Patent Publication Number: US-11642208-B2

Title: Sample container with peelable seal and access port

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 16/460,920, entitled “Sample Container with Peelable Seal and Access Port,” filed Jul. 2, 2019, which claims priority to U.S. Provisional Application Ser. No. 62/694,662, entitled “Sample Container with Peelable Seal and Access Port,” filed Jul. 6, 2018, each of which is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND 
     The embodiments described herein relate containers for storing and transporting tissue and other biological material. More particularly, the embodiments described herein relate to devices and methods including containers having a peelable seal and an access port for use in tissue implant procedures. 
     Known tissue implants and/or grafts are used in a variety of procedures to repair or replace damaged tissue. Such procedures can include implanting bone or gum tissue to address dental or periodontal issues, bone grafting to repair fractures, and tendon grafting to repair damaged ligaments and/or tendons (e.g., repair of a torn anterior cruciate ligament), to name just a few. In many instances, the tissue implant is not taken from the patient&#39;s body (i.e., is not an autograft), but rather is from another source, such as from a human cadaver (i.e., an allograft) or an animal (i.e., a xenograft). Known non-autologous grafts are often stored in a dried condition within a sterile package, and thus must be rehydrated or otherwise prepared prior to use. 
     Some known procedures for preparing or rehydrating a tissue implant include removing the tissue implant from the sterile package and placing the tissue graft in an opened container (e.g., a basin) that contains rehydration liquid. The tissue implant is then manipulated within the open container to facilitate rehydration. Such manipulation can include, for example, manually submerging the tissue implant within the rehydration fluid (in an effort to achieve consistent rehydration), agitating the tissue implant and/or rehydration fluid, and the like. After rehydration, the tissue implant is then removed from the rehydration container for use. This procedure can result in compromised sterility (e.g., due to the repeated transfer of the tissue graft), inconsistent rehydration due to inconsistent exposure of the tissue implant in the open container, and longer rehydration times. Additionally, because of the repeated movement of the tissue implant (e.g., during transfer and while in the rehydration container) possible damage to the tissue implant can occur. 
     Other known procedures include receiving the tissue implant in a rigid tray, removing a lid from the tray, and completing the rehydration procedure in the open tray. Although this method eliminates the step of transferring the tissue implant from its sterile packaging, such rigid packaging can be bulky and less desirable for tissue storage facilities. Moreover, the rehydration still occurs in an open top container and can involve agitating, submerging, or moving the tissue implant, which can result in damage to the tissue implant. 
     Yet other known procedures including rehydrating the tissue implant with a sterile, flexible pouch. Such systems and methods often provide inadequate support for the tissue implant, and thus the implant can be easily damaged during the rehydration operation. 
     Thus, a need exists for improved containers and methods for storing, transporting, and rehydrating tissue and other biological material. 
     SUMMARY 
     Containers and methods for storing tissue and other biological materials are described herein. In some embodiments, an apparatus includes a flexible container, a port, and a support structure. The container includes a first layer coupled to a second layer to define a storage volume within which a tissue specimen can be contained. The first layer is characterized by a first stiffness and the second layer characterized by a second stiffness. An edge of the first layer is spaced apart from an edge of the second layer to define an opening into the storage volume. The edge of the first layer and the edge of the second layer are configured to form a peelable seal that hermetically seals the storage volume such that the first layer can be peeled away from the second layer to expose the storage volume. The port is coupled to the flexible container and allows fluid communication between the storage volume and an external volume. The support structure is configured to support the tissue specimen within the storage volume and is characterized by a third stiffness. The third stiffness is greater than the first stiffness and the second stiffness. 
     In some embodiments, a method includes inserting a tissue specimen into a storage volume defined between a first layer of a flexible container and a second layer of the flexible container. The tissue specimen is inserted via an opening defined by an edge of the first layer and an edge of the second layer. The flexible container includes a port configured to allow fluid communication between the storage volume and an external volume. The tissue specimen is positioned within the storage volume between the first layer and a support structure. A stiffness of the support structure is greater than each of a stiffness of the first layer and a stiffness of the second layer. The edge of the first layer is then coupled to the edge of the second layer to form a peelable seal that hermetically seals the storage volume. The peelable seal is configured such that the first layer can be peeled away from the second layer to expose the storage volume. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS.  1 - 4    are schematic illustrations of a container assembly according to an embodiment, in a first configuration ( FIG.  1   ), a second configuration ( FIG.  2   ), a third configuration ( FIG.  3   ), and a fourth configuration ( FIG.  4   ). 
         FIG.  5    is a flow diagram of a method of preparing a tissue specimen for storage according to an embodiment. 
         FIG.  6    is a flow diagram of a method of rehydrating a tissue specimen for use in a procedure according to an embodiment. 
         FIG.  7    is a top view and  FIG.  8    is a side view of a container assembly in an opened configuration, according to an embodiment. 
         FIG.  9    is a top view of a support structure of the container assembly shown in  FIGS.  7  and  8   . 
         FIG.  10    is a top view of the container assembly shown in  FIGS.  7  and  8    with the support structure and a tissue specimen contained therein. 
         FIG.  11    is a top view of the container assembly shown in  FIG.  10    in a sealed configuration. 
         FIG.  12    is a top view and  FIG.  13    is a side view of a container assembly in an opened configuration, according to an embodiment. 
         FIG.  14    is a top view of the container assembly shown in  FIGS.  12  and  13    with the support structure and a tissue specimen contained therein. 
         FIG.  15    is a top view of the container assembly shown in  FIG.  13    in a sealed configuration. 
         FIG.  16    is a top view and  FIG.  17    is a side view of a support structure, according to an embodiment. 
         FIG.  18    is a top view of a support structure, according to an embodiment. 
         FIG.  19    is a side view and  FIG.  20    is a top view of a container assembly in an opened configuration, according to an embodiment. 
         FIG.  21    is a side view and  FIG.  22    is a top view of the container assembly shown in  FIGS.  19  and  20    in a sealed configuration with a tissue specimen contained therein. 
         FIG.  23    is atop view of a container assembly in an opened configuration, according to an embodiment. 
         FIG.  24    is a top view and  FIG.  25    is a side view of the container assembly shown in  FIG.  23    in a sealed configuration with a tissue specimen contained therein. 
     
    
    
     DETAILED DESCRIPTION 
     The embodiments described herein can advantageously be used in a wide variety of tissue storage, transportation, and implantation operations. In particular, the flexible container designs described herein can allow for a tissue specimen to be loaded and sealed at the point of loading (e.g., a tissue bank) via a peelable seal. The loaded flexible container can be used to both store and rehydrate the tissue specimen within the same container. Moreover, although the container is flexible and easily adaptable for storage, the embodiments described herein include a support member that provides structural support for the tissue specimen during packaging, storage, and rehydration. In this manner, the embodiments described herein can result in more efficient tissue sample storage and rehydration with less damage to the tissue specimen. 
     In some embodiments, an apparatus includes a flexible container, a port, and a support structure. The container includes a first layer coupled to a second layer to define a storage volume within which a tissue specimen can be contained. The first layer is characterized by a first stiffness and the second layer characterized by a second stiffness. An edge of the first layer is spaced apart from an edge of the second layer to define an opening into the storage volume. The edge of the first layer and the edge of the second layer are configured to form a peelable seal that hermetically seals the storage volume such that the first layer can be peeled away from the second layer to expose the storage volume. The port is coupled to the flexible container and allows fluid communication between the storage volume and an external volume. The support structure is configured to support the tissue specimen within the storage volume and is characterized by a third stiffness. The third stiffness is greater than the first stiffness and the second stiffness. 
     In some embodiments, an apparatus includes a flexible container, a port, a tissue specimen within the flexible container, and a support structure. The flexible container includes a first layer coupled to a second layer to define a storage volume within which the tissue specimen is contained. The first layer is characterized by a first stiffness and the second layer characterized by a second stiffness. An edge of the first layer is coupled to an edge of the second layer to form a peelable seal that hermetically seals the storage volume such that the first layer can be peeled away from the second layer to expose the storage volume. The port is coupled to the flexible container and allows fluid communication between the storage volume and an external volume. The support structure is coupled to the flexible container and is positioned to support the tissue specimen within the storage volume. The support structure is characterized by a third stiffness that is greater than the first stiffness and the second stiffness. 
