Patent Publication Number: US-2023149262-A1

Title: Syringe system

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 16/041,170 filed Jul. 20, 2018, which claims the benefit of U.S. Provisional Application Ser. No. 62/685,786, filed on Jun. 15, 2018, the entire contents of which are incorporated herein by reference in their entirety. 
    
    
     BACKGROUND 
     Certain medications have separate components that are mixed prior to administration to a patient. In such situations, a syringe kit can be used wherein the kit includes two syringes that couple to one another. A first syringe contains the first component of the medication and the second syringe contains the second component of the medication. In an example, the first component is in a dry powder form and the second component is in a liquid form. Such two-component syringe systems are necessary when medication components are not compatible with both (i) each other, as well as (ii) syringe component materials, under extended or accelerated storage conditions. 
     In order to mix the two components, the first syringe is mechanically coupled to the second syringe so that the syringes are interlocked with one another. The contents of the two syringes are pushed back and forth, in an alternating manner, between the two syringes such as by actuating plungers associated with the first and second syringes. In this manner, the first and second components are mixed together. After such mixing, the syringes are decoupled from one another and an injection needle can then be attached to whichever syringe contains the resultant mixture. The mixed medication can then be administered to a patient, such as via a subcutaneous injection into the patient. 
     The low cost and pliability of polypropylene make it very common as a material used in the manufacturing of syringes. However, certain solvents (E.g., N-methyl pyrrolidone) leach through polypropylene under long term storage conditions. While cyclic olefin copolymers (COC)/cyclic olefin polymers (COP) do not leach solvents under long term storage conditions, when irradiated, COC/COP can become more brittle. Brittleness can lead to syringe failure during the syringe assembly. COC/COP is also more expensive than polypropylene, making its use not as cost effective. 
     Current drug mixing systems that use such first and second syringes can sometimes achieve improper mixing of the first and second drug components, as described more fully below. In view of this, there is a need for improved systems for mixing components of a medication. 
     SUMMARY 
     A two-component syringe system includes two components configured to couple with each other to mix the contents of each syringe. The coupling occurs in a male-female relationship in an end-to-end fashion. 
     The female syringe is structurally equipped with a lug-type thread configuration that ensures the female syringe and the male syringe can be coupled to one another in a manner that, after assembly, does not impede proper mixing of the contents. In addition, the female syringe has an extended-length female member, or neck, relative to a corresponding length of a prior art female syringe. The extended-length female member ensures that a complementary male member of the male syringe does not extend too far into the female syringe after coupling and impede full and proper advancement of a plunger of the female syringe. This greatly increases the likelihood that the contents of the female and male syringe of the medication are properly mixed by eliminating dead spaces after coupling in the female syringe. 
     In a specific aspect, the male member is tapered with a smaller diameter at the tip relative to the base, while the lumen of the female member matches the taper of the male member. In another specific aspect, the female system further provides for a lug thread in the neck of the female syringe, such that when coupled with a COC/COP male syringe, the tapered male and female coupling interface with cause the lug threads to “slip” after tightening to avoid excess tightening. The slipping releases any excess torque from overtightening, which could otherwise be absorbed by the more brittle COC/COP male syringe, possibly resulting in breakage and syringe failure. In alternative embodiments, the COC/COP syringe can be replaced with a syringe formed from polycarbonate or glass syringe; while the polypropylene syringe can be replaced with one fashioned from polyethylene, such as high-density polyethylene (HDPE) or low density polyethylene (LDPE). Other materials can be used for manufacturing of the components. 
     In another aspect, there is disclosed a female syringe system, comprising: a female syringe formed of: a barrel member defining an internal cavity and having an internal, proximal-most edge that defines a proximal-most edge of the cavity, the barrel member having a proximal opening through which contents can be expelled from the internal cavity; a plunger slidably positioned at least partially within the internal cavity, the plunger having a proximal-most tip, wherein the plunger slides within the internal cavity such that the proximal-most tip slides toward the proximal-most edge of the barrel member in a manner that expels contents of the barrel member through the proximal opening of the barrel member; and a tapered female coupler on a proximal region of the barrel member, the female coupler having an opening that receives a complementary tapered male member of a male syringe to couple the female syringe with the male syringe, wherein the female member has a structural configuration that prevents the male member of the male syringe from protruding into the internal cavity of the barrel member when the male syringe is coupled to the female syringe. 
