Vial adapter for secure fluid transfer

Abstract

The disclosure relates to closed fluid transfer systems and their related components, and more particularly, to a vial adapter component providing improved seal between the adapter and the vial.

Description

VIAL ADAPTER FOR SECURE FLUID TRANSFERCROSS REFERENCE TO RELATED APPLICATIONS

[0001] The present application incorporates by reference co-owned US Patent No. 11,219,577, titled Closed Fluid Transfer System in its entirety.BACKGROUND

[0002] The present disclosure is directed to closed fluid transfer devices (CFTD) and their related components, and more particularly, to a vial adapter component providing improved seal between the adapter and the vial, by incorporating a stand-alone, independent sealing interface.

[0003] Cytotoxic drugs, commonly used in cancer treatment, pose significant risks not only to patients but also to healthcare providers due to potential exposure during drug preparation and administration. Even small, chronic exposures can lead to serious health issues for providers and technicians. The current system of delivering these drugs can involve injecting liquids into sealed vials, thereby increasing pressure and potentially causing hazardous drug molecules to escape, particularly during needle withdrawal.

[0004] The current, typical sealing interface is comprised of forming a self-centering vial adapter where the sole sealing mechanism is between the spike (needle) of the vial adaptor and the vial septum.

[0005] Consequently, the variability in shapes, sizes and shoulder tapering of the various vials containing the types of medication requiring secure liquid transfer, introduces an additional challenge (and significant risk) in instances of off-center or tilted needle penetration into vial stoppers during the preparation and administration using typical vial adaptors. These challenges / risks include, for example, an increased likelihood of leaks, where the compromised seal can allow hazardous drug vapors or liquids to escape, posing a serious exposure risk to healthcare providers and technicians. Likewise, misaligned needle (spike) penetration can also result in incomplete transfer of the medication through for example, backflow, which could lead to dosing errors (and air incorporation). Furthermore, improper needle entry can disrupt the pressure balance within the vial, making it difficult to draw up the medication or causing a vacuum effect that can result in spills and additional exposure risks. Moreover, repeated off-center puncturescan weaken the rubber stopper over time, compromising its ability to maintain sterility and increasing the risk of contamination.

[0006] Other factors that may affect the quality of seal between the medication and the environment, can be the resilience of the vial septum and the differences in diameter of the vial adaptor spike. These risks can manifest in vial adaptors equipped with a vial-centering mechanisms, that will stretch the septum in off-center penetration, potentially increasing the probability of incomplete seal and forming tears in the septum over time.

[0007] The proposed technology aims to address the shortcomings of the current components.SUMMARY

[0008] In an exemplary implementation, provided herein is a vial adapter component for a closed and secure fluid transfer having improved seal between the adapter and the vial, by providing a stand-alone sealing interface between the vial adaptor and the vial septum, that is independent of the vial adaptor spike acting as a redundancy mechanism.

[0009] In another exemplary implementation, provided herein is a vial adapter assembly for a closed fluid transfer from a vial, the vial comprising: a cylindrical body having a closed bottom and a collar extending from tapering shoulder terminating in an open circular lip, with an elastic stopper engaged within the open circular lip, and a cap partially covering the elastic stopper and coupled to the circular lip, wherein the vial adapter assembly comprising an clastic seal disc adapted, sized, and configured to transition from a first position wherein at least a lower surface of the elastic seal disc is not deformed, to a second position wherein the at least lower surface of the elastic seal disc is deformed, forming a sealing interface that is at least partially complimentary to the upper surface of the elastic stopper of the vial.

[0010] In yet another exemplary implementation, the vial adapter further comprises a hollow spike configured to penetrate the elastic stopper on the vial, and wherein the elastic seal disc having an upper surface and a lower surface, defining a coaxial aperture, is coupled to the spike.

[0011] In yet another exemplary implementation, the vial adapter assembly comprises: a vial adapter, comprising: a basin coupled to a semi toroid defining a basal portion of a hollow toroid, the basin having an outer annular rim and an inner annular rim, a basally tapering open cylinder extending basally from the inner annular rim comprising a plurality of resilient graspersconfigured to engage the circular’ lip of the vial, a cover defining the apical portion of the hollow toroid, defining an outer lip coupled to the outer annular rim of the semi-toroid, and an inner lip, wherein the hollow toroid defines an expansion chamber further accommodating a bladder, an apically tapering cylindrical adapter having a narrow proximal end operable to engage an open distal end of a syringe adapter, and a wide distal end coupled to the inner annular- rim of the semi-toroid, the wide distal end defining a basal surface, with a coaxial lumen extending therethrough, wherein the proximal end is in fluid communication with the coaxial lumen, the hollow spike extending distally from the basal surface of the wide distal end, the hollow spike comprises a first lumen being in fluid communication with the coaxial lumen of cylindrical adapter, and a second lumen being in fluid communication with the bladder in the expansion chamber, and a semi-toroid comprising a circular open channel defining an outer diameter and an inner diameter coupled to cover, together forming the hollow toroid coupled to the basin, with the apically tapering cylindrical adapter extending through the inner diameter of the semi toroid, wherein, upon engaging the vial, and penetrating the stopper with the spike, the seal disc is adapted, sized, and configured to transition from the first position wherein at least the lower surface of the elastic seal disc is not deformed, to the second position wherein the at least lower surface of the elastic seal disc is deformed, forming a sealing interface that is at least partially complimentary to the upper surface of the elastic stopper of the vial.

[0012] In an exemplary implementation, provided herein is a method of expanding, and providing an independent sealing surface between a vial adapter assembly and a vial, implemented in combination with the vial, the vial comprising a cylindrical body having a closed bottom and a collar extending from tapering shoulder terminating in an open circular lip, with an elastic stopper engaged within the open circular lip, wherein the vial adapter assembly comprises a seal disc adapted, sized, and configured to transition from a first position wherein at least a lower surface of the elastic seal disc is not deformed, to a second position wherein the at least lower surface of the elastic seal disc is deformed, forming a sealing interface that is at least partially complimentary to the upper surface of the elastic stopper of the vial, the method comprises: coupling the vial adapter to the vial, wherein the vial adapter is configured to perforate the elastic stopper of the vial, and causing the seal to transition from the first position having the at least a lower surface of the elastic seal disc that is not deformed (pristine), to the second position wherein the at least lower surface of the elastic seal disc is deformed, forming asealing interface that is at least partially complimentary to the upper surface of the elastic stopper of the vial, thereby expanding the sealing surface between the vial adapter and the vial.BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The vial adapter assembly for a closed and secure fluid transfer providing improved seal between the adapter and the vial, will become apparent from the following detailed description when read in conjunction with the figures, which are exemplary, not limiting, and in which:

