Medical injector with filtering needle cap

Abstract

A tapered profile needle cap for an open tip of a medical syringe facilitates extraction of filtered medication through a septum of a medication vial into the syringe. A needle filter within the cavity of the needle cap has a distal end facing the open cap tip and a proximal end in abutting, fluid-tight contact with the needle tip. The needle filter captures particulate matter in the medicament drawn into the syringe cavity through the hollow needle while preventing fluid passing therethrough from flowing outside the hollow needle.

Description

Technical Field

[0001] The present disclosure generally relates to a medical syringe with a needle cap having a filter. More particularly, embodiments of the syringe with a needle cap of the present disclosure facilitate withdrawing a drug from a vial through a septum of the vial; the drug is filtered through a needle filter within the needle cap and then aspirated into the injection needle of the syringe while the needle cap is coupled to the needle interface of the syringe. Background Art

[0002] Liquid medications and other pharmaceutical agents are typically stored in glass ampoules or glass vials and sealed with an elastomeric stopper, which includes but is not limited to a stopper with a slotted septum. Generally, a two-stage drug administration process is employed to withdraw the drug contained within the vial into the syringe using a filling needle, which is subsequently replaced with a hypodermic needle prior to administering the drug to a patient. In such a typical two-stage process, a blunt-tipped filling needle with a cylindrical outer profile is attached to the Luer connector of the syringe to pierce the stopper / septum, and then the syringe plunger is retracted to withdraw the drug into the syringe chamber. After filling the syringe with the desired amount of drug, the blunt-tipped filling needle is then removed from the syringe and replaced with a hypodermic needle for injecting the drug into the patient.

[0003] In the case of a glass ampoule-type drug vial, to access the pharmaceutical agent, the ampoule is opened by breaking the glass neck. Breaking the glass neck may introduce glass fragments and debris into the pharmaceutical agent, thereby contaminating the drug payload. Prior to administering the drug to a patient, the fragments must be removed from the contaminated pharmaceutical agent. Typically, the glass fragments or other debris are removed by aspirating the contaminated pharmaceutical agent through a filtering device fixed to the end of the syringe. The filtering device generally includes a filling needle, cannula, or straw containing a filter element.

[0004] In the two-stage filtering and drug administration process, the needle or straw has a filter element fixed in the needle and connector interface portion. As the liquid payload is aspirated into the syringe, the filter intercepts the debris, thereby removing it from the liquid payload to be administered. The filtered straw or needle is then removed from the syringe and discarded. Then a replacement hypodermic needle is attached to the syringe for administering the drug contained within the syringe to the patient. To avoid inadvertently administering the contaminated liquid payload to the patient, the filtered needle must be carefully removed and discarded and replaced with an injection administration needle / interface.

[0005] Attaching and replacing two different types of filling needles and injection needles to a syringe is both cumbersome and time-consuming. Each individual attachment introduces potential drug administration errors and / or contamination. When a blunt filling needle (whether filtered or non-filtered) is detached from the syringe, any residual drug that has been drawn into the internal cavity of the filling needle but has not entered the syringe cavity is wasted. Generally, a blunt filling needle with a cylindrical profile cannot completely draw out all the drug contained in a vial because the flat needle tip cannot maintain contact with the residual drug located in the bottom corner of the vial.

[0006] There are blunt, cylindrical-profile needle caps with filter elements that attach to the hypodermic needle of an attached syringe. During syringe aspiration, the drug is drawn into the distal end of the filter cap beyond the opening. The filtered drug flows through the attached injection needle into the syringe barrel. The blunt, filtered needle cap wastes any residual drug drawn into the "dead space" of the cap and any drug remaining in the corners of the vial that cannot be aspirated through the blunt tip of the cap. Summary of the Invention

[0007] A medical syringe with a tapered-profile needle cap having an open end facilitates drawing filtered drug through the septum of a drug vial into the syringe. A needle filter within the cavity of the needle cap has a distal end facing the open cap end and a proximal end in fluid-tight contact abutting the needle tip of the attached hypodermic needle. The needle filter captures particulate matter in the drug drawn through the hollow injection needle into the syringe cavity while preventing fluid passing through it from flowing outside the hollow needle. The tapered profile of the needle cap helps to more completely evacuate the drug in the corners of the drug vial. The sealed contact of the filter with the end of the hollow needle prevents drug from flowing into the dead space of the needle cap between the filter and the needle interface. Thus, the tapered, filtered needle cap of the present disclosure wastes less drug by more effectively evacuating the vial and reducing the dead space within the needle cap to be discarded. When the needle cap is coupled to the needle interface of the syringe, drug is drawn directly through the injection needle of the syringe through the needle filter within the needle cap from the vial. After the drug aspiration process into the syringe is complete, the needle cap is removed, thereby exposing the previously attached injection needle of the syringe, and the syringe is ready at any time to administer the filtered drug to a patient. By having the injection needle already attached to the syringe prior to drug aspiration, the likelihood of potential syringe contamination that may occur during a two-stage drug administration process is reduced, in which a used, filtered filling needle is first removed from the syringe interface and replaced with a hypodermic needle.

