object into a first container and then sealing the first container, wherein the first container comprises a nitric oxide permeable microbial barrier. Such method will further include a step of placing the sealed first container into a second container and sealing the second container to thereby enclose the sealed first container within the second container. In yet another step, nitric oxide is then fed into or generated in the second container to at least a sterilizing nitric oxide concentration. Most typically, the nitric oxide permeable microbial barrier has a permeability for nitric oxide sufficient to allow for a sterilizing nitric oxide concentration in the first container when the second container contains nitric oxide at or above the sterilizing nitric oxide concentration. Consequently, in yet another step of contemplated methods the object is exposed in the first container to the sterilizing nitric oxide concentration for a time sufficient to sterilize the object.

[0017] In some embodiments, the first and/or second containers are sealed using an adhesive seal, a heat seal, a snap fit seal, a clamp seal, or a threaded seal. Moreover, it is contemplated that the first and/or second containers are flexible. As noted above, at least a portion of the first container may be transparent, and/or the second container may be configured to sealingly enclose at least one additional first container. While not limiting to the inventive subject matter, especially contemplated objects will relate to the field of medicine and may therefore include medical devices, surgical or dental tools, various implants, catheter, and/or trocars, an IV set, or biologies products.

[0018] With respect to the nitric oxide permeable microbial barrier, the sterilizing nitric oxide concentration, the nitric oxide releasing source, and the carrier containing a chromophore, the same considerations as provided above apply and are not reiterated here.

[0019] Consequently, the inventor also contemplates a method of contactless sterilizing an object that includes a step of exposing the object to a sterilizing nitric oxide concentration for a time sufficient to sterilize the object, wherein, during the step of exposing, (a) the object is sealed into a first container that comprises a nitric oxide permeable microbial barrier, and (b) nitric oxide is delivered to the object across the nitric oxide permeable microbial barrier.

[0020] Most typically, but not necessarily, the sterilizing nitric oxide concentration is a steadystate concentration of nitric oxide of between 1 and 50 ppb, the time is between 20 and 240 minutes, and/or the object is exposed to the sterilizing nitric oxide concentration at a temperature of between 20 and 50 °C. With respect to the nitric oxide permeable microbial barrier and the sterilizing nitric oxide concentration, the same considerations as provided above apply and are not reiterated here.

[0021] Moreover, in most typical embodiments, the first container is contained in a second sealed container during the step of exposing. As will be appreciated, nitric oxide may then be fed into or generated in the second container from a nitric oxide releasing source as discussed above. Where desired, a color change may be detected in a chromophore (typically coupled to a carrier and located within the first container) to so ascertain presence of nitric oxide. Sterility of the object is achieved in the above methods using the above devices and can be verified or tested according to ASTM E1766-15.

[0022] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components. Brief Description of The Drawing

[0023] FIG.l is a photograph of a nitric oxide indicator sealed inside a polymer film/Tyvek sealed pouch as seen through a transparent film of the pouch and a nitric oxide indicator outside the sealed pouch before exposure to nitric oxide.

[0024] FIG.2 is a photograph of the nitric oxide indicator of FIG.l sealed inside a polymer film/Tyvek sealed pouch and the nitric oxide indicator of FIG.1 outside the sealed pouch after exposure to nitric oxide.

Detailed Description

[0025] The inventor has discovered that objects in a container can be sterilized with nitric oxide where the container includes a permeable microbial barrier that allows for permeation of nitric oxide into the container in an amount sufficient to a steady-state concentration of nitric oxide that is effective to sterilize the object.

[0026] Advantageously, the systems and methods contemplated herein allow for a simple and effective sterilization process in which the object can be sterilized in a contactless manner and in which the object can be maintained in a closed container that prevents contamination of the object after sterilization. Still further, sterilization of the object with nitric oxide using such systems and methods can be performed at desirably low temperatures (e.g., between 20-50 °C) and at ambient pressure (e.g, about 1 bar), and can be concluded within relatively short time (e.g., between 30-180 min).

