Pipette tip for ventilated transfer

Abstract

The present invention relates to a pipette tip (30) for manually, semi-automatically or automatically actuated pipetting, intended to be inserted through a septum (26) into a container (20) in order to collect and inject a liquid (20), characterized in that the pipette tip (30) has one or more axial fins (37) on the outer surface of an insertion section (33), the section (33) being referred to as the finned section, allowing air to flow in or out of the container (20) during a fluid transfer process such as pipetting.

Description

VENTILATED PIPETTE TIP FOR TRANSFER Object of the invention

[0001] The present invention relates to a device for dispensing and transferring liquids from a container. More specifically, the invention relates to the improvement of pipetting systems, automated or not, intended for the handling and transfer of precise volumes of liquids. The invention relates to a pipette tip enabling the precise transfer of liquid from or into any container in a closed environment. State of the

[0002] In the field of pharmaceutical preparations and quality control, ingredients are commonly supplied in containers. A liquid product contained in a container is typically withdrawn using a syringe fitted with a needle or pipette tip, a manual or automatic pipette filler with a pipette tip, or by pressure differential to a third-party device: a preparation device, a chemical synthesis apparatus, etc. Common applications include dosing, mixing, fractionating the product, or taking a sample.

[0003] Products are frequently withdrawn from containers that are either open or sealed with a pierceable septum (flexible stopper, liner, film, etc.). In the case of containers sealed with a septum, access to the product is gained by piercing the septum with a needle, spike, or piercing pipette tip.

[0004] Pipette tips, referred to as "tips" in the text, are commonly made of molded plastic. They are hollow, vary in length, and are generally conical in shape. The upper / proximal end of the tip is sized to allow for a tight seal on the sampling device. The tip is open throughout, allowing liquid to be drawn into the tip and then transferred elsewhere. The lower / distal end of the pipette tip is shaped to pierce the septa of containers and to immerse in the liquid for sampling. The liquid is drawn into the tip and can be extracted by applying pressure upstream via the transfer device, pipette, or other. The tip can usually be ejected from the transfer device using a manual or automatic trigger.

[0005] US8163256B2 describes a conventional pipette tip shown in Figure 1. The pipette tip 1 has a tubular configuration with an upper section having an upper wall segment 4 surrounding a locking chamber 5 and a lower wall segment 6 forming a sealing zone 7. A body section 2 extends downward from the upper section 3 to a narrow-diameter open end 8. The lower wall segment 6 is provided internally with an inlet section 9 that narrows internally to a cylindrical section 10. The lower wall segment is reinforced by external ribs 11 that are equally distributed around the periphery and extend from the rim 9 to the body section 2. The lower ends 12 of the external vertical ribs 11 lie on a plane that delimits the lower part of the crown 3 from the body section 2. The external surface of the body section 2 is continuous, and smooth.

[0006] Document US8501118B2 presents another pipette tip, shown in Figure 2. Again, the outer surface of the pipette tip body 13, which is immersed in the flask, is continuous and smooth. These are known prior art features. The tip of the pipette tip 13, which is immersed in the flask, consists of a neck 14 and a body 15 with a change in taper to ensure sufficient capacity. The lower end of the body 15 has a small opening 17 through which the liquid is drawn into the body 15 and dispensed from the body 15 during the normal operation of the pipette. Support ribs 18, which serve to hold the tip 13 or a set of tips 13 in a tray or other for later use, as is known from the state of the art, extend downwards on the outer surface of the pipette tip 13 from the neck 14.

[0007] Documents US8287820B2 and WO2012 / 133605A1 provide further examples of pipette tips well known from the prior art. Again, the outer surface of the pipette body, in the part that dips into the container, is continuous, cylindrically symmetrical, and smooth.

[0008] The use of pipette tips with manual pipettes or automated liquid handling systems is well known. When such pipette tips are used to aspirate or inject liquid into an open container, there is no problem with liquid transfer, as shown in Figure 3. Liquid 21 is drawn by suction into a conventional pipette tip 19 using a pipette, and the space 23 between the pipette tip and the container 20 allows air to pass freely for optimal ventilation and instantaneous pressure equalization: P1 = P2 at all times. In Figure 3, reference numeral 24 indicates the vertical movement of the pipette to insert and remove the pipette tip from the container, and 25 shows the direction of aspiration and drainage of the liquid 22 drawn into and out of the conventional pipette tip 19 using a pipette fitted with said pipette tip 19.A pipette tip as known from the prior art 19 therefore provides a simple means of fluidic transfer of the contents of the container when it is opened.