     In another aspect, there is disclosed a female syringe system, comprising: a female syringe formed of: a barrel member defining an internal cavity and having an internal, proximal-most edge that defines a proximal-most edge of the cavity, the barrel member having a proximal opening through which contents can be expelled from the internal cavity; a plunger slidably positioned at least partially within the internal cavity, the plunger having a proximal-most tip, wherein the plunger slides within the internal cavity such that the proximal-most tip slides toward the proximal-most edge of the barrel member in a manner that expels contents of the barrel member through the proximal opening of the barrel member; and a female coupler on a proximal region of the barrel member, wherein the female coupler couples to a male member of a male syringe, wherein the male syringe includes a concentric sleeve that surrounds the male member, and wherein the male member is longer in length than the sleeve such that a tip of the male member extends past a tip of the sleeve, and wherein the male coupler and female coupler have complementary tapers that limit a depth of insertion of the male member into the female member. 
     Other features and advantages should be apparent from the following description of various implementations, which illustrate, by way of example, the principles of the disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    shows a prior medication component mixing system. 
         FIG.  2    shows a male syringe of the medication component mixing system of  FIG.  1   . 
         FIG.  3 A  shows a prior art female syringe of the medication component mixing system of  FIG.  1   . 
         FIGS.  3 B and  3 C  shows a female coupler portion of the female syringe of  FIG.  3 A . 
         FIG.  4    shows the coupled male syringe and female syringe of the prior medication component mixing system of  FIG.  1   . 
         FIG.  5    shows an improved medication component mixing system. 
         FIG.  6    shows an improved female syringe of the medication component mixing system shown in  FIG.  5   . 
         FIGS.  7  and  8    show enlarged views of a female coupler of the female syringe of  FIG.  6   . 
         FIG.  9    shows the prior art female syringe and improved female syringe. 
         FIG.  10    shows a flange extender. 
         FIGS.  11  and  12    shows the male syringe with the flange extender coupled to a distal flange of the male syringe. 
     
    
    
     DETAILED DESCRIPTION 
     A medication component mixing system formed of a first syringe, such as a female syringe, and a second syringe, such as a male syringe, wherein the system is configured to mix a female portion and a male portion of the medication. The female syringe and the male syringe mechanically couple to one another in an end-to-end fashion for mixing of the contents of the female and male portions. The female syringe includes a female coupler that mechanically couples to a corresponding male coupler of the male syringe. The female coupler includes a lug-type thread configuration that ensures the female syringe and the male syringe can be coupled to one another in a manner that does not impede proper mixing of the components. The female coupler is configured to prevent the male coupler of the male syringe from impeding proper advancement of a plunger of the female syringe during mixing. 
       FIG.  1    shows a side view of a prior art medication component mixing system  105  that includes a first syringe and a second syringe. In a non-limiting example, the first syringe is a female syringe  110  configured to contain at least one component of the medication. The second syringe is a male syringe  115  configured to contain at least a second portion of the medication. The female syringe  110  and the male syringe  115  mechanically couple to one another in an end-to-end fashion for mixing of the separate components of the medication between the female syringe  110  and the male syringe  115 , as described below. As described in more detail below, each of the female syringe  110  and the male syringe  115  includes a corresponding plunger assembly that can be used to expel contents from the respective syringe. The plunger assemblies are described in detail in  FIGS.  2  and  3   . The syringes mechanically couple at a coupling location identified within a circle  140  in  FIG.  1   . The terms “distal” and “proximal” are used herein in relation to the coupling location. 