[0014] FIG. 1A, is a bottom perspective view of an exemplary implementation of the vial adaptor coupled to the vial, with FIG. IB illustrating a cutaway representation of FIG. 1 A;

[0015] FIG. 2, is an enlargement of a section of the cutaway illustrated in FIG. IB;

[0016] FIG. 3 A, illustrates a top perspective view of an exemplary configuration of a vial used for secure fluid transfer, with FIG. 3B illustrating a side view thereof;

[0017] FIG. 4A, is an enlarged illustration of the cap and elastic seal disc following perforation of the elastic stopper with the spike of the vial adapter assembly using an exemplary implementation thereof, with FIG. 4B illustrating an exploded view showing the concave cross section of the elastic seal disc caused

[0018] FIG. 5 A showing the non-deformed elastic seal disc before coupling to the vial, while FIG. 5B is a further enlargement of inset A in FIG. 2, showing the deformed elastic seal disc;

[0019] FIG. 6, is an exploded view of an exemplary implementation of the vial adapter assembly; and

[0020] FIG. 7A, is an illustration of a bottom perspective view of a first exemplary implementation of the apically tapering cylindrical adapter enabling formation of a concave cross section of the elastic seal disc, with FIG. 7B showing an illustration of a bottom perspective view of another exemplary implementation of the apically tapering cylindrical adapter enabling formation of a concave cross section of the elastic seal disc illustrated in FIG. 7C.

[0021] While the disclosure of the vial adapter assembly disclosed herein, is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be further described in detail hereinbelow. It should be understood, however, that the intention is not to limit the disclosure to the exemplaryimplementations described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives.DETAILED DESCRIPTION

[0022] Provided herein are exemplary implementations of a vial adapter component for a closed and secure fluid transfer providing expanded and independent sealing interface between the contents of the vial and the environment.Definitions:

[0023] The term “coupled”, including its various forms such as “operably coupling”, "coupling" or "couplable", refers to and comprises any direct or indirect, structural coupling, connection or attachment, or adaptation or capability for such a direct or indirect structural or operational coupling, connection or attachment, including integrally formed components and components which are coupled via or through another component or by the forming process. Indirect coupling may involve coupling through an intermediary member or adhesive, or abutting and otherwise resting against, whether frictionally or by separate means without any physical connection.

[0024] In addition, for the purposes of the present disclosure, directional or positional terms such as “proximal”, “distal”, "top", "bottom", "upper," "lower," "side," "front," "frontal," "forward," "rear," "rearward," "back," "trailing," "above," "below," "left," "right," "radial "vertical," "upward," "downward," "outer," "inner," "exterior," "interior," "intermediate,", “apical”, “basal”, etc., are merely used for convenience in describing the various exemplary implementations of the present disclosure.

[0025] Likewise, the term "engage" and various forms thereof, when used with reference to an engaging element, for example in the engagement of lip 201 by plurality of resilient graspers 1125i (see e.g., FIG.s 5, and 6), the term refers in an exemplary implementation to the application of any forces that tend to hold the plurality of resilient graspers 1125i and vial lip 201 (and thereby vial 20) together against inadvertent or undesired separating forces (e.g., such as may be introduced during swiveling fluid transfer). It is to be understood, however, thatengagement does not in all cases require an interlocking connection that is maintained against every conceivable type or magnitude of separating force. Further, the term "engaging element" refers in another exemplary implementation to one or a plurality of coupled components, at least one (e.g., resilient graspers 1125i) of which is configured for releasably engaging another element (e.g., vial 20 circular lip 201). Thus, this term encompasses both single part engaging elements and multi-part-assemblies.

[0026] The terms “first,” “second,” and the like, herein do not denote any order, quantity, or importance, but rather are used to denote one element from another. The terms “a”, “an” and “the” herein do not denote a limitation of quantity, and are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The suffix “(s)” as used herein is intended to include both the singular and the plural of the term that it modifies, thereby including one or more of that term (e.g., lance-member(s) 2014j includes one or more lance member).

[0027] Reference throughout the specification to “one exemplary implementation”, “another exemplary implementation”, “an exemplary implementation”, and so forth, means that a particular element (e.g., step, feature, structure, and / or characteristic) described in connection with the exemplary implementation is included in at least one exemplary implementation described herein, and may or may not be present in other exemplary implementations. In addition, it is to be understood that the described elements may be combined in any suitable manner in the various exemplary implementations.

[0028] In the context of the disclosure, the term "operable" means the system and / or the device, or a certain element or step is / are fully functional, sized, adapted and calibrated, comprises elements for, and meets applicable operability requirements to perform a recited function when activated, coupled, implemented, actuated, effected, or realized. In relation to systems, the term "operable" means the system is fully functional and calibrated, having the necessary elements, as well as the mechanisms for, and meets applicable operability requirements to perform a recited function when executed by a user.

[0029] The term “abut” refers in the context of the disclosure, to items that are in direct physical contact with each other, although the items may not be attached, secured, fused, glued, sewn, or welded together.

[0030] In the context of the disclosure, the term “toroid” is, as in geometry, refers to a surface generated by rotating a closed plane curve about a coplanar line that does not intersect the curve. The term toroid refers also to the solid structure enclosed by such a surface.

[0031] The term “elastic” should be understood to mean that, after an axial or radial deflection from a first position into a second position, the elastic component reverts back into the first position. The elastic components (e.g., the elastic stopper, and elastic seal disc) could also be considered to be resilient structures in that they return to their original shape or initial position after a temporary deformation.

[0032] In the context of the disclosure, the term “Shore A hardness refers to the hardness of the elastic components or specific components being referenced. Furthermore, as used herein, the term “hardness” means the property of a composition of material that enables it to resist plastic deformation, usually by penetration. The usual method to achieve a hardness value is to measure the depth or area of an indentation left by an indenter of a specific force applied for a specific time. For example, in ASTM D2240, the specimen is placed on a flat surface and the indenter of the instrument (e.g., a Durometer), is pressed into the material until the durometer's foot rests on the specimen's surface, with a consistent force being applied. The durometer is held in place for 15 seconds, after which a reading is taken from the durometer's scale, measuring the material's hardness in Shore A units (0-100). The specimen is required to be at least 6 mm thick and free from surface imperfections. The process is repeated at least three times, with the durometer being repositioned each time, to account for material variability. The average reading is calculated to represent the material's Shore A hardness, with higher values indicating greater hairiness. The durometer is calibrated regularly to maintain accuracy.