[0009] However, when pipette tips of the type described in the state of the art 19 are used to draw or eject a liquid from or into a container equipped with any type of septum (liner, flexible stopper, film, etc.), a suction effect is observed due to continuous circumferential contact 27 between the septum 26 and the conventional tip 19, which ensures a more or less strong seal between the two elements (Figures 4 and 5). The level of sealing will depend on numerous factors such as dimensions, materials, surface finish, the fluid in question, etc. This sealing line 27 slows down or blocks gas exchange between the inside and outside of the container, generating a positive or negative pressure differential 28 between the inside and the exterior of the container according to the different pipetting phases described previously: - P1 > P2 (pressurization of the container's interior) occurs when the septum is pierced and the tip is immersed in the container. The positive pressure inside the container tends to push the liquid into the tip. - P1 < P2 (depressurization of the container's interior) during liquid dispensing and removal of the nozzle from the container. The negative pressure inside the container tends to draw the liquid out of the nozzle.

[0010] These pressure differences generate uncontrollable or difficult-to-control liquid flows between the tip 19 and the container 20, making precise liquid dosing complicated or impossible. Conventional pipette tips therefore have the disadvantage of being designed solely for accurately dispensing liquids into or from otherwise ventilated containers.

[0011] US2024 / 061003A1 discloses a pipette tip configured for aspirating and dispensing liquids. The pipette includes a tip with an opening and one or more blades extending at least partially from the tip. At least some of the blades have a sharp-angled cutting edge along their length. In some embodiments, the pipette tip is part of a detachable pipette tip comprising a tip body with a first end configured to detachably couple to a pipette.

[0012] US patent 2006 / 172433A1 discloses an apparatus and method for sampling liquids using a ribbed pipette tip for barrier penetration. The single disposable plastic pipette tip has an outer surface with at least three ribs extending longitudinally along the outer surface of the body. Each rib is circumferentially spaced at a uniform distance from the others, with each rib sized and positioned symmetrically on the pipette tip body. The pipette tip can be mounted on a handheld pipette stem or on the mounting head of an automated liquid handling machine. The pipette tip is sufficiently rigid and straight. to pierce a barrier foil or resilient barrier sealing a container containing a liquid to be sampled. The ribs on the pipette tip work to keep the barrier separate from the outer surface of the pipette tip so that ambient air can circulate in and out of the sealed container assembly during aspiration of the liquid sample into the pipette tip, allowing for accurate transfer of liquids while minimizing the risk of contamination.

[0013] US patent 2022 / 152604A1 discloses attachment devices for removable coupling to a fluid dispensing device. The attachment devices comprise a hollow body including a collar portion and a cylinder portion extending from the collar portion. The cylinder portion has an end portion with a closed end and at least one lateral opening. Positioned longitudinally along the outer surface of the cylinder is at least one rib branching upward into two rib branches. When coupled to a fluid dispensing device, the assembly can be used to obtain a fluid sample. The assembly can then be used to dispense the fluid sample into an analytical vessel for subsequent analysis. Objectives of the invention

[0014] The present invention aims to provide a pipette tip that does not have the disadvantages of the prior art.

[0015] The device of the invention is designed to allow the withdrawal of a precise quantity of liquid from any container closed by a septum. It also allows the optimal injection of a precise quantity of liquid into any container equipped with a septum. Main characteristic elements of the invention

[0016] The present invention relates to a pipette tip, referred to as the "tip," compatible with any form of pipette actuation, whether manual, semi-automatic, or automatic. The pipette tip is intended to be introduced into any container through a septum for the purpose of withdrawing and injecting a liquid. The container may be of any type, size, or shape, for example, a bottle, a test tube, a PCR plate well, or an optical cuvette. The septum may be of any shape, for example, a stopper, liner, adhesive film, heat-sealable film, or other, and of any material, for example, elastic or elastomeric material, natural or synthetic rubber, or plastic.

