The present disclosure relates to a syringe assembly including a syringe configured to store a drug solution, a seal member that seals the drug solution in a syringe in a fluid-tight manner, a syringe assembly including the seal member, and a prefilled syringe.
In recent years, a prefilled syringe in which a drug solution is prefilled is widely used. This type of prefilled syringe obviates the need to aspirate the drug solution from a vial bottle into the syringe at the time of drug solution administration, making it possible to reduce the time needed for administration.
For example, JP 11-502731 A discloses a technique to prevent a drug solution from leaking out of a syringe before administration of the drug solution. JP 11-502731 A describes a technique of providing a slit to a stopper for sealing the drug solution.
With the technique described in JP 11-502731 A, however, there is a possibility that the drug solution stored in the syringe may leak from the slit during storage or transportation. Furthermore, in the case of a prefilled syringe in which a drug solution and a medical agent are mixed, there is a possibility that the drug solution leaks out from the medicine chamber containing the drug solution and the drug solution and the medical agent are mixed against an intention of the user.
In consideration of the above-described problems, one object of certain embodiments described herein is to provide a seal member, a syringe assembly, and a prefilled syringe capable of inhibiting drug solution from leaking out of a syringe before administration of a drug solution.
According to one embodiment, a seal member is used for a syringe assembly comprising a syringe including a cylinder body that is configured to be filled with a drug solution, and is configured to be disposed in the cylinder body. The seal member comprises a tubular main body part, a closed end part, and a cleavable part. The main body part includes an aperture part that is formed in a proximal end thereof and a tight contact part configured to be form a fluid-tight seal with an inner wall of the cylinder body. The closed end part is formed integrally and continuously with the main body part at the distal end of the main body part, and seals off the distal end of the main body part. The cleavable part is formed in the closed end part, and is connected with the aperture part. In addition, the main body part is disposed in the cylinder body together with a gasket that is slidable in the cylinder body, and is positioned distal of the gasket in the cylinder body, thereby forming a drug solution storage space for storing the drug solution together with the gasket and the cylinder body. The cleavable part is cleaved by a prescribed pressure being applied in a drug solution storage space, and forms a liquid transmission aperture that connects with the aperture part at the closed end part.
According to another embodiment, a syringe assembly includes the above-described seal member, and the syringe. The seal member is disposed in the cylinder body.
According to another embodiment, a prefilled syringe comprises the above-described syringe assembly, the gasket, and the drug solution. The gasket is slidably disposed in a cylinder hole of the cylinder body within the syringe. The syringe is filled with a drug solution. The drug solution is stored in a drug solution storage space formed by the seal member, the gasket, and the cylinder body.
According to certain embodiments of the seal member, the syringe assembly and the prefilled syringe, it is possible to seal the drug solution in the syringe.
Hereinafter, exemplary embodiments of a seal member, a syringe assembly, and a prefilled syringe will be described with reference to
1-1. Configuration Example of Prefilled Syringe
First, an exemplary configuration of a prefilled syringe according to a first exemplary embodiment of the present invention will be described with reference to
The prefilled syringe 1 of this example is prefilled with a drug solution M1 to be administered to a living body. As illustrated in
[Syringe]
The syringe 2 includes a cylinder body 6 in which the drug solution M1 is filled, and a fixed part 7 that is continuous with the cylinder body 6. The cylinder body 6 has a substantially cylindrical shape. The fixed part 7 is continuously formed on the distal end side of the cylinder body 6. The proximal end side of the cylinder body 6 is open. The drug solution M1 is filled in the cylinder hole 6a of the cylinder body 6, and a gasket 12 of the pusher 4 described below is inserted from a proximal end side of the cylinder body 6.
A proximal end part 3b of the needle tube 3 fixed to the fixed part 7 protrudes from an inner distal end surface 6b of the distal end part of the cylinder hole 6a of the cylinder body 6, allowing connection between the needle tube 3 and the cylinder hole 6a. The seal member 20 is disposed on the inner distal end surface 6b of the cylinder hole 6a.
While the cylinder body 6 of the syringe 2 has a substantially cylindrical shape in this example, the shape of the cylinder body 6 may be a hollow quadrangular prism shape or a hexagonal prism shape.