[0033] A more complete understanding of the vial adapter component for a closed and secure fluid transfer providing improved seal between the adapter and the vial, can be obtained by reference to the accompanying drawings. These figures (also referred to herein as “FIG.”) are merely schematic representations based on convenience and the ease of demonstrating the present disclosure, and are, therefore, not intended to indicate relative size, scale and dimensions of the devices or components thereof, and / or to define or limit the scope of the exemplary implementations. Although specific terms are used in the following description for the sake of clarity, these terms are intended to refer only to the particular structure of the exemplary implementations selected for illustration in the drawings, and are not intended to define or limitthe scope of the disclosure. In the drawings and the following description below, it is to be understood that like numeric designations refer to components of like function.

[0034] Turning now to FIG.’s 1A-6, illustrating an exemplary implementation of the vial adapter component for closed and secure fluid transfer providing improved seal between the adapter assembly 10 and vial 20. As illustrated, in an exemplary implementation, provided is vial adapter assembly 10 for closed fluid transfer from vial 20 which comprises: cylindrical body 200 having closed bottom 202 and collar 203 extending from tapering shoulder 204 terminating in open circular lip 201 (see e.g., FIG.s IB, 2, 3B), with elastic stopper 210 (interchangeable with “septum”), engaged within open circular lip 201, and cap 220 partially covering elastic stopper 210 and coupled to lip 201 for example, by threading or crimping. Vial adapter assembly 10 can comprise: basin 102 defining basal portion of vial adaptor 10 having outer annular rim 1021 (see e.g., FIG. IB) and inner annular rim 1020 (see e.g., FIG.s 5, 6). Basin 102 also comprises basally tapering open cylinder 112 (see e.g., FIG.s 1 A, 5, 6), extending basally from inner annular rim 1020 comprising plurality of resilient graspers 1125i configured to engage circular lip 201 of vial 20, open cylinder 112 adapted sized and configured to urge vial adaptor 10 and circular lip 201 to be concentric. Also illustrated is cover 101 defining apical portion of hollow toroid, defining outer lip 1012 (see e.g., FIG.s 1, 6) coupled to outer annular rim 1021 of basin 102, and inner lip 1013, wherein hollow toroid comprised of cover 101, semi-toroid 107, basin 102 and apically tapering cylindrical adapter 106 (see e.g., FIG.s 2, 6) defines hollow toroid 1100, functioning as the expansion chamber for bladder 105 (see e,g., FIG. 5A). Accordingly, apically tapering cylindrical adapter 106 having narrow proximal end 1160 with alignment rail 1164 (see e.g., FIG.s 6, 7A, 7B) operable to engage open distal end of syringe adapter 104 with seal 103, and wide distal end 1162 defining outer ring 1161 coupled to inner rim 1020 of basin 102, wide distal end 1162 defining basal surface 1066, with coaxial lumen 1067 (see e.g., FIG. 5) extending therethrough, wherein proximal end 1160 is in fluid communication with coaxial lumen 1067. Also shown is hollow spike (or needle) 1064 extending distally from basal surface 1066 of wide distal end 1162, hollow spike 1064 comprises first lumen 1068 being in fluid communication with coaxial lumen 1067 of apically tapering cylindrical adapter 106 (see e.g., FIG. 5A); and second lumen 1063 being in fluid communication with expansion chamber 1100 via channel 1061.

[0035] As shown e.g., in FIGs 5A, 6, and 7C, elastic seal 130 disc having upper surface 1030 and lower surface 1031, defining coaxial aperture 1035, having ID130 (See e.g., FIG. 7C) is sized to accommodate spike 1064. Also shown is semi toroid 107 (see e.g., FIG.s IB, 2, 6), comprising circular open channel defining outer diameter 1050 and inner diameter 1052 defining apically open channel 1051 (see e.g., FIG. 6) coupled to cover 101, together forming hollow toroid 1100 forming expansion chamber and is coupled to basin 102, with apically tapering cylindrical adapter 106 extending through tapered cylindrical opening 1055 defined by inner diameter 1052 of semi-toroid 107. Furthermore, Bladder 105 (see e.g., FIG. 5A) is disposed within hollow toroid 1100, configured to receive any fluid from vial 20 in liquid communication with second lumen 1063. Using the vial adapter assembly 10 disclosed herein, and upon engaging vial 20 (e.g., by inserting collar 203 into circular opening 1124, while using radially dispose resilient grasping members 1125i (see e.g., FIG. 6) to engage circular lip 201 (thereby centering vial adapter 10 and vial 20), and using spike 1064, penetrating elastic stopper (in other words, vial septum) 210, disc 130 is adapted, sized, and configured to deform, forming cross section of elastic seal disc 130 (see e.g, FIG. 4B), to have surface that is at least partially complimentary to upper surface 2100 (see e.g., FIG. 3B) of elastic stopper 210 of vial 20. As illustrated, in certain exemplary implementation, that cross section can be concave.

[0036] Accordingly, and as indicated, the devices, systems and methods disclosed form a stand-alone, expanded sealing interface 2102 (see e.g., FIG. 5B), that is independent from the sealing interface 2101 formed between the outer surface 10640 (see e.g., FIG. 7A) of spike 1064, and elastic stopper 210 created by the penetration of spike 1064 of elastic stopper 210 (see e.g., FIG. 2), which may or may not be concentric to coaxial circular aperture 2205 defined in cap 220 (ID2205, see e.g., FIG. 3A). In other words, the deformation of at least the lower surface 1301 of elastic seal disc 130, as illustrated for example, in FIG.s 2, and 5B, forms an expanded sealing interface 2102 between the lower surface 1031 (see e.g., FIG.s 5B 7C) of elastic seal disc 130, and upper surface 2100 of elastic stopper (septum) 210.

[0037] The distinction between a "deformed surface" and a "non-deformed surface", as used herein, refers to the functional behavior and geometric conformation of elastic seal disc 130 during different operational states, such as when engaging and coupling vial adaptor 10 and vial 20 as illustrated, for example in FIG. 1 A.

