This invention relates to a self-sealing septum device, ore particularly: II relates to a self-sealing septum device for use with a needle based sampling system, Cross-Reference to Related Applications

The present application claims the benefit of priority of European Patent Application No. 1.229007(17, filing dale March 1, 2012, incorporated by reference erein in its entirety, BACKGROUND OF THE INVENTION

The current state of the art for sampling systems used for biological manufacture such as bioreaetors, storage ta ks, downstream processing equipment such as filtration equipment Is a system based on a sampling needle that pierces a se tum,

Those systems are well-known such as the NovaSeptum# sampling device available from illlpore Corporation and are shown in US 6, 032, 543 and US 2011/0155258 At Such a system and lis components are shown in Figures 1-3.

The s stem 2 has a front piece 4 which attaches to tie vessel 6 or a fitting on a pipe or piece of equipment that contains a liquid 3 to be sampled. The system 2 Is connected to the vessel 8 and the like via a NAConnecf® flange available from Milllpore Corporation or a Tr!- Clover Φ clamp or other such, well-known means for attaching one component !o another. ^' Trie front piece has a front face S, with one or more openings 10 extending through it from the front face 8 to a back face 12. The front piece 4 may a e depressions 11 formed on the hack faca 12 to center the septum 20 of the sampling system 2.The front piece 4 also has a central attachment extension 14 extending outwardly from the back face 12 In a direction away from the front face 8. A housing 16, containing one or more shafts 18 for holding a septum 20 and a noodle 22 and a central shaft 15 for he central attachment extension 14 and the housing 16 is attached to the hack face 12 of the front piece 4 and the shafts IS are In alignment with the one or more openings 10 on the back face 12 of the f ont piece 4, The needle 22 has a hollow lumen 21. A septum 20 is held against opening 10 of the back face by the housing 16 and the attachment means 24 and the central shaft 14. The needle 22 is located in the shaft 18 behind the septum 20, The rear portion 23 of the needie 22 has a first end 25 of a conduit 26 attached to it. The other end 2? of the conduit 26 is attached to a sample bag 28 for holding a sample withdrawn from the vessel 6 by trie system 2. The needle 22 has a trigger 30 to actuate It and move it forward and backward in Ihe shaft 18. T e shaft 18. housing 16 and /or trigger 30 limits the travel of Ihe needle 22

in use the system is assembled by placing a septum 20 against each opening 10 on the back face 12 of the front piece 4. A needle 22 is located behind the septum 20 and ihe housing 16 is attached to the central attachment extension 14 and attachment means 24 to compress the septum 22 against the back face 12 to form a liquid tight seal with the opening 10. The front piece 4 is attached to the vessel β and then the vessel 6 is steamed to sterile it before use. At the same time the surface of the septum 22 facing the opening 10 Is also steam sterilized.

Whan one wishes to take a sample, the needle 22 Is moved forward, piercing the septum 20 and allowing liquid In the vessel 6 to flow through the lumen 21 to the conduit 26 and Info the sample bag 28. When the sample has been taken, the needle 22 is moved back through the septum 20, As the septum 20 is under compression, the hole created by the needle 22 is dosed by the pressure applied to the septum: 20 by the assembled system 2. The conduit 26 is cut so that the sample bag 28 can be further processed as desired. The vessel is eventually drained and the vessel and face of the device including the surface of the septum 22 over the opening 10 are again steam sterilized to kill any remaining biological matter that remains.

Generally, the hole in the septum 22 created by the needle 20 piercing the septum 22 remains seated both white the septum is compressed by the system 2 and even after the system 2 has been disassembled.

However there Is always the concern that the hole does ml remain sealed and that some leakage of ihe fluid Ihe needle 22 and the remaining portion of the conduit 26 will occur. This would be considered e bkteard and could cause some safely and product contamination Issues

The present invention overcomes these concerns.

SUMMARY OF THE INVENTIO

The present invention relates to a self-seating septum that seals the hole created by the piercing of the septum by ihe needle.