     In some embodiments, an apparatus includes a flexible container, a port, and a support structure. The flexible container includes a first layer, second layer, and a third layer. The first layer is coupled to the second layer to define a storage volume within which a tissue specimen can be contained. The third layer is coupled to the second layer to define a support volume. An edge of the first layer is spaced apart from an edge of the second layer to define an opening into the storage volume, the edge of the first layer and the edge of the second layer configured to form a peelable seal that hermetically seals the storage volume such that the first layer can be peeled away from the second layer to expose the storage volume. The port is coupled to the flexible container and allows fluid communication between the storage volume and the external volume. The support structure is within the support volume and is configured to support the tissue specimen within the storage volume. 
     In some embodiments, a method includes inserting a tissue specimen into a storage volume defined between a first layer of a flexible container and a second layer of the flexible container. The tissue specimen is inserted via an opening defined by an edge of the first layer and an edge of the second layer. The flexible container includes a port configured to allow fluid communication between the storage volume and an external volume. The tissue specimen is positioned within the storage volume between the first layer and a support structure. A stiffness of the support structure is greater than each of a stiffness of the first layer and a stiffness of the second layer. The edge of the first layer is then coupled to the edge of the second layer to form a peelable seal that hermetically seals the storage volume. The peelable seal is configured such that the first layer can be peeled away from the second layer to expose the storage volume. 
     In some embodiments, a method of rehydrating a tissue specimen includes conveying a rehydration fluid into a storage volume defined between a first layer of a flexible container and a second layer of the flexible container. The rehydration fluid is conveyed via a port coupled to the flexible container. The storage volume contains a tissue specimen hermetically sealed therein, and the tissue specimen is supported by a support structure. A stiffness of the support structure is greater than each of a stiffness of the first layer and a stiffness of the second layer. The rehydration fluid is maintained within the storage volume to rehydrate the tissue specimen. The first layer is then peeled from the second layer to expose the storage volume. The method further includes removing the rehydrated tissue specimen from the storage volume after the first layer is peeled. 
     As used herein, the term “about” when used in connection with a referenced numeric indication means the referenced numeric indication plus or minus up to 10% of that referenced numeric indication. For example, the language “about 50” covers the range of 45 to 55. Similarly, the language “about 5” covers the range of 4.5 to 5.5. 
     As used herein, the term tissue specimen or tissue graft refers to any material that can be used in a tissue repair procedure. Thus, a tissue specimen or a tissue graft can include any of a skin graft, bone tissue, fiber tissue (e.g., tendon tissue, ligament tissue, or the like), ocular tissue (e.g. corneal implants), or the like. A tissue specimen or a tissue graft can include a portion of tissue harvested from a donor or a structure component that includes both tissue and non-tissue material (e.g., a synthetic matrix that includes tissue therein). For example, a tissue specimen or a tissue graft can include bone tissue that also includes bone cement or other non-tissue components. As another example, a tissue specimen or tissue graft can include bone chips including cortical bone chips, cancellous bone chips, and corticocancellous bone chips, and/or bone chips with viable bone lineage committed cells. 
     As used herein, the term “stiffness” relates to an object&#39;s resistance to deflection, deformation, and/or displacement produced by an applied force, and is generally understood to be the opposite of the object&#39;s “flexibility.” For example, a layer or structure of a container with greater stiffness is more resistant to deflection, deformation and/or displacement when exposed to a force than is a layer or structure of the container having a lower stiffness. Similarly stated, a container (or layer) having a higher stiffness can be characterized as being more rigid than a container (or layer) having a lower stiffness. Stiffness can be characterized in terms of the amount of force applied to the object and the resulting distance through which a first portion of the object deflects, deforms, and/or displaces with respect to a second portion of the object. When characterizing the stiffness of an object, the deflected distance may be measured as the deflection of the portion of the object different than the portion of the object to which the force is directly applied. Said another way, in some objects, the point of deflection is distinct from the point where the force is applied. 
     Stiffness (and therefore, flexibility) is an extensive property of the object being described, and thus is dependent upon the material from which the object is formed as well as certain physical characteristics of the object (e.g., cross-sectional shape, thickness, boundary conditions, etc.). For example, the stiffness of an object can be increased or decreased by selectively including in the object a material having a desired modulus of elasticity, flexural modulus and/or hardness. The modulus of elasticity is an intensive property of (i.e., is intrinsic to) the constituent material and describes an object&#39;s tendency to elastically (i.e., non-permanently) deform in response to an applied force. A material having a high modulus of elasticity will not deflect as much as a material having a low modulus of elasticity in the presence of an equally applied stress. Thus, the stiffness of the object can be decreased, for example, by introducing into the object and/or constructing the object of a material having a relatively low modulus of elasticity. Similarly, the flexural modulus is used to describe the ratio of an applied stress on an object in flexure to the corresponding strain in the outermost portions of the object. The flexural modulus, rather than the modulus of elasticity, is often used to characterize certain materials, for example plastics, that do not have material properties that are substantially linear over a range of conditions. An object with a first flexural modulus is more elastic and has a lower strain on the outermost portions of the object than an object with a second flexural modulus greater than the first flexural modulus. Thus, the stiffness of an object can be reduced by including in the object a material having a relatively low flexural modulus. 
     Moreover, the stiffness (and therefore flexibility) of an object constructed from a polymer can be influenced, for example, by the chemical constituents and/or arrangement of the monomers within the polymer. For example, the stiffness of an object can be reduced by decreasing a chain length and/or the number of branches within the polymer. The stiffness of an object can also be reduced by including plasticizers within the polymer, which produces gaps between the polymer chains. 
     The stiffness of an object can also be increased or decreased by changing a physical characteristic of the object, such as the shape or cross-sectional area of the object. For example, an object having a length and a cross-sectional area may have a greater stiffness than an object having an identical length but a smaller cross-sectional area. As another example, the stiffness of an object can be reduced by including one or more stress concentration risers (or discontinuous boundaries) that cause deformation to occur under a lower stress and/or at a particular location of the object. Thus, the stiffness of the object can be decreased by decreasing and/or changing the shape of the object. 
     As used in this specification, specific words chosen to describe one or more embodiments and optional elements or features are not intended to limit the invention. For example, spatially relative terms—such as “beneath”, “below”, “lower”, “above”, “upper”, “proximal”, “distal”, and the like—may be used to describe the relationship of one element or feature to another element or feature as illustrated in the figures. These spatially relative terms are intended to encompass different positions (i.e., translational placements) and orientations (i.e., rotational placements) of a device in use or operation in addition to the position and orientation shown in the figures. For example, if a device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be “above” or “over” the other elements or features. Thus, the term “below” can encompass both positions and orientations of above and below. A device may be otherwise oriented (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. Likewise, descriptions of movement along (translation) and around (rotation) various axes includes various spatial device positions and orientations. 
     Similarly, geometric terms, such as “parallel”, “perpendicular”, “round”, or “square”, are not intended to require absolute mathematical precision, unless the context indicates otherwise. Instead, such geometric terms allow for variations due to manufacturing or equivalent functions. For example, if an element is described as “round” or “generally round”, a component that is not precisely circular (e.g., one that is slightly oblong or is a many-sided polygon) is still encompassed by this description. 
     In addition, the singular forms “a”, “an”, and “the” are intended to include the plural forms as well, unless the context indicates otherwise. The terms “comprises”, “includes”, “has”, and the like specify the presence of stated features, steps, operations, elements, components, etc. but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, or groups. 