[0027] To that end, it is generally contemplated that contactless sterilization of an object will be performed in a closed container that comprises a nitric oxide permeable microbial barrier. Most typically, the nitric oxide permeable microbial barrier has a permeability for nitric oxide that is sufficient to allow for a sterilizing nitric oxide concentration in the container when the container is in an environment that contains nitric oxide at or above the sterilizing nitric oxide concentration. With regard to sterilizing nitric oxide concentration, it should be appreciated that the exact concentration will depend on various factors, including the type and quantity of microbial contamination present, the surface and geometry of the object to be sterilized, etc. However, it is generally contemplated that the sterilizing nitric oxide concentration will be a steady-state concentration of nitric oxide of between 1 and 50 ppb, or greater. [0028] Consequently, to achieve a desirably short time to achieve sterilizing nitric oxide concentrations in the closed container, the nitric oxide permeable microbial barrier will typically have an apparent diffusion coefficient for nitric oxide of at least 0.01 x IO’⁵ cm²/s, and more typically at least 0.05 x 10^-5 cm²/s, or at least 0.75 x 10^-5 cm²/s, or at least 0. 1 x 10^-5 cm²/s, or at least 0.25 x 10^-5 cm²/s, or at least 0.40 x 10^-5 cm²/s, or at least 0.50 x 10^-5 cm²/s, or at least 0.60 x 10^-5 cm²/s, or at least 0.70 x 10^-5 cm²/s, or at least 0.8 x 10^-5 cm²/s, or at least 0.9 x 10’⁵ cm²/s, or at least 1.0 x 10^-5 cm²/s, or at least 1.2 x 10^-5 cm²/s, or at least 1.4 x 10^-5 cm²/s, or at least 1.6 x 10^-5 cm²/s, or at least 1.8 x 10^-5 cm²/s, or at least 2.0 x 10^-5 cm²/s, or at least 2.25 x 10^-5 cm²/s, or at least 2.5 x 10^-5 cm²/s, or at least 2.75 x 10^-5 cm²/s, or at least 3.0 x 10^-5 cm²/s. Therefore, suitable nitric oxide permeable microbial barrier will typically have an apparent diffusion coefficient for nitric oxide of between 0.05 x 10^-5 cm²/s and 0.5 x 10^-5 cm²/s, or between 0.5 x 10^-5 cm²/s and 1.5 x 10^-5 cm²/s, or 1.0 x 10^-5 cm²/s and 3.0 x 10^-5 cm²/s.

[0029] As will be readily appreciated, the type of suitable materials may vary considerably so long the material has the above permeability to nitric oxide, and so long as the material forms a microbial barrier. With regard to the permeability for nitric oxide, there are numerous test methods known in the art, and an exemplary test method suitable for use herein is found at ACS Biomater. Sci. Eng. 2016, 2, 1483-1492, incorporated by reference herein. Similarly, with regard to the microbial barrier properties, there are numerous test methods known in the art, and an exemplary test method suitable for use herein is ASTM F2638 (Standard Test Method for Using Aerosol Filtration for Measuring the Performance of Porous Packaging Materials as a Surrogate Microbial Barrier).

[0030] Therefore, nitric oxide permeable microbial barriers suitable for use herein include various porous and non-porous breathable films. For example, porous breathable films will typically include (laser or microneedle) perforated films, composite films made from one or more fillers in a microporous polymer, and various non-woven polymer fiber webs. Similarly, where the nitric oxide permeable microbial barrier is a non-porous breathable film, suitable films include various polyurethane polymers, poly(N-isopropylacrylamide) polymers, sidechain crystalline polymers, and polymer composites comprising a paraffin wax. Additional polymers and suitable parameters are described in Trends in Food Science & Technology, Volume 76, 2018, Pages 15-27, incorporated by reference herein.

[0031] Viewed from a different perspective, suitable nitric oxide permeable microbial barriers may be made from a wide variety of natural and synthetic polymers such as silicone rubber, polyurethane, Tyvek, PVC, EVA, polyesters, polycarbonates, thermoplastic polyurethanes, polylactic acid, polycaprolactone, cellulose, and copolymers and combinations thereof. Moreover, these polymers may be microporous, form a porous web, or have permeability to nitric oxide at elevated temperatures or mechanical stress, etc. Additionally, it is contemplated that all microbial barriers are deemed suitable for use herein that are suitable for use with packaging materials for content that is sterilized with ethylene oxide.