The fixed part 7, which is one example of a holding portion, protrudes from the distal end side of the cylinder body 6 in its axial direction. The fixed part 7 has a columnar shape. In the fixed part 7, an outer diameter of an intermediate part in the axial direction of is smaller than an outer diameter of both end parts in the axial direction. This gives the fixed part 7 a shape in which the intermediate part is necked down. The needle tube 3 is fixed to the fixed part 7 by a fixing method such as insert molding, adhesion with an adhesive or the like.
Examples of the constituent material of the syringe 2 having the above-described configuration includes various types of resins such as polyvinyl chloride, polyethylene, polypropylene, cyclic polyolefin, polystyrene, poly-(4-methylpentene-1), polycarbonate, acrylic resin, acrylonitrile-butadiene-styrene copolymers, polyesters such as polyethylene terephthalate, butadiene-styrene copolymers, and polyamides (for example, nylon 6, nylon 6.6, nylon 6.10, and nylon 12). Among them, it is preferable to use a resin such as polypropylene, cyclic polyolefin, polyester, and poly-(4-methylpentene-1). It is preferable that the material of the syringe 2 is substantially transparent in order to ensure the visibility of the interior.
The medical agent to be filled in the syringe 2 may be any medical agent normally used as an injection, and examples of these include protein medical agents such as antibodies, peptide medical agents such as hormones, nucleic acid medical agents, cell medical agents, blood products, vaccines to prevent various types of infectious diseases, anticancer agents, anesthetics, narcotics, antibiotics, steroids, protease inhibitors, carbohydrate, heparin, carbohydrate injection solutions such as glucose, electrolyte correction injection solutions such as sodium chloride and potassium lactate, vitamins, fat emulsions, contrast agents, and stimulants.
[Needle Tube]
It is prescribed to use the needle tube 3 having a size of 10 to 33 gauge (outer diameter: φ 3.5 mm to 0.2 mm) according to the ISO standard for a medical needle tube (ISO 9626: 1991/Amd 1: 2001(E)), and preferably a size of 16 to 33 gauge (outer diameter: φ1.7 mm to 0.2 mm). The distal end of the needle tube 3 has a blade surface formed to make the needle point 3a to have an acute angle. The living body is punctured with the needle point 3a at the distal end of the needle tube 3.
An example of the material of the needle tube 3 is stainless steel. It is not limited thereto, however, and it is possible to use aluminum, an aluminum alloy, titanium, a titanium alloy, and other metals. As the needle tube 3, not only a straight needle but also a tapered needle having a tapered shape at least in part can be used. As the tapered needle, the proximal end part has a larger diameter than the end part of the needle point 3a, and the intermediate part thereof may have a tapered structure. Furthermore, a sectional shape of the needle tube 3 may be not only a circular shape but also a polygonal shape such as a triangle.
Furthermore, a coating agent formed of a silicone resin, a fluorine-based resin, or the like, is applied to a surface of the needle tube 3 on the needle point 3a side. This makes it possible to reduce friction between the skin and the needle tube when the living body is punctured with the needle tube 3 and to reduce the pain accompanying the puncture.
The needle tube 3 is fixed to the syringe 2 with the needle point 3a protruding outward. Then, the needle point 3a at the distal end of the needle tube 3 protrudes from the distal end of the fixed part 7 of the syringe 2. Moreover, the proximal end part 3b being the proximal end side of the needle tube 3 is exposed from the inner distal end surface 6b of the cylinder body 6 of the syringe 2 toward the cylinder hole 6a. This allows connection between the needle tube 3 and the cylinder hole 6a of the cylinder body 6 of the syringe 2.
[Pusher]
Next, the pusher 4 will be described.
The pusher 4 includes a push rod 11 and a gasket 12. The push rod 11 is formed in a rod shape and is pressed by a user. The distal end part of the push rod 11 is inserted into the cylinder hole 6a of the cylinder body 6. The length of the push rod 11 in the axial direction is set to be substantially equal to or longer than a length that enables sliding movement of the gasket 12 along the inside of the cylinder hole 6a of the cylinder body 6.
A coupling part 11a is formed at the distal end part of the push rod 11. The coupling part 11a is, for example, a male screw portion formed at the distal end part of the push rod 11. The coupling part 11a is inserted into a coupled part 12a of the gasket 12 and screwed with a coupled part 12a.
