The present invention generally relates to treatment of a dual chamber syringe, and more specifically to treatment of a pre-fillable dual chamber syringe and methods of use thereof for reconstitution and injection of a medicament.
Pre-fillable dual chamber syringes are known in the art for separately containing several different substances, such as a powder/liquid medicament preparation and a solvent in different chambers of the syringe.
It is also known that pre-fillable dual chamber syringes preferably include a syringe barrel with several pistons, which are slidably sealingly disposed therewithin and divide the syringe barrel into several separate chambers, whereas one of the chambers contains a powder medicament and another contains a solvent. Alternatively, both chambers may include liquids that are stored separately and that shall be mixed only at the time of injection.
The pre-fillable dual chamber syringes also include a plunger rod, which is operative to engage one of the pistons. Upon displacement of the plunger rod relative to the syringe barrel, the pistons are advanced within the syringe barrel and permit reconstitution of the medicament by mixing the powder medicament with the solvent using a bypass formed in the syringe barrel.
It is known that a substantial friction force is created between the pistons and the pre-fillable dual chamber syringe, which the user needs to overcome during displacement of the plunger rod relative to the pre-fillable dual chamber syringe.
It is additionally known that one of the methods to reduce this friction force is treatment of the inner surface of the pre-fillable dual syringe with a lubricant, however oftentimes when one of the substances contained in the pre-fillable dual syringe contacts the lubricant, the lubricant is mixed into the substance and may cause either degradation of the substance due to contact with the lubricant or may cause a phenomenon of agglomeration, i.e., increase in the mean particle size of the substance. Agglomeration is known to reduce the dissolution rate between the two substances and thus has a negative effect on the efficacy of the medicament.
The present invention seeks to provide an improved medical container. There is thus provided in accordance with an embodiment of the present invention or a combination of embodiments thereof a medical container, comprising a barrel having an inner surface partially treated with a friction reducing agent; the barrel having at least one substance chamber and wherein the at least one substance chamber defines a portion of the inner surface, which is not treated with the friction reducing agent.
Preferably, the at least one substance chamber defines two substance chambers and at least one of the two substance chambers defines the portion of the inner surface, which is not treated with the friction reducing agent. Further preferably, wherein a drug preparation is configured to be contained within the at least one substance chamber confined by a piston, and the inner surface defined by the at least one substance chamber is not treated with friction reducing agent to avoid contact between the drug preparation and the friction reducing agent, and wherein the remainder of the inner surface of the barrel is treated with friction reducing agent.
Still further preferably, wherein a drug preparation is configured to be contained within the at least one substance chamber confined by a piston, and the inner surface defined by the at least one substance chamber is not treated with friction reducing agent to avoid contact between the drug preparation and the friction reducing agent, and wherein the remainder of the inner surface of the barrel is treated with friction reducing agent.
Yet further preferably, the friction reducing agent is a lubricant. Alternatively, the friction reducing agent is a coating substance.
Preferably, partial treatment of the inner surface of the barrel with friction reducing agent provides both for reduced friction forces between the barrel and the piston and for avoiding damage of the drug preparation during storage, due to lack of contact between the treated area of the barrel and the drug preparation.
In accordance with an embodiment of the present invention, a dual chamber syringe, comprising a barrel having a forward end and a rearward end, the barrel has an inner surface; a forward stopper, a first piston and a second piston rearwardly spaced from the first piston; the first piston and the second piston are configured to be slidably displaceable relative to the barrel; a first chamber is defined between the forward stopper and the first piston; a second chamber is defined between the first piston and the second piston and wherein the inner surface is partially treated with a friction reducing agent, such that in storage the inner surface defined by at least one of the first chamber and the second chamber is not treated with the friction reducing agent.
Preferably, the friction reducing agent is selected from a group of: a lubricant or a coating substance. Further preferably, at least one bypass protrusion arranged along the longitudinal extent of the syringe barrel. Still further preferably, a plunger rod is configured to be partially inserted into the barrel and slidably displace at least one of the first and second pistons relative to the barrel. Yet further preferably, a drug preparation is confined within the first chamber and a solvent is confined within the second chamber and upon longitudinal displacement of the first and second pistons relative to the barrel, the drug preparation and the solvent are configured for reconstitution and subsequent ejection from the barrel.
