Systems and methods for carrier systems for controlled release delivery in perishable articles

Abstract

A delivery system for reducing decomposition of perishable articles, the system comprising one or more compositions comprising at least one active compound and at least one inactive compound, and at least one carrier configured to support the one or more compositions, wherein the at least one carrier comprises a release rate change mechanism, wherein the release rate change mechanism is configured to modulate a release rate of the one or more compositions.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Application No. 63 / 378,309, filed on October 4, 2022, the entire disclosure of which is hereby incorporated by reference. Background Art

[0002] Various volatile compounds such as essential oil compounds are known to have antifungal activity and can help extend the shelf life of perishable items by inhibiting spoilage. Preventing spoilage over a certain duration requires releasing the compound into the environment in a continuous and predictable manner so as to maintain the desired concentration of the compound in the gas phase. In addition to volatile compounds with antifungal activity, other volatile compounds such as 1-MCP used in the environment of perishable items such as climacteric fruits can also work synergistically to extend the shelf life of perishable agricultural products.

[0003] Therefore, there is a need for systems and methods for controlling the release rate of active compounds to extend the shelf life of perishable items. Summary of the invention

[0004] This Summary is provided to introduce some concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0005] The technology disclosed and / or claimed herein is generally directed to one or more delivery systems for delivering one or more active compounds to reduce the decomposition of perishables. To prevent the perishables from spoiling over a period of time, it is necessary to release the one or more active compounds in a continuous and predictable manner so as to maintain a desired concentration of the one or more active compounds in the gas phase in the environment of the perishables. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The foregoing aspects and many of the attendant advantages of the present invention will become more readily explained as the same become better understood with reference to the following detailed description when taken in conjunction with the accompanying drawings, wherein: FIG1A illustrates an example compound according to the present technology; FIG. 1B is a graph of properties of the example compound of FIG. 1A in accordance with the present technology; 2A to 2I are example carriers according to the present technology; FIG3 is an example diffusion cell according to the present technology; FIG4 is a test fixture according to the present technology; 5 is a graph illustrating diffusion through an example membrane in accordance with the present technology; 6 is a graph illustrating diffusion through another example membrane in accordance with the present technology; 7 is a graph showing the vapor pressure of a wax carrier according to the present technology; 8 is a graph showing the vapor pressure of a PP film carrier according to the present technology; FIG9 shows the evolution of vapor pressure over time measured in the same leaking container according to the present technology; FIG10 is an example geometry of a carrier used for simulation according to the present technology; FIG. 11 shows the concentration distribution of volatiles in a solid rectangular carrier matrix according to the present technology, wherein the diffusion rate of the volatiles within the matrix is ​​different; 12 is a graph of different release profiles that would be observed in a cartridge from the matrix of FIG. 11 in accordance with the present technology; FIG13 shows the concentration distribution of volatiles in rectangular carriers of different sizes according to the present technology; 14 is a graph of different release profiles from the cartridges of matrices of different sizes from FIG. 13 in accordance with the present technology; FIG15 shows the construction of a carrier having a multi-layer construction according to the present technology; FIG. 16 shows the concentration distribution of volatiles in a carrier having outer layers with different diffusivities but the same thickness according to the present technology; 17 is a graph of different release profiles from a cartridge of the carrier of FIG. 16 in accordance with the present technology; FIG18 shows the concentration distribution of volatiles in a solid rectangular carrier matrix according to the present technology; 19 is a graph of different release profiles from the cartridge of the matrix of FIG. 18 in accordance with the present technology; FIG20 shows the concentration distribution of volatiles of different shapes according to the present technology; FIG21 is a graph of different release profiles of matrices of different shapes from FIG20 according to the present technology; FIG22 shows the concentration distribution of volatiles in a spherical carrier according to the present technology; and 23 is a graph of different release profiles from the spherical carrier of FIG. 22 into a container in accordance with the present technology. DETAILED DESCRIPTION

[0007] While illustrative embodiments have been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention.

[0008] Before explaining in detail at least one embodiment of the inventive concept disclosed and / or protected by the claims, it should be understood that the inventive concept disclosed and / or protected by the claims is not limited in its application to the details of the construction and arrangement of the components or steps or methods set forth in the following description. The inventive concept disclosed and / or protected by the claims is capable of other embodiments or can be practiced or implemented in various ways. Moreover, it should be understood that the words and terms used herein are for descriptive purposes and should not be considered limiting.

[0009] Unless otherwise defined herein, technical terms used in conjunction with the inventive concepts disclosed and / or protected by the claims shall have the meanings commonly understood by those of ordinary skill in the art. In addition, unless the context otherwise requires, singular terms shall include plural terms, and plural terms shall include the singular.

[0010] All patents, published patent applications, and non-patent publications mentioned in this specification are indicative of the technical level of those skilled in the art to which the inventive concepts disclosed and / or claimed herein pertain. All patents, published patent applications, and non-patent publications cited in any part of this application are expressly incorporated herein by reference in their entirety, to the same extent as if each individual patent or publication was specifically and individually indicated to be incorporated by reference.

[0011] In light of the present disclosure, all articles and / or methods disclosed herein can be made and executed without undue experimentation. Although the articles and methods of the inventive concepts disclosed and / or protected by the claims have been described according to preferred embodiments, it is obvious to those skilled in the art that the steps or step sequences of these articles and / or methods and the methods described herein can be changed without departing from the concept, essence and scope of the inventive concepts disclosed and / or protected by the claims.

[0012] As used in accordance with the present disclosure, the following terms shall be understood to have the following meanings, unless otherwise indicated.

[0013] When used with the term "comprising", the words "a" or "an" may mean "one", but are also consistent with the meanings of "one or more", "at least one", and "one or more than one". The use of the term "or" is used to mean "and / or", unless it is explicitly indicated that the alternative is only referred to when the alternatives are mutually exclusive, although the present disclosure supports a definition that only refers to the alternative "and / or". Throughout this application, the term "about" is used to indicate that the value includes the inherent error variation of the quantitative device, the method for determining the value, or the variation that exists among the research subjects. For example, but not by way of limitation, when the term "about" is used, the specified value may vary by plus or minus 12%, or 11%, or 10%, or 9%, or 8%, or 7%, or 6%, or 5%, or 4%, or 3%, or 2%, or 1%. The use of the term "at least one" will be understood to include any number of one and more than one, including but not limited to 2, 3, 4, 5, 10, 15, 20, 30, 40, 50, 100, etc. The term "at least one" can extend to 100 or 1000 or more depending on the term attached to it; in addition, the number 100 / 1000 is not considered limiting, as lower or higher limits may also produce satisfactory results. In addition, the use of the term "at least one of X, Y, and Z" will be understood to include X alone, Y alone, and Z alone, as well as any combination of X, Y, and Z. For example, the use of ordinal terms (i.e., "first," "second," "third," "fourth," etc.) is only for the purpose of distinguishing two or more items, and is not meant to imply any order or sequence or importance of one item relative to another or any order of addition.

[0014] As used herein, the words "comprise", "have", "include" or "contain" are inclusive or open-ended, and do not exclude additional unlisted elements or method steps. As used herein, the term "or a combination thereof" refers to all permutations and combinations of the listed items preceding the term. For example, "A, B, C or a combination thereof" is intended to include at least one of the following: A, B, C, AB, AC, BC or ABC, and if the order is important in a particular context, also includes BA, CA, CB, CBA, BCA, ACB, BAC or CAB. Continuing with this example, combinations containing repetitions of one or more items or terms are explicitly included, such as BB, AAA, AB, BBC, AAABCCCC, CBBAAA, CABABB, etc. The skilled person will understand that there is generally no limit to the number of items or terms in any combination, unless it is obvious from the context.

[0015] Postharvest corruption of fruits, vegetables and plants can cause significant economic losses. Certain volatile essential oil compounds (also referred to as "bioactive compounds," "compounds," or "preparations") have bioactive properties that help protect perishable agricultural products from corruption. When these bioactive compounds are released into an environment where perishable agricultural products are stored, postharvest losses due to corruption can be reduced. Preparations can include one or more such active compounds that inhibit corruption by limiting microbial growth. Preparations can also include compounds with other important functions, such as those that preserve and stabilize active compounds (such as antioxidants), compounds that help produce desired aroma characteristics, those compounds that can regulate ethylene responses, and compounds that stimulate and regulate the natural defense / immune response of agricultural products. Finally, such ingredients can also be combined with various carriers and controlled release matrices such as waxes. These preparations or composite preparation-carrier combinations constitute platforms that perform core functions that affect biological responses.

[0016] The technology of the present invention generally relates to a delivery system by which a composition having one or more active compounds is delivered to the environment to reduce the decomposition of perishable items. Specifically, one or more delivery systems comprising a composition having one or more active compounds, a carrier, and a release rate-changing mechanism allow the one or more active compounds to be released into the surrounding environment in a controlled, predictable manner.

[0017] One method of introducing active compounds into the environment is by means of electromechanical-thermal-fluid devices that can precisely dispense the compound from a supply reservoir using a variety of delivery, spraying, atomization / misting / vaporization or similar techniques.

[0018] Another approach is to design the material composition containing one or more active compounds so that the delivery system has an overall property of releasing the active compound in a slow, predictable manner. For example, mixing one or more active compounds in a diffusion retarding matrix can moderate their rate of release. For example, a volatile compound dispersed in a matrix with a lower diffusion rate will be released more slowly than a volatile compound dispersed in a matrix with a higher diffusion rate. An example of one or more active compounds dispersed in a diffusion retarding matrix is ​​one or more essential oils with the active compound mixed in a wax carrier.

[0019] In some embodiments, the delivery system includes one or more compositions, one or more carriers, and one or more release rate changing mechanisms. In some embodiments, the one or more compositions contain one or more active compounds. In one embodiment, the one or more compositions have one or more active compounds and one or more inactive compounds. The release rate changing mechanism can be one or more diffusion barriers, the form of the carrier, the structure of the composition, etc. The release rate changing mechanism can affect the release rate of one or more compounds to the surrounding environment in a controlled, predictable manner.

[0020] The one or more active compounds of the composition may comprise or consist of a volatile compound, one or more plant immunostimulatory compounds, one or more non-volatile compounds and one or more ethylene-acting agent compounds or a combination thereof. The one or more volatile compounds that can be used in the embodiments disclosed herein may include, but are not limited to, trans-2-hexenal, trans-2-octenal, trans-2-nonenal, trans-2-decenal, trans-2-dodecenal, p-isopropylbenzaldehyde, citronellal, thymol, perillaldehyde, carvacrol, citral, carvone, menthol, borneol acetate, 1-octanol, terpinen-4-ol, linalool, trans-anethole, trans-cinnamaldehyde, ethyl octanoate, ethyl nonanoate, ethyl decanoate, methyl octanoate, methyl nonanoate, methyl decanoate, fenchol, borneol, camphor, methyl eugenol, menthol, methyl salicylate, methyl anthranilate, phenylethyl acetate, phenylacetic acid, cinnamic acetate, γ-octalactone, γ-decanoic acid, eucalyptol, geranium oil, lavender oil, thyme oil, clove oil, (-)-Bornyl acetate, (-)-terpinen-4-ol, (+)-carvone, (±)-citronellal, (R)-(+)-citronellal, (S)-(–)-citronellal, (R)-(+)-longifolia mint, thymol, 4-isopropylbenzaldehyde (cuminaldehyde), 4-allylanisole, cis-3,7-dimethyl-2,6-octadien-l-ol, citronellol, trans-cinnamic acid Methyl ester, myrcene, ocimene, terpineol, 1-methyl-3-methoxy-4-isopropylbenzene, menthol, menthone, isomenthone, vanillin, geranyl formate, palmitic acid, (S)-(-)-perillaldehyde, nootkatone, hinokitiol, d-limonene, s-limonene, -isopropyltoluene, nerolidol, 3-decen-2-one and other stereoisomers of these compounds and combinations thereof. In some embodiments, the carrier material is selected from the group consisting of water, paraffin, petroleum wax, natural wax, beeswax, resin, synthetic polymer, biodegradable natural polymer, ceramic, modified cellulose, methyl cellulose, surfactant, mesoporous silica nanoparticles, microporous alumina, anodized aluminum, activated carbon, zeolite, metal carboxylates, inorganic compounds and combinations thereof.