[0038] As used herein, "non-deformed surface" refers to the initial, unstressed, unstrained and unaltered configuration of elastic seal disc 130 (first position, see e.g., FIG. 5A), particularly lower surface 1031. In this first position, lower surface 1301 of elastic seal disc 130 is not subject to any external forces or constraints that would change its native shape. The edges, contours, and overall topography of elastic seal disc 130 remain as manufactured — commonly smooth, flat, or presented with any original curvature, protrusions or geometry intended by design. Furthermore, in this state, seal disc 130 is not yet in a sealing engagement with upper surface 2100 of vial's 20 elastic stopper 210. There may be a gap or only minimal contact, and the elastic material's molecular structure is not under compression, tension, or shear. In other words, this position is associated with an "at rest" condition, where elastic disc’s 130 surfaces are strain free and retain their initially-defined geometry and topology.

[0039] Conversely, "deformed surface" describes geometric and physical state of elastic seal disc 130, such as, but not limited to lower surface 1031, after elastic seal disc 130 has been transitioned from the first, initial topological configuration, into active engagement as illustrated in FIG. 5B. Upon application of a mechanical force, either by axial movement of vial adapter assembly 10, compression between mating components (e.g., with vial 20), or other designed actuation, lower surface 1301 of elastic seal disc 130 comes into contact with upper surface 2100 of vial’s elastic stopper 210. This results in elastic seal disc 130 undergoing a controlled deformation, meaning that one or both surfaces (lower surface 1301, and upper surface 2100) is forced to adapt or change its shape to complimentary features, irregularities, or flatness of elastic stopper 210, aided at least partially because of the differences in stiffness between elastic seal disc 130 and elastic stopper 210. The initial (non-deformed) surface (see e.g., 1301, FIG. 5A) deforms by compressing, stretching, or flexing, so that a reliable sealing interface 2102 is established (see e.g., FIG. 5B). This “new” sealing interface 2102 is independent of the sealing interface 2101 (see e.g., FIG. 2), formed by the outer surface 10640 (see e.g., FIG. 7B) of spike 1064 and elastic stopper 210, which in turn, is formed by the piercing of elastic stopper 210 by spike 1064. This deformation enables elastic seal disc 130 to essentially "mold" itself against stopper’s surface, potentially filling micro-gaps, or tears formed by the piercing of elastic stopper 210, and providing an effective barrier to fluid, gas, or microbial contamination, forming a complimentary surface curvature to the surface formed by elastic stopper 210, regardless of the angle of penetration of spike 1064. In other words, "deformed" means that the material's surfacetopology / curvature and / or profile have changed from their initial manufactured state as a direct result of the engagement with another surfaces (e.g., that of washer 120, and / or cylinder 113 on one side, against the surface 2100 on the other side), for purpose of functional sealing, thereby forming an independent sealing interface.

[0040] In certain exemplary implementations, the ratio between the outer diameter of seal disc 130 (OD130) and the outer diameter of washer 120 (OD120, see e.g., FIG. 4B), is between 2:1 and 1:2. Furthermore, in another exemplary implementation Shore A value of washer 120, and elastic seal disc 130, is between about 30 and about 70, as measured using ASTM 2240 incorporated herein in its entirety. It is noted that the deformation of at least the lower surface of seal disc 130 will take place regardless of the relative stiffness of the septum. In other words, when the Shore A value of the septum is lower than the Shore A value of the elastic seal disk, the septum will deform more than the lower surface of the seal disc, and still form a surface that is at least partially complementary as disclosed. The deformation of at least the lower surface of the elastic seal disc does not need to be solely by compression against the septum, but can also take place upon compression (or partial compression) against the vial (aluminum) cap.

[0041] Alternatively, when OD120 is equal to, or larger than OD130 (see e.g., FIG. 4B), and wherein outer diameter OD130 of seal disc 130 is greater than the inner diameter of coaxial circular aperture 2205 defined in cap 220 (ID2205, see e.g., FIG. 3A), engaging vial 20 with vial adaptor assembly 10, will cause lower surface 1031 of seal disc 130 to compress against upper surface 2200 of cap, thereby, again, providing a stand-alone sealing interface 2102, that is independent of the sealing interface 2101 between the outer surface 10640 of spike 1064, and elastic stopper 210.

[0042] Additionally, in circumstances where the inner diameter of coaxial circular aperture 2205 defined in cap 220, is larger than outer diameter ODnoof seal disc 130, having the outer diameter OD120 of washer 120, being equal to outer diameter ODnoof elastic seal disc 130, form a lower surface 1301, that would at least partially deform upper surface 2100 of elastic stopper 210, while simultaneously (since seal disc 130 has a Shore A value that is lower than the Shore A value of elastic stopper 220) deforming lower surface 1301 of seal disc 130 making it at least partially complementary to upper surface 2100 of elastic stopper 210, thereby providing a standalone sealing interface 2102, that is an expansion of, and independent of the sealing interface21010 between the outer surface 10640 (see e.g., FIG. 6), of spike 1064, and elastic stopper 210 (see e.g., FIG. 5B).

[0043] It is noted that expansion chamber formed by the hollow toroid 1100 comprised of cover 101, coupled to basin 102 with semi-toroid 107, coupled to cover 101, together forming hollow toroid 1100 and apically tapering cylindrical adapter 106 illustrated in a certain exemplary implementation. Hollow toroid 1100 refers to the solid structure formed of an ovoid, rotating around a coplanar line that does not intersect the curve. However, the skilled artisan would readily recognize that the closed ovoid can be changed to other closed curves, for example that of a toms. Furthermore, bladder 105 disposed within the expansion chamber is configured to receive fluids (gas, liquid) from vial 20 (see e.g., FIG. 5A).

[0044] In another exemplary implementation, the cap 220 (see e.g., FIG. 3A, 3B), for example, an aluminum cap having upper surface 2200 having predetermined outer diameter (OD220), further defines a coaxial circular aperture 2205 (see e.g., FIG. 4B) having a predetermined internal diameter (ID220). Accordingly, elastic seal disc 130 is adapted, sized and configured to an outer diameter OD130, that is larger than cap 220 predetermined internal diameter ID220 and smaller than cap 220 outer diameter OD220, whether in the unstrained position (before penetration of the elastic stopper 210), or in the strained position (inserting collar 203 and engaging grasping members 1125i and circular lip 201, and using spike 1064, penetrating stopper 210).

[0045] Typically, elastic stopper 210 of vial 20 has Shore A hardness of between about 30 and about 60 using ASTM method No. D2240. To obtain and maintain the at least partially complimentary surface upon actuation, within the limits and constraints of off center, and tilted penetration using spike 1064, as dictated by shoulder 204 angles, outer diameter OD220 of cap 220, resilient graspers 1125i and other time constraints, elastic seal disc 130 has Shore A hardness that is lower than, or equal to the Shore A hardness of elastic stopper 210.