[0008] One aspect of the present disclosure relates to a medical syringe that includes a syringe barrel having a proximal end, a distal end, and a syringe cavity therein. The syringe has a plunger and an associated plunger stopper in the proximal end of the syringe barrel. A male Luer connector is on the distal end of the syringe barrel and is in fluid communication with the syringe cavity. A Luer needle adapter is coupled to the male Luer connector and is in fluid communication with the syringe cavity. A hollow syringe needle has a proximal end coupled to the Luer needle adapter and in fluid communication with the syringe cavity, and a distal open needle tip. The syringe is coupled to a needle cap that has a tubular body having an inner wall surface that defines a cap interior cavity therein. The needle cap captures the distal open needle tip. The inner wall surface of the needle cap further defines a first cavity portion that is end-open and has a female Luer-tapered profile on the proximal end of the tubular body, the first cavity portion being coupled to the needle adapter, and the inner wall surface of the needle cap defines an open cap end on the distal end of the tubular body. A fluid-permeable needle filter is positioned within the cap interior cavity. The needle filter has a distal end facing the open cap end and a proximal end in fluid-tight contact in abutment with the open needle tip. The needle filter divides the cap interior cavity into a second proximal portion and a third distal portion that are separated from each other. The needle filter captures particulate matter in the fluid drawn into the syringe cavity through the hollow needle while preventing fluid passing therethrough from flowing from the third distal portion of the hollow cavity to the second proximal portion of the hollow cavity outside of the hollow needle. The tubular body has a tapered, frustoconical outer surface profile on its distal end that terminates in the open cap end. In some embodiments, the proximal end of the needle filter defines a partial-depth through-hole that is not in communication with the distal end of the filter; the needle tip is captured within the filter through-hole and is in sealing engagement with the filter through-hole. In other embodiments, the needle tip pierces and penetrates the proximal end of the needle filter but does not penetrate the distal end of the needle filter. In other embodiments, the needle tip abuts and compresses the proximal end of the needle filter.

[0009] Another aspect of the present disclosure relates to a syringe comprising a syringe barrel having a proximal end and a distal end and a syringe cavity therein. A plunger and an associated plunger stopper are positioned in the proximal end of the syringe barrel. A male Luer connector in fluid communication with the syringe cavity is present on the distal end of the syringe barrel. A Luer needle adapter is coupled to the male Luer connector of the syringe barrel and is in fluid communication with the syringe cavity. A hollow syringe needle has a proximal end in fluid communication with the syringe cavity and coupled to the Luer needle adapter, and a distal open needle tip. The syringe includes a needle cap having a tubular body with an inner wall surface that defines a cap interior cavity therein, the cap interior cavity capturing the distal open needle tip. The inner wall surface of the needle cap further defines a first cavity portion at the proximal end of the tubular body that is end-open and has a female Luer-tapered profile, the first cavity portion being coupled to the needle adapter. The inner wall surface of the needle cap defines an open cap end at the distal end of the tubular body, a retaining shoulder axially spaced from the open cap end, and a radially inwardly directed lip axially spaced from the retaining shoulder. A fluid-permeable needle filter of a porous polymer structure is positioned within the cap interior cavity, the needle filter being interposed between the retaining shoulder and the radially inwardly directed axial lip. The needle filter has a distal end facing the open cap end and a proximal end defining a partial-depth through-hole that does not communicate with the distal end of the filter. The needle tip is captured within the filter through-hole and is sealingly engaged with the filter through-hole. The needle filter divides the cap interior cavity into a second proximal portion and a third distal portion that are separated from each other. The needle filter captures particulate matter in the fluid withdrawn through the hollow needle into the syringe cavity while preventing fluid passing therethrough from flowing from the third distal portion of the hollow cavity to the second proximal portion of the hollow cavity outside the hollow needle. The tubular body of the needle cap has a tapered, frustoconical outer surface profile at its distal end that terminates in the open cap end.