       FIGS.  1 - 4    are schematic illustrations of a container assembly  100  according to an embodiment. The tissue container assembly  100  is shown in a first (or open and unloaded) configuration ( FIG.  1   ), a second (or partially loaded) configuration ( FIG.  2   ), a third (or loaded and sealed) configuration ( FIG.  3   ), and a fourth (opened) configuration ( FIG.  4   ). The container assembly  100  (and any of the container assemblies described herein) can be used to perform any of the methods described herein, such as the method  10  of preparing a tissue specimen for storage (see  FIG.  5   ) and/or the method  20  of rehydrating a tissue specimen for use in a procedure according to an embodiment (see  FIG.  6   ). As described herein, the container assembly  100  provides a single container that can be used for both storage and rehydration. The container provides sufficient support for the tissue specimen or graft G, which can be very fragile during and after rehydration. As shown, the container assembly  100  includes a flexible container  105 , a port  150  coupled to the flexible container  105 , and a support structure  160 . 
     The flexible container  105  includes a first end portion  101 , a second end portion  102 , and a pair of side edges  103  between the first end portion  101  and the second end portion  102 . The flexible container  105  defines a longitudinal axis A L  that extends longitudinally from the first end portion  101  and the second end portion  102 . The flexible container  105  is constructed from a first layer  110  and a second layer  120  coupled together to define a storage volume  106 . As shown in  FIG.  1   , when the container assembly  100  is in the first (or opened) configuration, an edge  111  of the first layer  110  is spaced apart from an edge  121  of the second layer  120  to define an opening  107  into the storage volume  106 . The opening  107  can be of any suitable size to facilitate loading of the support structure  160  and the tissue specimen G (also referred to as a tissue graft), as described herein. For example, although the opening  107  is shown as extending across the full length of the first end portion  101  of the flexible container  105 , in other embodiments, the opening  107  can extend across only a portion of the length of an end or a side of the flexible container  105 . 
     The first layer  110  can be constructed of any suitable material, and has a first stiffness. For example, in some embodiments, the first layer  110  can be a thin, peelable film, such as, for example, a heat seal-coated (HSC) material, a polyethylene material, a polyvinyl chloride (PVC) material, a polyamide material, a polyester-based material, or any combination of such materials, including laminates constructed from multiple different materials. The first layer  110  can have any suitable thickness to provide the desired strength, flexibility, and sealing characteristics. For example, in some embodiments, the first layer  110  can be between about 50 microns (0.050 mm) and about 200 microns (0.200 mm). In other embodiments, the first layer can be between about 50 microns (0.050 mm) and about 100 microns (0.100 mm). 
     The second layer  120  can be constructed of any suitable material, and has a second stiffness. For example, in some embodiments, the second layer  120  can constructed from the same material and/or can have the same stiffness as the first layer  110 . In other embodiments, the second layer  120  can be constructed from a different material and the second stiffness can be different than the first stiffness. The second layer  120  can be constructed from any suitable polymer, such as, for example, a heat seal-coated (HSC) material, a polyethylene material, a polyvinyl chloride (PVC) material, a polyamide material, a polyester-based material, or any combination of such materials, including laminates constructed from multiple different materials. The second layer  120  can have any suitable thickness to provide the desired strength, flexibility, and sealing characteristics. For example, in some embodiments, the second layer  120  can be between about 50 microns (0.050 mm) and about 200 microns (0.200 mm). In other embodiments, the second layer  120  can be between about 50 microns (0.050 mm) and about 100 microns (0.100 mm). 
     The materials from which the first layer  110  and the second layer  120  are constructed are selected to ensure that the two layers can be joined to hermetically seal the storage volume  106  within which the tissue graft G is stored while also retaining the desired flexibility. Specifically, as shown, the two layers are joined at the second end portion  102  with the port  150  therebetween, and the two side edges  103  are joined together. The two layers can be joined together at the second end portion  102  and along the side edges  103  by any suitable mechanism, such as, for example, by heat bonding or by an adhesive. As shown in  FIG.  3   , the edge  111  of the first layer  110  and the edge  121  of the second layer  120  are configured to be joined together after the tissue graft G is loaded into the storage volume  106  to form a peelable seal  114  that hermetically seals the storage volume  106 . The peelable seal  114  can be configured to have any suitable failure (or peel) mechanism, and can be of any suitable peel strength. For example, in some embodiments, the peelable seal  114  can be an adhesive-based seal in which an adhesive layer pulls back from one of the first layer  110  or the second layer  120  when the first layer  110  is peeled apart from the second layer  120 . In other embodiments, the peelable seal  114  can be a cohesive seal in which an adhesive layer or intermediate layer fails within itself when the first layer  110  is peeled apart from the second layer  120 . The peelable seal  114  can be produced by any suitable mechanism as described herein, such as, for example, by a heat sealing operation. 
     By including the peelable seal  114 , the container assembly  100  reduces or eliminates the production of particulate matter or other debris that may result from cutting or tearing the flexible container  105  to extract the tissue specimen G. Moreover, the peelable seal  114  can facilitate opening the container assembly  100  in a predetermined fashion and/or in a predetermined direction (e.g., from the first end portion  101  towards the second end portion  102 ). The inclusion of the peelable seal  114  also eliminates the need for extra tools for opening the container assembly  100  during use. 
     The peelable seal  114  can be of any suitable geometry to facilitate the desired peel direction, peel strength, and the like. For example, in some embodiments, the peelable seal  114  can be an angled seal that provides for peel tabs  119  that can be grasped by the user to peel the first layer  110  from the second layer. Similarly stated, in some embodiments, the peelable seal  114  can be a chevron seal having any suitable angle. 
     As described above, the port  150  is coupled to the second end portion  102  of the container assembly  100  and is configured to allow fluid communication (as shown by the arrow BB in  FIG.  3   ) between a volume outside of the container assembly  100  and the storage volume  106 . Thus, the port  150  can be used to provide access to the storage volume  106  and the tissue specimen G after the first end portion  101  has been sealed closed. In this manner, the tissue specimen G can be treated with a preservation fluid or other material after being sealed into the container assembly  100 . The port  150  can also be coupled to a vacuum source to evacuate the storage volume for storage of the tissue specimen G. Moreover, during a surgical procedure, the port  150  can allow for inflow of rehydration fluid. 
     The port  150  can be any suitable port that selectively provides fluid communication to the storage volume  106 . For example, the port  150  can include a tube  151 , a valve, and/or a cap  153 . In some embodiments, the port  150  can be a needle-free port. In some embodiments, the port  150  can be a swabable connector. Similarly stated in some embodiments, the port  150  can have external surfaces and can be devoid of recesses or crevices such that the port  150  can be easily wiped or “swabbed” to maintain sterility during use. In some embodiments, the port  150  can include any of the barbed, swabable valves produced by the Halkey-Roberts Corporation, such as the  2455  series of swabable valves. 
     Although the port  150  is shown as being coupled at the second end portion  102  of the flexible container  105 , in other embodiments, the port  150  (and any of the ports described herein) can be coupled at any location and to any portion of the flexible container  105 . For example, in some embodiments, the port  150  (and any of the ports described herein) need not be coupled to an end of the container that is opposite from the end of the container that includes the peelable seal. Similarly, although the port  150  is shown as being aligned with the longitudinal axis A L  of the flexible container  105 , in other embodiments, the port  150  (and any of the ports described herein) can be offset from a center line of the flexible container. For example, in some embodiments, the port can be located at a corner of the flexible container. Moreover, the in some embodiments, the port  150  (and any of the ports described herein) can be coupled in a central portion of the flexible container. 
     The support structure  160  is configured to support the tissue specimen within the storage volume  106 . In this manner, the flexible container  105  can be sufficiently flexible to allow inflow and outflow of fluids, vacuum packaging, and rehydration, while the support structure  160  can provide the desired support to limit damage to the tissue specimen G during storage, rehydration, and removal for use in a surgical procedure. The support structure  160  can be constructed of any suitable material, and has a third stiffness that is greater than both the first stiffness (of the first layer  110 ) and the second stiffness (of the second layer  120 ). In this manner, the support structure  160  functions as a rigid structure (relative to the flexible container  105 ) that can support the tissue specimen G during loading into the tissue container  105 , storage within the tissue container  105 , and subsequent rehydration and preparation for use in a surgical procedure. For example, in some embodiments, the third stiffness is at least two times greater than the first stiffness and the second stiffness. In other embodiments, the third stiffness is at least five times greater than the first stiffness and the second stiffness. 