In accordance with an embodiment of the present invention, the inner surface that contains the bypass protrusion and adjacent to the bypass protrusion is not treated with friction reducing agent. Preferably, the inner surface of the barrel is only treated with friction reducing agent in the region where the first piston is configured to be seated in storage and axially rearwardly therefrom and in the region where the forward stopper is configured to be seated in storage and axially forwardly therefrom.
Further preferably, the inner surface of the barrel defined between the forward stopper and the first piston is not treated with friction reducing agent, thereby preventing contact between a drug preparation and between the friction reducing agent in storage. Still further preferably, a forward portion of the forward stopper and a rearward portion of the first piston are configured to contact the areas of the inner surface that is treated with friction reducing agent in storage.
Still further preferably, substantially the entire circumference of the second piston contacts one of the areas of the inner surface that are treated with friction reducing agent. Yet further preferably, partial treatment of the inner surface of the barrel with friction reducing agent is configured to reduce friction forces that are created during displacement of the plunger rod and the pistons relative to the barrel.
In accordance with an embodiment of the present invention, partial treatment of the inner surface of the barrel with friction reducing agent provides both for reduced friction forces and avoiding damage of the drug preparation during storage, due to lack of contact between the treated area and the drug preparation.
Preferably, the forward stopper is configured to be slidably displaceable relative to the barrel. Further preferably, the forward stopper is configured to be releasable from the barrel.
The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which:
The principles, uses and implementations of the teachings herein may be better understood with reference to the accompanying description and figures. Upon perusal of the description and figures present herein, one skilled in the art is able to implement the invention without undue effort or experimentation.
Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its applications to the details of construction and the arrangement of the components and/or methods set forth in the following description and/or illustrated in the drawings and/or the Examples. The invention can be implemented with other embodiments and can be practiced or carried out in various ways. It is also understood that the phraseology and terminology employed herein is for descriptive purpose and should not be regarded as limiting.
Some embodiments of the invention are described herein with reference to the accompanying figures. The description, together with the figures, makes apparent to a person having ordinary skill in the art how some embodiments of the invention may be practiced. The figures are for the purpose of illustrative discussion and no attempt is made to show structural details of an embodiment in more detail than is necessary for a fundamental understanding of the invention. For the sake of clarity, some objects depicted in the figures are not to scale.
Reference is now made to
As seen in
It is also seen in
It is noted that alternatively only two pistons may be contained within the syringe barrel 104, whereas in storage the first substance is sealed in this case by a forward stopper that is releasable from the syringe barrel 104 after reconstitution. Specifically, in accordance with this embodiment, the first substance, such as a drug preparation is preferably confined between the forward stopper 122 and the first piston 124 and a second substance, such as a solvent is preferably confined between the first piston 124 and the second piston 126. In accordance with this alternative embodiment, the luer lock element 110 is preferably obviated and a luer is integrally made with the syringe barrel 104, whereas the forward stopper is releasably connected to the luer in storage in order to seal the first substance and is configured to be released from the luer of the syringe during use.
It is noted that the first and the second substances may be in a form of solid medicament preparation, powder or liquid.
The syringe barrel 104 is preferably made of glass. The syringe barrel has a generally cylindrical shape and extends along the longitudinal axis 103. A bypass protrusion 128 is disposed generally at an intermediate location of the syringe barrel 104 along axis 103. The bypass protrusion 128 generally extends radially outwardly from an outer surface of the syringe barrel 104 to facilitate fluid passage between the two chambers formed within the syringe barrel 104 between each pair of pistons.
It is appreciated that syringe assembly 102 can be any type of conventional container, such as a cartridge commercially available from Schott Pharmaceutical Systems, Mainz, Germany or Vetter Pharma International USA Inc., IL, USA or Nuova Ompi S.r.l., Padua, Italy or may be any other suitable syringe or cartridge.
A plunger rod assembly 130 preferably includes a plunger rod inner portion 132 and a plunger rod outer portion 134, which are preferably fixedly coupled with each other upon insertion of the plunger rod inner portion 132 into the plunger rod outer portion 134. Alternatively, the plunger rod assembly 130 may be an integrally formed element or split in any other way suitable for manufacturing.
The plunger rod assembly 130 is operatively associated with the finger grip 120 and is displaceable with respect thereto and thus, with respect to the syringe barrel 104. In certain operative orientations, the plunger rod assembly 130 is rotatable about longitudinal axis 103 with respect to the finger grip 120 and the syringe barrel 104. In other operative orientations, the plunger rod assembly 130 is axially displaceable along longitudinal axis 103 relative to said finger grip 120 and the syringe barrel 104.