[0010] Another aspect of the present disclosure relates to a syringe that includes a syringe barrel having a proximal end, a distal end, and a syringe cavity therein. A plunger and an associated plunger stopper are positioned within the proximal end of the syringe barrel. A male Luer connector is positioned on the distal end of the syringe barrel and is in fluid communication with the syringe cavity. A Luer needle adapter is coupled to the male Luer connector and is in fluid communication with the syringe cavity. The syringe includes a hollow syringe needle having a proximal end that is coupled to the Luer needle adapter and is in fluid communication with the syringe cavity, and a distal open needle tip. The syringe further includes a needle cap having a tubular body with an inner wall surface that defines a cap interior cavity therein, the cap interior cavity capturing the distal open needle tip. The inner wall surface of the needle cap further defines a first cavity portion that is end-open and has a female Luer-tapered profile on the proximal end of the tubular body, the first cavity portion being coupled to the needle adapter. The inner wall surface of the needle cap further defines an open cap tip on the distal end of the tubular body, a retaining shoulder that is axially spaced from the open cap tip, and a radially inwardly directed lip that is axially spaced from the retaining shoulder. A fluid-permeable needle filter of a porous polymer structure is positioned within the cap interior cavity, the needle filter being interposed between the retaining shoulder and the radially inwardly directed axial lip. The needle filter has a distal end facing the open cap tip and a proximal end. In this embodiment, the needle tip pierces through and seals in engagement with the proximal end of the needle filter. The needle filter divides the cap interior cavity into a second proximal portion and a third distal portion that are separated from each other. The needle filter captures particulate matter in the fluid drawn into the syringe cavity through the hollow needle while preventing fluid passing therethrough from flowing from the third distal portion of the hollow cavity to the second proximal portion of the hollow cavity outside the hollow needle. In this embodiment, the tubular body has a tapered, frustoconical outer surface profile on its distal end that terminates in the open cap tip. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In the following detailed description, exemplary embodiments of the present disclosure are further described in conjunction with the accompanying drawings, wherein:

[0012] Figure 1 is an isometric view of a medical syringe of the present disclosure with an attached needle cap and needle guard;

[0013] Figure 2 is Figure 1 an axial cross-sectional view of the medical syringe of

[0014] Figure 3 isFigure 2 Axial sectional view of the connected needle cap, subcutaneous injection needle of the syringe, and needle interface;

[0015] Figure 4 is Figure 1 Exploded view of a medical syringe, needle cap, and needle guard;

[0016] Figure 5 is Figure 1 View of the needle cap and syringe, where the syringe withdraws medication through the septum of a vial;

[0017] Figure 6 is an alternative embodiment of the needle cap, subcutaneous injection needle of the syringe, and needle interface; and

[0018] Figure 7 is another alternative embodiment of the needle cap, subcutaneous injection needle of the syringe, and needle interface.

[0019] For ease of understanding, wherever possible, the same reference numerals are used to denote the same elements in the various figures. The figures are not drawn to scale. Detailed Description

[0020] A medical syringe with a filter needle cap helps withdraw filtered medication from a vial through the septum of the vial into the syringe. When the needle cap is connected to the needle interface of the syringe, medication that may contain contaminating debris (such as glass fragments) is withdrawn directly from the vial through the needle filter within the needle cap, and the needle cap makes a sealed abutting contact with the end of the injection needle of the syringe. The proximal end of the needle cap is connected to the needle interface of the syringe, where the end of the syringe needle makes a sealed contact and engagement with the proximal end of the needle filter. In use, the open end, i.e., the tapered distal end, of the needle cap is inserted through the septum of the medication vial. By retracting the syringe plunger, under negative pressure, the medication is withdrawn directly through the needle filter and the hollow syringe needle into the syringe chamber through the open end of the needle cap. The needle filter separates contaminants in the medication payload and prevents them from entering the hollow needle and the syringe cavity. The sealed contact between the proximal end of the needle filter and the end of the injection needle inhibits the accumulation of excess medication in the dead space between the proximal end of the needle filter and the needle interface. Thus, the filtered medication that is not withdrawn into the syringe chamber is not wasted. The tapered distal end of the needle cap helps to completely withdraw the medication from the vial, especially around the corners of the vial. After the process of withdrawing the medication into the syringe is complete, the needle cap is removed, and the syringe is ready to be used to administer the medication to a patient.

[0021] Before describing several exemplary embodiments of the present disclosure, it should be understood that the present disclosure is not limited to the details of the structures or process steps set forth in the following description. The present disclosure is capable of having other embodiments and of being practiced or carried out in various ways.

[0022] In the present disclosure, and following convention, the distal end of a device is the end closest to the patient, while the proximal end of the device is the end farthest from the patient and closest to the practitioner.

[0023] Regarding the terms used in the present disclosure, the following definitions are provided. As used herein, the use of "a", "an", and "the" includes the singular and the plural.

[0024] As used herein, the term "Luer connector" refers to a connection collar that is the standard way to attach syringes, catheters, needles with fittings, IV tubing, etc. to each other. A Luer connector consists of male and female interlocking tubes that are slightly tapered to hold together even better by a simple press / twist fit. Luer connectors can optionally include additional threaded outer rims to make them more secure. The male end of a Luer connector is typically associated with a flush syringe or a drug administration syringe and can interlock and connect to the female end located on a vascular access device (VAD) or on a subcutaneous injection needle fitting. A Luer connector also has a distal end channel and a proximal end channel, where the distal end channel releasably attaches the Luer connector to the fitting of the VAD, and the proximal end channel releasably attaches the Luer connector to the barrel of a syringe.