     The higher stiffness of the support structure  160  can be related to any of the thickness of the support structure  160 , the geometry (i.e., the cross-sectional geometry) of the support structure  160 , and the material from which the support structure  160  is constructed. In some embodiments, the support structure  160  can be thicker than either the first layer  110  or the second layer  120 . Specifically, in some embodiments, the support structure  160  can be at least twice as thick as either the first layer  110  or the second layer  120 . In other embodiments, the support structure  160  can be at least three times as thick as either the first layer  110  or the second layer  120 . Moreover, the support structure  160  can be constructed from any suitable polymer, such as, for example, a polyethylene terephthalate (PET) material, a polyethylene material, a polyvinyl chloride (PVC) material, a polyamide material, a polyester-based material, or any combination of such materials, including laminates constructed from multiple different materials. In some embodiments, the support structure  160  can be constructed from a different material than that from which the first layer  110  and/or the second layer  120  are constructed. 
     Although support structure  160  is shown as being a flat (or planar) structure, in other embodiments, the support structure  160  (and any of the support structures described herein) can be a tray-shaped structure that includes side edges. For example, in some embodiments, any of the container assemblies described herein can include the support structure  460  described herein. 
     In some embodiments, the container assembly  100  can be used to store the tissue specimen G for later use. For example,  FIG.  5    is a flow chart showing a method  10  of preparing a tissue specimen G for storage according to an embodiment. Although the method  10  is described with reference to the container assembly  100  shown in  FIGS.  1 - 4   , the method  10  can be performed with any of the container assemblies described herein. As shown in  FIG.  2   , the method  10  optionally includes placing the tissue specimen G on the support structure  160 , at  12 . The tissue specimen G (and in some cases, the tissue specimen G preloaded onto the support structure  160 ) is then inserted into the storage volume  106  of the flexible container  105 , at  14 . Specifically, as shown in  FIG.  2   , the tissue specimen G can be inserted through the opening  107 , as shown by the arrow AA. The tissue specimen G can then be positioned within the storage volume  106  between the first layer  110  and the support structure  160 , at  16 . Said another way, the tissue specimen G can be positioned on top of the support structure  160  and beneath the first layer  110 . 
     After the tissue specimen G is within the storage volume  106 , the edge  111  of the first layer  110  is then coupled to the edge  121  of the second layer  120  to form the peelable seal  114 , at  18  (see also  FIG.  3   ). As described above, the peelable seal  114  hermetically seals the storage volume  106  and is configured such that the first layer  110  can be peeled away from the second layer  120  to expose the storage volume  106 . The peelable seal  114  can be formed by any suitable mechanism. For example, in some embodiments, the peelable seal  114  can be formed by a heat sealer that applies a predetermined pressure and temperature to a portion of the edges  111 ,  121 . 
     After the tissue specimen G is sealed within the storage volume  106 , the port  150  can be used to further prepare the tissue specimen G and/or the entire container assembly  100  for storage. For example, in some embodiment, the method  10  optionally includes conveying a preservation fluid into the storage volume via the port  150 , at  19 . In other embodiments, the method optionally includes evacuating air and/or other fluids from the storage volume  106  via the port  150 . The support structure  160  provides the desired support for the tissue specimen G during the loading, preparation and/or storage process. 
     In some embodiments, the container assembly  100  can be used to rehydrate or otherwise prepare the tissue specimen G for use in a procedure. For example,  FIG.  6    is a flow chart showing a method  20  of rehydrating a tissue specimen G for use in a procedure, according to an embodiment. Although the method  20  is described with reference to the container assembly  100  shown in  FIGS.  1 - 4   , the method  20  can be performed with any of the container assemblies described herein. As shown by the arrow BB in  FIG.  3   , the method  20  includes conveying a rehydration fluid into the storage volume  106  via the port  150  coupled to the flexible container, at  22 . The hydration fluid can be saline solution, blood or any other suitable hydration fluid, and can be conveyed into the storage volume  106  at any suitable pressure. 
     The rehydration fluid is then maintained within the storage volume  106  to sufficiently rehydrate the tissue graft G, at  24 . Because the tissue graft G is sealed within the flexible container, there is no need to manipulate the tissue specimen G to ensure that the tissue specimen remains submerged or fully immersed within the rehydration fluid. Rather, the desired amount of rehydration fluid can be conveyed into the storage volume  106  to ensure that the tissue specimen G is fully immersed. Moreover, the container assembly  100  including the tissue graft G can be rotated (e.g., turned upside down) and gently manipulated to facilitate a thorough and rapid rehydration. During such manipulation, the support structure  160  provides support for the tissue graft G. In some embodiments, the method can include applying a vacuum via the port  150  to perform a vacuum rehydration procedure, at  26 . 
     After the tissue specimen G is sufficiently rehydrated, the first layer  110  is then peeled from the second layer  120  to expose the storage volume  106  (and the tissue specimen G therein), at  28 . This is shown in  FIG.  4    by the arrow CC. The rehydrated tissue specimen G can then be removed from the storage volume, at  29 . In some embodiments, the rehydrated tissue can be removed along with the support structure. 
       FIGS.  7 - 11    are various views of a container assembly  200  according to an embodiment. The container assembly  200  (and any of the container assemblies described herein) can be used to perform any of the methods described herein, such as the method  10  of preparing a tissue specimen for storage (see  FIG.  5   ) and/or the method  20  of rehydrating a tissue specimen for use in a procedure according to an embodiment (see  FIG.  6   ). As described herein, the container assembly  200  provides a single container that can be used for both storage and rehydration. The container provides sufficient support for the tissue specimen or graft G, which can be very fragile during and after rehydration. As shown, the container assembly  200  includes a flexible container  205 , a port  250  coupled to the flexible container  205 , and a support structure  260 . 
     The flexible container  205  includes a first end portion  201 , a second end portion  202 , and a pair of side edges  203  between the first end portion  201  and the second end portion  202 . The flexible container  205  defines a longitudinal axis A L  that extends longitudinally from the first end portion  201  and the second end portion  202 . The flexible container  205  is constructed from a first layer  210  and a second layer  220  coupled together to define a storage volume  206 . As shown in the side view of  FIG.  8   , when the container assembly  200  is in the first (or opened) configuration, an edge  211  of the first layer  210  is spaced apart from an edge  221  of the second layer  220  to define an opening  207  into the storage volume  206 . The opening  207  can be of any suitable size to facilitate loading of the support structure  260  and the tissue specimen G, as described herein. For example, although the opening  207  is shown as extending across the full length of the first end portion  201  of the flexible container  205 , in other embodiments, the opening  207  can extend across only a portion of the length of an end or a side of the flexible container  205 . 
     The first layer  210  can be constructed of any suitable material, and has a first stiffness. For example, in some embodiments, the first layer  210  can be a thin, peelable film, such as, for example, a heat seal-coated (HSC) material, a polyethylene material, a polyvinyl chloride (PVC) material, a polyamide material, a polyester-based material, or any combination of such materials, including laminates constructed from multiple different materials. For example, in some embodiments, the first layer  210  is a laminate that includes a substrate, a barrier coating, and an adhesive. The substrate can be, for example, a peelable film of the types (and thicknesses) described herein. The barrier coating can be any suitable coating, such as an aluminum oxide barrier coating of any suitable thickness (36 gauge, 40 gauge, 48 gauge, or any thickness therebetween). The adhesive can be any suitable adhesive that facilitates bonding of the first layer  210  to the second layer  220 . Moreover, the first layer  210  can have any suitable thickness to provide the desired strength, flexibility, and sealing characteristics. For example, in some embodiments, the first layer  210  can be between about 50 microns (0.050 mm) and about 200 microns (0.200 mm). In other embodiments, the first layer can be between about 50 microns (0.050 mm) and about 100 microns (0.100 mm). 