[0021] In some embodiments, one or more compositions comprise one or more odor compounds configured to counteract or neutralize the odor of one or more biologically active compounds. In some embodiments, the one or more odor compounds are one or more furanones (such as strawberry furanone, maple furanone, or caramel furanone), methyl cinnamate, methyl butyrate, propyl heptanoate, hexyl cinnamate, methyl anthranilate, methyl jasmonate, nonadienal, or a combination of odor compounds.

[0022] It will be understood by those of ordinary skill in the art that essential oils refer to oils distilled or extracted from plants. Essential oils are not necessarily true oils like lubricant vegetable oils, but have high fluidity and very high volatility. Essential oils can be complex mixtures of different organic molecules (also referred to as essential oil components or EOCs), monoterpenes, diterpenes, sesquiterpenes or their oxidized forms, terpenes, alcohols, esters, aldehydes, ketones, phenols, thiols, isothiocyanates, and alkaloids (including but not limited to capsaicinoids). Synthetic oils are usually made from one or more ingredients that dominate a particular essential oil. For example, menthol usually replaces mint, and cineole replaces eucalyptus. In addition, the chemical composition of essential oils can vary depending on the time of day, month or season when the essential oils are harvested, the environmental conditions leading to and including the harvest of the essential oils, the means for extracting the essential oils, and for synthetic oils, the chemical composition can vary from batch to batch. Environmental conditions leading to and including the harvest of essential oils include but are not limited to drought, excessive precipitation, etc.

[0023] Both synthetic and naturally occurring essential oils can be used for aroma, medicine, preservation, solvent and insecticide purposes. For example, essential oils such as methyl salicylate or thymol are impregnated into water-insoluble resins, and they can be used to distribute aroma or medicinal vapors into a room. Typical essential oils are derived from thyme, lemongrass, citrus, anise, cloves, fennel seeds, roses, lavender, citronella, eucalyptus, peppermint, camphor, sandalwood, cinnamon, cedar, almonds, grapes, walnuts, jojoba trees, olives, etc. In some embodiments, essential oils can also be derived from nuts or seeds. Essential oils are generally liquid at room temperature (20° C. to 25° C.). Essential oils suitable for the present disclosure are typically commercially available and preferably refined. One or more essential oil components may be present in each essential oil.

[0024] The one or more plant immunostimulatory compounds may include, but are not limited to, pinene, camphene, terpinene, terpineol, chitosan, methyl jasmonate, and methyl salicylic acid, ethyl salicylic acid, methyl cinnamic acid, β-aminobutyric acid, fructan (inulin, fructan), ethylene, hypersensitive protein, jasmonic acid, etc. The one or more plant immunostimulatory compounds refer to compounds that neither directly affect pathogenic organisms nor change the DNA of the treated perishable items, but activate the natural defense mechanism in the perishable items. It should be understood by those of ordinary skill in the art that plant immunostimulatory compounds may also be referred to as plant activators.

[0025] Examples of one or more non-volatile compounds may include, but are not limited to, curcumin, chitosan, phytoalexins, phytoanticipins, one or more preservatives, and one or more antioxidants, including, but not limited to, vitamin E, vitamin A, vitamin C, beta-carotene, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), or UV protectants such as titanium dioxide. One or more non-volatile compounds may have a microbicidal effect, an immunostimulatory effect, and / or may prevent or slow down the oxidation process in perishables. The microbicidal effect may reduce the infectivity of microorganisms such as bacteria or fungi that may have a spoilage effect on perishables. In one embodiment, a composition comprising a protective coating, one or more volatile compounds, and one or more non-volatile compounds may produce a synergistic effect that further reduces the loss of perishables compared to the loss of perishables of the individual components. In another embodiment, a lower concentration of one or more volatile compounds and one or more non-volatile compounds in a composition having a protective coating may achieve a desired biological result more quickly than a higher concentration of one or more volatile compounds and one or more non-volatile compounds that are not in a composition having a protective coating. In another embodiment, the addition of one or more antioxidants and / or one or more preservatives to the delivery system can help maintain the efficacy of the biologically active agent of the composition.

[0026] One or more ethylene-acting agent compounds that can be used in the inventive concepts disclosed and claimed herein may include, but are not limited to, norbornadiene, resveratrol, sodium permanganate, potassium permanganate, vanillin, activated carbon, and 1-methylcyclopropene. One or more ethylene-acting agent compounds refer to ethylene absorbing / adsorbing or degrading compounds and compounds that remove free ethylene from the environment, reduce its production, or reduce sensitivity to ethylene in perishable items. An example of a volatile ethylene antagonist is 1-methylcyclopropene (1-MCP). 1-MCP binds to multiple ethylene receptors of agricultural products and blocks the recognition of ethylene by multiple ethylene receptors. Blocking of ethylene recognition by multiple ethylene receptors of perishable items tends to reduce the effectiveness of ethylene in triggering the ripening reaction of perishable items. Blocking of multiple ethylene receptors of perishable items also reduces the autocatalytic production of ethylene. 1-MCP can reduce ethylene production and make perishable items insensitive to ethylene. In addition, the ethylene-acting agent compound can be an ethylene absorber, such as activated carbon, or an ethylene degrader, such as potassium permanganate.

[0027] In some embodiments, one or more delivery systems include one or more compositions with one or more active compounds and carriers. The carrier may be in a solid, semi-solid, liquid or gaseous state. The carrier may act as a medium and / or diffusion retardant to stabilize / maintain one or more active compounds, thereby regulating the release rate of one or more active compounds from the carrier to the environment. The carrier may be selected from the group consisting of water, paraffin, petroleum-derived wax, beeswax, plant-derived wax, resin, synthetic polymer, biodegradable natural polymer, oil and fat, ceramic compound, one or more inorganic compounds, macrocyclic compounds such as cyclodextrin, surfactant, clay, fiber, fibrous material, paper and metal organic framework (MOF). Macrocyclic compounds include cyclodextrin and other similar compounds with cage-like structures. Biodegradable natural polymers may be derived from natural plants or animal materials, ceramics or inorganic compounds. In some embodiments, the carrier can be made of paraffin, wax, natural rubber, synthetic rubber, shellac, modified cellulose, cellulose composites, semipermeable plastics (including but not limited to polyisoprene, polybutadiene, nylon (polyamide), polyurethane, low density polyethylene (LPDE), high density polyethylene (HDPE), polyethylene terephthalate (PET), polystyrene (PS), polylactic acid (PLA), polycarbonate (PC), polypropylene (PP), polycaprolactone (PCL), polyvinyl alcohol (PVA), ethylene-vinyl alcohol (EVOH), polyvinyl acetate (PVAc), polyacrylic acid (PAA), polyethylene oxide (PEG), perforated plastic films, perforated or patterned metallized plastic films (wherein the non-metallized portions are permeable to the active compound)), sponges, porous materials, and combinations, mixtures, blends, or composites thereof. In some embodiments, the semipermeable plastic can take many different forms, including films, particles, pellets, and the like.

[0028] In some embodiments, the carrier can take many different structures. In some embodiments, the structure can be a wax, crystal, resin or oil gel structure. For example, if the carrier is a wax or oil structure, the carrier can be made of animal wax (a natural mixture of wax esters and sterol esters, such as beeswax or lanolin), plant wax (alkanes, wax esters, fatty acids, fatty alcohols, plant sterols such as carnauba wax, candelilla wax, bayberry wax, and a natural mixture of soybean wax), natural / vegetable oils (natural triglycerides or processed natural triglycerides such as rapeseed oil, grape seed oil, avocado oil, walnut oil, coconut oil, soybean oil, palm oil, and a mixture of hydrogenated oils), petroleum and wax (alkanes such as paraffin oil, paraffin, and a mixture of microcrystalline wax) and their combinations. In some embodiments, when the carrier is a crystalline structure, the carrier can be made of fatty acids (lauric acid, palmitic acid, stearic acid, oleic acid, etc.), fatty acid salts (sodium palmitate, potassium palmitate, sodium stearate, calcium stearate, etc.), fatty alcohols (cetyl alcohol, cetearyl alcohol, etc.) and their combinations. In a resin structure, the carrier may be formed from natural resins or rosins, modified resins, resin acid mixtures such as pine resins or rosins, mastic rosins and dammar rosins, hydrogenated pine rosins, glycerol esters of pine rosins, and mixtures thereof. In the example where the carrier is in an oleogel structure, the carrier may include a combination of waxes and / or oils and / or crystals and / or resins that form a solid, gel, cream, or viscous liquid. In some embodiments, the proportions of the components will adjust the mechanical properties of the carrier.

[0029] In some embodiments, the carrier may have a hydrogel or gum structure, a plastic structure, or a porous solid structure. In a hydrogel or gum structure, the carrier may include collagen / gelatin, silk, gluten, zein, casein, keratin (such as wool), soy protein, pea protein, sunflower protein, polysaccharides such as cellulose, modified cellulose (such as methylcellulose, ethylcellulose, hydroxypropyl methylcellulose, etc.), pectin, chitosan, chitin, alginate, starch, carrageenan, agar, shellac, hyaluronic acid, gums (including xanthan gum, gum arabic, guar gum, locust bean gum, mastic, gellan gum, spruce gum, and combinations thereof). In some embodiments, the plastic structure may include natural rubber, synthetic rubber, semi-permeable plastic (including but not limited to polyisoprene, polybutadiene, nylon (polyamide), polyurethane, low-density polyethylene (LPDE), high-density polyethylene (HDPE), perforated plastic film, polyethylene terephthalate (PET), polystyrene (PS), polylactic acid (PLA), polycarbonate (PC), polypropylene (PP), polycaprolactone (PCL), polyvinyl alcohol (PVA), ethylene-vinyl alcohol (EVOH), polyvinyl acetate (PVAc), polyacrylic acid (PAA), polyethylene oxide (PEO), perforated or patterned metallized plastic film (wherein the non-metallized portion is permeable to the active compound)), sponge, porous material, and combinations thereof.

[0030] In porous solid structures, the support may include activated carbon, porous oxides (silica, alumina, titania), porous concrete mixtures, zeolites, clays such as bentonite and montmorillonite, paper, cellulose sponges, felts such as cellulose felt, cork, glass fiber paper, sponges such as PP sponges and PE sponges, and combinations thereof.