[0025] As used herein, ISO 80369-7:2016 defines the specifications of a standard Luer connector that includes a 6% taper between the distal end and the proximal end. A male standard Luer connector increases from the open distal end towards the proximal end. A female standard Luer connector decreases from the open proximal end towards the distal end. According to ISO 80369-7:2016, the outer profile diameter of a male standard Luer connector measured at 0.75 mm from the distal end of the tip is between 3.970 mm and 4.072 mm. The length of the tapered portion of a male standard Luer connector is between 7.500 mm and 10.500 mm. The outer profile diameter measured at 7.500 mm from the distal end of the tip is between 4.376 mm and 4.476 mm. As used herein, the phrases "male standard Luer connector" and "female standard Luer connector" shall refer to connectors having the dimensions described in ISO 80369-7, which is hereby incorporated by reference in its entirety.

[0026] Those skilled in the relevant art will readily understand that although descriptive terms such as "tip", "fitting", "thread", "protrusion / insert", "tab", "bevel", "wall", "top", "side", "bottom", etc. are used in this specification for ease of understanding, they are not intended to limit any of the components that can be used in combination or alone to implement the various aspects of the embodiments of the present disclosure.

[0027] The content illustrated in this specification is intended to assist in a comprehensive understanding of the exemplary embodiments of the present disclosure. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. In addition, descriptions of well-known functions and structures are omitted for clarity and conciseness.

[0028] In an exemplary implementation of an embodiment of the present disclosure, Figures 1-3 syringe 10 is depicted. Syringe 10 includes a syringe barrel 12 having a proximal end 14 and a distal end 16. A plunger 18 and an associated plunger stopper 20 are inserted into the proximal end 14 of syringe barrel 12. A syringe cavity 21 is defined between the distal end 16 of syringe barrel 12 and the distal end of plunger stopper 20. A male Luer connector 22 on the distal end 16 of syringe barrel 12 is in fluid communication with syringe cavity 21. A Luer needle adapter 24 is coupled to male Luer connector 22 and is also in fluid communication with syringe cavity 21. A hollow syringe needle 26 has a proximal end coupled to Luer needle adapter 24 and a sharp distal opening needle tip 28 for subcutaneous puncture of a patient. Distal opening needle tip 28 is in fluid communication with syringe cavity 21 via a lumen defined within hollow needle 26.

[0029] Referring to Figure 2 and Figure 3 , needle cap 30 has a hollow tubular body 31, the proximal end 32 of which includes a radially outwardly projecting gripping flange 33. A first inner wall surface 34 of hollow tubular body 31 defines a first cavity portion 35 having an end opening and a female Luer-tapered profile. First inner wall surface 34 is coupled to the outer surface of needle adapter 24 in a mutually sliding and frictionally engaging manner. In other embodiments, the first inner wall surface defines an internal female thread of a threaded Luer connector that engages a corresponding male thread of a threaded Luer adapter. The inner wall of hollow tubular body 31 defines a neck portion 36 distal to its first inner wall surface 34. The distal end of neck portion 36 within hollow tubular body 31 has an inner wall surface 38 of reduced diameter, which in turn defines a proximal second portion 39 of the needle cavity and an inwardly projecting radial lip 40. The inner wall of hollow tubular body 31 further defines a filter cavity inner wall 42 and a filter retaining shoulder 44 distal to radially projecting lip 40.

[0030] The porous needle filter 46 is positioned within the inner wall 42 of the filter cavity between the radially inwardly projecting lip 40 and the filter retaining shoulder 44. The needle filter 46 has an outer diameter surface 48 that sealingly engages the inner wall 42 of the filter cavity. The needle filter 46 defines a partial through-hole 50 in its proximal axial end 52, which does not penetrate the distal axial end 54 of the needle filter and / or is not in communication with the distal axial end 54 of the needle filter. The partial through-hole 50 receives and captures the syringe needle 26 therein and has an inner diameter surface that sealingly engages the outer surface of the syringe needle. The open needle tip 28 remains captured within the partial through-hole 50 of the needle filter 46 and is in fluid communication with the open distal cap tip 56 of the needle cap 30 only when fluid migrates through the porous filter material. Thus, the porous filter material prevents contaminants within the drug payload from entering the open needle tip, the needle lumen, and ultimately the syringe cavity 21. The needle filter 46 divides the inner cavity of the needle cap 30 into a proximal second portion 39 defined between its proximal axial end 52 and a first cavity portion 35, and a distal third portion 60 defined between its distal axial end 54 and the open distal cap tip 56 of the needle cap. In Figures 1-4 the syringe embodiment of, the needle filter 46 is a separate component comprising a porous elastomeric material.