[0017] The pipette tip of the present invention has axial fins on the outer surface of its plunging section to ensure ventilation during the transfer of liquid to or from the container as well as during the movement of the tip in and out of the container.

[0018] In an innovative manner, said pipette tip has a tip end section or point, of a first conical and continuous shape, devoid of axial fins and provided with an orifice at the end of the cone and said pipette tip has a transition zone between the finned section and the tip end section, said transition zone being of a second conical shape and having an extension for each of said fins of the plunging section contributing to said ventilation, the angle of the first conical shape being smaller than the angle of the second conical shape.

[0019] According to preferred embodiments of the invention, the pipette tip further comprises at least one of the following features or a suitable combination thereof: - the finned section is located between a main reservoir of the nozzle and the tip equipped with an orifice; - the fins are distributed over said external surface of the plunging section; - in the transition zone, the crest height of the fins gradually increases until it joins the fins of the finned section; - the invention included any form of fin design regardless of their number, shape, dimensions and material; - the invention consisting of a nozzle ensuring the intrinsic ventilation of a container is described herein from the perspective of fins "added" to the surface of the plunging section and also includes any design in the form of hollows formed by "material removal", such as grooves, in the outer surface of the plunging section.

[0020] Beyond these main and secondary features, and similarly to what is described in the prior art, the pipette tip of the present invention advantageously comprises, in its upper / proximal portion, a reservoir surmounted by a slightly enlarged area allowing the pipette tip to be inserted onto the manual, semi-automated, or automated sampling device. In another preferred embodiment of the present invention, the enlarged upper portion of the pipette tip advantageously includes a stop for positioning in storage racks. The interior of this upper section also advantageously includes a stop for reproducible axial positioning on automatic pipettes.

[0021] Finally, it should be noted that the closed system ventilation function attributed to the pipette tips according to the invention does not in any way prevent their use in open systems.

[0022] More formally, a first aspect of the invention relating to a pipette tip is described by the wording of claim 1 and a second aspect of the invention relating to a use of the above pipette tip is described by the wording of claim 7.

[0023] Preferred embodiments of the invention are described in the secondary claims.

[0024] The present invention maintains the principle of the state of the art by retaining a conical, continuous shape of cylindrical symmetry at the end of the nozzle to: allow a leak-proof interface with fluidic connection elements such as, for example, injection ports; - to preserve the beneficial effects of the thin-walled capillary tube, such as limiting the force exerted on the septa, a smaller droplet size, a centered droplet, or laminar flow when emptying the tip

[0025] According to the invention, the addition of axial fins on the plunging section of the pipette tip provides the following benefits: - ventilation of rigid or semi-rigid containers in a closed / septum-sealed system, regardless of their shape and nature; - effective ventilation throughout the fluid transfer process: after piercing, as soon as the fins come into contact with the septum; throughout the process of immersing the tip in the container, through the septum; during the sequence of dispensing the liquid solution and throughout the process of removing the tip from the container, through the septum at least until the fins exit the septum. Brief description of the figs

[0026] Figure 1 shows an elevation view and a cross-sectional view of a first embodiment of a pipette tip according to the prior art.

[0027] Figure 2 shows an elevation view and a cross-sectional view of a second embodiment of a pipette tip according to the prior art.

[0028] Figure 3 shows, in cross-section, the aspiration and injection of liquid into an open container using a pipette according to the prior art.

[0029] Figures 4 and 5 represent, respectively in perspective view and in section view, the aspiration and injection of liquid into a closed container, namely fitted with a stopper or any septum, using a pipette according to the prior art.

[0030] Figures 6 and 7 represent, respectively in an elevation (or front) view and in a perspective view, an embodiment of a pipette tip according to the present invention.

[0031] Figure 8 represents, in perspective view, the aspiration and injection of liquid into a closed container, namely fitted with any stopper or septum, using a pipette according to the present invention.

[0032] Figures 9A and 9B represent two non-limiting examples of fin embodiments according to the invention.

[0033] Figure 10 represents, in perspective view, an embodiment of a pipette tip according to the present invention, in which the fins are formed by grooves cut into the surface of the tip.

[0034] Figure 11 (including a detail view) represents, in cross-section, the aspiration and injection of liquid into a closed container, namely one equipped with any septum, using a pipette according to the present invention.