[0032] As will be readily appreciated, the particular nature of the object that is to be sterilized can vary greatly. However, it is especially contemplated that the object is for use in medicine, and as such will typically include various medical devices, surgical or dental tools, implants, catheters, IV sets, wound dressings, sutures, staples, and biologies (which may or may not be coupled to an implantable or injectable material). Other non-medical uses include sterilization of cosmetic formulations, containers, food items and/or items used in the preparation of food, as well as common household goods (e.g., toothbrushes and toothbrush heads) and items used with infant care (e.g., bottles, nipples, pacifiers, etc.).

[0033] Consequently, the configuration of the container that contains the object for sterilization can vary considerably so long as the container includes the nitric oxide permeable microbial barrier as described above and so long as such container can be sealed to retain the sterile object without risk for inadvertent contamination of the object. In some embodiments, such as with containers for household goods, the container may be a relatively rigid container with a screw top that includes the nitric oxide permeable microbial barrier. On the other hand, where the object is used in medicine, the container may be configured as a single-use pouch that will comprise on one side a non-woven polymer fiber web as the nitric oxide permeable microbial barrier and on another side a transparent PET/LDPE polyester film (which may be heat sealed together and which may be sealed shut after placement of the object into the pouch. In view of the above, it should therefore be appreciated that the nitric oxide permeable microbial barrier may form a part of the container structure e.g., a wall or side of a pouch), or that the nitric oxide permeable microbial barrier may be coupled to a frame or carrier or otherwise affixed (e.g., glued, sewn, welded, etc.) to at least a portion of the container. Moreover, it should be noted that the nitric oxide permeable microbial barrier may be permanently coupled to the container (e.g., in most single-use embodiments) or that the nitric oxide permeable microbial barrier may be removably coupled to the container (e.g., in most multi-use embodiments). For example, where the nitric oxide permeable microbial barrier is removably coupled to the container, the nitric oxide permeable microbial barrier may be re-used or replaced with a fresh nitric oxide permeable microbial barrier.

[0034] Suitable container volumes (after placement of the object) will be between 1 and 10 cm³, or between 10 and 50 cm³, or between 50 and 500 cm³, or between 500 cm³ and 5,000 cm³, and even bigger. Likewise, contemplated containers may be flexible (deformable using manual force, will not retain shape after application of force) or rigid (not deformable using manual force, will retain shape after application of force), or include a flexible portion. Moreover, it is also contemplated that in some embodiments the container will include a visually transparent portion through which the content of the container is at least partially visible, and/or through which color change of a chromogen can be observed. Therefore, the containers contemplated herein will be configured to receive a single object or multiple objects for sterilization.

[0035] As will be readily appreciated, suitable manners of sealingly closing the container will vary greatly. For example, after receiving the object in the container, the container can be sealed using an adhesive seal, a heat seal, a snap fit seal, a clamp seal, or a threaded seal, etc. Thus, the seal of the container may be a permanent seal or a reusable seal, which may form an integral part of the container, or which may be external to the container.

[0036] Depending on the particular use it should be appreciated that the nitric oxide can be provided to the object sealed in the container in a variety of manners. Most typically, however, the sealed container with the object is placed in a secondary outer container into which nitric oxide can then be delivered from an external nitric oxide source or a nitric oxide source is placed inside the secondary container from which the nitric oxide is produced or released after the secondary container is sealed. Therefore, it should be noted that the container with the object need not contain any source for nitric oxide or valve structure to receive the nitric oxide. Instead, nitric oxide is delivered to the object from the outside of the container via the nitric oxide permeable microbial barrier.