[0031] In some embodiments, the carrier includes a solvent or diluent, such as ethanol, glycerol, water, saline solution, such as sodium chloride, potassium chloride, calcium chloride, magnesium chloride, calcium carbonate, and mixtures thereof. In some embodiments, the carrier includes an emulsifier or wetting agent. In some embodiments, the emulsifier or wetting agent is selected from fatty acids (lauric acid, palmitic acid, stearic acid, oleic acid, etc.), fatty acid salts (sodium palmitate, potassium palmitate, sodium stearate, calcium stearate, etc.), fatty alcohols (cetyl alcohol, cetearyl alcohol, etc.), monoglycerides (monostearic acid glyceryl, monopalmitin, etc.), diglycerides (glyceryl distearate, glyceryl dipalmitate, etc.), lecithin / phospholipids (egg yolk lecithin, soybean lecithin or sunflower lecithin), sterols (vegetable Sterols, cholesterol, etc.), sorbitans (sorbitan laurate, sorbitan stearate, etc.), polysorbates (polyoxyethylene sorbitan laurate, polyoxyethylene sorbitan stearate, etc.), polyethylene ethers (polyethylene lauryl ether, polyethylene cetyl ether, etc.), sulfate surfactants (sodium octyl sulfate, sodium dodecyl sulfate, etc.), quaternary ammonium surfactants (cetyl trimethyl ammonium chloride, behenyl trimethyl ammonium chloride), and combinations thereof.

[0032] In some embodiments, one or more active compounds of the composition are released from the carrier into the environment by two mechanisms. In one mechanism, when the chemical structure of one or more compounds constituting the carrier is changed, the one or more active compounds can be released into the environment by diffusion from the carrier of the delivery system.

[0033] Changing the chemical structure of one or more compounds of the carrier may include, but is not limited to, the degree of cross-linking present in the structure of the chemical structure of the one or more compounds, the ratio of hydrophobic regions to hydrophilic regions of the compounds constituting the carrier, manipulating the degree of charge of the chemical structure of the one or more compounds, and changing the ratio of low molecular weight components to high molecular weight components of the one or more compounds constituting the carrier. Changes to the chemical structure of the one or more compounds of the carrier may result in different diffusion rates of the active compound through the carrier. Changes to the chemical structure of the one or more compounds of the carrier may also change the physical state of the carrier from a semi-solid state to a solid state. Typically, when the carrier is in a semi-solid state, the carrier has a lower density and a higher permeability to the active compound. In contrast, when the carrier is in a solid state, the carrier has a higher density and a lower diffusion (also known as permeability or release rate).

[0034] FIG. 1A shows an example compound according to the present technology. As shown in FIG. 1A , by way of example, when the polymer backbone branching structure of the compound of the carrier is changed, the physical properties may be significantly affected. For example, low-density polyethylene (LDPE) and high-density polyethylene (HDPE). The monomer building blocks are both composed of ethylene, but the resulting LDPE and HDPE have different branching structures. HDPE is mainly made of linear chains and is tightly packed in the carrier. This stacking of HDPE allows the carrier to have a higher density and a higher crystallinity. In contrast, LDPE has a high degree of branching and its stacking in the carrier is not too tight. The stacking of LDPE allows the carrier to have a lower density and a lower crystallinity. When the carrier contains HDPE and / or LDPE, the underlying structural features are the cause of the significant differences in mechanical and transport properties (including the release rate of one or more active compounds from the carrier to the environment) between the HDPE and LDPE of the carrier.

[0035] FIG. 1B is a graph of properties of example compounds of FIG. 1A according to the present technology. On the horizontal axis is water vapor transmission rate. On the vertical axis is oxygen transmission rate. The shaded area represents the optimal oxygen transmission rate. Various compounds are shown on the graph, including biaxially oriented polypropylene (BOPP), polyvinylidene chloride (PVDC), polyethylene terephthalate (PET), ethylene vinyl alcohol (EVOH), nylon, and polystyrene (PS). LDPE and HDPE as shown in FIG. 1A are also plotted and circled for emphasis.

[0036] 2A to 2I are example carriers 100 according to the present technology. In some embodiments, the carrier 100 can be a single substance, made of a blend of multiple substances, with a homogeneous microstructure (such as wax) or with a heterogeneous structure, such as a porous substrate. In some embodiments, the carrier 100 may include substances with different compounds. In some embodiments, the carrier 100 may be shaped into beads or spheres, spheroids, ovoids, lumps, small pancake-like shapes, short sticks / cylindrical shapes, unevenly shaped particles, planar films, thick planar layers, thick layers with patterned surfaces (such as honeycomb shapes), powders dispersed in another matrix (e.g., fine powders or small particles containing active compounds mixed into wax or paraffin as inclusion compounds, wherein the resulting wax with inclusion compounds is shaped into physical embodiments as described herein). In some embodiments, one or more biologically active compounds or second particles 110B are dispersed in the carrier body material 101. In some embodiments, the particles 110A, 110B may be dispersed as particles 110A, 110B of only one or more biologically active compounds, inclusions containing particles 110A, 110B (such as inclusions 105 in FIG. 2B ), or compounds uniformly mixed with the carrier bulk material 101. In the latter case, there may be no distinguishably identifiable particles (e.g., drops) of compound 110 within 100, but a mixture of 101 and 110 may be within inclusions 105. As described herein, inclusions 105 may be any substance added to the carrier 100 or the carrier bulk material 101. In some embodiments, inclusions 105 may be particles, vesicles, beads, flakes, fibers, solid drops, gel-like drops, or liquids of any shape or size. In the case of a patterned surface, the size scales of discrete particles, the thickness of one or more layers, and the spacing and depth size scales of the pattern may span a range or length scale from 1 micron to 10 centimeters. The pattern can be largely regular, such as but not limited to a honeycomb structure or a regular array of indentations, or irregular, such as but not limited to a plurality of pits of different sizes or irregular indentations on the surface. The materials of the overall geometry and topology described herein may have further underlying structures, such as the porosity of the bulk material. They may also have hierarchical structures of geometry and topology that contain each other. For example, a carrier material 101 or another carrier material different from the bulk material forming the carrier 100 may be made into small inclusions 105 of a specific size range (and it may be loaded with some bioactive compounds 110), as shown in FIG2B . These particles may be porous or non-porous. These inclusions 105 may then be dispersed in a layer of another carrier 100 that is thicker than the size scale of the inclusions 105, such as a wax layer that may also contain active compounds.This material made of inclusion complexes 105 can be dispersed in a continuous homogeneous or porous carrier matrix (bulk material 101), which can be formed into a plate and whose surface can be patterned to have a honeycomb structure with a certain spacing and depth or a range of such spacing and depth values ​​to make a carrier 100, as shown in Figure 2A. Finally, the biologically active compound 110 can be uniformly or non-uniformly distributed in the inclusion complexes 105, or uniformly or non-uniformly distributed in the carrier material 101. In some embodiments, the bulk carrier material 101 is the main material made of the carrier, such as wax, porous paper, etc., even though it may have additional compounds, particles or inclusion complexes. The bulk material itself can be homogeneous, such as wax, or porous, such as paper, or it can have other microstructures inside.

[0037] One or more diffusion barriers (or layers) 115 may be applied to the composition / carrier 100 to slow down the overall release rate of one or more active compounds 110 into the environment adjacent to perishable items, as shown in FIG. 2C . In some embodiments, the one or more diffusion barriers 115 are laminated diffusion barriers. In some embodiments, the one or more diffusion barriers 115 are physically separated one or more layers, such as a film or diaphragm that can form a capsule or bag. In the case of a bag, the function of the one or more diffusion barriers 115 is not necessarily a "diffusion barrier", but a physical closure that is sufficiently permeable to the active compound 110 so that the loose material inside the bag containing the compound 110 remains inside.

[0038] In some embodiments, one or more active compounds 110 are dispersed in the carrier bulk material 101. In some embodiments, the one or more active compounds 110 may be dispersed as particles of only one or more biologically active compounds 110 (as shown in FIG. 2C ), inclusions in other particles containing particles of one or more active compounds 110A, 110B (such as inclusions in inclusions 105 in FIG. 2B ), or one or more active compounds 110 uniformly mixed in the carrier bulk material 101. In the latter case, there may be no distinguishably identifiable particles (e.g., drops) of compound 110 within 100, but a mixture of bulk carrier material 101 and one or more active compounds 110 may be within inclusions (particles) 105. The permeability of the one or more diffusion layers 115 may be affected by the material contained in the one or more diffusion barriers 115 and / or the thickness of the one or more diffusion barriers 115. In one embodiment, the permeability of the diffusion barriers 115 may change in response to changes in temperature and humidity. In some embodiments, any and all layers as described herein may change in response to triggers such as temperature and / or humidity. Similarly, oil droplets with one or more active compounds 110 can be suspended in an environment-dependent carrier 100, such as a polymer matrix. For example, in another embodiment, one or more diffusion barriers 115 can be positioned adjacent to one or more carriers 100 containing one or more compositions with active compounds 110 to alter the release rate of the composition into the environment of the perishable item. In another embodiment, one or more diffusion barriers 115 can have a second composition or a third composition containing one or more active compounds. One or more diffusion barriers with a second composition or a third composition containing one or more active compounds can slow the release rate of the one or more active compounds and / or the second active compound or the third active compound into the environment adjacent to the perishable item.

[0039] In some embodiments, the carrier 100 includes particles of a first size 110A, particles of a second size 110B, and a diffusion barrier 115, as shown in FIG2D. In some embodiments, the size of each particle changes the surface to volume ratio of each type of active compound, which changes the release rate of the one or more active compounds 110A, 110B. In some embodiments, the first particle 110A and the second particle 110B contain the same active compound, but in other embodiments, the first particle 110A contains the first active compound and the second particle 110B contains the second active compound. All other materials within the carrier (or bag) are the same (including the one or more active compounds), the smaller second size particles 110B will release the payload of the one or more active compounds 110B on a faster time scale, and the larger first size particles 110A will have a slower (or longer) time scale. The net effect will be a combination of shorter and longer time scales.

[0040] In some embodiments, the carrier 100 includes one or more layers, as shown in FIG. 2E. In some embodiments, the particle of FIG. 2E may be one of a plurality of particles embedded in the carrier 100 or otherwise dispersed in the carrier. In some embodiments, the carrier particle 100 includes one or more active compounds 110, a diffusion barrier 115, and a triggered release layer 125. In some embodiments, the diffusion barrier 115 regulates the release of the one or more active compounds 110. In some embodiments, the triggered release layer 125 triggers the release of the one or more active compounds 110 when it interacts with moisture, water, a specific temperature, etc. In some embodiments, the triggered release layer 125 is an impermeable barrier that triggers the release of the one or more active compounds 110 when it is physically removed (such as peeling it off). In this embodiment, the impermeable triggered release layer 125 may include an additional layer that helps it adhere to an adjacent layer, such as a thin layer of adhesive.