     The second layer  220  can be constructed of any suitable material, and has a second stiffness. For example, in some embodiments, the second layer  220  can constructed from the same material and/or can have the same stiffness as the first layer  210 . In other embodiments, the second layer  220  can be constructed from a different material and the second stiffness can be different than the first stiffness. The second layer  220  can be constructed from any suitable polymer, such as, for example, a heat seal-coated (HSC) material, a polyethylene material, a polyvinyl chloride (PVC) material, a polyamide material, a polyester-based material, or any combination of such materials, including laminates constructed from multiple different materials. For example, in some embodiments, the second layer  220  is a laminate that includes a substrate, a barrier coating, and an adhesive. The substrate can be constructed from any of the materials described herein. The barrier coating can be any suitable coating, such as an aluminum oxide barrier coating of any suitable thickness (36 gauge, 40 gauge, 48 gauge, or any thickness therebetween). The adhesive can be any suitable adhesive that facilitates bonding of the first layer  210  to the second layer  220 . Moreover, the second layer  220  can have any suitable thickness to provide the desired strength, flexibility, and sealing characteristics. For example, in some embodiments, the second layer  220  can be between about 50 microns (0.050 mm) and about 200 microns (0.200 mm). In other embodiments, the second layer  220  can be between about 50 microns (0.050 mm) and about 100 microns (0.100 mm). 
     The materials from which the first layer  210  and the second layer  220  are constructed are selected to ensure that the two layers can be joined to hermetically seal the storage volume  206  within which the tissue graft G is stored while also retaining the desired flexibility. Specifically, as shown, the two layers are joined at the second end portion  202  with the port  250  therebetween, and the two side edges  203  are joined together. The two layers can be joined together at the second end portion  202  and along the side edges  203  by any suitable mechanism, such as, for example, by heat bonding or by an adhesive. As shown in  FIG.  11   , the edge  211  of the first layer  210  and the edge  221  of the second layer  220  are configured to be joined together after the tissue graft G is loaded into the storage volume  206  to form a peelable seal  214  that hermetically seals the storage volume  206 . The peelable seal  214  can be configured to have any suitable failure (or peel) mechanism as described herein, and can be of any suitable peel strength. The peelable seal  214  can be produced by any suitable mechanism as described herein, such as, for example, by a heat sealing operation. 
     By including the peelable seal  214 , the container assembly  200  reduces or eliminates the production of particulate matter or other debris that may result from cutting or tearing the flexible container  205  to extract the tissue specimen G. Moreover, the peelable seal  214  can facilitate opening the container assembly  200  in a predetermined fashion and/or in a predetermined direction (e.g., from the first end portion  201  towards the second end portion  202 ). The inclusion of the peelable seal  214  also eliminates the need for extra tools for opening the container assembly  200  during use. 
     The peelable seal  214  can be of any suitable geometry to facilitate the desired peel direction, peel strength, and the like. For example, in some embodiments, the peelable seal  214  can be an angled seal that provides for peel tabs that can be grasped by the user to peel the first layer  210  from the second layer. Similarly stated, in some embodiments, the peelable seal  214  can be a chevron seal having any suitable angle. 
     As described above, the port  250  is coupled to the second end portion  202  of the container assembly  200  and is configured to allow fluid communication between a volume outside of the container assembly  200  and the storage volume  206 . Thus, the port  250  can be used to provide access to the storage volume  206  and the tissue specimen G after the first end portion  201  has been sealed closed. In this manner, the tissue specimen G can be treated with a preservation fluid or other material after being sealed into the container assembly  200 . The port  250  can also be coupled to a vacuum source to evacuate the storage volume for storage of the tissue specimen G. Moreover, during a surgical procedure, the port  250  can allow for inflow of rehydration fluid. 
     The port  250  can be any suitable port that selectively provides fluid communication to the storage volume  206 . For example, the port  250  can include a tube  251 , a valve  252 , and/or a cap  253 . In some embodiments, the port  250  can be a needle-free port. In some embodiments, the port  250  can be a swabable connector. Similarly stated in some embodiments, the port  250  can have external surfaces and can be devoid of recesses or crevices such that the port  250  can be easily wiped or “swabbed” to maintain sterility during use. In some embodiments, the port  250  can include any of the barbed, swabable valves produced by the Halkey-Roberts Corporation, such as the  2455  series of swabable valves. 
     The support structure  260  includes a first end  261  and a second end  262 , and is configured to support the tissue specimen within the storage volume  206 . In this manner, the flexible container  205  can be sufficiently flexible to allow inflow and outflow of fluids, vacuum packaging, and rehydration, while the support structure  260  can provide the desired support to limit damage to the tissue specimen G during storage, rehydration, and removal for use in a surgical procedure. The support structure  260  can be constructed of any suitable material, and has a third stiffness that is greater than both the first stiffness (of the first layer  210 ) and the second stiffness (of the second layer  220 ). In this manner, the support structure  260  functions as a rigid structure (relative to the flexible container  205 ) that can support the tissue specimen G during loading into the tissue container  205 , storage within the tissue container  205 , and subsequent rehydration and preparation for use in a surgical procedure. For example, in some embodiments, the third stiffness is at least two times greater than the first stiffness and the second stiffness. In other embodiments, the third stiffness is at least five times greater than the first stiffness and the second stiffness. 
     The higher stiffness of the support structure  260  can be related to any of the thickness of the support structure  260 , the geometry (i.e., the cross-sectional geometry) of the support structure  260 , and the material from which the support structure  260  is constructed. In some embodiments, the support structure  260  can be thicker than either the first layer  210  or the second layer  220 . Specifically, in some embodiments, the support structure  260  can be at least twice as thick as either the first layer  210  or the second layer  220 . In other embodiments, the support structure  260  can be at least three times as thick as either the first layer  210  or the second layer  220 . Moreover, the support structure  260  can be constructed from any suitable polymer, such as, for example, a polyethylene terephthalate (PET) material, a polyethylene material, a polyvinyl chloride (PVC) material, a polyamide material, a polyester-based material, or any combination of such materials, including laminates constructed from multiple different materials. In some embodiments, the support structure  260  can be constructed from a different material than that from which the first layer  210  and/or the second layer  220  are constructed. 
     Although support structure  260  is shown as being a flat (or planar) structure, in other embodiments, the support structure  260  (and any of the support structures described herein) can be a tray-shaped structure that includes side edges. For example, in some embodiments, any of the container assemblies described herein can include the support structure  460  described herein. 
     Although the flexible container  205  is shown as having the opening  207  and the peelable seal  214  being at the first end portion  201  of the container opposite from the second end portion  202  at which the port  250  is located, in other embodiments, the port  250  and the peelable seal (and “loading” opening) can be at any portion of the flexible container. For example,  FIGS.  12 - 15    are various views of a container assembly  300  according to an embodiment that includes a “side opening” configuration. The container assembly  300  (and any of the container assemblies described herein) can be used to perform any of the methods described herein, such as the method  10  of preparing a tissue specimen for storage (see  FIG.  5   ) and/or the method  20  of rehydrating a tissue specimen for use in a procedure according to an embodiment (see  FIG.  6   ). As described herein, the container assembly  300  provides a single container that can be used for both storage and rehydration. The container provides sufficient support for the tissue specimen or graft G, which can be very fragile during and after rehydration. As shown, the container assembly  300  includes a flexible container  305 , a port  350  coupled to the flexible container  305 , and a support structure  360 . 