[0037] Among other suitable nitric oxide sources, it is generally contemplated that the nitric oxide is provided as a (typically pure (e.g., purity at least 90 mol%, or at least 95 mol%, or at least 98 mol%)) gas from a gas storage such as a compressed gas cylinder, or generated in situ from the decomposition of a precursor chemical that may be decomposed via thermal, via light irradiation (photolytic cleavage), via pH change, via electrochemical reaction, or via enzymatic methods to generate nitric oxide as a reaction product. Moreover, it is generally preferred that the nitric oxide source will generate nitric oxide as the only reactive species to avoid otherwise undesirable chemical interaction with the object to be sterilized.

[0038] Therefore, suitable nitric oxide sources include nitric oxide donating polymers that use different nitric oxide moieties and different polymer base materials. In some embodiments, the nitric oxide donors can be covalently linked to the polymer or blended into the polymer. Moreover, nitric oxide donors can also be used in solid, liquid, or gel forms. Among other choices, especially contemplated nitric oxide sources include 5-nitroso-A-acetyl-D- penicillamine (SNAP), nitrite salts, 5-nitrosocysteine, 5-nitrosoglutathione, diazeniumdiolate compounds, arginine (via enzymatic action), and various organonitrites. Non-limiting examples of suitable S-nitroso-N-acetyl-D-penicillamines and other photosensitive S- nitrosothiols covalently attached to polymers are described in U.S. Pat. No. 9,884,943 B2 and International Publication No. WO 2020/018488 Al, both of which are incorporated by reference herein.

[0039] Other examples of nitric oxide sources include gas phase delivery from polymers, acidified nitrite or nitrate, nitric oxide donating molecules such as diazeniumdiolates, nitrosothiols, nitrosyl compounds, or other methods of NO generation such as enzymatic production of nitric oxide, chemical production of nitric oxide from ascorbic acid or metal catalysis, electrochemical production of nitric oxide, photolytic cleavage of bonds to release nitric oxide, direct delivery of nitric oxide gas, etc. Further considerations and compositions suitable for use herein are described in WO 2022/164894, incorporated by reference herein.

[0040] Regardless of the particular source of the nitic oxide, it is generally contemplated that the source and/or container are configured such as to generate at least a sterilizing nitric oxide concentration within the container that encloses the object and the outer container that encloses the container with the object. In most embodiments, the sterilizing nitric oxide concentration will be a steady-state concentration of nitric oxide of between 1 and 500 ppb, or between 1 and 10 ppb, or between 10-50 ppb, or between 50 and 250 ppb, or between 250 ppb and 500 ppb, or even more. Therefore, suitable sterilizing nitric oxide concentrations will be at 1 ppb, or at least 5 ppb, or at least 10 ppb, or at least 50 ppb, or at least 100 ppb, or at least 200 ppb, and even higher. [0041] In view of the above, it should therefore be noted that the secondary (outer) container may be configured such as to enclose only a single inner container that encloses the object, or that the secondary (outer) container may be configured such as to enclose only multiple inner containers that each enclose one or more object for sterilization. Accordingly, the secondary container may be a room that can be closed to so maintain a sterilizing nitric oxide concentration, or may be an enclosure, chest, or otherwise configured container that has a door that allows for a sealing closure. In still further contemplated aspects, the secondary container may also be a bag or pouch that receives the inner container with the object, wherein the outer container can be sealed or clamped shut. Therefore, the ratio of inner volumes of the outer container to a single inner container may be at least 1.5:1, or at least 2:1, or at least 3:1, or at least 5:1, or at least 10: 1, or at least 50: 1, or at least 100: 1 and even higher.

[0042] Viewed from a different perspective, it should therefore be appreciated that the nature and type of sterilization may dictate at least to some degree the configuration of the inner and outer containers. For example, where the sterilization is performed in a sterilization facility of a hospital, the outer container may be a room or relatively large container (e.g. , having an inner volume of at least 5 m³,) that encloses a large number of inner containers (e.g., at least 200). On the other hand, where the sterilization is performed in a dental or medical office, the outer container may be a mid-sized enclosure e.g., having an inner volume of less than 2 m³) that encloses a moderate number (e.g., between 10-50) of inner containers. Moreover, where the sterilization is performed at a point-of-care or in the field, the outer container may be a pouch or bag (e.g., having an inner volume of at between 10-500 cm³) that encloses a single inner container. Similarly, where the sterilization is performed in a domestic setting for a household good, the outer container may be a box (e.g., having an inner volume of between 100-5,000 cm³) that encloses a small number of inner containers (e.g., between 1-5).