[0041] In some cases, the bioactive compound 110 to be released may form a weak reversible covalent bond with a compound constituting the carrier bulk material 101, a compound present in or added to the carrier bulk material 101, or some other compound included in any part of the carrier 100. This includes any component or other layer that may be included in the carrier 100 shown in FIG. 2E. In this way, the carrier 100 can be used as a storage capacitor for the active compound 110, wherein the active compound 110 is covalently attached so that they are less mobile and less volatile. By selecting the chemical type involved in attaching the bioactive substance 110, the reverse reaction that breaks these covalent bonds (and thereby releases the bioactive substance to be released) can be fine-tuned. An example of such a system is based on weak covalent bonds present in a large number of compounds, characterized by the presence of double bonds connecting carbon and nitrogen atoms, called "Schiff bases". Schiff bases can be prepared by forming chemical bonds between primary amines and aldehyde or ketone functional groups. Another example of such a system is based on covalent bonds present in a large number of compounds, characterized by the presence of chemical bonds connecting carbon and oxygen atoms, called "esters". Esters can be prepared by forming a chemical bond between an alcohol and a carboxylic acid that fixes a volatile compound, which may have any of these parts that participate in the esterification reaction. When interacting with water, the ester bond can hydrolyze and release one or both of the compounds that form the ester bond. In some cases, the covalent bonds formed when the active compound combines with other compounds to form a Schiff base or an ester can respond to various environmental stimuli. For example, the rate of breaking the covalent bond can increase with humidity, acidity, alkalinity, temperature, or exposure. This allows the design of a "smart delivery system" that responds to conditions in a desired manner. For example, in the case of Schiff bases and esters, under the action of an "activator", the hydrolysis rate will cause these covalent bonds to break, thereby releasing the active compound, making it more mobile and volatile. The activator may include moisture, acid, base, or some combination of these. The acid activator compound may be acetic acid, citric acid, ascorbic acid, or any other acid or combination thereof. The alkaline activator compound may be sodium carbonate, sodium bicarbonate, or any other base or combination thereof. In some embodiments, such covalently bound active compounds can be placed near an acid activator or a base activator in a manner that they cannot initially react with each other. For example, they can be placed in different compartments physically separated from each other, such as in a multi-compartment blister pack or a glow stick. The separator can be mechanically broken to allow compound mixing and covalent bond hydrolysis. This action can be used to activate the system and begin to release the active compound according to the needs of the user or during manufacturing. In another embodiment, the active compound and the activator can be dispersed in a continuous matrix (bulk material 101) as discrete solid particles or liquid or gel drops that are kept physically out of contact with each other. In some embodiments, the activator particles dispersed in the bulk material 101 can be solid particles of citric acid or any other acid. In some embodiments, these solid particles are crystals.When moisture enters the use environment, the activator can begin to dissolve in the matrix and diffuse through the matrix to reach the covalent bond and hydrolyze it, thereby releasing the biologically active compound. In the presence of fresh agricultural products, the humidity required for activation can be passively from the use environment, or as needed, such as spraying or spraying water on the embodiment to activate it. This can be done by the user, or in the packaging step during manufacturing. In another embodiment, an active compound covalently bound to another compound to form an ester or Schiff base is included, and there is no activator near it. An activator (such as a citric acid solution) is sprayed or sprayed onto the embodiment by the user or during manufacturing to activate it and begin to release the biologically active compound.

[0042] In another embodiment, the release rate change mechanism may be based on the structure of the composition and the form of the carrier 100. The structure of the composition may include macroscopic, mesoscopic and microscopic geometries, such as beads or inclusions 105 of various sizes; small particles with specified sizes and aspect ratios; honeycomb structures (as shown in Figure 2A), and other multilayer configurations of the composition. For example, the form of the carrier 100 and any of its components may also include different amounts of porosity. The macroscopic, mesoscopic and microscopic geometries of the structure of the composition and the form of the carrier 100 may affect the transfer and release rate of the composition into the environment of perishable items. In one embodiment, the amount of one or more active compounds 110 in the composition and the structure of the composition affect the release rate of the composition into the environment of one or more perishable items. In another embodiment, based on the structure of the composition and the form of the carrier 100, the release rate of one or more active compounds 110 may be affected by the ratio of the amount of active compound 110 in the composition to the volume of the composition. For example, the porosity of the carrier 100 may affect the delivery of the composition in the delivery system. In another embodiment, the structure of the composition and / or the form of the carrier 100 may be combined in a delivery system to achieve a highly complex release profile. For example, a delivery system comprising one or more compositions having one or more active ingredients 110 and one or more carriers 100 formed into one or more shapes is suitable for releasing the composition into the environment of a perishable item at a fast release rate, while a delivery system comprising one or more compositions having one or more carriers 100 formed into one or more shapes can release the composition 110 into the environment of a perishable item at a slower release rate.

[0043] In one embodiment, the form of the carrier 100 may be porous. Examples of porous carriers include, but are not limited to, mesoporous silica, anodized aluminum, sponges, foams, cellulose matrices (such as paper or cardboard), and various polymers, etc. The porosity, pore size distribution, tortuosity of the porous carrier 100 and the transport characteristics of one or more compositions of the delivery system may be different. In one embodiment, one or more compositions 110 may be positioned in one or more holes of the porous structure. These holes may be microscopic and may be present in the entire component of the carrier 100, so they are not shown for simplicity. Specifically, unlike only surface patterns, one or more holes may be located in the carrier bulk material 101. Those skilled in the art will appreciate that in some embodiments, one or more holes are similar to holes in a sponge, or similar to holes (microscopic physical gaps) in a compacted cellulose (paper-like) sheet. In some embodiments, the porous material (i.e., the bulk carrier material 101) may be further patterned to form the surface topology 120 in FIG. 2B. By way of example, but not limitation, one or more compositions 110 combined with a carrier 100 comprising beeswax may be positioned within one or more pores of a carrier 100 comprising a mesoporous material, or within a cavity of a surface pattern 120. In some embodiments, the one or more compositions that fill the pores in 100 or pattern 120 may be selected from one or more essential oils or blends of essential oils, one or more liquid compositions comprising an active compound and a liquid solvent (such as an oil in a liquid carrier, or a liquid emulsion of vesicles as described herein), a gel or other wax composition comprising an active compound and other carriers, or other solid compositions with active compounds that can be impregnated into the pores while in a liquid state. In some embodiments, the solid composition is liquid at elevated temperatures, or is liquid in a solution made of a highly volatile solvent such as ethanol, wherein, after filling the pores, the solvent evaporates, leaving a dry composition in the pores of the carrier 100 or in the surface pattern 120.

[0044] In another embodiment, the microscopic morphology of any part of the carrier material 101 or carrier 100 can be microporous. One or more active compounds are released into the environment via the microporous structure ("pores") of the carrier or through the cavity defined by the surface pattern 120. The pore or cavity has a space without any material, or may contain one or more other materials, including one or more active compounds in any physical state. In one embodiment, the pore or cavity 120 can be single; that is, one pore is surrounded from all sides by the carrier 100. In another embodiment, the pore or cavity 120 can be two or more; that is, two or more pores can be surrounded by the carrier 100. In another embodiment, the network of pores can be physically connected, thereby providing one or more pore passages positioned within the carrier 100. In one embodiment, one or more pore passages can be positioned adjacent to the environment surrounding the perishable item. Examples of carriers 100 having a microporous structure include, but are not limited to, mesoporous silica nanoparticles, microporous alumina, and anodized aluminum with an anodized layer. Mesoporous silica nanoparticles have unique properties, such as ordered pore arrangement, biocompatibility, and can be used as a controlled release mechanism. Mesoporous silica nanoparticles can be incorporated into other matrices such as packaging and wax to further affect the controlled release characteristics. The characteristics of the pores or surface cavities 120 in these materials can be controlled to obtain the desired controlled release characteristics. One or more surfaces of the mesoporous silica particle carrier and the microporous alumina carrier can also be chemically modified to change hydrophilicity, hydrophobicity, or directly retain the compound by chemically attaching cyclodextrin to the compound. In one embodiment, the carrier can be modified by a molecular nanoimprinting process. The molecular nanoimprinting process uses a molecular imprinting resin, and the compound solidifies at the same time so that the surface cavity defined by the pattern 120 of the carrier 100 has molecular specificity.

[0045] In another embodiment, the structure of the composition may have a particle configuration of powder, granules, etc. (such as inclusion compound 105), as shown in FIG. 2B. Multiple particle configurations can be changed into desired macroscopic shapes, such as sheets, balls, disks, etc. In one embodiment, the microstructure of the macroscopic shape can be optimized to achieve a certain level of porosity between powders / granules. The macroscopic shape can be further optimized to achieve different surface to volume ratios. The process of forming the macroscopic shape determines the surface to volume ratio of a single particle configuration and the macroscopic shape of multiple particle configurations. In another embodiment, multiple particle configurations can also be formed into a macroscopic shape with one or more holes or various surface patterns 120.

[0046] In some embodiments, such as shown in FIG. 2F, one or more holes or surface cavities 120 of the macro-shaped carrier 100 may be impregnated or backfilled with a substance 115 (such as a resin, a hydrogel, a viscous liquid, etc.). The substance 115 may be used as a barrier (such as a diffusion barrier described herein) that affects the release rate of one or more active compounds 110 from one or more patterned cavities 120 of the macro-shaped carrier 100. In another embodiment, one or more patterns 120 may be inert and used as a scaffold, as shown in FIG. 2B. One or more patterns used as a scaffold may have a diffusion-blocking matrix positioned within the one or more patterns. In one embodiment, one or more compositions may be a plurality of bead particle configurations of different sizes. A plurality of bead particle configurations with smaller sizes have a higher surface-to-volume ratio. A plurality of bead particle configurations with smaller sizes will have a faster release rate to release one or more active compounds to achieve a target gas concentration. A plurality of bead particle configurations with smaller sizes will dispense one or more compositions at a faster rate. A plurality of bead particle configurations with larger sizes (and therefore a smaller surface-to-volume ratio) may maintain a target concentration for a longer period of time. In another embodiment, a plurality of bead particle configurations may be coated with one or more diffusion barriers. One or more diffusion barriers may slow the release rate. In some embodiments, the diameter size of the plurality of beads may be in the range of 1 micron to 1 centimeter. It should be understood that when the carrier is an irregularly shaped particle, the diameter is the diameter of a sphere of similar size. In some embodiments, the thickness of the carrier may be in the range of 1 micron to 1 centimeter.

[0047] In another embodiment, one or more active compounds may be injected into packaging materials such as plastics, trays, bags, etc. One or more compositions may be applied to the surface of an object positioned adjacent to the perishable items. Examples of objects would be trays, cartons, etc.