     The flexible container  305  includes a first end portion  301 , a second end portion  302 , and a pair of side edges  303 A and  303 B between the first end portion  301  and the second end portion  302 . The flexible container  305  defines a longitudinal axis A L  that extends longitudinally from the first end portion  301  and the second end portion  302 . The flexible container  305  is constructed from a first layer  310  and a second layer  320  coupled together to define a storage volume  306 . As shown in the side view of  FIG.  13    and in contrast to the flexible container  205 , when the container assembly  300  is in the first (or opened) configuration, the end edge  311  of the first layer  310  is coupled to the corresponding end edge  321  of the second layer  320  to seal the first end portion  301  of the container. Instead, a side edge  313  of the first layer  310  is spaced apart from the corresponding side edge  323  of the second layer  320  to define a side opening  307  (along the side edge  303 B of the container) into the storage volume  306 . The opening  307  can be of any suitable size to facilitate loading of the support structure  360  and the tissue specimen G, as described herein. 
     The first layer  310  can be constructed of any suitable material, and has a first stiffness. For example, in some embodiments, the first layer  310  can be a thin, peelable film, such as, for example, a heat seal-coated (HSC) material, a polyethylene material, a polyvinyl chloride (PVC) material, a polyamide material, a polyester-based material, or any combination of such materials, including laminates constructed from multiple different materials. For example, in some embodiments, the first layer  310  is a laminate that includes a substrate, a barrier coating, and an adhesive. The substrate can be, for example, a peelable film of the types (and thicknesses) described herein. The barrier coating can be any suitable coating, such as an aluminum oxide barrier coating of any suitable thickness (36 gauge, 40 gauge, 48 gauge, or any thickness therebetween). The adhesive can be any suitable adhesive that facilitates bonding of the first layer  310  to the second layer  320 . Moreover, the first layer  310  can have any suitable thickness to provide the desired strength, flexibility, and sealing characteristics. For example, in some embodiments, the first layer  310  can be between about 50 microns (0.050 mm) and about 200 microns (0.200 mm). In other embodiments, the first layer can be between about 50 microns (0.050 mm) and about 100 microns (0.100 mm). 
     The second layer  320  can be constructed of any suitable material, and has a second stiffness. For example, in some embodiments, the second layer  320  can constructed from the same material and/or can have the same stiffness as the first layer  310 . In other embodiments, the second layer  320  can be constructed from a different material and the second stiffness can be different than the first stiffness. The second layer  320  can be constructed from any suitable polymer, such as, for example, a heat seal-coated (HSC) material, a polyethylene material, a polyvinyl chloride (PVC) material, a polyamide material, a polyester-based material, or any combination of such materials, including laminates constructed from multiple different materials. For example, in some embodiments, the second layer  320  is a laminate that includes a substrate, a barrier coating, and an adhesive. The substrate can be constructed from any of the materials described herein. The barrier coating can be any suitable coating, such as an aluminum oxide barrier coating of any suitable thickness (36 gauge, 40 gauge, 48 gauge, or any thickness therebetween). The adhesive can be any suitable adhesive that facilitates bonding of the first layer  310  to the second layer  320 . Moreover, the second layer  320  can have any suitable thickness to provide the desired strength, flexibility, and sealing characteristics. For example, in some embodiments, the second layer  320  can be between about 50 microns (0.050 mm) and about 200 microns (0.200 mm). In other embodiments, the second layer  320  can be between about 50 microns (0.050 mm) and about 100 microns (0.100 mm). 
     The materials from which the first layer  310  and the second layer  320  are constructed are selected to ensure that the two layers can be joined to hermetically seal the storage volume  306  within which the tissue graft G is stored while also retaining the desired flexibility. Specifically, as shown, the two layers are joined at the first end portion  301  and at the second end portion  302  with the port  350  therebetween. The first side edge  303 A is also joined together, leaving the opening  307  along the second side edge  303 B. The two layers can be joined together at the second end portion  302  and along the side edges  303  by any suitable mechanism, such as, for example, by heat bonding or by an adhesive. As shown in  FIG.  15   , the edge  311  of the first layer  310  and the edge  321  of the second layer  320  are configured to be joined together after the tissue graft G is loaded into the storage volume  306  to form a peelable seal  314  that hermetically seals the storage volume  306 . The peelable seal  314  can be configured to have any suitable failure (or peel) mechanism as described herein, and can be of any suitable peel strength. The peelable seal  314  can be produced by any suitable mechanism as described herein, such as, for example, by a heat sealing operation. 
     The peelable seal  314  can be of any suitable geometry to facilitate the desired peel direction, peel strength, and the like. For example, in some embodiments, the peelable seal  314  can be an angled seal that provides for peel tabs that can be grasped by the user to peel the first layer  310  from the second layer. Similarly stated, in some embodiments, the peelable seal  314  can be a chevron seal having any suitable angle. 
     As described above, the port  350  is coupled to the second end portion  302  of the container assembly  300  and is configured to allow fluid communication between a volume outside of the container assembly  300  and the storage volume  306 . Thus, the port  350  can be used to provide access to the storage volume  306  and the tissue specimen G after the first end portion  301  has been sealed closed. In this manner, the tissue specimen G can be treated with a preservation fluid or other material after being sealed into the container assembly  300 . The port  350  can also be coupled to a vacuum source to evacuate the storage volume for storage of the tissue specimen G. Moreover, during a surgical procedure, the port  350  can allow for inflow of rehydration fluid. The port  350  can be any suitable port that selectively provides fluid communication to the storage volume  306 , such as the port  250  described above. The port  350  can include a tube  351 , a valve  352 , and/or a cap  353 . 
     The support structure  360  includes a first end  361  and a second end  362 , and is configured to support the tissue specimen within the storage volume  306 . In this manner, the flexible container  305  can be sufficiently flexible to allow inflow and outflow of fluids, vacuum packaging, and rehydration, while the support structure  360  can provide the desired support to limit damage to the tissue specimen G during storage, rehydration, and removal for use in a surgical procedure. The support structure  360  can be constructed of any suitable material, and has a third stiffness that is greater than both the first stiffness (of the first layer  310 ) and the second stiffness (of the second layer  320 ). In this manner, the support structure  360  functions as a rigid structure (relative to the flexible container  305 ) that can support the tissue specimen G during loading into the tissue container  305 , storage within the tissue container  305 , and subsequent rehydration and preparation for use in a surgical procedure. For example, in some embodiments, the third stiffness is at least two times greater than the first stiffness and the second stiffness. In other embodiments, the third stiffness is at least five times greater than the first stiffness and the second stiffness. 
     The higher stiffness of the support structure  360  can be related to any of the thickness of the support structure  360 , the geometry (i.e., the cross-sectional geometry) of the support structure  360 , and the material from which the support structure  360  is constructed. In some embodiments, the support structure  360  can be thicker than either the first layer  310  or the second layer  320 . Specifically, in some embodiments, the support structure  360  can be at least twice as thick as either the first layer  310  or the second layer  320 . In other embodiments, the support structure  360  can be at least three times as thick as either the first layer  310  or the second layer  320 . Moreover, the support structure  360  can be constructed from any suitable polymer, such as, for example, a polyethylene terephthalate (PET) material, a polyethylene material, a polyvinyl chloride (PVC) material, a polyamide material, a polyester-based material, or any combination of such materials, including laminates constructed from multiple different materials. In some embodiments, the support structure  360  can be constructed from a different material than that from which the first layer  310  and/or the second layer  320  are constructed. 
     Although support structure  360  is shown as being a flat (or planar) structure, in other embodiments, the support structure  360  (and any of the support structures described herein) can be a tray-shaped structure that includes side edges. For example, in some embodiments, any of the container assemblies described herein can include the support structure  460  shown in  FIGS.  16  and  17   . The support structure  460  includes a first end portion  461 , a second end portion  462 , a bottom surface  464  and a raised side edge  463 . The support structure  460  can be removably disposed within a flexible container, such as the flexible containers  205  and  305 , and is configured to support a tissue specimen within the storage volume of the flexible container. In this manner, the support structure  460  can provide the desired support to limit damage to the tissue specimen (not shown in  FIGS.  16  and  17   ) during storage, rehydration, and removal for use in a surgical procedure. Specifically, the tissue specimen can be placed on the bottom surface  464  and can be surrounded by raised side edge  463 . The side edge  463  can reduce the likelihood that the tissue specimen will slide off the bottom surface  464  when the support member is being moved (e.g., to load the tissue container for storage or to remove the tissue specimen for use in a procedure). The side edge  463  also increases the cross-sectional area moment of inertia of the support structure  460  (as compared to that for a planar support structure), thereby increasing the stiffness of the support structure. Although the side edge  463  is shown as surrounding the entire perimeter of the bottom surface  464 , in other embodiments a support structure can include an edge that only partially surrounds the bottom surface. 