[0043] In still further contemplated aspects, the outer container may or may not include one or more elements to control one or more environmental parameters, which will to at least some degree influence the duration required to ensure sterility of the object. For example, the outer container may comprise thermal insulation materials, a heating and/or cooling circuit, an energy source to promote nitric oxide release/cleavage from a precursor material, and/or may be coupled to a system that increases pressure in the outer container.

[0044] As will be readily appreciated, sterilization of the object in the inner container will typically depend at least in part on the concentration of the nitric oxide in the outer and inner container, the temperature, pressure, and duration of exposure. However, it is generally contemplated that using the systems and methods presented herein, sterilization can be performed at a temperature of between 10-20 °C, or between 15-25 °C, or between 15-30 °C, or between 20-40 °C, or between 15-45 °C, or between 15-50 °C, or between 20-55 °C. Thus, suitable sterilization temperatures will typically be at least 10 °C, or at least 15 °C, or at least 20 °C, or at least 25 °C, or at least 30 °C, or at least 35 °C, or at least 40 °C, or at least 45 °C, or at least 50 °C, but preferably less than 60 °C, or less than 55 °C, or less than 50 °C, or less than 45 °C, or less than 40 °C. Similarly, it is generally preferred that the pressure of the sterilization will be at ambient pressure, but elevated pressures such as at least 0.1 barg, or at least 0.2 barg, or at least 0.5 barg, or at least 1.0 barg, or at least 2 barg are also expressly contemplated herein. In addition, it should be noted that the time it takes for sterilization of the object in the inner container can be at least 10 minutes, or at least 20 minutes, or at least 40 minutes, or at least 60 minutes, or at least 120 minutes, or at least 180 minutes, or at least 300 minutes, but preferably less than 240 minutes, or less than 210 minutes, or less than 150 minutes, or less than 90 minutes, or less than 30 minutes.

[0045] While in some embodiments sterilization can follow a specific protocol to ascertain sterility, it is also contemplated that a sterility indicator can be included in the inner (and in some cases also outer) container that will indicate sterility. For example, especially contemplated sterility indicators include dyes that are reactive with nitric oxide, and especially nitric oxide reactive chromophores that change color upon exposure to nitric oxide. For example, suitable the chromophores include 2,2’-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), methyl orange (MeORG), thymol blue (ThBlu), and any reasonable combination thereof. Such chromophores may be coupled to a carrier, or a carrier may be impregnated with the chromophore. As will be readily appreciated, the carrier may further include a layer covering the chromophore to control diffusion of the nitric oxide to the chromophore and/or a base layer (which may or may not comprise a low-tack adhesive) that allows affixing the carrier to the object or an inside portion of the inner container. Among other options, especially suitable sterility indicator devices and compositions are described in WO 2022/164905, which is incorporated by reference herein.

[0046] Of course, it should be recognized that the sterility of the object achieved in the above methods using the above devices and can be verified or tested according to ASTM E1766-15. Thus, and viewed for a different perspective, the reduction in viable microbial count of an object sterilized using the systems, devices, and methods presented herein will be at least one order of magnitude, and more typically at least two orders, or at least three orders, or at least four orders, or at least five orders, or at least six orders of magnitude after sterilization as compared to before sterilization. Advantageously, and as already discussed above, sterilization can be performed at ambient pressure, moderate to low temperatures (e.g., 20-24 °C), and in a relatively short time e.g., 20-60 min). Moreover, once sterilized, the object can remain in the container and will be protected from external microbial contamination.