     The female syringe  110  is formed of an elongated barrel  120  that defines an internal cavity that holds contents (E.g., powder). A plunger rod assembly  125  of the female syringe  110  includes a plunger rod  312  with a plunger rod cap  302  and a proximal plunger  310 . At least a portion of the plunger rod assembly  125  is slidably positioned inside the barrel  120  and can be actuated to push the contents out of the barrel though an opening in the end of the barrel  120 . 
     With reference still to  FIG.  1   , the male syringe  115  is formed of a barrel  130  that defines an internal cavity that holds contents (E.g., liquid). A plunger rod assembly  135  includes a plunger rod  212  with a plunger rod cap  202  and a proximal plunger  210 . At least a portion of the plunger rod assembly  135  is slidably positioned inside the barrel  130  and can be moved within the barrel to push contents (e.g., liquid) out of the barrel  130  though an opening in the end. The barrels  130  and  120  are each formed of elongated bodies. In non-limiting examples, the elongated bodies are cylindrical although the shape may vary. 
     When coupled as shown in  FIG.  1   , the respective openings at the end of the barrels  130  and  120  interlock with one another, providing a junction, so that contents can be transferred between the barrels. In addition, the barrels  130  and  120  are co-axially aligned along a common longitudinal axis when coupled to one another. The plunger rod assemblies  125  and  135  can then be actuated in an alternating manner to move the contents of the barrel  120  and the barrel  130  back and forth into one another via the coupling junction to achieve mixing of the contents. However, the male coupler  205  (shown as hidden lines) of the male syringe  115  extends into the cavity of the barrel  120  at a location  142  in the female syringe  110  as shown in circle  140 . 
       FIG.  2    shows the male syringe  115 . At least a portion of the plunger rod assembly  135  is slidably positioned within the barrel  130 . The plunger rod assembly  135  consists of (i) the plunger rod  212  and (ii) a distal plunger rod cap  202  and (iii) a proximal plunger  210 . The plunger rod cap  202  can be used to actuate the plunger rod  212  within the barrel  130  such as by pushing or pulling on the plunger rod cap  202 . The male syringe  115  also has a distal flange  216 , which can be grasped by a user when operating the plunger rod assembly  135 . The distal flange  216  can be optionally fitted with a flange extender  1005 , which is shown in  FIG.  10   . As shown in  FIG.  10   , the flange extender  1005  is a flange structure that removably attaches to the distal flange  216  ( FIG.  2   ) such as by sliding over the distal flange  216 .  FIGS.  11  and  12    shows the male syringe  115  with the flange extender  1005  coupled to the distal flange  216 . 
     With reference again to  FIG.  2   , the contents of the male syringe  115  are positioned within the cavity of the barrel  130  at a location proximal of the plunger  210  of the plunger assembly  135 . The plunger  210  pushes the contents of the barrel  130  out of an opening at a proximal end of the barrel  130 . The proximal end of the barrel  130  forms a male coupler  205  that inserts into a corresponding female coupler of the female syringe  110  when the male syringe  115  and the female syringe  110  are coupled, as described more fully below. The male coupler  205  has a lumen that communicates with the cavity of the barrel  130  such that the contents of the barrel  130  can exit via the internal lumen of the male coupler  205 . 
     The male coupler  205  is surrounded by a co-axial, annular sleeve  215  that is concentric with the male coupler  205  such that the sleeve  215  surrounds the male coupler  205 . In the illustrated embodiment, the sleeve  215  is cylindrical although the shape may vary. A tip of the male coupler  205  extends proximally past the sleeve  215 . An internal surface of the annular sleeve  215  is threaded such that it can couple with corresponding threads of the female syringe  110 , as described below. 
     In an example embodiment, the male syringe is a TOP PAC syringe (or equivalent thereof) manufactured by Schott Schweiz AG. 