[0031] The potentially contaminated drug payload aspirated through the open distal cap tip 56 enters only the distal third portion 60 of the needle cap 30 and flows through the distal end 54 of the needle filter 46. After the drug passes through the filter 46, it is no longer contaminated; it is aspirated through the open needle tip 28 and ultimately into the syringe chamber 12 of the syringe 10. The needle filter 46, which sealingly engages the inner wall 42 of the filter cavity and the outer diameter of the syringe needle 26, prevents fluid leakage into the proximal second cavity portion 39 and the first cavity portion 35 of the needle cap 30 so that the aspirated drug is not trapped and wasted within the needle cap. In some embodiments, the so-called "dead space" volume within the third distal cavity portion 60 of the needle cap 30 is minimized to minimize waste of the aspirated drug. During aspiration of the syringe 10, the filter 46 aspirates the drug through it only under negative pressure from its proximal axial end 52 to its distal axial end 54, so that the drug does not leak from the syringe when no aspiration is being performed.

[0032] Refer to Figure 3 and Figure 4 The outer surface profile of the needle cap 30 forms a tapered, frustoconical distal end 62 that terminates in the open distal cap tip 56. In other embodiments, the tapered distal end includes other tapered polygonal profiles that terminate in the open distal cap tip.

[0033] In Figure 1 、 Figure 2 andFigure 4 Shown therein is a selectively removable needle shield 64 that is coupled to the distal end of the needle cap 30 and covers the distal end of the needle cap 30. The needle shield 64 has a proximal open end 66 and a blunt closed end 68 at its distal end. The needle shield 64 seals the open distal cap end 56 to prevent foreign matter from entering the needle cap 30 and the syringe 10; its blunt end 68 also prevents accidental piercing of the sterile syringe package, which could occur if the tapered distal end 62 of the syringe were not covered by the needle shield.

[0034] As Figure 5 Shown, the tapered distal end 62 of the end of the needle cap 30 facilitates direct drug withdrawal from the drug vial 70 while the syringe needle remains in place within the needle cap. The tapered distal end 62 of the needle cap 30 pierces the septum 72 of the drug vial 70 and reaches the bottom 74 of the vial to draw the drug 76 or other medical fluid (such as a saline flush solution) directly into the syringe 10. The tapered distal end 62 of the needle cap 30 allows its open cap end 56 to draw all of the drug from the corner of the vial bottom 74. The smooth, tapered distal end 62 of the needle cap 30 reduces the likelihood of particulate matter from a damaged vial septum 72 penetrating into the vial, which particulate matter could contaminate the drug 76 if the sharp syringe needle tip were used directly to withdraw the drug from the vial 70. The needle filter 46 filters and blocks any vial septum material and glass fragments within the drug payload of the vial. Advantageously, when the needle cap 30 covers the syringe needle, it also protects the syringe needle from bending or protects the needle tip from damage by reflective contact. After the desired amount of drug has been withdrawn into the syringe chamber, the healthcare practitioner removes the needle cap 30 to expose the injection needle of the syringe for subsequent injection of the patient. Since the needle and needle interface remain attached to the syringe during the process of withdrawing the drug into the syringe, handling of the exposed, sharp injection needle is minimized.

[0035] In contrast, in the absence of using the filtered needle cap 30 of the present disclosure, a healthcare practitioner performing a patient drug administration protocol would need to perform a two-stage process. As previously described, the practitioner would first attach a blunt fill needle (with or without an internal filter element) to the exposed syringe Luer connector, either by first removing the associated injection needle of the syringe or using a syringe without an injection needle. After the blunt fill needle is attached, the healthcare practitioner withdraws the drug from the vial into the syringe chamber. In the second stage, the practitioner then replaces the blunt fill needle with an injection needle in order to administer the drug to the patient. In the two-stage administration process (as opposed to the single-stage process using the syringe 10 with the needle cap 30 of the present disclosure), the use of a separate, known blunt fill needle requires additional syringe preparation steps, thereby increasing the likelihood of administration errors and potential sterility compromises.

[0036] Figure 6 Depicts another embodiment of the cap of the present disclosure. The cap 130 is coupled to the syringe interface 24, its hypodermic needle 26, and the sharp needle tip 28. The cap 130 has a hollow tubular body 131, the proximal end 132 of which includes a radially outwardly protruding gripping flange 133. The first inner wall surface 134 of the hollow tubular body 131 defines a first cavity portion 135 having an end-opening, female Luer-tapered profile. The first inner wall surface 134 is coupled to the outer surface of the needle interface 24 in a mutually sliding, frictionally engaging manner. In other embodiments, the first inner wall surface defines the internal female threads of a threaded Luer connector that engage the corresponding male threads of a threaded Luer interface. The inner wall of the hollow tubular body 131 defines a neck portion 136 distal to its first inner wall surface 134. The distal end of the neck portion 136 within the hollow tubular body 131 has an inner wall surface 138 of reduced diameter, which in turn defines a proximal second portion 139 of the needle cavity and a radially inwardly protruding lip 140. The inner wall of the hollow tubular body 131 further defines a filter cavity inner wall 142 and a filter retaining shoulder 144 distal to the radially protruding lip 140.