Examples

[0047] To validate the concept of contactless sterilization of objects with nitric oxide, the inventor tested a commercially available packaging container (Oliver Healthcare packaging, Grand Rapids, MI 49504) that was configured as a pouch having one side made from a nonwoven polymer fiber web (Tyvek 1073B) as the nitric oxide permeable microbial barrier that acted as a porous breathable film. The other side was made from a flexible and transparent a transparent PET/LDPE polyester film (TPF-0501A 48 PET/200 LDPE) and thermally sealed to the non-woven polymer fiber web to allow visualization of the contents in the container. To test permeation of nitric oxide across the non-woven polymer fiber web, the inventor placed a paper strip that was treated with ABTS (2,2’-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)), which acts as a chromophore that turns green upon exposure to nitric oxide. The test container was then heat sealed to enclose the test strip and a second test strip was provided as external control. Both the sealed container and the external test strip were then sealed into a secondary plastic bag that contained a PDMS polymer strip that contained S-nitroso-N-acetyl- D-penicillamine (SNAP -PDMS) as a source material for nitric oxide release.

[0048] FIG.l is a photograph depicting the indicator strip sealed in the pouch and a second indicator strip outside the pouch before placing the pouch and the second strip into a secondary bag. As can be seen from FIG.1, both indicator strips were of the same color and did not show exposure to nitric oxide. The SNAP -PDMS was then irradiated with light to produce nitric oxide in the secondary plastic pouch, and the setup was maintained at room temperature (25 °C for 16 hours). As can be clearly seen from FIG.2, both indicator strips were colored deep green demonstrating exposure to nitric oxide. In this context, it should be noted that the first indicator strip was still contained within the sealed package, and that both strips were colored with the same intensity. This experiment clearly demonstrates that an object in a pouch as disclosed herein can be sterilized by contactless sterilization. [0049] In some embodiments, the numbers expressing quantities of ingredients, properties such as concentration, reaction conditions, and so forth, used to describe and claim certain embodiments of the invention are to be understood as being modified in some instances by the term “about.” As used herein, the terms "about" and "approximately", when referring to a specified, measurable value (such as a parameter, an amount, a temporal duration, and the like), is meant to encompass the specified value and variations of and from the specified value, such as variations of +/-10% or less, alternatively +/-5% or less, alternatively +/-1% or less, alternatively +/-0.1% or less of and from the specified value, insofar as such variations are appropriate to perform in the disclosed embodiments. Thus, the value to which the modifier "about" or "approximately" refers is itself also specifically disclosed. The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein.

[0050] All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.

[0051] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise. As also used herein, and unless the context dictates otherwise, the term "coupled to" is intended to include both direct coupling (in which two elements that are coupled to each other contact each other) and indirect coupling (in which at least one additional element is located between the two elements). Therefore, the terms "coupled to" and "coupled with" are used synonymously.

[0052] It should be apparent to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the scope of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification or claims refer to at least one of something selected from the group consisting of A, B, C .... and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc.

Claims

CLAIMS What is claimed is:

1. A kit comprising: a first container configured to receive and sealingly enclose an object; a second container configured to sealingly enclose the first container; wherein the first container comprises a nitric oxide permeable microbial barrier; and wherein the nitric oxide permeable microbial barrier has a permeability for nitric oxide sufficient to allow for a sterilizing nitric oxide concentration in the first container when the second container contains nitric oxide at or above the sterilizing nitric oxide concentration.

2. The kit of claim 1, wherein the first container is sealable via an adhesive seal, a heat seal, a snap fit seal, a clamp seal, or a threaded seal.

3. The kit of claim 1, wherein the first container is flexible, and/or wherein at least a portion of the first container is transparent.

4. The kit of claim 1, wherein the first and/or the second container has an inner volume between 10 cm³ and 1,000 cm³.

5. The kit of claim 1, wherein the second container is configured to sealingly enclose another first container, and/or wherein the second container is configured to enclose the first container via an adhesive seal, a heat seal, a snap fit seal, a clamp seal, or a threaded seal.

6. The kit of claim 1, wherein the object is a medical device, a surgical or dental tool, an implant, a catheter, an IV set, or a biological product.

7. The kit as in one of claims 1-6, wherein the nitric oxide permeable microbial barrier comprises a porous breathable film.

8. The kit of claim 7, wherein the porous breathable film comprises a perforated film, a composite film of a microporous polymer and an inorganic filler, or a non-woven polymer fiber web.