[0048] In another embodiment, one or more compositions having one or more active compounds may be positioned in a carrier comprising a material capable of being molded. The carrier may be a wax, a paste-like material, a porous structure, or a microemulsion dispersed in a gel-like substance, among others. The carrier may be formed into a variety of shapes defining a range of surface to volume (S / V) ratios. The surface to volume ratio of the carrier form may also affect the rate of release of the one or more active compounds. The distance (d) that the one or more active compounds must travel from a first position within the carrier to the surface of the carrier may also affect the rate of release of the one or more compositions. For example, but by no means limiting, a spherical particle configuration will have a radius d. As a general rule, the total surface area of ​​the particle configuration is ~d 2 , and the volume of the particle configuration is ~d 3. Even if the basic shape is the same (e.g., beads, spheroids, etc.), the smaller the size of the radius, the higher the surface to volume ratio of the particle configuration. Therefore, the release rate of one or more active compounds from a smaller particle configuration will be faster than the release rate in a larger particle configuration. Therefore, when one or more active compounds need to be released faster into an environment adjacent to perishable items, a physical embodiment with a high S / V ratio will be advantageous. On the contrary, when one or more active compounds need to be released slower into an environment adjacent to perishable items, a physical embodiment with a small S / V ratio will be advantageous. For example, a delivery system with a carrier containing a wax in the form of a thin sheet will have a faster release rate of one or more active compounds than a delivery system with a carrier containing a wax in the form of a thicker disk. The increased surface to volume ratio may have a carrier form such as a honeycomb, a pit carrier, a rib carrier, a fin carrier, or a similar three-dimensional carrier to obtain an even larger surface area to volume ratio. In contrast, when a slower release rate is required, the same amount of one or more active compounds may have a carrier formed into a shape with a smaller surface to volume ratio, such as a large sphere, a cylinder, etc. In some embodiments, when the carrier has a diameter in the range of 1 micrometer to 1 centimeter, the S / V ratio ranges from 6000 to 0.6 1 / mm.

[0049] In another embodiment, the surface to volume ratio can be determined by changing the size of the particle configuration. For example, a sphere having one particle with a diameter of 1 cm will have a total volume of approximately 0.5 ml. If the size of the spherical particle configuration has a diameter of 1 mm, then the 1 cm sphere contains the same total amount of material as one thousand beads with a diameter of 1 mm, and the total surface area is ten (10) times that of the 1 cm spherical particle configuration. For a given total amount of material, simply changing the size of the particle will change the relative surface area in the same ratio. Therefore, the same amount of composition divided into multiple particle configurations releases the active compound faster than the same amount of a single particle configuration. For another example, a 1 gram (g) composition is disclosed, which has 0.1 grams of one or more active compounds dispersed in 0.9 grams of a carrier such as a diffusion-retarding matrix such as wax. If the delivery system is formed into a single spherical particle configuration, the particle configuration will have a slower release rate than when the delivery system is formed into multiple smaller spherical particle configurations.

[0050] In another embodiment, the amount of one or more active compounds released into an environment adjacent to perishable items can be varied by varying the amount of one or more compositions in different structures of the composition and / or carrier forms. In one example, in an environment adjacent to perishable items that has a "large headspace volume" that requires a higher release rate of one or more active compounds, a delivery system with a surface to volume ratio of 6000 to 0.6 1 / mm will be used. An example is a plurality of spherical particle configurations with a diameter of 1 mm and a surface to volume ratio of 6 1 / mm. In another embodiment, if the environment adjacent to perishable items has a "smaller headspace volume" that requires a lower release rate, a plurality of larger spherical particle configurations can be positioned within the environment adjacent to the perishable items.

[0051] In another embodiment, the carrier may have the form of one or more layers comprising one or more compositions. The carrier 100 may be a plurality of layers, as shown in FIGS. 2G to 2I. In one embodiment, the plurality of layers may be positioned between one or more diffusion barriers 115, thereby slowing down the release rate of one or more active compounds 110. In some embodiments, the carrier 100 may include a substrate 130, a bulk carrier material 101, a diffusion barrier 115, and a triggered release layer 125. In some embodiments, one or more active compounds may be present in any of the layers shown or described herein. In some embodiments, the triggered release layer 125 is triggered in response to humidity, temperature, etc. In another embodiment, the carrier 100 having a plurality of layers (as shown in FIGS. 2G to 2I) may also have a pulsed release rate. By positioning the biologically active compound 110 adjacent to one or more diffusion barriers 115A, 115B, a high concentration of one or more active compounds may be released in a shorter period of time. In some embodiments, this period of time can release high concentrations of one or more active compounds 110 into the environment adjacent to the perishable item at predetermined time intervals by alternating the placement of diffusion barriers 115A, 115B, and / or layers of biologically active compounds 110. In some embodiments, this is accomplished by including multiple S / V ratios formed from the same component, using different components 100 for different compounds 110, and then using multiple of these different forms of carrier 100, or a combination thereof. In one embodiment, a delivery system (or carrier) 100 having multiple layers can release a pulse of high concentrations of one or more active compounds, followed by a long period of no or very low high concentrations of one or more active compounds.

[0052] In some embodiments, porous paths may be included throughout the carrier 100. For example, in some embodiments, the entire carrier 100 may have varying degrees of porosity. This orientation effectively provides a continuous path from the inside of the bulk material to the outside in the open-pored structure. Compared to a single delivery system comprising one or more active compounds and a carrier, the open-pored structure provides a medium with different transport / permeation characteristics. For example, in the case where the pores of the open-pored structure remain "empty" and are only allowed to be filled with gas (e.g., ambient gas and / or gas released from the continuous phase), these pores can provide fast diffusion paths, thereby increasing the apparent bulk diffusion rate.

[0053] In another embodiment, the carrier of one or more delivery systems also includes one or more additive compounds. One or more additive compounds are used to adjust the release rate of the one or more active compounds to the environment by changing the physicochemical behavior of one or more active compounds. One or more additive compounds can be selected from but not limited to the group consisting of the following items: macrocyclic compounds such as cyclodextrin, urea, surfactants such as antioxidants, vitamin A, vitamin C, vitamin E, beta-carotene, polymers such as poly (N-isopropylacrylamide), etc., and ionic elements or compounds such as sodium chloride, calcium chloride, calcium carbonate and ammonium carbonate. For example, macrocyclic compounds can be combined with carriers. Macrocyclic compounds include a family of compounds with cage-like molecular structures, including cyclodextrin. This combination will form inclusion complexes with one or more active compounds, thereby slowing down the release rate of one or more active compounds from the carrier to the environment. Natural antioxidants, such as vitamin A, vitamin C, vitamin E, beta-carotene, etc., usually by reducing the vapor pressure of one or more active compounds, also have active control on the release of the composition. Natural ionic compounds, such as sodium chloride, calcium chloride, etc., also have active control on the release of the composition. The combination of ionic compounds and volatile compounds can increase or decrease the vapor pressure of the volatile compound, depending on the complex interactions between the molecules and their relative amounts in the carrier.

[0054] In other embodiments, the rate of release of one or more active compounds from the carrier to the environment may be affected by the presence of a stimulus. For example, the stimulus may be an additional compound that produces a competitive substitution system. In use, the competitive substitution system includes adding an additional compound to the delivery system. The carrier of the delivery system may have a greater affinity for the additional compound than the compound already combined in the composition of the delivery system. The competitive substitution system will replace the compound already combined in the composition with the additional compound. By way of example, but by no means limiting, in some embodiments, ethylene is added to the delivery system to replace the compound present in the composition. Therefore, the competitive release system responds to the increase of ethylene produced by the ripening of fruits or vegetables after harvest by replacing and thus releasing the compound in the composition of the delivery system with antifungal properties. In one embodiment, the presence of moisture in the delivery system may cause the compound in the composition to be released into the environment near the perishable item at an increased rate. In another embodiment, the delivery system may have a barrier layer combined with one or more active compounds. The barrier layer of the delivery system may be sensitive to temperature and / or humidity. For example, modified cellulose, such as methylcellulose, has a lower critical solution temperature (LCST) that can be designed to exist within a specific temperature range. Methylcellulose has a LCST of ~45°C. Below 45°C, methylcellulose is water soluble and will absorb water and transform into a gel-like physical state. Above 45°C, methylcellulose will expel water and will transform into a solid-like state. Diffusion barriers can have changing permeabilities in response to fluctuations in temperature and humidity, and thus adjust the release rate of the delivery system based on the environment.

[0055] In another embodiment, the composition of the delivery system can respond to the presence of one or more environmental conditions by increasing or decreasing the size of the delivery system. The compound can be cross-linked to allow the delivery system to hydrolyze or oxidize in response to one or more environmental conditions. Examples of environmental conditions include, but are not limited to, an increase in water in the atmosphere surrounding the perishable item, an increase in oxygen present in the atmosphere surrounding the perishable item, and the like. For example, a polymer carrier cross-linked by an ester bond is unstable and hydrolyzes under high humidity. The structure of such a carrier, including its permeability and porosity, will change when exposed to high humidity, thereby regulating the release rate of the delivery system.

[0056] In another embodiment, one or more delivery systems comprise one or more active compounds and a plurality of vesicles. The one or more active compounds are positioned in a plurality of vesicles forming a nanoemulsion or microemulsion. The size of the plurality of vesicles may range from about ten nanometers to about one micron. The delivery system may be formed to be thermodynamically stable or metastable by adding, but not limited to, one or more surfactants and using suitable processing methods.

[0057] Microemulsions can be very complex and contain many compounds, as a conceptual model it has at least three different components. For example, an oil-in-water (O / W) emulsion will have a surfactant, a continuous phase (such as water), and a discontinuous dispersed phase (such as oil) trapped inside the vesicles. Depending on the relative proportions of these components, a variety of microstructures can be formed.

[0058] In one embodiment, one or more delivery systems comprising a plurality of vesicles and one or more active compounds (particularly one or more essential oils or one or more essential oil components) and the dispersion of the delivery system in a continuous phase such as water can affect the overall release of one or more active compounds to the environment. It will be appreciated by those of ordinary skill in the art that the delivery system can be altered by changing the relative ratio of one or more active compounds. It will also be appreciated by those of ordinary skill in the art that the use of various surfactants, emulsifiers, and the size of a plurality of vesicles can form various permeabilities for one or more active compounds positioned within a plurality of vesicles (or entering the continuous phase from the vesicle surface / epidermis). In addition, the modification of one or more active compounds and the characteristics of the continuous phase can moderate the release rate. In another embodiment, changing the ratio of one or more active compounds in the emulsion can moderate the release rate of the one or more active compounds from the vesicles to the environment. In other embodiments, a delivery system having vesicles and / or microemulsions containing one or more active compounds can be suspended in a polymer matrix having a permeability that depends on the temperature and humidity of the environment surrounding the delivery system.

[0059] In another embodiment, the one or more delivery systems may be an emulsion of one or more active compounds having oil-like properties prepared in an aqueous continuous phase with one or more gelling agents. After the emulsion is formed, a portion of the water in the aqueous continuous phase may be evaporated, resulting in the formation of a delivery system in a gel-like state in which the one or more active compounds having oil-like properties are dispersed throughout in the form of a microemulsion.

[0060] In another embodiment, one or more delivery systems comprise one or more active compounds positioned in one or more capsules. In one embodiment, one or more active compounds can be combined with a gelatinous material. The size of one or more capsules can be in the range of about 0.05 cm to about 3.0 cm. One or more capsules can have a shell. The shell of one or more capsules can be made up of materials that one or more active compounds can penetrate. For example, the material can include but is not limited to cellulose, polymers, natural sugar polymers such as alginate, carrageenan, chitosan, synthetic polymers such as polyethylene glycol, etc. The total release rate of one or more active compounds can be controlled by selecting the material for one or more capsules and the thickness of the material selected for one or more capsules.