       FIG.  3 A  shows the female syringe  110 , which is a prior art female syringe. The plunger rod assembly  125  consists of a plunger rod  312  and a distal plunger rod cap  302  and a proximal plunger  310 . At least a portion of the plunger rod assembly  125  of the female syringe  110  can slide through the barrel  120  by actuating (such as pushing or pulling) the plunger rod cap  302  at a distal end of the plunger rod  312 . As mentioned, the female syringe  110  has a proximal, female coupler  305  that is sized to receive therein the male coupler  205  ( FIG.  2   ) of the male syringe  115 . The barrel  120  of the female syringe  110  defines an internal cavity that secures the contents at a location proximal of the plunger  310  of the plunger rod assembly  125 . When the female syringe  110  is in a standalone state as shown in  FIG.  3 A , the plunger  310  can be moved to a proximal-most position so that it abuts a proximal-most edge  315  of the internal cavity, as shown in  FIG.  3 A . When positioned as such, the plunger  310  of the plunger assembly  125  can push all the contents out of the barrel  120  via an opening in the female coupler  305 . 
     With reference still to  FIG.  3 A , the female coupler  305  is cylindrical with a lumen that can receive therein the male coupler  205  of the male syringe  115  ( FIG.  2   ) in a male-female relationship. The female coupler  305  is threaded with a thread member  320  that threadedly couples with the corresponding threads of the internal surface of the annular sleeve  215  ( FIG.  2   ). The female coupler  305  is sized and shaped to fit within the complementary-shaped sleeve  215  of the male coupler  205 . In this manner, the female syringe  110  can securely couple to the male syringe  115  as shown in  FIG.  1   . The thread member  320  wraps around or encircles the entire circumference of the female coupler  305 , as shown in  FIGS.  3 B and  3 C , which show enlarged views of the female coupler  305 . 
       FIG.  4    shows the female syringe  110  and the male syringe  115  fully coupled to one another. The plunger rod assembly  135  of the male syringe is not shown in  FIG.  4    although the plunger rod assembly  135  is present in the assembled device as shown in  FIG.  2   . When fully coupled as such, a proximal tip of the male coupler  205  ( FIG.  2   ) extends or pokes into a proximal region of the barrel  120  of the female syringe  110 . In this manner, the proximal tip of the male coupler  205  forms a stop against which the proximal-most edge  405  of the plunger  310  abuts when the plunger assembly  125  is depressed into the barrel  120  of the female syringe  110 . In other words, the protrusion of the male coupler  205  into the barrel  120  prevents the plunger assembly  125  from being fully depressed into the barrel  120  in that it prevents the proximal-most edge  405  of the plunger  310  from contacting the proximal-most edge of the barrel  120 . 
     Thus, as shown in  FIG.  4   , a gap  410  is formed between the proximal-most edge  405  of the plunger  310  and the proximal-most edge  315  of the internal cavity of the barrel  120  of the female syringe  110 . The presence of the gap  410  can result in incomplete mixing of the dry contents of the female syringe  110  with the contents of the male syringe  115  as the plunger assembly  125  may be unable to fully transfer the contents between each syringe. 
     Improved Female Syringe 
     There is now described an example embodiment of an improved female syringe that overcomes the deficiencies of the prior art female syringe  110 . The improved female syringe, referred to as female syringe  510  ( FIG.  6   ), is structurally configured such that, when fully coupled with the male syringe  115 , the male coupler  205  of the male syringe  115  does not and cannot extend into or otherwise penetrate the barrel of the female syringe  510 , as described more fully below. Thus, the plunger assembly of the female syringe  510  can be fully depressed to the proximal-most end of the female syringe barrel to expel all of the contained contents even when the male syringe  115  is fully coupled to the female syringe  110 . 
       FIG.  5    shows the female syringe  510  coupled to the male syringe  115  at a coupling region  140 . As in the prior system, the female syringe  510  and the male syringe  115  can transfer their respective contents into one another when coupled as such for mixing. Note that, when fully coupled, a plunger assembly  625  of the female syringe  510  can be fully depressed such that a proximal-most edge of a plunger  614  can abut a proximal-most edge of a barrel  620  ( FIG.  6   ) of the female syringe  510 . Thus, as shown in circle  140  of  FIG.  5   , there is no gap between the proximal-most edge  405  of the plunger  310  and the proximal-most edge of the barrel of the female syringe  510  as in the prior art system. Moreover, when fully coupled, the male coupler of the male syringe  115  does not extend at all into the barrel of the female syringe  510 . 