Reference is now made to
The plunger rod inner portion 132 preferably is an integrally formed element, preferably injection molded of plastic and is arranged along longitudinal axis of symmetry 103.
The plunger rod inner portion 132 preferably includes a longitudinal shaft 150 terminating at a generally circular flange 152 at a rearward end 154 thereof. The circular flange 152 extends generally radially outwardly from the outer surface of the longitudinal shaft 150 and is disposed generally transversely with respect thereto. A generally widened longitudinal portion 156 extends forwardly from a forward end 158 of the longitudinal shaft 150 and an externally threaded protrusion 160 extends forwardly from a forward end 162 of the widened longitudinal portion 156.
Typically, two diametrically opposed snap protrusions 164 are formed on two opposite sides of the widened longitudinal portion 156. Snap protrusions 164 generally extend radially outwardly from the widened longitudinal portion 156 and are adapted for fixedly connecting the plunger rod inner portion 132 with the plunger rod outer portion 134. Each of the snap protrusions 164 preferably includes a rearwardly facing surface 166, which is disposed generally transversely with respect to the longitudinal axis 103.
Reference is now made to
The plunger rod outer portion 134 preferably is an integrally formed generally cylindrical hollow element, preferably injection molded of plastic and is arranged along longitudinal axis of symmetry 103.
The plunger rod outer portion 134 has a longitudinal shaft 178, which preferably includes a longitudinal rearward portion 180, terminating at a generally circular flange 182 at a rearward end 184 thereof. The circular flange 182 extends generally radially outwardly from the outer surface of the rearward portion 180 and is disposed generally transversely with respect thereto. The rearward portion 180 has a forward end 186, from which an intermediate externally threaded portion 190 extends forwardly up to a forward portion 192, terminating at a forwardmost circumferential edge 194. It is noted that the outer diameter of the rearward portion 180 is somewhat greater than the outer diameter of the forward portion 192.
The plunger rod outer portion 134 has an outer surface 195 and an inner surface 196, formed by a longitudinal through bore 198.
A guiding track 200 is formed on the outer surface 195 of the plunger rod outer portion 134. The guiding track 200 includes a longitudinal track portion 202 and a helical track portion 204 connected thereto.
It is seen in
It is appreciated that alternatively, the engaging snap protrusion 164 might be located on the plunger rod outer portion 134 while engaging with a forwardly facing shoulder located on the plunger rod inner portion 132, thus preventing the plunger rod inner portion 132 from rearward axial displacement relative to the plunger rod outer portion 134.
It is appreciated that alternatively the plunger rod assembly 130 may be formed as a single integrally made element, without fixedly connecting plunger rod inner and outer portions.
Reference is now made to
It is seen in
The luer lock element 110 is fixedly attached to the forward end 106 of the syringe barrel 104. It is noted that alternatively, the syringe barrel 104 and the luer lock element 110 may be formed as an integral part. Further alternatively, a needle can be fixedly attached to the luer lock element 110 or to a luer that is formed as part of the syringe barrel, in case the syringe barrel and the luer lock element are integrally formed.
The inner cap element 112 is releasably mounted over the luer lock element 110 and is releasably held therein. The outer cap element 114 surrounds the inner cap element 112 and is disposed in friction-fit engagement therewith.
Alternatively, in an embodiment that comprises only two pistons, the luer lock element 110 is obviated and a luer is integrally made with the syringe barrel 104, whereas the forward stopper 122 is releasably connected to the luer in this storage operative orientation and configured to seal the first substance within the syringe barrel 104.
It is additionally seen in
It is noted that drug preparation 440 is confined between the forward piston 122 and the intermediate piston 124 and the forward piston 122 is used for sealing the drug preparation 440 between the two pistons 122 and 124.
It is particularly seen in
It is noted that solvent 450 is confined between the rearward piston 126 and the intermediate piston 124.
The plunger rod inner portion 132 is inserted into the plunger rod outer portion 134 and is fixedly held therein, thereby forming the plunger rod assembly 130. It is noted that the flange 152 of the plunger rod inner portion 132 is supported against rearwardly facing surface 242 of the plunger rod outer portion 134 to prevent forward displacement of the plunger rod inner portion 132 relative to the plunger rod outer portion 134. It is further noted that the snap protrusions 164 of the plunger rod inner portion 132 are supported against forwardly facing shoulder 246 of the plunger rod outer portion 134 to prevent rearward displacement of the plunger rod inner portion 132 relative to the plunger rod outer portion 134.