[0037] The porous needle filter 146 is positioned within the filter cavity inner wall 142 between the radially inwardly protruding lip 140 and the filter retaining shoulder 144. The needle filter 146 has an outer diameter surface 148 that seals against the filter cavity inner wall 142. The sharp needle tip 28 pierces the interior 150 of the needle filter at the proximal axial end 152 of the needle filter 146, but the tip does not pierce the distal axial end 154 of the filter. The filter interior portion 150 receives and captures the sharp tip 28 of the syringe needle 26 therein and seals against the outer surface of the syringe needle. The open needle tip 28 remains captured within the interior 150 of the needle filter 146 and is in fluid communication with the open distal cap tip 156 of the cap 130 only when fluid migrates through the porous filter material. Thus, the porous filter material prevents contaminants within the drug payload from entering the open needle tip, the needle lumen, and ultimately the syringe cavity 21. The needle filter 146 divides the inner cavity of the cap 130 into a proximal second portion 139 defined between its proximal axial end 152 and the first cavity portion 135 and a distal third portion 160 defined between its distal axial end 154 and the open distal cap tip 156 of the cap. In Figure 6 the syringe embodiment, the needle filter 146 is a separate component comprising a porous elastomeric material.

[0038] Figure 7Depicts another embodiment of the cap of the present disclosure. The cap 230 is coupled to the syringe interface 24, its hypodermic needle 26, and the sharp needle tip 28. The cap 230 has a hollow tubular body 231, the proximal end 232 of which includes a radially outwardly projecting gripping flange 233. The first inner wall surface 234 of the hollow tubular body 231 defines a first cavity portion 235 having an end-opening, female Luer-tapered profile. The first inner wall surface 234 is coupled to the outer surface of the needle interface 24 in a mutually sliding, frictionally engaging manner. In other embodiments, the first inner wall surface defines the internal female threads of a threaded Luer connector that engage the corresponding male threads of a threaded Luer interface. The inner wall of the hollow tubular body 231 defines a neck portion 236 distal to its first inner wall surface 234. The distal end of the neck portion 236 within the hollow tubular body 231 has an inner wall surface 238 of reduced diameter, which in turn defines a proximal second portion 239 of the needle cavity and an inwardly projecting radial lip 240. The inner wall of the hollow tubular body 231 further defines a filter cavity inner wall 242 and a filter retaining shoulder 244 distal to the radially projecting lip 240.

[0039] The porous needle filter 246 is positioned within the filter cavity inner wall 242 between the inwardly projecting radial lip 240 and the filter retaining shoulder 244. The needle filter 246 has an outer diameter surface 248 that is sealingly engaged with the filter cavity inner wall 242. The sharp needle tip 28 abuts and is biased against the needle filter 246, thereby forming a recess 150 at the proximal axial end 252 of the needle filter, but the tip does not pierce the distal axial end 254 of the filter. The proximal axial end 252 of the needle filter 246 receives and captures the sharp tip 28 of the syringe needle 26 at its recess 250 and is sealingly engaged with the outer surface of the syringe needle. The open needle tip 28 remains in a biased, sealing engagement against the proximal axial end 252 of the needle filter 246 and is in fluid communication with the open distal cap end 256 of the cap 230 only when fluid migrates through the porous filter material. Thus, the porous filter material prevents contaminants within the drug payload from entering the open needle tip, the needle lumen, and ultimately the syringe cavity 21. The needle filter 246 divides the internal cavity of the cap 230 into a proximal second portion 239 defined between its proximal axial end 252 and the first cavity portion 235 and a distal third portion 260 defined between its distal axial end 254 and the open distal cap end 256 of the cap. In Figure 7 the syringe embodiment, the needle filter 246 is a separate component comprising a porous elastomeric material.

[0040] The needle cap 230 includes a needle support ring 261 to inhibit potential bending or radial offset of the needle 26 when the needle 26 abuts against the proximal end 252 of the needle filter 248. The needle support ring 261 is selectively axially positioned within the needle cap 230 along the length L of the needle 26. The needle support ring 261 defines an internal annular surface 262 that is spaced from the outer circumferential surface of the needle 26. In other embodiments, the internal annular surface 262 is in sealing engagement with the outer circumferential surface of the needle 26 to form a second seal to prevent drug migration into the proximal second portion 239 of the needle cavity. The needle support ring 261 is retained within the needle cap 230 by a first radial lip 264 and a second radial lip 266. In other embodiments, the needle support ring is integrally formed within the needle cap 230.

[0041] The embodiments of the syringe and syringe needle cap disclosed herein are made of medical-grade materials known to those skilled in the art. In some embodiments, the barrel, plunger, and rod are made of polypropylene, polyethylene, or polycarbonate polymers. In some embodiments, the stopper is made of polyisoprene polymer or other known elastomers.