The gasket 12 is slidably disposed in the cylinder hole 6a of the cylinder body 6. The gasket 12 is formed in a substantially columnar shape and is in close contact with a wall surface of the cylinder hole 6a of the cylinder body 6 in a fluid-tight manner. The gasket 12 partitions the inside of the cylinder hole 6a of the cylinder body 6 into two. The space on more toward the inner distal end surface 6b side than the gasket 12 in the cylinder hole 6a is to be a fluid chamber in which the drug solution M1 is filled.
The gasket 12 has a closed distal end and the open proximal end. The coupled part 12a is formed at the proximal end of the gasket 12. Furthermore, the distal end part 12b of the gasket 12 is formed in a substantially frustoconical shape corresponding to the shape of the inner distal end surface 6b of the cylinder body 6.
The coupled part 12a is, for example, a female screw portion. The coupled part 12a is screwed with the coupling part 11a of the push rod 11, so as to couple the push rod 11 with the gasket 12. When the push rod 11 is pressed by the user, the gasket 12 slides and moves in the cylinder hole 6a of the cylinder body 6, so as to push the drug solution M1 filled in the cylinder hole 6a toward the proximal end part 3b of the needle tube 3.
While the material of the gasket 12 is not particularly limited, it is preferable to be formed of an elastic material in order to improve fluid tightness with the cylinder body 6. Examples of the elastic material include various rubber materials such as natural rubber, isobutylene rubber and silicone rubber, various thermoplastic elastomers such as olefin type and styrene type, and mixtures of these.
[Cap]
The cap 5 is formed in a substantially cylindrical shape, with the proximal end open, and the distal end closed. The cap 5 is formed of an elastic member such as rubber or elastomer. As illustrated in
Note that the inner diameter of the proximal end part of the cylinder hole 5a of the cap 5 is set to be substantially equal to or slightly smaller than the outer diameter of the intermediate part of the fixed part 7. Therefore, when the cap 5 is attached to the syringe 2, an outer circumferential surface of the intermediate part of the fixed part 7 is brought into close contact with an inner circumferential surface of the cap 5. This allows the needle point 3a side of the needle tube 3, which is the distal end side from the intermediate part of the fixed part 7, to be hermetically sealed by the intermediate part and the inner circumferential surface of the cap 5. As a result, it is possible to prevent bacteria from attaching to a portion of the needle tube 3 including the needle point 3a protruding to the distal end side from the fixed part 7. It is sufficient that the inner circumferential surface of the cap 5 is in close contact with the outer circumferential surface of the fixed part 7 so as to hermetically close a space around the portion protruding from the fixed part 7 of the needle tube 3 to the distal end side.
The inner circumferential surface of the cap 5 tightens, by its elastic force, the necked portion being the intermediate part of the fixed part 7. As a result, the inner circumferential surface of the cap 5 and the necked portion of the fixed part 7 are engaged with each other, making it possible to prevent detachment of the cap 5 from the syringe 2 during conveyance.
Furthermore, the needle point 3a of the needle tube 3 has not punctured the cap 5. This suppresses occurrence of coring in the needle tube 3 and damage in the needle point 3a of the needle tube 3.
[Seal Member]
Next, the seal member 20 will be described with reference to
As illustrated in
As illustrated in
The distal end side rib part 21a and the proximal end side rib part 21b are in close contact with a wall surface of the cylinder hole 6a of the cylinder body 6 in a fluid-tight manner. Therefore, the distal end side rib part 21a and the proximal end side rib part 21b form a fluid-tight seal with the inner wall of the cylinder body 6. This configuration achieves fluid-tight sealing of the drug solution M1 filled in the drug solution storage space formed between the seal member 20 and the gasket 12, making it possible to preventing leakage of the drug solution M1 from the seal member 20 and the needle tube 3 in a state before administration of the drug solution. Furthermore, with the two ribs, namely, the distal end side rib part 21a and the proximal end side rib part 21b provided in the main body part 21, it is possible to reliably prevent leakage of the drug solution M1 from the seal member 20.
The distal end side rib part 21a and the proximal end side rib part 21b are in slidable contact with the wall surface of the cylinder hole 6a of the cylinder body 6. This facilitates operation of inserting the seal member 20 into the cylinder hole 6a of the cylinder body 6 in assembling the prefilled syringe 1. In addition, it is possible to prevent tilting of the seal member 20 within the cylinder body 6 by the distal end side rib part 21a and the proximal end side rib part 21b.