[0046] In certain exemplary implementations, deforming the cross section of elastic seal disc 130, in a way that the deformed cross section (e.g., a concave cross section), will be at least partially complimentary to upper surface 2100 of elastic stopper 210 can be done for example as illustrated in FIG 7A, and 7B. Accordingly in an exemplary implementation, basal surface 1066 of apically tapering cylindrical adapter 106 further comprises distally extending cylinder 113 that is coaxial with, and surrounding spike 1064, cylinder 113 is adapted sized and configured tocause lower surface 1031 (see e.g., FIG. 7C) of elastic seal disc 130 to deform, forming for example concave cross section (see e.g., FIG. 4B), that is at least partially complimentary to upper surface 2100 of elastic stopper 210. This is accomplished for example, by maintaining outer diameter ODm (not shown) of cylinder 113 smaller than inner diameter ID220 of aperture 2205 defined by upper surface 2200 of cap 220.

[0047] In yet another exemplary implementation illustrated in FIG.s IB, 2, 4A, and 4B-6 vial adapter assembly 10 further comprises washer 120 having upper surface 1200 and lower surface 1201 defining coaxial aperture 1205. To achieve the complimentary surface, washer 120 is disposed on spike 1064 between elastic seal disc 130 and basal surface 1066 of apically tapering cylindrical adapter 106, with upper surface 1200 of washer 120 abutting basal surface 1066 of apically tapering cylindrical adapter 106, and upper surface 1300 of elastic seal disc 130 abutting lower surface 1201 of washer. Here too, washer 120 is adapted sized and configured to cause lower surface 1031 (see e.g., FIG. 7C) of elastic seal disc 130 to deform, forming for example concave cross section (see e.g., FIG. 4B), that is at least partially complimentary to upper surface 2100 of elastic stopper 210. This can be achieved for example, by maintaining outer diameter ODno of washer 120 as smaller than inner diameter ID220 of aperture 2205 defined by upper surface 2200 of cap 220.

[0048] In certain exemplary implementation, the elastic seal disc, and or the elastic stopper are made from isoprene.

[0049] Furthermore, and in certain exemplary implementations, certain chemotherapy drugs or supportive medications are frequently accessed over an extended period, sometimes spanning several days. This is common in inpatient chemotherapy regimens or outpatient infusion centers where patients receive multi-day treatments. For example, drugs like fluorouracil (5-FU) in continuous infusion protocols or cisplatin in fractionated dosing schedules often require multiple withdrawals from the same vial. A primary concern when using vial adapters for extended periods is the potential for leakage. After initial penetration of the vial's septum, microscopic pathways can form, potentially allowing for drug escape or microbial ingress. This risk increases with each subsequent access, particularly with volatile or high-pressure medications (e.g., cyclophosphamide, fluorouracil, propofol, paclitaxel). Leakage not only poses a contamination risk but can also lead to inaccurate dosing and potential exposure of healthcare workers to hazardous drugs. Accordingly and in another exemplary implementation, provided herein is amethod of increasing seal time between a vial adapter assembly and a vial, implemented in combination with the vial comprising a cylindrical body having a closed bottom and a collar extending from tapering shoulder terminating in an open circular lip, with an elastic stopper engaged within the open circular lip, wherein the vial adapter assembly comprises a seal adapted, sized, and configured to transition from a first position having a cross section that is substantially planar, to a second position having a cross section that is concave with a surface complimentary to the upper surface of the elastic stopper of the vial, the method comprises: coupling the vial adapter to the vial, wherein the vial adapter is configured to perforate the elastic stopper of the vial; and causing the seal to transition from the first position having a cross section that is substantially planar, to the second position having a cross section that is concave with the complimentary surface of the upper surface of the elastic stopper of the vial.

[0050] Accordingly and in an exemplary implementation, provided herein is a vial adapter assembly for a closed fluid transfer from a vial, the vial comprising: a cylindrical body having a closed bottom and a collar extending from tapering shoulder terminating in an open circular lip, with an elastic stopper engaged within the open circular lip, and a cap partially covering the elastic stopper and coupled to the circular lip, wherein the vial adapter assembly comprising an elastic seal disc adapted, sized, and configured to transition from a first position wherein at least a lower surface of the elastic seal disc is not deformed, to a second position wherein the at least lower surface of the elastic seal disc is deformed, forming a sealing interface that is at least partially complimentary to the upper surface of the elastic stopper of the vial, (i) wherein the vial adapter further comprises a hollow spike configured to penetrate the elastic stopper, and wherein the elastic seal disc having an upper surface and a lower surface, defining a coaxial aperture, is coupled to the spike, and (ii) further comprising: a basin defining a basal portion of a hollow toroid having an outer annular rim and an inner annular rim, a basally tapering open cylinder extending basally from the inner annular rim comprising a plurality of radially disposed resilient graspers configured to engage the circular lip of the vial, a cover defining the apical portion of the hollow toroid, defining an outer lip coupled to the outer annular rim of the basin, and an inner lip, wherein the hollow toroid defines an expansion chamber, an apically tapering cylindrical adapter having a narrow proximal end operable to engage an open distal end of a syringe adapter, and a wide distal end coupled to the inner rim of the basin, the wide distal end defining a basal surface, with a coaxial lumen extending therethrough, wherein the proximal end is in fluidcommunication with the coaxial lumen, the hollow spike extending distally from the basal surface of the wide distal end, the hollow spike comprises a first lumen being in fluid communication with the coaxial lumen of cylindrical adapter, and a second lumen being in fluid communication with the expansion chamber, a semi-toroid comprising a circular, apically open channel defining an outer diameter and an inner diameter coupled to the cover, together with the apically tapering cylindrical adapter, forming the hollow toroid coupled to the basin, with the apically tapering cylindrical adapter extending through the inner diameter of the semi toroid, wherein, upon engaging the vial, and penetrating the stopper with the spike, the seal disc is adapted, sized, and configured to transition from the first position wherein at least the lower surface of the elastic seal disc is not deformed, to the second position wherein at least the lower surface of the elastic seal disc is deformed, configured to form the sealing interface that is independent of the sealing interface between the outer surface of the spike and the septum, and at least partially complimentary to the upper surface of the elastic stopper of the vial, wherein (iii) the cap, having a predetermined outer diameter further defines a coaxial circular aperture having a predetermined internal diameter, (iv) the elastic seal disc having an outer diameter that is larger than the cap’s predetermined internal diameter of the coaxial circular aperture, and smaller than the outer diameter of the cap, wherein (v) the elastic stopper of the vial, and the elastic seal disc, each having a Shore A hairiness of between 30 and 70 measured using ASTM D2240, wherein (vi) the basal surface of the apically tapering cylindrical adapter further comprises a distally extending cylinder that is coaxial with the spike, the cylinder is adapted sized and configured to cause the lower surface of the elastic seal disc to transition from the first position wherein at least the lower surface of the elastic seal disc is not deformed, to the second position wherein at least the lower surface of the elastic seal disc is deformed, where (vii) the ratio between the outer diameter of the cylinder and the predetermined internal diameter of the coaxial circular aperture defined by the upper surface of the cap, or the outer diameter of the elastic seal disc, is between 1:2 and 2:1, (viii) the vial adapter assembly further comprising a washer having an upper surface and a lower surface defining a coaxial aperture configured to accommodate the spike, the washer disposed between the elastic seal disc and the basal surface of the apically tapering cylindrical adapter, with the upper surface of the washer abutting the basal surface of the apically tapering cylindrical adapter, and the upper surface of the elastic seal disc abutting the lower surface of the washer, wherein (ix) the ratio between the outer diameter of the washer and the predeterminedinternal diameter of the coaxial circular aperture defined by the upper surface of the cap, or the outer diameter of the elastic seal disc, is between 1:2 and 2:1, wherein (x) the outer diameter of the elastic seal disc is larger than the inner diameter of the coaxial circular aperture defined by the cap, and wherein the outer diameter of the washer is smaller than the outer diameter of the elastic seal disc, or (xi) wherein the outer diameter of the elastic seal disc is smaller than the inner diameter of the coaxial circular’ aperture defined by the cap, and wherein the outer diameter of the washer is equal to the outer diameter of the elastic seal disc, or (xii) wherein the outer diameter of the elastic seal disc is larger than the inner diameter of the coaxial circular aperture defined by the cap, and wherein the outer diameter of the washer is larger than the outer diameter of the elastic seal disc, wherein upon engaging the vial adaptor and the vial, the lower surface of the elastic seal disc is configured to deform and abut at least a portion of the upper surface of the cap, and wherein (xiii) upon engaging the vial adaptor and the vial, the lower surface of the elastic seal disc is configured to form a concave cross section.