The self-sealing septum can be a material contained within the septum which seals the hole by itself. It can alternatively be a material which cures upon the exposure of that material to heat or steam. Alternatively, It can bo a la er of sealing material located between Ihe septum and the needle rather than being within the septum teeft A firs! embodiment of t e present invention is a sampling device having a septum in which a layer of self sealing material Is encapsulated within the thickness of the septum such thai the needle of the device passes through or pierces the layer when it is moved toward and away from the vessel during a sample taking procedure. The self sealing material seals the hole created by the movement of (he needle through the septum creating a liquid tight seal in the septum after the needle has been used.

A second embodiment Is to use a separate layer of self sealing material placed between the firs! surface of the septum and the needle when the needle Is In lis retracted position. The self sealing material seals the piercing of the septum created by the movement of the needle through the septum creating a liquid tight seal m the septum after the needle has been used and retracted behind the septum.

A third embodiment Is to use either the first or second embodiment in a sampling system such as is taught by US 6, 032, 543 or US 2011/0155258 At .

A further embodiment of the present invention is to provide a self sealing material that doesn't interfere with the movement of the needle through the septum, that is compatible with the material of the septum and which provides a good liquid tight seal of the piercing caused by the travel of the needle through the septum, even when there is no compressive force applied to one or more sides of the septum. Such materials Include but are not limited to silicone gels and low Shore durometer silicones such as a silicone with a Shore of less than 40, preferably less than 35, more preferably with a Shore between 10 and 35 and most preferably between 20 and 35; elastomerlc thermoplastics, other rubbers such as nitiile rubber, rubbery thermoplastics such as siyrene block copolymers and various thermosels such as poiyurethane,. The self- sealing septum can be a material contained within the septum which seals the piercing by itself. It can alternatively be a material which cures upon the exposure of thai material to heat or steam.

Another embodiment Is to use a tow Shore A durometer (less than 40, preferably 10-30 and more preferably 10-20 Shore A durometer) as the sealing material.

IN THE DRAWINGS

Figure 1 shows a partial cross section partial planer view of a septum based sam ling system.

Figure 2 shows an exploded view of a portion of the sampling system of the prio art. Figure 3 shows a septum and needle of the sampler system of the prior art in cross- sectional view. igure 4 sho s a first embodiment of a septum and needle of the sampler system of the present invention in cross-sectional view.

Figure 5 shows a second embodiment of a se tum and nee le of the sampler system of the present invention in cross-sectional view,

DETAILED DESCRIPTION OF THE INVENTION

Figure 4 shows a first embodiment of the present invention. To the extent that the elements are the same the same reference numbers wl be used to identify them.

In this embodiment the septum 20 hes a region containing self sealing material 30. The region 30 s located inwardly of either the first surface 32er the second surface 34 of the septum 20 so that the needle 2.2, as it pierces the septum 20, travels through the region 30 both on its way pest the second surface 34 and again as it retracts toward the first surface 32, The material contained within this region 30 effectively seats the piercing of the septum material left b the needle 22 in its travels through the septum 20 ensuring a good liquid tight seal.

Figure 5 is a second embodiment of the present Invention and simitar in most ways to that: of Figure 4 except that in this instance the needle 22 is not starting from a position of being within a portion of the septum 20 in its retracted position. Rather it is with in a channel 36 and kept above the first surface of the septum until it is moved through the septum and both surfaces of the septum to draw a sample. As with the first embodiment the materiel contained within this region 30 effectively seals the piercing of the septum material left by the needle 22 in its travels through the septum 20 ensuring a good liquid tight seal.

Figure 8 shows another embodiment of the present invention for use with a system of US 2011/0155258 At. in this Instance the septum can be a separate piece retained on the back face of the front piece. The septum 20 Has a channel 36 like thai of Figure 5 in which the needle 22 resides in Its refracted position above the first surface 32. it works in the same way as that of Figures 4 and 5.