[0042] In some embodiments, the needle filters 46, 146, 246 are formed as cylinders that are press-fitted into their corresponding needle caps and are radially compressed against the inner walls of the needle caps. In other embodiments, such as Figure 4 the needle filter 46, the filter is preformed into a desired profile. In some embodiments, the needle filter is made of a porous polymer, such as an elastomer having a Shore A hardness of 30 - 70, where the filtration efficiency is optimized to filter out particles larger than 5 μm. In some embodiments, the needle filter is manufactured by blowing air or a foaming agent during an injection molding or thermoforming process, such as microcellular injection molding. In other embodiments, the needle filter is manufactured by preferential dissolution or precipitation of mixed particles, such as salts. In other embodiments, the needle filter is manufactured by thermal welding, laser welding, or ultrasonic welding or sintering of polymer materials. Exemplary polymer materials include, but are not limited to, polypropylene, polyethylene, and polystyrene particles.

[0043] Throughout the specification, references to "one embodiment", "certain embodiments", "various embodiments", "one or more embodiments", or "embodiments" mean that the particular features, structures, materials, or characteristics described in connection with the embodiments are included in at least one embodiment of the present disclosure. Thus, phrases such as "in one or more embodiments", "in certain embodiments", "in various embodiments", "in one embodiment", or "in embodiments" that appear throughout this specification are not necessarily referring to the same embodiment of the present disclosure. Moreover, in one or more embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner.

[0044] Although the disclosure herein has been provided with reference to specific embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the present disclosure. It will be apparent to those skilled in the art that various modifications and variations can be made to the present disclosure without departing from the spirit and scope of the present disclosure. Accordingly, the present disclosure is intended to cover modifications and variations that fall within the scope of the appended claims and their equivalents.

Claims

1. A syringe, comprising: a syringe barrel having a proximal end and a distal end and a syringe cavity therein; a plunger and an associated plunger stopper in the proximal end of the syringe barrel; a male Luer connector on the distal end of the syringe barrel, the male Luer connector being in fluid communication with the syringe cavity; a Luer needle adapter coupled to the male Luer connector, the Luer needle adapter being in fluid communication with the syringe cavity; a hollow syringe needle having a proximal end coupled to the Luer needle adapter and in fluid communication with the syringe cavity, and a distal open needle tip; a needle cap having a tubular body with an inner wall surface that defines a cap inner cavity therein, the cap inner cavity capturing the distal open needle tip, the inner wall surface further defining a first cavity portion at the proximal end of the tubular body that is end - opening and has a female Luer - tapered profile, the first cavity portion being coupled to the needle adapter, and the inner wall surface defining an open cap tip at the distal end of the tubular body; a fluid - permeable needle filter within the cap inner cavity, the fluid - permeable needle filter having a distal end facing the open cap tip and a proximal end in fluid - tight contact abutting the open needle tip, the needle filter dividing the cap inner cavity into a second proximal portion and a third distal portion that are separated from each other, the needle filter capturing particulate matter in the fluid drawn through the hollow syringe needle into the syringe cavity while preventing fluid flow through it from flowing from the third distal portion of the hollow cavity outside the hollow syringe needle into the second proximal portion of the hollow cavity; and the tubular body having a tapered, frustoconical outer surface profile at its distal end that terminates in the open cap tip.

2. The syringe according to claim 1, further comprising, wherein the proximal end of the needle filter defines a partial - depth through - hole that is not in communication with the distal end of the needle filter, and the needle tip is captured within the partial - depth through - hole of the filter and is sealingly engaged with the partial - depth through - hole of the filter.

3. The syringe according to claim 1, further comprising, wherein the needle tip pierces and penetrates the proximal end of the needle filter but does not penetrate the distal end of the needle filter.

4. The syringe according to claim 1, further comprising, wherein the needle tip abuts and compresses the proximal end of the needle filter and is sealingly engaged with the proximal end.

5. The syringe according to claim 1, wherein the inner wall surface of the tubular body defines a radially inwardly - directed lip that abuts the proximal end of the needle filter and a retaining shoulder that abuts the distal end of the needle filter.

6. The syringe according to claim 1, wherein the tubular body defines a neck portion of reduced diameter between its female Luer - tapered profile cavity portion and its tapered frustoconical distal end, and the needle filter is positioned distal to the neck portion.

7. The syringe according to claim 1, wherein the proximal end of the tubular body is defined by a gripping flange that protrudes outward.

8. The syringe according to claim 1, wherein the inner wall surface of the first cavity portion defining the inner cavity of the cap further includes a female luer slip connector that mates with a corresponding male luer slip connector of the needle interface.

9. The syringe according to claim 1, wherein the inner wall surface of the first cavity portion defining the inner cavity of the cap further includes a female threaded luer connector that mates with a corresponding male threaded luer connector of the needle interface.

10. The syringe according to claim 1, further comprising a needle guard that is coupled to the distal end of the tubular body of the needle cap and seals the open end of the needle cap.

11. The syringe according to claim 1, wherein the needle filter is capable of filtering out particles having a size greater than or equal to 5 μm that are entrained in the fluid withdrawn into the needle cap.