       FIG.  6    shows the improved female syringe  510 . As mentioned, the female syringe  510  includes the barrel  620  in which the plunger rod assembly  625  is slidably positioned. The plunger rod assembly  625  includes a plunger rod  612  having a distal rod cap  630  and a proximal plunger  614 . The barrel  620  has an internal cavity defined by a proximal-most edge  640  of the barrel  620 . The female syringe  510  has a distal flange  642 , which can be optionally fitted with a flange extender, such as the flange extender  1005  shown in  FIG.  10   . As mentioned, the plunger rod assembly  625  can be fully depressed such that the proximal plunger  614  abuts the proximal-most edge  640  of the barrel even when the female syringe is fully coupled to the male syringe  115 , as shown in  FIG.  5   . 
     With reference still to  FIG.  6   , the female syringe  510  has a female coupler  645 .  FIGS.  7  and  8    show enlarged views of the female coupler  645  of the female syringe  510 . The female coupler  645  contains an internal lumen that communicates with the cavity of the barrel  620 . The female coupler  645  has at least one external thread member in the form of one or more lugs  705  positioned on opposed sides of the female coupler  645 . The lugs  705  are sized and shaped to threadedly engage the corresponding threads on the internal surface of the annular sleeve  215 . In an embodiment, the lugs are ISO compliant. The lugs  705  have a shape such that the lugs can be fully seated within the threads on the internal surface of the annular sleeve  215 . That is, the lugs  705  can be threaded into the threads on the internal surface of the annular sleeve  215  only to a stop point at which point the male coupler will not and cannot extend into the barrel of the female syringe  510 . 
     As best shown in the view of  FIG.  8   , the female coupler  645  of the female syringe  510  has a non-circular, tabular or at least partial cruciform shape when viewed along the longitudinal axis of the female syringe. In contrast, the female coupler  305  of the prior art female syringe  110  has a circular shape (as shown in  FIG.  3 C ). 
     In addition, the female coupler  645  of the improved syringe  510  has a larger longitudinal length relative to a longitudinal length of the female coupler  305  of the prior art female syringe  110 .  FIG.  9    shows the prior art female syringe  110  and improved female syringe  510  in a side-by-side arrangement. As shown in  FIG.  9   , the female coupler  645  of the improved female syringe  510  has a length L that is longitudinally longer than the length L 1  of female coupler  305  of the prior art female syringe  110 . The female coupler  645  has a length that is selected to accommodate the length of a male coupler of a corresponding male syringe such that the male coupler of the male syringe does not and cannot extend into the barrel of the female syringe when the syringes are coupled to one another. In an example, the female coupler has a length that is longer (by an excess length) than the length of the annular sleeve  215  ( FIG.  2   ) that surrounds the male coupler  205 , wherein the excess length is equal to or greater than a protrusion length by which the male coupler  205  extends longitudinally beyond the annular sleeve  205 . 
     In an embodiment, the female coupler  645  of the female syringe  510  contains a lumen that tapers from a narrow to wider diameter from the barrel toward the proximal tip of the female coupler  645 . The male coupler of the male syringe has a complementary taper with a smaller diameter at the proximal tip relative to the distal base of the male member. This complementary taper physically limits insertion length of the male member into the female member and thereby prevents overtightening. Thus, the male coupler has an outer taper that matches or substantially matches a complementary taper of the inner lumen (i.e., the inner diameter) of the female member such that the complementary taper physically limits insertion length of the male member into the female member. 
     While this specification contains many specifics, these should not be construed as limitations on the scope of an invention that is claimed or of what may be claimed, but rather as descriptions of features specific to particular embodiments. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable sub-combination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a sub-combination or a variation of a sub-combination. Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. 
     Although embodiments of various methods and devices are described herein in detail with reference to certain versions, it should be appreciated that other versions, embodiments, methods of use, and combinations thereof are also possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the embodiments contained herein.