The plunger rod inner portion 132 is preferably prevented from rotation relative to the plunger rod outer portion 134 due to the fact that the plunger rod inner portion 132 is received into a generally hexagonal bore 198 of the plunger rod outer portion 134, As particularly seen in
The plunger rod assembly 130 is operatively associated with the finger grip 120 and is displaceable with respect thereto and thus, with respect to the syringe barrel 104. As described in detail in U.S. patent application Ser. No. 16/994,596, the finger grip 120 comprises at least one tooth 300 protruding radially inwardly from an inner surface thereof and configured to engage the guiding track 200 of the plunger rod outer portion 134.
In this storage operative orientation, the plunger rod assembly 130 is partially axially inserted into the syringe barrel 104, such that the teeth 300 of the finger grip 120 are not yet engaged with the guiding track 200 of the plunger rod outer portion 134.
It is particularly seen in
It is a particular feature of an embodiment of the present invention that only a portion of the inner surface 109 of the syringe barrel 104 is treated with friction reducing agent 460.
It is a further particular feature of an embodiment of the present invention that only a portion of the inner surface 109 of the syringe barrel 104 is treated with friction reducing agent 460, preferably the annular portion of the inner surface 109 that contains the bypass protrusion 128 and the area adjacent the bypass protrusion 128 is not treated with friction reducing agent 460. Specifically, the inner surface 109 of the syringe barrel 104 is only treated with friction reducing agent 460 in the region where the intermediate piston 124 is configured to be seated in storage and axially rearwardly therefrom and in the region where the forward piston 122 is configured to be seated in storage and axially forwardly therefrom. The inner surface 109 of the syringe barrel 104 defined between the forward piston 122 and the intermediate piston 124 is not treated with friction reducing agent 460, thus preventing contact between one substance, such as drug preparation 440, and between the friction reducing agent 460 in this storage operative orientation.
It is particularly seen in
It is noted that treatment of the inner surface 109 of the syringe barrel 104 with friction reducing agent 460 reduces friction forces that are created during displacement of the plunger rod assembly 130 and the pistons 122, 124 and 126 relative to the syringe barrel 104.
It is a particular feature of an embodiment of the present invention that partial treatment of the inner surface 109 with friction reducing agent 460 provides both for reduced friction forces and avoiding damage or agglomeration of the substance, such as drug preparation 440, during storage, due to undesirable contact of the substance with friction reducing agent 460 for prolonged periods of time.
It is a particular feature of an embodiment of the present invention that two chambers are formed within the dual chamber syringe 100, whereas one substance, such as drug preparation 440, is contained within the first chamber defined between the forward piston 122 and the intermediate piston 124 and the second substance, such as solvent 450, is contained within the second chamber defined between the intermediate piston 124 and the rearward piston 126, whereas the inner surface 109 of the syringe barrel 104 defining the first chamber is not treated with friction reducing agent 460 and the remainder of the inner surface 109 is treated with friction reducing agent 460.
It is noted that various materials can be used as friction reducing agents 460 and for pistons 122, 124 and 126. For example, a grade of friction reducing agent can be used, which may be cured to create a solid-state friction reducing agent layer, which prevents leakage of the friction reducing agent 460 into the first chamber and thus prevents its contact with the drug preparation 440. Furthermore, partial coating or partial lubrication of the inner surface 109 of the syringe barrel 104 may be used in order to reduce friction forces between the pistons 122, 124 and 126 during displacement of the plunger rod 130 relative to the syringe barrel 104.
The friction reducing agent 460 may be a lubricant, such as silicone, for example.
It is noted that alternatively a standard plunger rod can be utilized in accordance with an embodiment of the present invention instead of the plunger rod assembly 130.
In an alternative embodiment mentioned hereinabove, only two pistons may be disposed within the syringe barrel 104, such as first piston 124 and second piston 126. The two pistons 124 and 126 are configured to be slidably displaceable relative to the syringe barrel 104 and a forward stopper 122 may be releasably connected to the forward end of the syringe barrel 104 or to the luer thereof. In accordance with this embodiment of the present invention the portion of the inner surface 109 that is not treated with the friction reducing agent 460 is disposed between the first piston 124 and the forward stopper 122 and the remainder inner surface 109 of the barrel 104 is treated with the friction reducing agent 460. The first substance is contained within the first chamber, which is defined between the forward stopper 122 and the first piston 124, whereas the first substance is typically a drug preparation. The second substance is contained within the second chamber, which is defined between the first piston 124 and the second piston 126, whereas the second substance is typically a solvent. The inner surface defined by the first substance chamber is preferably not treated with friction reducing agent 460 to avoid contact between the medication and the friction reducing agent 460, but the remainder of the inner surface of the barrel 104 is treated with friction reducing agent 460. This partial treatment of the inner surface of the barrel allows for avoiding negative effects resulting from contact between the medication and the friction reducing agent 460 in storage and providing reduced friction forces while displacing the pistons relative to the barrel 104.