Figure 7 shows another embodiment that may fee used with either embodiment of Figures 5 or β. The self sealing material 30 instead of being formed within the septum material Is a separate pad 38 that is inserted into the channel 36 so that if is located adjacent the first surface 32 of the septum 20. The needle 22 Is located adjacent the pad of material 38 and travels through the pad 3θ and the septum 20 as it moves to Its active position beyond the second face 34 of the septum 20. When the needle 22 returns to Its retracted position the material of the pad 38 ensures a liquid tight seel Is formed. The self sealing material may be any material that doesn't interfere with the movement of the needle 22 through the septum 20, that is compatible with the material of the septa 20 and which provides a good liquid tight seal of the piercing caused by the travel of the needle 22 through the septum 20, even when mere is no compressive force applied to one or more sides of the septum, Such materials include but are not limited io silicone gels and low Snore urometer silicone such as a silicone with a Shore of less than 40, preferably less than 35, more preferably with a Shore between 10 and 35 and most preferably between 20 and 35. One SUCh material is Siiparsn® low shore (ex 10 shore A). Another is a silicone get such as Dow Corning d!siectric gels. A further materia! can be an etasmmeric therrnopiasfcs such as Sanioprene® elastome available from Advanced Elastomer Systems LP. other ubbe s such as mtriie rubber, various thermosets such as po!yyreth rte or rubbery thsrmopiastiss such as various styrene block copolymers and the like can Pa used so long as they have the ability to seal hie hole in the material caused by the passage of tne needle through the materia!.

The self-sealing septum can be a material contained within the septum which seals the hole by itself, if can alternatively be a material which cures upon the exposure of that material to heat or steam. Alternatively it can be a layer of sealing material located between the septum and the needle rather than being within the septum itself.

The needle can be a hollow needle having a lumen running through at least a portion of it to a position at which the conduit is attached. The needle may have a sharp hollow point at its front end as shown In Figure 4, The lumen Is exposed from the front of the needle Io the point at which it Is connected to the conduit in such an embodiment. Alternatively _. ; the needle have a sharp closed point with an opening formed along a portion of Its length which extends through the septum In use to allow liquid to flow Into the lumen and then on io the conduit attached to a rearward portion of the needle.

In practice, the septum of Figures AS is formed with the sealing material encapsulated within It. This can be accomplished by a variety of methods such as overmoldlng and infection molding. Alternatively, one can form a septum with a closed second surface and an open first surface and a cavity positioned between the second surface and the open first surface into which is injected the sealing material The first surface is then closed by molding additional septum material over the cavity,

in practice, th -septum of Figure 7 is formed with the sealing material being a separate pad that is inserted into the channel so that It is located adjacent the first surface of the septum. This pad can be formed by a variety of methods. For example, one car? simply form a disk of material that has been cured sc as if can be bandied and simply Inserted Info the channel One can form a sheet of silicons or silicone gel and punch out a piece that fits into the channel and simply insert the pad and retain it by a friction fit Alternatively: one can add the material to the channel after septum formation and allow the malarial to cure in place forming the desired layer adjacent the first surface of the septum and the needle in its retracted position when the septum is assembled into a sampling device.

Prophetic Example

A septum device according to US 0, 032, §43 is formed with an encapsulated self sealing layer of tew durometer SilpUfan ; shore A of 10 durdmeter formed as shown in Figures 4-8, The septum has a tube at the rear portion of e need e connected to a sample? bag. The septum is loaded into s fcovaSeptum* holder of US 6, 032, 543 which is attached to trie side of a stainless steel ves el via a AConneci® flange available from fvtiipore Corporate of Bi hea, Massachusetts,

The face of the Pokier and the septum are steam sterilized along with the interior of the vessel. Water is added to the vessel to a level higher than that of the septum device.

The needle Is moved to pierce the septum and take a sample fro the vessel. The sample flows through Ihe needle ^' s lumen into the tube and then the bag. The needle Is then withdrawn back through the sep!urn to its closed position. The septum is then checked for leaks and none are found. The bag is then removed as described in US 6, 032 _; 543 using a

NovaSeaF hand crim er available from iliipore Corporation of Bierica, Massachusetts,

The tank is drained and the septum device removed from the holder. No wafer is found to leak through the septum even when pressure is applied to tie water in the bag,