12. The syringe according to claim 11, wherein the needle filter is radially compressed within the inner wall surface of the needle cap.

13. The syringe according to claim 12, wherein the needle filter comprises a porous polymer that is made by a process selected from the group consisting of injection molding or sintering with a foaming agent.

14. The syringe according to claim 11, wherein the needle filter comprises a porous polymer that is made by a process selected from the group consisting of injection molding or sintering with a foaming agent.

15. The syringe according to claim 1, wherein the needle filter comprises a porous polymer that is made by a process selected from the group consisting of injection molding or sintering with a foaming agent.

16. The syringe according to claim 15, wherein the needle filter comprises an elastomer having a Shore A hardness of 30 - 70 that is capable of filtering out particles having a size greater than or equal to 5 μm that are entrained in the fluid withdrawn into the needle cap.

17. The syringe according to claim 1, further comprising a needle support ring that is coupled to the inner wall surface of the needle cap and is axially positioned within the needle cap along the length of the needle, the needle support ring defining an inner annular surface that is radially opposed to the outer circumferential surface of the needle.

18. The syringe according to claim 17, wherein the inner annular surface of the needle support ring is in sealing engagement with the outer circumferential surface of the needle.

19. A syringe comprising: a syringe barrel having a proximal end, a distal end, and a syringe cavity therein; a plunger and an associated plunger stopper in the proximal end of the syringe barrel; a male luer connector on the distal end of the syringe barrel that is in fluid communication with the syringe cavity; a luer needle interface coupled to the male luer connector that is in fluid communication with the syringe cavity; A hollow syringe needle having a proximal end fluidly connected to the Luer needle fitting and in fluid communication with the syringe cavity, and a distal open needle tip; A needle cap having a tubular body with an inner wall surface defining a cap inner cavity therein, the cap inner cavity capturing the distal open needle tip, the inner wall surface further defining a first cavity portion of an end-opening, female Luer-tapered profile on the proximal end of the tubular body, the first cavity portion being connected to the needle fitting, and the inner wall surface defining an open cap tip, a retaining shoulder axially spaced from the open cap tip, and a radially inwardly directed lip axially spaced from the retaining shoulder on the distal end of the tubular body; A fluid-permeable needle filter of a porous polymer structure within the cap inner cavity, the needle filter being inserted between the retaining shoulder and the radially inwardly directed axial lip, having a distal end facing the open cap tip and a proximal end defining a partial-depth through-hole that does not communicate with the distal end of the filter, the needle tip being captured within the partial-depth through-hole of the filter and sealingly engaged with the partial-depth through-hole of the filter, the needle filter dividing the cap inner cavity into a second proximal portion and a third distal portion separated from each other, the needle filter capturing particulate matter in the fluid drawn into the syringe cavity through the hollow syringe needle while preventing the fluid flow therethrough from flowing outside the hollow syringe needle from the third distal portion of the hollow cavity into the second proximal portion of the hollow cavity; and The tubular body has a tapered, frustoconical outer surface profile at its distal end that terminates in the open cap tip.

20. A syringe comprising: A syringe barrel having a proximal end, a distal end, and a syringe cavity therein; A plunger and an associated plunger stopper in the proximal end of the syringe barrel; A male Luer connector on the distal end of the syringe barrel, the male Luer connector being in fluid communication with the syringe cavity; A Luer needle fitting connected to the male Luer connector, the Luer needle fitting being in fluid communication with the syringe cavity; A hollow syringe needle having a proximal end fluidly connected to the Luer needle fitting and in fluid communication with the syringe cavity, and a distal open needle tip; A needle cap having a tubular body with an inner wall surface defining a cap inner cavity therein, the cap inner cavity capturing the distal open needle tip, the inner wall surface further defining a first cavity portion of an end-opening, female Luer-tapered profile on the proximal end of the tubular body, the first cavity portion being connected to the needle fitting, and the inner wall surface defining an open cap tip, a retaining shoulder axially spaced from the open cap tip, and a radially inwardly directed lip axially spaced from the retaining shoulder on the distal end of the tubular body; A fluid-permeable needle filter of a porous polymer structure within the inner cavity of the cap, the needle filter being inserted between the retaining shoulder and the radially inwardly directed axial lip, having a distal end facing the open cap end and a proximal end, the needle tip piercing and penetrating the proximal end of the needle filter and sealingly engaging with the proximal end of the needle filter, the needle filter dividing the inner cavity of the cap into a second proximal portion and a third distal portion separated from each other, the needle filter capturing particulate matter in the fluid drawn into the syringe cavity through the hollow needle while preventing the fluid flow therethrough from flowing from the third distal portion of the hollow cavity to the second proximal portion of the hollow cavity outside the hollow syringe needle; and The tubular body has a tapered, frustoconical outer surface profile at its distal end, which terminates in the open cap end.

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