[0061] In another embodiment, a delivery system having a composition comprising one or more active compounds and a carrier can be positioned in one or more capsules of macroscopic size. The macroscopic size capsule has a diameter of about 0.2 cm or greater. An example is a delivery system placed in a capsule having a diameter of 0.5 cm, which includes a composition of a physical embodiment with a powder or granules combined with a wax or gel carrier. One or more capsules may contain a material that one or more active compounds can penetrate. The release rate of one or more active compounds may be affected by the material and / or thickness of the capsule shell. In another embodiment, the release rate can be affected by distributing an equal amount of the composition in one or more capsules of smaller size but greater number, which results in a higher surface to volume ratio. Typically, this will result in a faster release rate of one or more active compounds in an embodiment utilizing one or more capsules.

[0062] In one embodiment, the delivery system may include two or more compositions with different release requirements. For example, the delivery system may have a faster release rate composition 1 (C1), which results in C1 being released first into the environment adjacent to the perishable item, and a slower release rate composition 2 (C2), which results in C2 being released second into the environment adjacent to the perishable item. These releases may be sequential, but they may also occur simultaneously, at different rates.

[0063] Any suitable form (carrier, vesicle, microemulsion, capsule, etc.) of the above-mentioned one or more delivery systems can be arranged in various macro configurations, thereby producing different surface to volume ratios. Generally, when one or more active compounds need to be released into the environment at a faster release rate, a delivery system with a high surface to volume ratio will be advantageous. For example, a carrier containing a wax with one or more active compounds is pressed into a thin flat sheet. Alternatively, the delivery system can be formed into a honeycomb or similar pattern to obtain an even larger surface area under the same occupied area. In some embodiments, the composition can be formed into a flat or patterned sheet, including a honeycomb structure, which is conformable to any suitable surface in the interior or environment of a container, package, box. In some embodiments, the composition configured to conform can be attached, coated, laminated or otherwise fixed on a surface, container, box or package. In contrast, when a slower release rate is required over a longer period of time, the delivery system can be formed into a shape with a smaller surface to volume ratio, such as a large sphere or cylinder. Another way to control the surface to volume ratio is to form a delivery system by using different particle sizes of the same basic shape. For a given total amount of material, simply changing the size of the particles will change the relative surface area in the same ratio. All else being equal, the same amount of one or more active compounds will be released at a faster release rate when the one or more active compounds are made into smaller particles than when they are ground to a coarser size. In summary, the overall release rate can be controlled by any one or any combination of these macrogeometric choices of the delivery system.

[0064] In some embodiments, one or more diffusion layers 115A, 115B may be applied separately to the surface of the composition containing one or more active compounds 110 to slow down the total release rate of the one or more active compounds, as shown in FIG2H. In one embodiment, one or more diffusion layers 115A, 115B may or may not have active compounds. In another embodiment, one or more diffusion layers may be configured as one diffusion layer 115A adjacent to one or more diffusion layers 115B, as shown in FIG21. In this embodiment, each diffusion layer of the one or more diffusion layers may have the same active compound, different active compounds, or no active compound present in the diffusion layer. An example of a diffusion layer configured as one diffusion layer adjacent to one or more diffusion layers is a plurality of diffusion layers (plastic wrap) wrapped around perishable items, with beeswax drops dispersed in a wax matrix with different compositions. One or more diffusion layers may be selected from a group consisting of natural polymers, synthetic polymers, paraffin wax, natural wax, paper, clay, ceramics, etc. The permeability of one or more diffusion layers may be determined by the thickness of one or more natural polymers, synthetic polymers, paraffin wax, wax, paper, clay, ceramics, etc. Furthermore, the permeability through these diffusion barriers can be determined or manipulated by the properties of the material, the thickness of the diffusion barrier, the micropatterning or patterning of the diffusion barrier, and any physical perforations in the diffusion layer. When higher permeability is desired, the relative proportion of microperforations on the surface of the diffusion barrier or the pore size of the microperforations can be increased.

[0065] Delivery systems consisting of all different embodiments (including differences in chemistry, shape, physical configuration, etc.) can be combined in a "package" or product where multiple delivery systems function independently within close proximity to each other. The multiple delivery systems produce an overall release of one or more active compounds that may be difficult to achieve with a single delivery system design. Specifically, the observed net release behavior of the multiple delivery systems will be the superposition of the responses of all of these delivery systems. For example, a fast-release component (such as a small spherical bead) and a slow-release component (such as a bag) with a different chemical nature and / or larger particles can work together to achieve a target concentration to obtain a biological result.

[0066] It will be appreciated by those skilled in the art that the present disclosure may also be applied to a variety of items, including but not limited to food, fibers, appliances, household cleaning products, health care environments, and building surfaces to maintain their integrity and prevent the presence of various fungi, molds, and other microorganisms. Such compositions may also be applied to building structures, plant parts, and even clothing items or shoes to preserve or reduce odors.

[0067] The ideas proposed here can also be extended to many other application areas outside the preservation of perishable items. For example, other food products that may be susceptible to corruption, such as mature cheese, cured meats, etc., can be protected with these technologies. In addition, since volatile antimicrobial active compounds generally have a spectrum of action specificity at the genus, species or strain level, volatile antimicrobial active compounds can be selected from those compounds that do not have an inhibitory effect on the growth of desired organisms (e.g., in moldy cheeses, such as Roquefort or Camembert cheeses) while inhibiting the organisms that cause corruption.

[0068] Other applications may include (1) environmental sanitation; for example, but not limited to, household cleaning solutions that are safe, natural, and do not require spatial precision; (2) healthcare applications, for example, but not limited to, the formation of biofilms on medical devices that come into direct contact with humans, such as by forming a biofilm-inhibiting solution that can act at a distance; (3) other industries where fungal or bacterial growth is a recurring problem, such as leather production; for example, veterinary services.

[0069] Example In the following examples, equilibrium vapor pressure is measured by allowing a sample to release volatiles in a closed container and measuring the concentration (vapor pressure) when equilibrium is reached under given conditions. Concentration in the gas phase (vapor pressure is measured by a handheld photoionization detector or gas chromatograph).

[0070] In some embodiments, a Schiff base is used, as described herein. Schiff bases contain weak covalent bonds, characterized by the presence of a double bond connecting the carbon and nitrogen atoms. Schiff bases can be prepared by forming a chemical bond between a primary amine and an aldehyde or ketone functional group.

[0071] For example, chitosan has a primary amine side chain. It will form a reversible bond with an aldehyde or ketone functional group along the polymer chain under mild conditions (50°C in dilute acetic acid solution). The resulting chitosan-aldehyde Schiff base is itself non-volatile, since chitosan is a large, non-volatile molecule. Volatile aldehydes can be reversibly attached to chitosan in this way. Under dry conditions, the Schiff base is highly stable, and the aldehyde remains attached. Under high humidity conditions, the Schiff base is unstable and reconverts into chitosan and the aldehyde, which is then released freely.

[0072] In the following examples, the aldehyde used is trans-2-hexenal. This is an example of a "smart" delivery system developed that responds to relative humidity (RH) and releases its trans-2-hexanal payload more under higher relative humidity conditions. Here, RT VP is the equilibrium vapor pressure (VP) measured in a wide-mouth bottle containing the sample at room temperature (RT), expressed in PPM, typically measured by a handheld photoionization detector. As can be seen in Table 1, the pure aldehyde has a very high volatility (VP of 6000 PPM). When it is made into a Schiff base, the VP is significantly reduced because the covalent bonds bind and delay the release of the aldehyde. In addition, due to the sensitivity of the covalent bonds in the Schiff base to humidity, the equilibrium VP changes with changes in humidity.

[0073] Table 1: Equilibrium vapor pressures at room temperature of compositions coated on paper test specimens of the same size.

[0074] FIG. 3 is an example diffusion cell according to the present technology. A diffusion cell can be used to measure the permeability of a film, membrane or plate of a material to a specific volatile compound. The material can be a single material, a heterogeneous blend or a composite material consisting of a structure defined by multiple layers or otherwise. The diffusion cell has two compartments separated by the material to be tested, which is formed as a flat sheet or a membrane. At time zero, a volatile compound whose diffusivity through the test material is to be studied is placed in one of the compartments. The other compartment is empty at time zero. In the initially empty compartment, the concentration of the compound in the gas phase is measured as a function of time. In the following figure, vapor pressure (VP) is a measure of concentration. This is schematically shown in FIG. 3.

[0075] FIG4 is a test fixture according to the present technology. The test fixture includes two compartments formed by stainless steel tubes. A flange between them is used to secure the test material between the compartments and form an airtight seal. When testing at elevated temperatures is required, the entire assembly is wrapped with heating tape.

[0076] In some embodiments, the film, membrane or plate has a thickness of about 0.15 mm. In some embodiments, the diameter of the membrane is 3 inches (or about 7.6 cm). High concentrations of volatile compounds are trapped in a known volume on one side of the membrane with a known exposed area. The volatiles are allowed to diffuse through the membrane and their concentration is measured on the other side as they pass through. The thickness and exposed area of ​​the membrane and the flux of the volatiles through the membrane can be used to calculate the permeability of the membrane to the volatiles and the diffusivity of the volatiles in the membrane material.

[0077] Figure 5 is a graph showing diffusion through an example membrane according to the present technology. On the horizontal axis is time in minutes. On the vertical axis is vapor pressure in parts per million (PPM). Plotted is the diffusion of C59 (a volatile compound of interest) through a polyethylene membrane.

[0078] Figure 6 is a graph showing diffusion through another example membrane according to the present technology. On the horizontal axis is time in hours. On the vertical axis is vapor pressure in parts per million (PPM). Plotted is C59 diffusion through a polypropylene membrane.

[0079] Figures 5-6 show the difference in permeability of two different materials of the same thickness to the same compound (denoted as C59). The polyethylene film is less permeable to the compound than the polypropylene film, as evidenced by the slower rise in compound concentration (vapor pressure) in the initially empty chamber. Thus, in some physical embodiments, a layer or structure made of one or more materials can be used to adjust the overall release rate.

[0080] PTFE, FEP, and PET membranes were also investigated, but diffusion through these membranes was too slow to reliably measure permeability and diffusion coefficients with the current test apparatus setup. Therefore, the permeability of the tested PTFE, FEP, and PET samples to C59 was much lower than that of the tested PP and PE samples.

[0081] Applying a wax diffusion barrier layer to the outside of a carrier containing an active compound can modulate compound vapor pressure and release rate. Volatile essential oil compounds (EOCs) are loaded into a fiber-based matrix as a pure liquid or encapsulated in a carrier (natural oil or emulsion). The matrix is ​​then coated in a wax diffusion barrier layer, which modulates the rate at which the EOC can be released from the matrix. In this case, the wax diffusion barrier layer also prevents the matrix and carrier from absorbing moisture from the environment, making the system less sensitive to moisture. Representative results are shown in Table 2. Table 2 also shows the VP differences obtained by changing the matrix material without wax.

[0082] Table 2: Equilibrium vapor pressures of various matrix materials.

[0083] The wax diffusion barrier layer can also modulate the vapor pressure of compounds on ceramic-based substrates. The EOC is encapsulated in an emulsion carrier, applied to a cardstock substrate, and cured with a calcium carbonate curing agent to form a ceramic-based matrix. The coated card is then coated with one or two layers of paraffin wax. Thicker wax diffusion barriers reduce EOC release more than thinner barriers, as evidenced by the decreasing equilibrium vapor pressure with increasing barrier layer thickness.

[0084] FIG. 7 is a graph showing the vapor pressure of a wax carrier according to the present technology (as shown in Table 3). The horizontal axis is time in days. The vertical axis is vapor pressure in PPM. The dotted line represents a single wax layer, while the solid line represents two wax layers, as shown in FIG. 2H.