[0051] In another exemplary implementation, provided herein is a method of expanding a sealing surface between a vial adapter assembly and a vial, implemented in combination with the vial, the vial comprising a cylindrical body having a closed bottom and a collar extending from tapering shoulder terminating in an open circular lip, with an elastic stopper engaged within the open circular lip, wherein the vial adapter assembly comprises a seal disc adapted, sized, and configured to transition from a first position wherein at least a lower surface of the elastic seal disc is not deformed, to a second position wherein at least the lower surface of the elastic seal disc is deformed, forming a sealing interface that is at least partially complimentary to the upper surface of the elastic stopper of the vial, the method comprises: coupling the vial adapter to the vial, wherein the vial adapter is configured to perforate the elastic stopper of the vial, and causing the seal disc to transition from the first position whereby at least the lower surface of the elastic seal disc that is not deformed, to the second position whereby at least the lower surface of the elastic seal disc is deformed, forming the sealing interface that is at least partially complimentary to the upper surface of the elastic stopper of the vial, and thereby expanding the sealing surface between the vial adapter and the vial, wherein (xiv) the vial adapter further comprises a hollow spike configured to penetrate the elastic stopper, and wherein the elastic seal disc having an upper surface and a lower surface, defining a coaxial aperture, is coupled to the spike, (xv) the vial adapter assembly further comprising: a basin defining a basal portion of ahollow toroid having an outer annular rim and an inner annular rim, a basally tapering open cylinder extending basally from the inner annular rim comprising a plurality of resilient graspers configured to engage the circular lip of the vial, a cover defining the apical portion of the hollow toroid, defining an outer lip coupled to the outer annular- rim of the basin, and an inner lip, wherein the hollow toroid defines an expansion chamber, an apically tapering cylindrical adapter having a narrow proximal end operable to engage an open distal end of a syringe adapter, and a wide distal end coupled to the inner rim of the basin, the wide distal end defining a basal surface, with a coaxial lumen extending therethrough, wherein the proximal end is in fluid communication with the coaxial lumen, a hollow spike extending distally from the basal surface of the wide distal end, the hollow spike comprises a first lumen being in fluid communication with the coaxial lumen of cylindrical adapter, and a second lumen being in fluid communication with the expansion chamber, and a semi-toroid comprising a circular, apically open channel defining an outer diameter and an inner diameter coupled to the cover, together with the apically tapering cylindrical adapter, forming the hollow toroid coupled to the basin, with the apically tapering cylindrical adapter extending through the inner diameter of the semi toroid, wherein, upon engaging the vial, and penetrating the stopper with the spike, the seal disc is adapted, sized, and configured to transition from the first position wherein the at least the lower surface of the elastic seal disc is not deformed, to the second position wherein the at least lower surface of the elastic seal disc is deformed, configured to form the sealing interface that is at least partially complimentary to the upper surface of the elastic stopper of the vial, wherein (xvi) the cap, having a predetermined outer diameter further defines a coaxial circular aperture having a predetermined internal diameter, (xvii) the elastic seal disc has an outer diameter that is larger than the cap’s predetermined internal diameter and smaller than the cap’s outer diameter, wherein (xviii) the elastic stopper of the vial, and the elastic seal disc, each has a Shore A hardness of between 30 and 70 as measured using ASTM D2240, wherein (xix) the basal surface of the apically tapering cylindrical adapter further comprises a distally extending cylinder that is coaxial with the spike, the cylinder is adapted sized and configured to cause at least the lower surface of the elastic seal disc to deform, forming a lower surface that is at least partially complimentary to the upper surface of the elastic stopper, wherein (xx) the ratio between the outer diameter of the cylinder and the predetermined internal diameter of the coaxial circular aperture defined by the upper surface of the cap, or the outer diameter of the elastic seal disc, isbetween 1:2 and 2:1, (xxi) the vial adapter further comprising a washer having an upper surface and a lower surface defining a coaxial aperture configured to accommodate the spike, the washer disposed between the elastic seal disc and the basal surface of the apically tapering cylindrical adapter, with the upper surface of the washer abutting the basal surface of the apically tapering cylindrical adapter, and the lower surface of the washer abutting the upper surface of the elastic seal disc, (xxii) the outer diameter of the washer is smaller than the inner diameter of the aperture defined by the upper surface of the cap, wherein (xxiii) the ratio between the outer diameter of the washer and the predetermined internal diameter of the coaxial circular aperture defined by the upper surface of the cap, or the outer diameter of the elastic seal disc, is between 1:2 and 2:1, wherein (xxiv) the outer diameter of the elastic seal disc is larger than the inner diameter of the coaxial circular aperture defined by the cap, and wherein the outer diameter of the washer is smaller than the outer diameter of the elastic seal disc, or (xxv) wherein the outer diameter of the elastic seal disc is smaller than the inner diameter of the coaxial circular aperture defined by the cap, and wherein the outer diameter of the washer is equal to the outer diameter of the elastic seal disc, wherein the step of causing the seal to transition from the first position to the second position comprises causing the lower surface of the elastic seal disc to deform and abut at least a portion of the upper surface of the cap defining the coaxial circular aperture, or (xxvi) wherein the outer diameter of the elastic seal disc is larger than the inner diameter of the coaxial circular aperture defined by the cap, and wherein the outer diameter of the washer is larger than the outer diameter of the elastic seal disc, wherein the step of causing the seal to transition from the first position to the second position comprises causing the lower surface of the elastic seal disc to deform and abut at least a portion of the upper surface of the cap, and (xxvii) wherein the step of causing the seal to transition from the first position to the second position comprises causing at least the lower surface of the elastic seal disc to form a concave cross section.