Furthermore, a separation part 21c is formed between the distal end side rib part 21a and the proximal end side rib part 21b. The separation part 21c is a recess recessed in a ring shape from the outer circumferential surface of the main body part 21. When the seal member 20 is inserted into the cylinder hole 6a of the cylinder body 6, the separation part 21c separates from the wall surface of the cylinder hole 6a. Therefore, a space is formed by the separation part 21c between the distal end side rib part 21a and the proximal end side rib part 21b. With facilitates deformation of the seal member 20 by the pressure from the drug solution M1 while maintaining the sealability.
As illustrated in
The pressurizing part 24 has two pressurizing surfaces 24a. As illustrated in
The cleavable part 25 is linearly formed in a direction orthogonal to the center in the axial direction of the main body part 21 and the closed end part 22, that is, in a direction orthogonal to the axial direction of the cylinder body 6. The cleavable part 25 connects with the aperture part 23 formed in the main body part 21. In addition, the closed end part 22 is formed to be thinner in the vicinity of the cleavable part 25 than in the other sites.
The cleavable part 25 has a linear part 25b extending from the pressurizing part 24 in the axial direction of the seal member 20, and two pressure-receiving surfaces 25a. The pressure-receiving surface 25a is formed continuously with the distal end of the linear part 25b. The two pressure-receiving surfaces 25a are formed in a tapered shape to have an interval between the two pressure-receiving surfaces 25a and 25a narrows as separated from the linear part 25b and toward the distal end of the closed end part 22. This leads to formation of the cleavable part 25 as a tapered recess having a flow path continuously reduced toward the distal end of the closed end part 22.
Then, when a prescribed pressure is applied to the drug solution storage space at administration of the drug solution M1 to the living body, the two pressure-receiving surfaces 25a of the cleavable part 25 deform in a direction away from each other, and this causes cleavage in a thin wall portion in the vicinity of the cleavable part 25 in the closed end part 22, leading to formation of a liquid transmission aperture T1 in the closed end part 22 (refer to
While the material of the seal member 20 is not particularly limited, it is preferable that the seal member 20 be formed of an elastic material in order to improve fluid tightness with the cylinder body 6. Examples of the elastic material include various rubber materials such as natural rubber, isobutylene rubber and silicone rubber, various thermoplastic elastomers such as olefin type and styrene type, and mixtures of these.
In addition, the syringe 2 and the seal member 20 before filling the drug solution M1 constitute a syringe assembly.
1-2. Drug Solution Administration Operation
Next, operation of administering the drug solution M1 in the prefilled syringe 1 having the configuration described above will be described with reference to
Note that the cap 5 or another member is not punctured with the needle point 3a of the needle tube 3 in a state before administration of the drug solution, as illustrated in
First, when the pusher 4 is pressed by the user to slidably move the gasket 12 within the cylinder hole 6a, the seal member 20 receives pressure from the drug solution M1 pushed out by the gasket 12 as illustrated in
The pressure from the drug solution M1 is received by the two pressurizing surfaces 24a of the pressurizing part 24 and the two opposed surfaces such as the two pressure-receiving surfaces 25a of the cleavable part 25, making it possible to integrate pressures from the drug solution M1. Furthermore, with the presence of the linear part 25b provided between the two pressurizing surfaces 24a and the two pressure-receiving surfaces 25a, it is possible to further integrate the pressures from the drug solution M1 toward the two pressure-receiving surfaces 25a of the cleavable part 25 from the pressurizing part 24.
In addition, a ring-shaped separation part 21c is formed on the outer circumferential surface of the main body part 21 in the vicinity of the pressurizing part 24. This separation part 21c facilitates elastic deformation of the seal member 20 by the pressure from the drug solution M1, and facilitates separation of the two pressurizing surfaces 24a of the pressurizing part 24 away from each other.
Furthermore, when the drug solution M1 is pushed out toward the inner distal end surface 6b of the cylinder hole 6a by the gasket 12, a force is applied to the two pressure-receiving surfaces 25a to separate from each other further by the pressure from the drug solution M1 as illustrated in
When the drug solution M1 is further pushed out toward the inner distal end surface 6b of the cylinder hole 6a by the gasket 12, as illustrated in
The drug solution M1 is further pushed out toward the inner distal end surface 6b of the cylinder hole 6a by the gasket 12, cleaving the distal end of the cleavable part 25 as illustrated in
Then, as illustrated in
In addition, the distal end side rib part 21a is provided in the vicinity of the closed end part 22 of the main body part 21, with the distal end side rib part 21a adjacent to the inner distal end surface 6b of the cylinder body 6. This prevents entrance of the drug solution M1 into a portion between the distal end side rib part 21a and the proximal end side rib part 21b from a gap between the inner distal end surface 6b and the closed end part 22 of the seal member 20 when the drug solution M1 is discharged.