     In addition to the side edge  463 , the first end portion  461  of the support structure  460  also includes a tab  469 . The tab  469  can be used to manipulate the support structure  460  during loading of the container, unloading of the container, or the like. In some embodiments, the tab  469  (or any other portion of the support structure  460 ) can include a label or indicium associated with the tissue specimen. In some embodiments, the label can be a machine-readable (and/or machine writable) label, such as a bar code, RFID, QR code, or the like. This arrangement can facilitate identification and tracking of the tissue specimen within the support structure  460  and/or the associated flexible container. 
     The support structure  460  can be constructed of any suitable material, and, in some embodiments, has a third stiffness that is greater than the stiffness of the flexible container within which the support structure is disposed. In this manner, the support structure  460  functions as a rigid structure (relative to the flexible container  405 ) that can support the tissue specimen during loading into the tissue container  405 , storage within the tissue container  405 , and subsequent rehydration and preparation for use in a surgical procedure. The support structure  460  can be constructed from any suitable polymer, such as, for example, a polyethylene terephthalate (PET) material, a polyethylene material, a polyvinyl chloride (PVC) material, a polyamide material, a polyester-based material, or any combination of such materials, including laminates constructed from multiple different materials. In some embodiments, the support structure  460  can be constructed from a different material than that from which the first layer  410  and/or the second layer  420  are constructed. 
     In some embodiments, any of the support structures disclosed herein can include one or more holes, channels, or grooves to facilitate rehydration. For example, in some embodiments, any of the support structures can define a series of through holes, like those shown in the support structure  560  shown in  FIG.  18   . The support structure  560  includes a first end  561 , a second end  562 , and a bottom surface  564 . The support structure  560  can be removably disposed within a flexible container, such as the flexible containers  205  and  305 , and is configured to support a tissue specimen within the storage volume of the flexible container. In this manner, the support structure  560  can provide the desired support to limit damage to the tissue specimen (not shown in  FIG.  18   ) during storage, rehydration, and removal for use in a surgical procedure. As shown, the bottom surface  564  defines a series of holes  565  through which fluid can pass. In this manner, the side of the tissue specimen facing the bottom surface  564  can receive and/or be exposed to rehydration fluid when such fluid is conveyed into the flexible container (e.g., via any of the ports as described herein). In other embodiments, a support structure need not include holes or openings therethrough, but rather can include one or more channels or grooves through which the rehydration fluid can flow to reach the bottom side of the tissue specimen. 
     Although the container assembly  200  is shown and described as including a support structure that is removably disposed within the flexible container  205 , in other embodiments, a container assembly can include a support structure that is fixedly coupled to the flexible container. Similarly stated, in some embodiments a container assembly can include a support structure that is captive with (or is non-removable from) the flexible container. In some embodiments, for example, the support structure (such as the support structure  260 ) can be bonded or attached to the one of the layers of the flexible container (e.g., the second layer  220 ). In other embodiments, a flexible container can define a captive pocket (or volume) within which the support structure is sealed. For example,  FIGS.  19 - 22    show various views of a container assembly  600  according to an embodiment that includes a three-layer design with a captive support structure  660 . The container assembly  600  (and any of the container assemblies described herein) can be used to perform any of the methods described herein, such as the method  10  of preparing a tissue specimen for storage (see  FIG.  5   ) and/or the method  20  of rehydrating a tissue specimen for use in a procedure according to an embodiment (see  FIG.  6   ). As described herein, the container assembly  600  provides a single container that can be used for both storage and rehydration. The container provides sufficient support for the tissue specimen or graft G, which can be very fragile during and after rehydration. As shown, the container assembly  600  includes a flexible container  605 , a port  650  coupled to the flexible container  605 , and a support structure  660 . 
     The flexible container  605  includes a first end portion  601 , a second end portion  602 , and a pair of side edges  603  between the first end portion  601  and the second end portion  602 . The flexible container  605  is constructed from a first layer  610 , a second layer  620 , and a third layer  630 . The first layer  610  and the second layer  620  are coupled together to define a storage volume  606  within which the tissue specimen G can be contained. As shown in the side view of  FIG.  19    when the container assembly  600  is in the first (or opened) configuration, an edge  611  of the first layer  610  is spaced apart from an edge  621  of the second layer  620  to define an opening  607  into the storage volume  606 . The opening  607  can be of any suitable size to facilitate loading of the support structure  660  and the tissue specimen G, as described herein. 
     The second layer  620  and the third layer  630  are coupled together to define a support volume  634  within which the support structure  660  is sealed. In this manner, the support structure  660  is captive within the flexible container  605 , and can be maintained in the desired position relative to the storage volume  606  and/or the tissue specimen G. As shown in the side views of  FIGS.  19  and  22   , an edge  631  of the third layer  630  is sealed to (or joined with) the edge  621  of the second layer  620  to enclose the support volume  634 . The third layer  630  and the second layer  620  can be joined together at the first end portion  601  by any suitable mechanism, such as, for example, by heat bonding or by an adhesive. Although the edge  621  is shown as being between the edge  611  and the edge  631 , in other embodiments, the third layer  630  can be sealed to the second layer  620  at any suitable location to enclose the support volume. 
     The first layer  610  can be constructed of any suitable material, and has a first stiffness. For example, in some embodiments, the first layer  610  can be a thin, peelable film, such as, for example, a heat seal-coated (HSC) material, a polyethylene material, a polyvinyl chloride (PVC) material, a polyamide material, a polyester-based material, or any combination of such materials, including laminates constructed from multiple different materials. For example, in some embodiments, the first layer  610  is a laminate that includes a substrate, a barrier coating, and an adhesive. The substrate can be, for example, a peelable film of the types (and thicknesses) described herein. The barrier coating can be any suitable coating, such as an aluminum oxide barrier coating of any suitable thickness (36 gauge, 40 gauge, 48 gauge, or any thickness therebetween). The adhesive can be any suitable adhesive that facilitates bonding of the first layer  610  to the second layer  620 . Moreover, the first layer  610  can have any suitable thickness to provide the desired strength, flexibility, and sealing characteristics. For example, in some embodiments, the first layer  610  can be between about 50 microns (0.050 mm) and about 200 microns (0.200 mm). In other embodiments, the first layer can be between about 50 microns (0.050 mm) and about 100 microns (0.100 mm). 
     The second layer  620  can be constructed of any suitable material, and has a second stiffness. Likewise, the third layer  630  can be constructed of any suitable material, and has a third stiffness. For example, in some embodiments, the second layer  620  and/or the third layer  630  can constructed from the same material and/or can have the same stiffness as the first layer  610 . In other embodiments, the second layer  620  and/or the third layer  630  can be constructed from a different material and the second stiffness and/or the third stiffness can be different than the first stiffness. The second layer  620  and/or the third layer  630  can be constructed from any suitable polymer, such as, for example, a heat seal-coated (HSC) material, a polyethylene material, a polyvinyl chloride (PVC) material, a polyamide material, a polyester-based material, or any combination of such materials, including laminates constructed from multiple different materials. For example, in some embodiments, the second layer  620  and/or the third layer  630  is a laminate that includes a substrate, a barrier coating, and an adhesive. The substrate can be constructed from any of the materials described herein. The barrier coating can be any suitable coating, such as an aluminum oxide barrier coating of any suitable thickness (36 gauge, 40 gauge, 48 gauge, or any thickness therebetween). The adhesive can be any suitable adhesive that facilitates bonding of the first layer  610  to the second layer  620 . Moreover, the second layer  620  and/or the third layer  630  can have any suitable thickness to provide the desired strength, flexibility, and sealing characteristics. For example, in some embodiments, the second layer  620  can be between about 50 microns (0.050 mm) and about 200 microns (0.200 mm). In other embodiments, the second layer  620  can be between about 50 microns (0.050 mm) and about 100 microns (0.100 mm). 