[0085] Table 3: Equilibrium vapor pressures of various matrix materials.

[0086] Applying polymeric diffusion barriers can also modulate compound vapor pressure and release rate. EOCs were encapsulated in a latex carrier, applied to a cardstock substrate, and cured with a calcium carbonate curing agent. The coated cards were then laminated with polypropylene (PP) films of varying thicknesses. Thicker films reduced EOC release more than thinner films (Table 4).

[0087] FIG8 is a graph showing the vapor pressure of a PP film carrier according to the present technology (as shown in Table 4). The horizontal axis is time in days. The vertical axis is vapor pressure in PPM. The dashed line with round nodes represents a thin PP film, and the dashed line with square nodes represents a thick PP film.

[0088] Table 4: Equilibrium vapor pressures of various matrix materials.

[0089] The results show that changing the surface area to volume ratio of the carrier matrix, while keeping the composition constant, can change the release profile of the active compound without significantly changing the equilibrium vapor pressure of the composition. Particles with higher surface area release more compound per unit time (faster), while solid plates of the same composition and the same total volume release volatile compounds more slowly over time. Table 5 shows that the final equilibrium pressure in the closed jar is essentially the same as expected, regardless of the physical configuration (plates versus particles). This is because the differences between physical configurations do not affect the equilibrium state, only the speed at which it is reached.

[0090] Table 5 FIG9 shows the evolution of vapor pressure over time measured in the same leaking container according to the present technology. The horizontal axis is time in days. The vertical axis is vapor pressure in PPM. The solid line is a 1g oil gel sheet bag, while the dashed line is a 1g oil gel granule bag.

[0091] In one case, a granule bag contains a plurality of particles obtained by grinding a solid piece of a carrier matrix containing the active compound into particles. Therefore, it has a high surface to volume ratio. In contrast, a plate bag contains a single plate-like compound block of the compound, thereby having a smaller surface to volume ratio. The measured change in vapor pressure (VP) over time is a measure of the compound release rate. A granule bag with a high surface area to volume ratio releases its volatile compound much faster than a plate bag.

[0092] A series of simulation results were obtained assuming realistic inputs. The molecular diffusion rate through beeswax was previously estimated to be 1.4E-12 m^2 / s. This is the value used in the simulations unless otherwise stated.

[0093] Unless otherwise noted, most of the cases modeled included a volatile compound source in an empty, larger 10 cm x 10 cm box (the compound source at the bottom of Figure 10). The simulations explored the concentrations in the box and the concentration distribution in the compound source as a function of various physical structure variations and material property variations.

[0094] FIG. 10 is an example geometry of a carrier for simulation according to the present technology. As shown, the box has a first width W1 and a first height H1. The volatile compound (or active compound) source has a second width W2 and a second height H2. In some embodiments, the large box is 10×10 centimeters, i.e., H1=10 cm and W1=10 cm. In some embodiments, the large box is a confined environment into which the volatile compound is released. In some embodiments, the compound source is a volatile compound source. In some embodiments, the compound source measures 2.24 cm×0.45 cm, i.e., H2=0.45 cm and W2=2.24 cm.

[0095] FIG. 11 shows the concentration profile of volatiles in a solid rectangular carrier matrix according to the present technology. On the horizontal axis is distance in centimeters. On the left vertical axis is distance in centimeters. On the right vertical axis is the concentration profile. Each carrier shown has a different permeability to volatiles at the same time point (72 hours) after starting with the same uniform concentration of 1 (arbitrary units) at time zero. The higher the permeability of the carrier material to volatiles (in other words, the higher the diffusion rate of the volatile compound through the carrier material), the more pronounced the concentration depletion toward the carrier surface.

[0096] FIG. 12 is a graph of different release profiles of the matrix from FIG. 11 according to the present technology. The horizontal axis is time in hours. The vertical axis is the instantaneous concentration in a two-dimensional (2D) box in moles / meter (m) depth. The change in gas concentration in the box due to the release of volatiles from the carrier matrix is ​​also shown. The results prove that by using materials with different diffusivities, it is possible to increase the release rate and adjust the release profile observed in an environment containing a carrier matrix. Delivery matrix materials with high diffusivities will release faster than delivery matrix materials with low diffusivities. FIG. 12 shows the concentration in the box when the carriers shown in FIG. 11 are placed one at a time (or independently) in an initially empty box. Therefore, six different scenarios are shown, showing that the observed release is different based on the permeability of the carrier to volatile compounds.

[0097] A change in the aspect ratio can significantly alter the release rate because it changes the surface to volume (S / V) ratio.

[0098] FIG. 13 shows the concentration profile of volatiles in rectangular carriers of different sizes according to the present technology. On the horizontal axis is distance in centimeters. On the left vertical axis is distance in centimeters. On the right vertical axis is the concentration profile. Each carrier has the same permeability and initially contains the same amount of the same volatile compounds at 72 hours of emission / release. They span a wide range of aspect ratios and S / V ratios.

[0099] FIG. 14 is a graph of different release profiles for matrices of different sizes from FIG. 13 according to the present technology. FIG. 14 shows significantly different release profiles observed in the same box containing these rectangular matrices. The horizontal axis is time in hours. The vertical axis is the instantaneous concentration in the two-dimensional (2D) box in moles / meter (m) depth. FIG. 14 shows what would be observed in an empty box when simulating carriers from FIG. 13 with different aspect ratios one at a time.

[0100] Also shown is the effect of outer layers of different diffusivities on the observed release rate. Figure 15 shows the construction of a carrier with a multilayer construction according to the present technology. In some embodiments, the carrier includes a core having a second width W2 and a second height H2. In some embodiments, the core has an outer layer of a third width W3.

[0101] Figure 16 shows a carrier with an outer layer of different diffusivities but the same thickness according to the present technology. The horizontal axis is the distance in centimeters. The left vertical axis is the distance in centimeters. The right vertical axis is the concentration distribution. When the outer layer has a high diffusivity, it quickly releases its payload, resulting in an initial burst and a rapid increase in concentration in the box (solid line with diamond nodes in Figure 17). When the outer layer has a much smaller diffusivity, it acts as a diffusion barrier for the core and slows down the entire release rate (solid line with "x"-shaped nodes in Figure 17). Figure 16 shows the concentration distribution in the carrier at the end of 100 hours. Initially, the compound is dispersed in both the core (2.24cm×0.45cm box, i.e., W2=2.24cm and H2=0.45cm) and the edge (0.40cm×0.45cm outer layer, where W3=0.40cm) to be released into the large box (not shown) around it. The diffusivity in the outer layer was varied by a factor of 100, from 0.1 to 10 times the diffusivity in the core layer.

[0102] FIG. 17 is a graph of different release profiles of the carrier of FIG. 16 according to the present technology. On the horizontal axis is time in hours. On the vertical axis is the instantaneous concentration in a two-dimensional (2D) box in moles per meter (m) depth. Solid lines with diamond-shaped nodes represent carriers with outer layers having the highest diffusivity, solid lines with circle-shaped nodes represent carriers with outer layers having intermediate diffusivity, and solid lines with "x"-shaped nodes represent carriers with outer layers having low diffusivity.

[0103] Figure 18 shows the concentration distribution of volatiles in a solid rectangular carrier matrix according to the present technology. The horizontal axis is the distance in centimeters. The left vertical axis is the distance in centimeters. The right vertical axis is the concentration distribution. In a simulation, the 3 sources (carriers) with equal permeability shown at the top of Figure 18 are placed in the same box at the same time. The top row of Figure 18 shows the sources with the same release rate (medium) at the end of the fixed duration. The bottom row of Figure 18 shows the sources with three different permeabilities (high-medium-low) for compounds at the end of the same fixed duration. In a second simulation, the bottom three carriers with different permeabilities are all placed in the box.

[0104] FIG. 19 is a graph of different release curves of the matrix from FIG. 18 according to the present technology. The horizontal axis is the time in days. The vertical axis is the concentration in the box. The line with a circular node represents the top row of FIG. 18. The line with a star node represents the bottom row of FIG. 18. Based on the fact that the second case (the bottom row of FIG. 18) is composed of 3 sources with different release rates, a significantly changed release curve is observed in the box containing them. Therefore, a blend including a carrier matrix with different permeability to the compound can also be used to adjust the release curve, even if their physical shapes are similar. Specifically, a fast release embodiment can be included to quickly reach the target concentration in the environment, while a slower release embodiment can be included to help maintain the desired concentration. This simulation shows how to achieve different total release curves by including multiple carriers with different permeabilities and intrinsic release rates. In this particular simulation, the intrinsic release rate of each carrier is changed by diffusivity / permeability. But as shown in other embodiments, the intrinsic release rate will also be affected by S / V ratio, physical patterning, aspect ratio, etc. Therefore, including different types of multiple carriers allows a wide range of net / total release rates.

[0105] FIG20 shows the concentration distribution of volatiles for different shapes according to the present technology. On the horizontal axis is the distance in centimeters. On the left vertical axis is the distance in centimeters. On the right vertical axis is the concentration distribution. The effect of achieving different S / V ratios and diffusion path lengths by changing the detailed shape was also simulated. This effect was simulated by placing different numbers of ridges (corrugations) on the base. In all cases, the total amount of sources remains the same, only their geometric shapes differ from each other.

[0106] Figure 21 is a graph according to the different release curves in the matrix of the different shapes of Figure 20 of the present technology.On the horizontal axis is the time in hours.On the vertical axis is the concentration in the box.Figure 21 shows the obtained concentration observed one by one in the same box containing each one in the source shown in Figure 20.As shown in Figure 21, only changing the physical topology, i.e. changing S / V and effective diffusion path, will cause different release curves.This effect also can be used for topology and the geometrical shape of custom source (carrier matrix) design, to realize the release curve of expectation.

[0107] FIG. 22 shows the concentration distribution of spherical volatiles according to the present technology. On the horizontal axis is the distance in millimeters. On the left vertical axis is the distance in millimeters. On the right vertical axis is the concentration distribution. It is also simulated that the release rate is affected by changing the total S / V ratio by dividing a large round ball into more and more small balls. In this simulation, the total volume of the spherical (ball-shaped) source (carrier matrix) and the total amount of compounds contained therein remain the same. Therefore, in terms of the total amount of materials and compounds included, several small balls can be equivalent to fewer larger balls. The only difference is the difference in the S / V ratio. Even if the total ball volume (the total amount of material included in the simulation) is the same, a larger number of smaller diameter balls will release their volatile payload faster than fewer larger balls.

[0108] FIG. 23 is a graph of different release profiles of the spherical volatiles of FIG. 22 according to the present technology. On the horizontal axis is time in hours. On the vertical axis is the instantaneous concentration in the box. FIG. 23 shows the relative size of each ball and the concentration distribution within the ball after the same duration. Plotted are 500 tiny balls, 100 very small balls, 50 small balls, 10 medium balls, and 1 large ball, each with the same amount of compound. As shown, a larger number of smaller balls has a higher diffusion rate than a single large ball.

Claims

1. A delivery system for reducing the decomposition rate of perishable items, the system comprising: One or more compositions, wherein the one or more compositions comprise at least one active compound; and at least one carrier configured to support the one or more compositions, wherein the at least one carrier comprises: A release rate modifying mechanism, wherein the release rate modifying mechanism is configured to adjust the release rate of the at least one active compound.