In addition, the closed end part 22 of the seal member 20 is formed in a substantially frustoconical shape complementarily to the shape of the inner distal end surface 6b of the cylinder body 6 in the syringe 2. This makes it possible to reduce the amount of the drug solution M1 remaining between the inner distal end surface 6b and the closed end part 22 of the seal member 20 when the drug solution M1 is discharged.
Furthermore, in the seal member 20 of this example, the cleavable part 25 to be cleaved is formed linearly with one cleaving direction. This configuration makes it possible to integrate the stress applied to the cleavable part 25 by the pressure from the drug solution M1, enabling reduction of the resistance generated when the cleavable part 25 is cleaved. This leads to facilitation of cleaving of the cleavable part 25 at the closed end part 22 of the seal member 20 when the drug solution M1 is administered, enabling facilitation of administration operation of the drug solution M1.
Next, a prefilled syringe according to a second exemplary embodiment will be described with reference to
In a prefilled syringe 41 according to the second exemplary embodiment illustrated in
The prefilled syringe 41 illustrated in
A space formed by the seal member 20 and the gasket 12 of the pusher 4 in the cylinder hole 6a is filled with the drug solution M1. A medical agent storage space is formed by the inner wall and the inner distal end surface 6b of the cylinder body 6 and the seal member 20. The medical agent storage space stores the powdered medical agent N1. In a state of mixing the drug solution M1 and the medical agent N1, the drug solution M1 is sealed in a fluid-tight manner in the cylinder hole 6a by the seal member 20 and the gasket 12. This makes it possible to prevent the drug solution M1 from leaking out before mixing the drug solution M1 with the medical agent N1, and to prevent mixing of the drug solution M1 and the medical agent N1 against an intention of the user.
A cap 51 is attached to the fixed part 7 of the syringe 2. The cap 51 is formed in a substantially cylindrical shape, with the proximal end side open, and the distal end side closed. A sealing portion 51b is provided on the distal end side in the cylinder hole 51a of the cap 51. Then, the needle point 3a of the needle tube 3 and the fixed part 7 are inserted into the cylinder hole 51a of the cap 51, the sealing portion 51b is punctured with the needle point 3a of the needle tube 3. This makes it possible to inhibit leakage of the medical agent N1 from the needle tube 3.
Next, administration operation of the prefilled syringe 41 according to the second exemplary embodiment will be described with reference to
First, as illustrated in
Next, as illustrated in
Next, as illustrated in
Because other configurations are similar to the configuration of the prefilled syringe 1 according to the first exemplary embodiment, description will be omitted. The above-configured prefilled syringe 41 can also obtain similar operational effects as the prefilled syringe 1 according to the first exemplary embodiment described above.
Exemplary embodiments of the present invention have been described above, along with their operational effects. However, the seal member and the prefilled syringe according to the present invention are not limited to the above-described embodiments, and various modifications are possible while remaining within the scope of the invention described in the claims.
While the above-described exemplary embodiment is an example in which a single seal member 20 is provided, the present invention is not limited to this example. For example, a plurality of seal members may be disposed in the cylinder hole of the cylinder body in the syringe, with a plurality of types of drug solutions of different types stored in the syringe.
In addition, while, in the above examples, the needle tube is fixed to a syringe, the present invention is not limited thereto. The needle tube and the syringe may be configured to be detachable from each other and the needle tube may be attached to the syringe when the drug solution is administered.
Number | Date | Country | Kind |
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2016-067698 | Mar 2016 | JP | national |
The present application is a bypass continuation of PCT Appl. No. PCT/JP2017/012794, filed on Mar. 29, 2017, which claims priority to Japanese Appl. No. 2016-067698, filed on Mar. 30, 2016. The contents of these applications are hereby incorporated by reference in their entireties.
Number | Date | Country | |
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Parent | PCT/JP2017/012794 | Mar 2017 | US |
Child | 16141848 | US |