[0052] While in the foregoing specification the vial adapter providing an improved seal between the adapter and the vial provided herein have been described in relation to certain exemplary implementations, and many details are set forth for purpose of illustration, it will be apparent to those skilled in the ait that the disclosure of the alignment methods, implementable using the systems disclosed herein are susceptible to additional implementations and that certain of the details described in this specification and as are more fully delineated in the following claims can be varied considerably without departing from the basic principles disclosed herein.

Claims

What is claimed:

1. A vial adapter assembly for a closed fluid transfer from a vial, the vial comprising: a cylindrical body having a closed bottom and a collar extending from tapering shoulder terminating in an open circular lip, with an elastic stopper engaged within the open circular lip, and a cap partially covering the elastic stopper and coupled to the circular lip, wherein the vial adapter assembly comprising an elastic seal disc adapted, sized, and configured to transition from a first position wherein at least a lower surface of the elastic seal disc is not deformed, to a second position wherein the at least lower surface of the elastic seal disc is deformed, forming a sealing interface that is at least partially complimentary to the upper surface of the elastic stopper of the vial.

2. The vial adapter assembly of claim 1, wherein the vial adapter further comprises a hollow spike configured to penetrate the elastic stopper, and wherein the elastic seal disc having an upper surface and a lower surface, defining a coaxial aperture, is coupled to the spike.

3. The vial adapter assembly of claim 2, further comprising: a) a basin defining a basal portion of a hollow toroid having an outer annular rim and an inner annular rim; b) a basally tapering open cylinder extending basally from the inner annular’ rim comprising a plurality of radially disposed resilient graspers configured to engage the circular lip of the vial; c) a cover defining the apical portion of the hollow toroid, defining an outer lip coupled to the outer annular rim of the basin, and an inner lip, wherein the hollow toroid defines an expansion chamber; d) an apically tapering cylindrical adapter having a narrow proximal end operable to engage an open distal end of a syringe adapter, and a wide distal end coupled to the inner rim of the basin, the wide distal end defining a basal surface, with a coaxial lumen extending therethrough, wherein the proximal end is in fluid communication with the coaxial lumen; e) the hollow spike extending distally from the basal surface of the wide distal end, the hollow spike comprises a first lumen being in fluid communication with the coaxial lumen of cylindrical adapter; and a second lumen being in fluid communication with the expansion chamber;f) a semi-toroid comprising a circular, apically open channel defining an outer diameter and an inner diameter coupled to the cover, together with the apically tapering cylindrical adapter, forming the hollow toroid coupled to the basin, with the apically tapering cylindrical adapter extending through the inner diameter of the semi toroid, wherein, upon engaging the vial, and penetrating the stopper with the spike, the seal disc is adapted, sized, and configured to transition from the first position wherein the at least the lower surface of the elastic seal disc is not deformed, to the second position wherein the at least lower surface of the elastic seal disc is deformed, configured to form the sealing interface that is at least partially complimentary to the upper surface of the elastic stopper of the vial.

4. The vial adapter assembly of claim 3, wherein the cap, having a predetermined outer diameter further defines a coaxial circular aperture having a predetermined internal diameter.

5. The vial adapter assembly of claim 2, wherein the elastic seal disc has an outer diameter that is larger than the cap’s predetermined internal diameter of the coaxial circular aperture, and smaller than the outer diameter of the cap.

6. The vial adapter assembly of claim 1, wherein the elastic stopper of the vial and the elastic seal disc, each has a Shore A hardness of between 30 and 70 measured using ASTM D2240.

7. The vial adapter assembly of claim 3, wherein the basal surface of the apically tapering cylindrical adapter further comprises a distally extending cylinder that is coaxial with the spike, the cylinder is adapted sized and configured to cause the lower surface of the elastic seal disc to transition from the first position wherein at least the lower surface of the elastic seal disc is not deformed, to the second position wherein at least the lower surface of the elastic seal disc is deformed.

8. The vial adapter assembly of claim 7, wherein the ratio between the outer diameter of the cylinder and the predetermined internal diameter of the coaxial circular aperture defined by the upper surface of the cap, or the outer diameter of the elastic seal disc, is between 1:2 and 2:1.

9. The vial adapter assembly of claim 3, further comprising a washer having an upper surface and a lower surface defining a coaxial aperture configured to accommodate the spike, the washer disposed between the elastic seal disc and the basal surface of the apically tapering cylindrical adapter, with the upper surface of the washer abutting the basal surface of the apicallytapering cylindrical adapter, and the upper surface of the elastic seal disc abutting the lower surface of the washer.

10. The vial adapter assembly of claim 9, wherein the ratio between the outer diameter of the washer and the outer diameter of the elastic seal disc is between 2:1 and 1:2.

11. The vial adapter assembly of claim 10, wherein the outer diameter of the elastic seal disc is larger than the inner diameter of the coaxial circular aperture defined by the cap, and wherein the outer diameter of the washer is smaller than the outer diameter of the elastic seal disc.

12. The vial adapter assembly of claim 10, wherein the outer diameter of the elastic seal disc is smaller than the inner diameter of the coaxial circular aperture defined by the cap, and wherein the outer diameter of the washer is equal to the outer diameter of the elastic seal disc.