2. The system of claim 1, wherein the at least one active compound is selected from the group consisting of one or more volatile compounds, one or more non-volatile compounds, one or more plant immunostimulatory compounds, one or more ethylene-acting agent compounds, and combinations thereof.

3. The system of claim 1, wherein the release rate modifying mechanism is one or more diffusion barriers or one or more release layers.

4. The system of claim 3, wherein the permeability of the one or more diffusion barriers or the one or more release layers is determined by material selection, diffusivity, thickness, micropatterning, or a combination thereof.

5. The system of claim 3, wherein the one or more diffusion barriers are responsive to an environmental stimulus, wherein the environmental stimulus comprises temperature, humidity, or a combination thereof.

6. The system of claim 1, wherein the release rate modifying mechanism is the porosity of the at least one component of the carrier, the porosity being selected from macropores, mesopores, micropores, or combinations thereof.

7. The system of claim 1, wherein the release rate modifying mechanism is the shape of the at least one carrier, the shape being selected from the group consisting of disc-like forms, honeycomb forms, dimple forms, rib-like forms, fin-like forms, spherical forms, cylindrical forms, particles, irregularly shaped beads, shavings, powders, flakes, sheets, and combinations thereof.

8. The system of claim 7, wherein the at least one carrier has a plurality of surface to volume ratios.

9. The system of claim 8, wherein the at least one carrier is a plurality of carriers, and wherein each carrier in the plurality of carriers has a different surface to volume ratio than at least one other carrier.

10. The system of claim 8, wherein the at least one carrier is a flat patterned disk having a plurality of ridges, each ridge having a different ridge width and pitch.

11. The system of claim 1, wherein the carrier is selected from the group consisting of water, paraffin, petroleum wax, petroleum, natural wax, beeswax, natural and modified natural oils such as rapeseed oil, grapeseed oil, hydrogenated soybean oil, etc., resins or rosins, synthetic polymers, natural polymers or gums such as alginates, starches, carrageenan, agar, shellac, pectin, chitin, inulin, lignin, hyaluronic acid, chitosan, collagen, keratin, xanthan gum, gum arabic, mastic, guar gum, etc., ceramics, modified celluloses such as methylcellulose, ethylcellulose and hydroxypropyl methylcellulose, surfactants, mesoporous silica nanoparticles, microporous alumina, anodized alumina, activated carbon, zeolites, clays, metal carboxylates, inorganic compounds, and combinations thereof.

12. The system of claim 2, wherein the volatile compound is selected from the group consisting of trans-2-hexenal, trans-2-octenal, trans-2-nonenal, trans-2-decenal, trans-2-dodecenal, p-isopropylbenzaldehyde, citronellal, thymol, perillaldehyde, carvacrol, citral, carvone, menthol, borneol acetate, 1-octanol, terpinen-4-ol, linalool, trans-anethole, trans-cinnamaldehyde, ethyl octanoate, ethyl nonanoate, ethyl decanoate, methyl octanoate, methyl nonanoate, methyl decanoate, fenchol, borneol, camphor, methyl eugenol, menthol, methyl salicylate, methyl anthranilate, phenylethyl acetate, phenylacetic acid, cinnamic acetate, gamma-octalactone, gamma-decanoate, eucalyptol, geranium oil, lavender oil, Thyme oil, clove oil, (-)-bornyl acetate, (-)-terpinen-4-ol, (+)-carvone, (±)-citronellal, (R)-(+)-citronellal, (S)-(–)-citronellal, (R)-(+)-longifolia mint, thymol, 4-isopropylbenzaldehyde (cuminaldehyde), 4-allylanisole, cis-3,7-dimethyl-2,6-octadiene-l -alcohol, citronellol, trans-methyl cinnamate, myrcene, ocimene, terpineol, 1-methyl-3-methoxy-4-isopropylbenzene, menthol, menthone, isomenthone, vanillin, geranyl formate, palmitic acid, (S)-(-)-perillaldehyde, nootkatone, hinokitiol, d-limonene, s-limonene, -isopropyltoluene, nerolidol, 3-decen-2-one and combinations thereof.

13. The system of claim 2, wherein the non-volatile compound is selected from the group consisting of curcumin, chitosan, phytoalexins, phytoalexins, one or more preservatives, vitamin E, vitamin A, vitamin C, tocopherol, catechins, anthocyanidins, polyphenols, butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), and beta-carotene.

14. The system of claim 2, wherein the plant immunostimulatory compound is selected from the group consisting of pinene, camphene, terpinene, terpineol, chitosan, phytoalexin, phytoalexin, methyl salicylate, ethyl salicylate, methyl cinnamate, methyl jasmonate, jasmonic acid, cinnamic acid, salicylic acid, ethylene, p-aminobutyric acid, methyl salicylate, ethyl salicylate, methyl cinnamate, fructan, ethylene and hypersensitive protein.

15. The system of claim 2, wherein the ethylene-acting agent compound is selected from the group consisting of activated carbon, norbornadiene, resveratrol, sodium permanganate, potassium permanganate, vanillin, 1-methylcyclopropene, and combinations thereof.

16. The system of claim 1, wherein the carrier further comprises one or more additive compounds.

17. The system of claim 16, wherein the one or more additive compounds are selected from the group consisting of one or more macrocyclic compounds, surfactants, one or more antioxidants, urea, one or more polymers, and combinations thereof.

18. The system of claim 17, wherein the one or more antioxidants are selected from the group consisting of vitamin A, vitamin C, vitamin E, beta-carotene, tocopherol, butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), and combinations thereof.

19. The system of claim 1, wherein the carrier comprises a coating configured to protect the carrier from moisture, oxygen, or both moisture and oxygen.

20. The system of claim 1, wherein the one or more compositions further comprises at least one inactive compound.

21. A method for extending the life of perishable items, the method comprising: One or more delivery systems according to any one of claims 1 to 20 are placed in the area containing the perishable goods.

22. A delivery system for reducing the decomposition of perishable items, the system comprising: Multiple vesicles; one or more compositions positioned in the plurality of vesicles, wherein the one or more compositions comprise at least one active compound and at least one inactive compound; and at least one carrier configured to support the one or more compositions, wherein the at least one carrier comprises: A release rate modifying mechanism, wherein the release rate modifying mechanism is configured to adjust the release rate of the at least one active compound.

23. The system of claim 22, wherein the release rate modifying mechanism is one or more diffusion barriers.

24. The system of claim 22, wherein the release rate modifying mechanism is the porosity of the at least one carrier, the porosity being selected from macropores, mesopores, micropores, or combinations thereof.

25. The system of claim 22, wherein the release rate modifying mechanism is the shape of the at least one carrier, the shape being selected from the group consisting of disc-like forms, honeycomb forms, dimple forms, rib-like forms, fin-like forms, spherical forms, cylindrical forms, particles, irregularly shaped beads, shavings, powders, flakes, sheets, and combinations thereof.

26. The system of claim 22, wherein the at least one active compound is selected from the group consisting of: one or more volatile compounds; one or more non-volatile compounds; one or more plant immunostimulatory compounds; and one or more ethylene-acting agent compounds.

27. The system of claim 26, wherein the volatile compound is selected from the group consisting of trans-2-hexenal, trans-2-octenal, trans-2-nonenal, trans-2-decenal, trans-2-dodecenal, p-isopropylbenzaldehyde, citronellal, thymol, perillaldehyde, carvacrol, citral, carvone, menthol, borneol acetate, 1-octanol, terpinen-4-ol, linalool, trans-anethole, trans-cinnamaldehyde, ethyl octanoate, ethyl nonanoate, ethyl decanoate, methyl octanoate, methyl nonanoate, methyl decanoate, fenchol, borneol, camphor, methyl eugenol, menthol, methyl salicylate, methyl anthranilate, phenylethyl acetate, phenylacetic acid, cinnamic acetate, gamma-octalactone, gamma-decanoate, eucalyptol, geranium oil, lavender oil, Thyme oil, clove oil, (-)-bornyl acetate, (-)-terpinen-4-ol, (+)-carvone, (±)-citronellal, (R)-(+)-citronellal, (S)-(–)-citronellal, (R)-(+)-longifolia mint, thymol, 4-isopropylbenzaldehyde (cuminaldehyde), 4-allylanisole, cis-3,7-dimethyl-2,6-octadiene-l -alcohol, citronellol, trans-methyl cinnamate, myrcene, ocimene, terpineol, 1-methyl-3-methoxy-4-isopropylbenzene, menthol, menthone, isomenthone, vanillin, geranyl formate, palmitic acid, (S)-(-)-perillaldehyde, nootkatone, hinokitiol, d-limonene, s-limonene, -isopropyltoluene, nerolidol, 3-decen-2-one and combinations thereof.

28. The system of claim 26, wherein the non-volatile compound is selected from the group consisting of curcumin, chitosan, phytoalexins, phytoalexins, one or more preservatives, and vitamin E, vitamin A, vitamin C, and beta-carotene.

29. The system of claim 26, wherein the plant immunostimulatory compound is selected from the group consisting of pinene, camphene, chitosan, methyl jasmonate, salicylic acid, jasmonic acid, ethylene, beta-aminobutyric acid, and hypersensitive protein.

30. The system of claim 26, wherein the ethylene-acting agent compound is selected from the group consisting of norbornadiene, resveratrol, sodium permanganate, potassium permanganate, vanillin, and 1-methylcyclopropene.

31. A method for extending the life of perishable items, the method comprising: One or more delivery systems according to any one of claims 22 to 30 are placed in the area containing the perishable goods.

32. A delivery system for reducing the decomposition of perishable items, the system comprising: One or more compositions, wherein the one or more compositions comprise at least one active compound, at least one inactive compound, and a release rate modifying mechanism, wherein the release rate modifying mechanism is configured to adjust the release rate of the at least one active compound; and At least one carrier configured to support the one or more compositions.

33. The system of claim 32, wherein the release rate modifying mechanism is the structure of the one or more compositions.

34. The system of claim 33, wherein the structure of the one or more compositions is selected from the group consisting of beads, particles, pellets, honeycomb structures, porous structures, and combinations thereof.

35. The system of claim 32, wherein the at least one carrier comprises a second release rate modifying mechanism, wherein the release rate modifying mechanism is configured to adjust the release rate of the one or more compositions.

36. The system of claim 32, wherein the at least one active compound is selected from the group consisting of one or more volatile compounds; one or more non-volatile compounds; one or more plant immunostimulatory compounds; and one or more ethylene-acting agent compounds, and combinations thereof.

37. The system of claim 35, wherein the second release rate modifying mechanism is a diffusion barrier.

38. The system of claim 35, wherein the second release rate modifying mechanism is the porosity of the carrier, the porosity being selected from macropores, mesopores, or micropores.

39. The system of claim 35, wherein the second release rate modifying mechanism is the shape of the carrier, the shape being selected from the group consisting of a disk form, a honeycomb form, a dimple form, a rib form, a fin form, a spherical form, a cylindrical form, and combinations thereof.

40. A method for extending the life of a perishable item, the method comprising: One or more delivery systems according to any one of claims 32 to 39 are placed in the area containing the perishable goods.

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