It is further noted that a single chamber medical container may be utilized in accordance with an embodiment of the present invention, such as a standard pre-filled syringe or cartridge, which contains medication concealed therewithin by a piston. It is a particular feature of an embodiment of the present invention that the medication is concealed within a substance chamber defining an inner surface. The inner surface defined by this substance chamber is preferably not treated with friction reducing agent 460 to avoid contact between the medication and the friction reducing agent 460, but the remainder of the inner surface of the syringe or cartridge is treated with friction reducing agent 460. This partial treatment of the inner surface of the syringe or cartridge allows for avoiding negative effects resulting from contact between the medication and the friction reducing agent 460 in storage and providing reduced friction forces while displacing a plunger rod rearwardly relative to the syringe or cartridge, such as during aspiration of fluid into the substance chamber.
Reference is now made to
It is seen in
It is appreciated that all spatial relationships between the various components of the dual chamber syringe 100 remain the same as described hereinabove with respect to the storage operative orientation illustrated in
It is particularly seen in
It is also seen in
It is noted that friction forces between the pistons 122, 124 and 126 and the inner surface 109 of the syringe barrel 104 are reduced during displacement of the plunger rod assembly 130 relative to the syringe barrel 104 due to the partial treatment of the inner surface 109 with friction reducing agent 460. In this exemplary embodiment, the lack of contact between the first substance contained in the first chamber of the dual chamber syringe 100 and the friction reducing agent 460 is maintained. Particularly, as seen in
It is particularly seen in
Reference is now made to
It is seen in
The dual chamber syringe 100 is shown during the medicament reconstitution in
It is noted that the longitudinal dimension of the externally threaded portion 190 is preferably defined as the length that is required to axially displace the intermediate piston 124 toward the bypass protrusion 128 of the syringe barrel 104 and to axially displace the rearward piston 126 up to engagement with the intermediate piston 124.
It is appreciated that all spatial relationships between the various components of the dual chamber syringe 100 remain the same as described hereinabove with respect to the pre-reconstitution operative orientation illustrated in
In this medicament reconstitution operative orientation, the plunger rod assembly 130 is rotated about the longitudinal axis and due to thread-like engagement of the teeth 300 of finger grip 120 with the helical track portion 204 of the guiding track 200 of the plunger rod assembly 130, the plunger rod assembly 130 is forwardly displaced longitudinally along longitudinal axis 103.
It is noted that in this medicament reconstitution operative orientation shown in
It is seen in
The rotational displacement of the plunger rod assembly 130 is translated to axial forward displacement thereof along longitudinal axis 103 due to thread-like engagement between the plunger rod assembly 130 and the finger grip element 120, specifically between the helical track portion 204 of the plunger rod assembly 130 and the teeth 300 of the finger grip element 120.
It is noted that upon initiation of axial forward displacement of the plunger rod assembly 130, all three pistons, namely the forward piston 122, the intermediate piston 124 and the rearward piston 126 are displaced together and remain at a constant distance one from another up until the point where the intermediate piston 124 is axially aligned with the bypass protrusion 128 of the syringe barrel 104. At this point, when the intermediate piston 124 is aligned with the bypass protrusion 128, fluid flow passage is established between the two chambers of the dual chamber syringe 100 and solvent 450 is transferred into the chamber containing the drug preparation 440 through the bypass protrusion 128.
Once the intermediate piston 124 is aligned with the bypass protrusion 128, the plunger rod assembly 130 along with the rearward piston 126 are forwardly displaced axially due to the thread-like engagement that is explained in detail hereinabove, toward the intermediate piston 124 until all solvent 450 is transferred into the chamber containing drug preparation 440.