9. The kit of claim 1, wherein the first container is configured as a pouch that comprises on at least one side a non-woven polymer fiber web as the nitric oxide permeable microbial barrier and on another side a transparent PET/LDPE polyester film

10. The kit of any one of claims 1-6, wherein the nitric oxide permeable microbial barrier comprises a non-porous breathable film.

11. The kit of claim 10, wherein the non-porous breathable film comprises a polyurethane polymer, a poly(N-isopropylacrylamide) polymer, a side-chain crystalline polymer, or a polymer composite comprising a paraffin wax.

12. The kit of claim 1, wherein the nitric oxide permeable microbial barrier has an apparent diffusion coefficient for nitric oxide of at least 0.2 x 10^-5 cm²/s.

13. The kit of claim 1, wherein the nitric oxide permeable microbial barrier has an apparent diffusion coefficient for nitric oxide of at least 1.0 x 10^-5 cm²/s.

14. The kit of claim 1, wherein the sterilizing nitric oxide concentration is a steady-state concentration of nitric oxide of between 1 and 50 ppb.

15. The kit of claim 1, wherein the second container contains a nitric oxide releasing source

16. The kit of claim 15, wherein the nitric oxide releasing source is coupled to the second container, and/or wherein the nitric oxide releasing source is replaceable upon depletion.

17. The kit of claim 15, wherein the nitric oxide releasing source comprises S-nitroso-N-acetyl- D-penicillamine (SNAP), a nitrite, an S-nitrosothiol, 5-nitrosocysteine, S- nitrosoglutathione, a diazeniumdiolate compound, arginine, an organitrite, or a biological source adapted to generate nitric oxide, and optionally wherein the nitric oxide releasing source is coupled to a polymer.

18. The kit of claim 15, wherein the nitric oxide releasing source releases nitric oxide upon irradiation with visible or UV light.

19. The kit of claim 1, wherein the first and/or second container further comprise a carrier containing a chromophore that undergoes a color change in the presence of nitric oxide.

20. The kit of claim 19, wherein the chromophore is 2,2’-azinobis(3-ethylbenzothiazoline-6- sulfonic acid), methyl orange, or thymol blue.

21. A method of sterilizing an object, comprising: placing the object into a first container and then sealing the first container, wherein the first container comprises a nitric oxide permeable microbial barrier; placing the sealed first container into a second container and sealing the second container to thereby enclose the sealed first container within the second container; feeding into or generating in the second container nitric oxide to at least a sterilizing nitric oxide concentration; wherein the nitric oxide permeable microbial barrier has a permeability for nitric oxide sufficient to allow for a sterilizing nitric oxide concentration in the first container when the second container contains nitric oxide at or above the sterilizing nitric oxide concentration; and exposing the object in the first container to the sterilizing nitric oxide concentration for a time sufficient to sterilize the object.

22. The method of claim 21, wherein the first container is sealed using an adhesive seal, a heat seal, a snap fit seal, a clamp seal, or a threaded seal.

23. The method of claim 21, wherein the first container is flexible, and/or wherein at least a portion of the first container is transparent.

24. The method of claim 21, wherein the first and/or the second container has an inner volume between 10 cm³ and 1,000 cm³.

25. The method of claim 21, wherein the second container is configured to enclose another first container, and/or wherein the second container is sealed using an adhesive seal, a heat seal, a snap fit seal, a clamp seal, or a threaded seal.

26. The method of claim 21, wherein the object is a medical device, a surgical or dental tool, an implant, a catheter, an IV set, or a biological product.

27. The method of claim 21, wherein the nitric oxide permeable microbial barrier comprises a porous breathable film.

28. The method of claim 27, wherein the porous breathable film comprises a perforated film, a composite film of a microporous polymer and an inorganic filler, or a non-woven polymer fiber web.

29. The method of claim 21, wherein the first container is configured as a pouch that comprises on one side a non-woven polymer fiber web as the nitric oxide permeable microbial barrier and on another side a transparent PET/LDPE polyester film.

30. The method of claim 21, wherein the nitric oxide permeable microbial barrier comprises a non-porous breathable film.

31. The method of claim 30, wherein the non-porous breathable film comprises a polyurethane polymer, a poly(N-isopropylacrylamide) polymer, a side-chain crystalline polymer, or a polymer composite comprising a paraffin wax.