13. The vial adapter assembly of claim 10, wherein the outer diameter of the elastic seal disc is larger than the inner diameter of the coaxial circular aperture defined by the cap, and wherein the outer diameter of the washer is larger than the outer diameter of the elastic seal disc, wherein upon engaging the vial adaptor and the vial, the lower surface of the elastic seal disc is configured to deform and abut at least a portion of the upper surface of the cap.

14. The vial adapter assembly of claim 11 , wherein upon engaging the vial adaptor and the vial, the lower surface of the elastic seal disc is configured to form a concave cross section.

15. A method of expanding a sealing surface between a vial adapter assembly and a vial, implemented in combination with the vial, the vial comprising a cylindrical body having a closed bottom and a collar extending from tapering shoulder terminating in an open circular lip, with an elastic stopper engaged within the open circular lip, wherein the vial adapter assembly comprises a seal disc adapted, sized, and configured to transition from a first position wherein at least a lower surface of the elastic seal disc is not deformed, to a second position wherein at least the lower surface of the elastic seal disc is deformed, forming a sealing interface that is at least partially complimentary to the upper surface of the elastic stopper of the vial, the method comprises: a) coupling the vial adapter to the vial, wherein the vial adapter is configured to perforate the elastic stopper of the vial; and b) causing the seal disc to transition from the first position whereby at least the lower surface of the elastic seal disc that is not deformed, to the second position whereby at least the lower surface of the elastic seal disc is deformed, forming the sealing interface that is at leastpartially complimentary to the upper surface of the elastic stopper of the vial, and thereby expanding the sealing surface between the vial adapter and the vial.

16. The method of claim 15, wherein the vial adapter assembly further comprises a hollow spike configured to penetrate the elastic stopper, and wherein the elastic seal disc having an upper surface and a lower surface, defining a coaxial aperture, is coupled to the spike.

17. The method of claim 15, wherein the vial adapter assembly further comprising: a) a basin defining a basal portion of a hollow toroid having an outer annular rim and an inner annular rim; b) a basally tapering open cylinder extending basally from the inner annular’ rim comprising a plurality of resilient graspers configured to engage the circular lip of the vial; c) a cover defining the apical portion of the hollow toroid, defining an outer lip coupled to the outer annular’ rim of the basin, and an inner lip, wherein the hollow toroid defines an expansion chamber; d) an apically tapering cylindrical adapter having a narrow proximal end operable to engage an open distal end of a syringe adapter, and a wide distal end coupled to the inner rim of the basin, the wide distal end defining a basal surface, with a coaxial lumen extending therethrough, wherein the proximal end is in fluid communication with the coaxial lumen; e) a hollow spike extending distally from the basal surface of the wide distal end, the hollow spike comprises a first lumen being in fluid communication with the coaxial lumen of cylindrical adapter; and a second lumen being in fluid communication with the expansion chamber; and f) a semi-toroid comprising a circular, apically open channel defining an outer diameter and an inner diameter coupled to the cover, together with the apically tapering cylindrical adapter, forming the hollow toroid coupled to the basin, with the apically tapering cylindrical adapter extending through the inner diameter of the semi toroid, wherein, upon engaging the vial, and penetrating the stopper with the spike, the seal disc is adapted, sized, and configured to transition from the first position wherein the at least the lower surface of the elastic seal disc is not deformed, to the second position wherein the at least lower surface of the elastic seal disc is deformed, configured to form the sealing interface that is at least partially complimentary to the upper surface of the elastic stopper of the vial.

18. The method of claim 17, wherein the cap, having a predetermined outer diameter, further defines a coaxial circular aperture having a predetermined internal diameter.

19. The method of claim 16, wherein the elastic seal disc has an outer diameter that is larger than the cap’s predetermined internal diameter and smaller than the cap’s outer diameter.

20. The method of claim 15, wherein the elastic stopper of the vial, and the elastic seal disc, each has a Shore A hardness of between 30 and 70 using ASTM D2240.

21. The method of claim 17, wherein the basal surface of the apically tapering cylindrical adapter further comprises a distally extending cylinder that is coaxial with the spike, the cylinder is adapted sized and configured to cause at least the lower surface of the elastic seal disc to deform, forming a lower surface that is at least partially complimentary to the upper surface of the elastic stopper.

22. The method of claim 21, wherein the ratio between the outer diameter of the cylinder and the predetermined internal diameter of the coaxial circular aperture defined by the upper surface of the cap, or the outer diameter of the elastic seal disc, is between 1:2 and 2:1.

23. The method of claim 17, further comprising a washer having an upper surface and a lower surface defining a coaxial aperture configured to accommodate the spike, the washer disposed between the elastic seal disc and the basal surface of the apically tapering cylindrical adapter, with the upper surface of the washer abutting the basal surface of the apically tapering cylindrical adapter, and the lower surface of the washer abutting the upper surface of the elastic seal disc.

24. The method of claim 23, wherein the outer diameter of the washer is smaller than the inner diameter of the aperture defined by the upper surface of the cap.

25. The method of claim 23, wherein the ratio between the outer diameter of the washer and the predetermined internal diameter of the coaxial circular aperture defined by the upper surface of the cap, or the outer diameter of the elastic seal disc, is between 1:2 and 2:1.

26. The method of claim 23, wherein the outer diameter of the elastic seal disc is larger than the inner diameter of the coaxial circular aperture defined by the cap, and wherein the outer diameter of the washer is smaller than the outer diameter of the elastic seal disc.

27. The method of claim 23, wherein the outer diameter of the elastic seal disc is smaller than the inner diameter of the coaxial circular aperture defined by the cap, and wherein the outer diameter of the washer is equal to the outer diameter of the elastic seal disc, wherein the step ofcausing the seal to transition from the first position to the second position comprises causing the lower surface of the elastic seal disc to deform and abut at least a portion of the upper surface of the cap defining the coaxial circular aperture.

28. The method of claim 23, wherein the outer diameter of the elastic seal disc is larger than the inner diameter of the coaxial circular aperture defined by the cap, and wherein the outer diameter of the washer is larger than the outer diameter of the elastic seal disc, wherein the step of causing the seal to transition from the first position to the second position comprises causing the lower surface of the elastic seal disc to deform and abut at least a portion of the upper surface of the cap.

29. The method of claim 28, wherein the step of causing the seal to transition from the first position to the second position comprises causing at least the lower surface of the elastic seal disc to form a concave cross section.

Images