     The materials from which the first layer  610 , the second layer  620 , and the third layer  630  are constructed are selected to ensure that the three layers can be joined to hermetically seal the storage volume  606  within which the tissue graft G is stored (and the support volume  634  within which the support structure  660  is contained) while also retaining the desired flexibility. Specifically, as shown, the two three layers are joined at the first end portion  601  and at the second end portion  602  with the port  650  therebetween. As shown in  FIG.  22   , the edge  611  of the first layer  610  and the edge  621  of the second layer  620  are configured to be joined together after the tissue graft G is loaded into the storage volume  606  to form a peelable seal  614  that hermetically seals the storage volume  606 . The peelable seal  614  can be configured to have any suitable failure (or peel) mechanism as described herein, and can be of any suitable peel strength. The peelable seal  614  can be produced by any suitable mechanism as described herein, such as, for example, by a heat sealing operation. 
     As described above, the port  650  is coupled to the second end portion  602  of the container assembly  600  and is configured to allow fluid communication between a volume outside of the container assembly  600  and the storage volume  606 . Thus, the port  650  can be used to provide access to the storage volume  606  and the tissue specimen G after the first end portion  601  has been sealed closed. In this manner, the tissue specimen G can be treated with a preservation fluid or other material after being sealed into the container assembly  600 . The port  650  can also be coupled to a vacuum source to evacuate the storage volume for storage of the tissue specimen G. Moreover, during a surgical procedure, the port  650  can allow for inflow of rehydration fluid. The port  650  can be any suitable port that selectively provides fluid communication to the storage volume  606 , such as the port  250  described above. The port  650  can include a tube  651 , a valve, and/or a cap  653 . 
     The support structure  660  is configured to support the tissue specimen within the storage volume  606 . In this manner, the flexible container  605  can be sufficiently flexible to allow inflow and outflow of fluids, vacuum packaging, and rehydration, while the support structure  660  can provide the desired support to limit damage to the tissue specimen G during storage, rehydration, and removal for use in a surgical procedure. The support structure  660  can be constructed of any suitable material, and has a stiffness that is greater than the first stiffness (of the first layer  610 ), the second stiffness (of the second layer  620 ), and the third stiffness (of the third layer  630 ). In this manner, the support structure  660  functions as a rigid structure (relative to the flexible container  605 ) that can support the tissue specimen G during loading into the tissue container  605 , storage within the tissue container  605 , and subsequent rehydration and preparation for use in a surgical procedure. 
     The higher stiffness of the support structure  660  can be related to any of the thickness of the support structure  660 , the geometry (i.e., the cross-sectional geometry) of the support structure  660 , and the material from which the support structure  660  is constructed. In some embodiments, the support structure  660  can be thicker than the first layer  610 , the second layer  620 , or the third layer  630 . Specifically, in some embodiments, the support structure  660  can be at least twice as thick as either the first layer  610 , the second layer  620 , or the third layer  630 . In other embodiments, the support structure  660  can be at least three times as thick as either the first layer  610 , the second layer  620 , or the third layer  630 . Moreover, the support structure  660  can be constructed from any suitable polymer, such as, for example, a polyethylene terephthalate (PET) material, a polyethylene material, a polyvinyl chloride (PVC) material, a polyamide material, a polyester-based material, or any combination of such materials, including laminates constructed from multiple different materials. In some embodiments, the support structure  660  can be constructed from a different material than that from which the first layer  610 , the second layer  620  and/or the third layer  630  are constructed. 
       FIGS.  23 - 25    show various views of a container assembly  700  according to an embodiment that includes another three-layer design with a captive support structure  760 , according to an embodiment. The container assembly  700  (and any of the container assemblies described herein) can be used to perform any of the methods described herein, such as the method  10  of preparing a tissue specimen for storage (see  FIG.  5   ) and/or the method  20  of rehydrating a tissue specimen for use in a procedure according to an embodiment (see  FIG.  6   ). As described herein, the container assembly  700  provides a single container that can be used for both storage and rehydration. The container provides sufficient support for the tissue specimen or graft G, which can be very fragile during and after rehydration. The container assembly  700  is similar in many respects to the container assembly  600 , and includes a flexible container  705 , a port  750  coupled to the flexible container  705 , and a support structure  760 . 
     The flexible container  705  includes a first end portion  701 , a second end portion  702 , and a pair of side edges  703  between the first end portion  701  and the second end portion  702 . The flexible container  705  is constructed from a first layer  710 , a second layer  720 , and a third layer  730 . The first layer  710  and the second layer  720  are coupled together to define a storage volume  706  within which the tissue specimen G can be contained. When the container assembly  700  is in the first (or opened) configuration, an edge  711  of the first layer  710  is spaced apart from an edge  721  of the second layer  720  to define an opening (not shown) into the storage volume  706 . 
     The second layer  720  and the third layer  730  are coupled together to define a support volume  734  within which the support structure  760  is sealed. In this manner, the support structure  760  is captive within the flexible container  705 , and can be maintained in the desired position relative to the storage volume  706  and/or the tissue specimen G. An edge  731  of the third layer  730  is sealed to (or joined with) the edge  721  of the second layer  720  to enclose the support volume  734 . The third layer  730  and the second layer  720  can be joined together at the first end portion  701  by any suitable mechanism, such as, for example, by heat bonding or by an adhesive. 
     The first layer  710  can be constructed of any suitable material, and has a first stiffness, in a similar manner as that described above for the first layer  610 . The second layer  720  can be constructed of any suitable material, and has a second stiffness, in a similar manner as that described above for the second layer  620 . Likewise, the third layer  730  can be constructed of any suitable material, and has a third stiffness, in a similar manner as that described above for the third layer  630 . As shown in  FIG.  25   , the edge  711  of the first layer  710  and the edge  721  of the second layer  720  are configured to be joined together after the tissue graft G is loaded into the storage volume  706  to form a peelable seal  714  that hermetically seals the storage volume  706 . The peelable seal  714  can be configured to have any suitable failure (or peel) mechanism as described herein, and can be of any suitable peel strength. The peelable seal  714  can be produced by any suitable mechanism as described herein, such as, for example, by a heat sealing operation. 
     As described above, the port  750  is coupled to the second end portion  702  of the container assembly  700  and is configured to allow fluid communication between a volume outside of the container assembly  700  and the storage volume  706 . Thus, the port  750  can be used to provide access to the storage volume  706  and the tissue specimen G after the first end portion  701  has been sealed closed. The port  750  can be any suitable port that selectively provides fluid communication to the storage volume  706 , such as the port  250  described above. The port  750  can include a tube  751 , a valve, and/or a cap  753 . 
     The support structure  760  is configured to support the tissue specimen within the storage volume  706 . In this manner, the flexible container  705  can be sufficiently flexible to allow inflow and outflow of fluids, vacuum packaging, and rehydration, while the support structure  760  can provide the desired support to limit damage to the tissue specimen G during storage, rehydration, and removal for use in a surgical procedure. The support structure  760  can be constructed of any suitable material, as that described above for the support structure  660 . 
     While various embodiments have been described above, it should be understood that they have been presented by way of example only, and not limitation. Where methods and/or schematics described above indicate certain events and/or flow patterns occurring in certain order, the ordering of certain events and/or operations may be modified. While the embodiments have been particularly shown and described, it will be understood that various changes in form and details may be made. 
     Although various embodiments have been described as having particular features and/or combinations of components, other embodiments are possible having a combination of any features and/or components from any of embodiments as discussed above. Aspects have been described in the general context of medical devices, and more specifically tissue packaging devices, but inventive aspects are not necessarily limited to use in medical devices and tissue packaging.