32. The method of claim 21, wherein the nitric oxide permeable microbial barrier has an apparent diffusion coefficient for nitric oxide of at least 0.2 x 10^-5 cm²/s.

33. The method of claim 21, wherein the nitric oxide permeable microbial barrier has an apparent diffusion coefficient for nitric oxide of at least 1.0 x 10^-5 cm²/s.

34. The method of claim 21, wherein the sterilizing nitric oxide concentration is a steady-state concentration of nitric oxide of between 1 and 50 ppb, and/or wherein the time sufficient to sterilize the object is between 20 and 240 minutes.

35. The method of claim 21, wherein the second container contains a nitric oxide releasing source.

36. The method of claim 35, wherein the nitric oxide releasing source is coupled to the second container or wherein the nitric oxide releasing source is replaceable upon depletion.

37. The method of claim 35, wherein the nitric oxide releasing source comprises S-nitroso-N- acetyl-D-penicillamine (SNAP), a nitrite, an S-nitrosothiol, 5-nitrosocysteine, S- nitrosoglutathione, a diazeniumdiolate compound, arginine, an organitrite, or a biological source adapted to generate nitric oxide, and optionally wherein the nitric oxide releasing source is coupled to a polymer.

38. The method of claim 35, wherein the nitric oxide releasing source releases nitric oxide upon irradiation with visible or UV light.

39. The method of any one of the preceding claims, wherein the first and/or second container further comprise a carrier containing a chromophore that undergoes a color change in the presence of nitric oxide.

40. The method of claim 39, wherein the chromophore is 2,2’-azinobis(3-ethylbenzothiazoline- 6-sulfonic acid), methyl orange, or thymol blue.

41. A method of contactless sterilizing an object, comprising: exposing the object to a sterilizing nitric oxide concentration for a time sufficient to sterilize the object; wherein, during the step of exposing, (a) the object is sealed into a first container that comprises a nitric oxide permeable microbial barrier, and (b) nitric oxide is delivered to the object across the nitric oxide permeable microbial barrier.

42. The method of claim 41, wherein the sterilizing nitric oxide concentration is a steady-state concentration of nitric oxide of between 1 and 50 ppb.

43. The method of claim 41, wherein the time is between 20 and 240 minutes.

44. The method of claim 41, wherein the object is exposed to the sterilizing nitric oxide concentration at a temperature of between 20 and 50 °C.

45. The method of claim 41, wherein the nitric oxide permeable microbial barrier comprises a porous breathable film.

46. The method of claim 45, wherein the porous breathable film comprises a perforated film, a composite film of a microporous polymer and an inorganic filler, or a non-woven polymer fiber web.

47. The method of claim 41, wherein the first container is configured as a pouch that comprises on one side a non-woven polymer fiber web as the nitric oxide permeable microbial barrier and on another side a transparent PET/LDPE polyester film.

48. The method of claim 41, wherein the nitric oxide permeable microbial barrier comprises a non-porous breathable film.

49. The method of claim 48, wherein the non-porous breathable film comprises a polyurethane polymer, a poly(N-isopropylacrylamide) polymer, a side-chain crystalline polymer, or a polymer composite comprising a paraffin wax.

50. The method of claim 41 , wherein during the step of exposing, the first container is contained in a second sealed container.

51. The method of claim 50, further comprising a step of feeding into or generating in the second container nitic oxide.

52. The method of claim 51, wherein the nitric oxide is generated in the second container from a nitric oxide releasing source, and/or wherein the nitric oxide releasing source is replaceable upon depletion.

53. The method of claim 41, further comprising detecting a color change in a chromophore that is coupled to a carrier and that is located within the first container, wherein the color change indicates presence of nitric oxide.

54. The method of claim 53, wherein the chromophore is 2,2’-azinobis(3-ethylbenzothiazoline- 6-sulfonic acid), methyl orange, or thymol blue.

55. The method of any one of claims 41-52, wherein the object is sterile according to ASTM E1766-15.