It is noted that in the medicament reconstitution operative orientation, shown in
It is particularly seen in
Reference is now made to
It is seen in
The dual chamber syringe 100 is shown at the end of medicament reconstitution in
It is appreciated that all spatial relationships between the various components of the dual chamber syringe 100 remain the same as described hereinabove with respect to the reconstitution operative orientation illustrated in
In this end of medicament reconstitution operative orientation, the plunger rod assembly 130 completed its thread-like rotation relative to the finger grip element 120 and now the teeth 300 of the finger grip element 120 engage the longitudinal track portion 202 of the guiding track 200 of the plunger rod assembly 130.
It is particularly seen that upon further thread-like rotation of the plunger rod assembly 130 relative to the finger grip element 120 the teeth 300 of the finger grip element 120 reach the rearward end of the helical track portion 204, then continuously pass through the longitudinal track portion 202 of the guiding track 200.
In this end of medicament reconstitution operative orientation, further rotation of the plunger rod assembly 130 relative to the finger grip element 120 is prevented, due to engagement of the teeth 300 of the finger grip element 120 with the longitudinal track portion 202 of the guiding track 200.
It is noted that the plunger rod assembly 130 is prevented from rotational displacement relative to the finger grip element 120 and relative to the syringe assembly 102 during the entire injection process due to engagement of the guided teeth 300 of the finger grip element 120 with the longitudinal track portions 202 of the plunger rod assembly 130 along the entire longitudinal extent of the longitudinal track portions 202.
It is seen that at this end of medicament reconstitution operative orientation shown in
It is seen in
It is appreciated that the dual-chamber syringe 100 is now ready for injection of the liquid medicament solution 470 upon removal of the outer cap element 114, subsequent removal of the inner cap element 112 and connection of a needle to the luer lock element 110.
It is appreciated that upon axial forward displacement of the plunger rod assembly 130 relative to the syringe barrel 104, all pistons 122, 124 and 126 are displaced together up until the point where the forward piston 122 reaches the intermediate portion of the luer lock element 110 and then the rearward piston 126 along with the intermediate piston 124 are displaced forwardly relative to the forward piston 122 until all liquid medicament solution 470 is transferred into the male luer through grooves formed in the luer lock element 110.
It is noted that in this end of medicament reconstitution operative orientation, as shown in
The first substance, such as medicament preparation 440 is now fully reconstituted with the solvent 450 and the liquid medicament solution 470 is now sealingly contained between the forward piston 122 and the intermediate piston 124. It is noted that the liquid medicament solution 470 may contact the friction reducing agent 460, but since this operative orientation is momentary, this contact does not cause damage to the drug preparation 440.
It is particularly seen in
Reference is now made to
It is seen in
The dual chamber syringe 100 is shown at the end of injection in
It is appreciated that all spatial relationships between the various components of the dual chamber syringe 100 remain the same as described hereinabove with respect to the end of reconstitution operative orientation illustrated in
It is seen in
It is seen in
It is a particular feature of an embodiment of the present invention that the friction forces between the pistons 122, 124 and 126 and the inner surface 109 of the syringe barrel 104 are reduced during displacement of the plunger rod assembly 130 relative to the syringe barrel 104 due to the partial treatment of the inner surface 109 with friction reducing agent 460. It is appreciated that during ejection of the liquid medicament solution 470 out of the syringe barrel 104, the outer surface of at least one of the pistons 122, 124 and 126 contacts the inner surface 109 of the syringe barrel 104 that is treated with friction reducing agent 460, thus minimizing the high friction forces that the user would otherwise have to overcome during displacement of the plunger rod 130 with all of the three pistons 122, 124 and 126 relative to the syringe barrel 104. Preferably, the outer surface of all three of the pistons 122, 124, 126 contacts the inner surface 109 of the syringe barrel 104 that is treated with friction reducing agent 460.
It will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather the scope of the present invention includes both combinations and sub-combinations of various features described hereinabove as well as variations and modifications thereof which are not in the prior art.
Reference is hereby made to U.S. patent application Ser. No. 16/994,596, filed Aug. 18, 2020 and entitled “Dual Chamber Syringe and Methods of Use Thereof”, the disclosure of which is hereby incorporated by reference in its entirety. Reference is hereby additionally made to U.S. Provisional Patent Application Ser. No. 63/408,126, filed Sep. 20, 2022 and entitled “TREATMENT OF DUAL CHAMBER SYRINGE AND METHODS OF USE THEREOF”, the disclosure of which is hereby incorporated by reference in its entirety and priority of which is hereby claimed pursuant to 37 CFR 1.78(a) (4) and (5)(i).
Number | Date | Country | |
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63408126 | Sep 2022 | US |