[0035] Figures 12A to 12C show cross-sectional views for interfacing the pipette tip according to the invention with different types of injection ports, respectively cone on cone, cone on O-ring and cone on shoulder. Detailed description of the invention

[0036] The present invention relates to a pipette tip designed to provide ventilation during liquid transfers into and from any container equipped with a septum.

[0037] Any container is a receptacle of any type, size, and shape, such as a flask, test tube, PCR plate well, optical cuvette, etc., fitted with a septum of any shape (stopper, liner, adhesive film, heat seal, etc.) and made of any material (elastic or elastomeric, natural or synthetic rubber, plastic, etc.). Flasks, closed by septa, or PCR plate wells or similar containers closed by adhesive or heat sealable films of various types. materials, are all non-limiting examples of any container equipped with a septum.

[0038] Figures 6 and 7 schematically illustrate a pipette tip 30 according to an embodiment of the present invention. The upper part 31 of the pipette tip, located just above the main reservoir 32, is slightly enlarged to allow the pipette tip to be inserted onto a manual, semi-automated, or automated fluid handling device, such as a pipette or a pipetting robot. A stop 36 allows the pipette tips to be positioned and held in position within the packaging racks.

[0039] Advantageously, the addition of axial fins 37 on the plunge section 33 and the transition zone 34 of the pipette tip provides a major innovative benefit: ventilation of containers in a closed system sealed by a septum, regardless of their shape and nature. Indeed, as shown in Figures 8 and 9, the interface 38 between the septum 26 and the finned pipette tip 30 is not airtight because the septum rests on the outside of the fins and does not deform sufficiently to hermetically seal the gaps between the fins, thus creating openings between the tip and the septum, ensuring ventilation at any stage of the pipetting process.

[0040] It should be noted that the invention covers all forms of vent design, two typical examples of which are shown in Figure 9: (A) either a vision in the form of fins "added to the surface": the width of the fins 37 is less than or equal to the distance between two fins 37; (B) or a vision in the form of grooves "carved into the surface": the width of the fins 37 is greater than the distance between two fins 37.

[0041] The function and effect of the two types of fins is similar: the septum cannot penetrate the hollows, which leaves an opening ensuring good ventilation of the container.

[0042] As shown in Figure 11, at any given time, equation 28 (P1 = P2) holds thanks to ventilation through the gaps between the mouthpiece and the septum. This ventilation is beneficial because it reduces, or even eliminates, the effects of pressurization and depressurization of the container during liquid withdrawal and injection operations, and during the immersion and removal of the nozzle in and out of the container, which: - limits, or even eliminates, the risk of overflow or leakage of liquid during the piercing of the septum and the immersion of the tip in the container; - guarantees precise sampling and volumetric dosing in the tip, using a manual, semi-automatic or automatic pipette (such as a pipetting robot); - limit, see eliminates the loss of liquid out of the tip when removing the tip from the container, through the septum.

[0043] Furthermore, according to a preferred embodiment of the present invention, the transition zone 34 between the finned section 33 and the end cone 35 is conical in shape to limit the force exerted during the transition from section 35 to section 33 when the nozzle is inserted through the septum. Limiting the length of the transition zone 34 between the finned section 33 and the end cone 35, and progressively reducing the height of the fins, ensures ventilation of the container for as long as possible during the withdrawal phase of the nozzle from the container through the septum.Furthermore, a difference in diameter / width between the finned section 33 and the tip of the nozzle 35 causes the wide section to deform the septum and generate a hole large enough in the septum so that the seal between the septum and the end of the tip cone is imperfect, which ensures slight ventilation even at the end of the movement of withdrawing the nozzle from the container, through the septum.

[0044] On the different types of interfacing between a conical and continuous pipette tip 35 according to the invention and injection ports 41, 42, 43 shown in the respective figures 12A to 12C, we note the importance of not having a fin 37 on the tip in order to guarantee a perfectly sealed interface. List of reference symbols 1 conventional pipette tip 2 body sections 3 upper section / crown 4 upper wall segment 5 locking chamber 6 lower wall segment 7 sealing chamber 8 open end 9 entrance section 10 cylindrical section 11 external circumferential ribs 12 lower end of rib 13 pipette tip 14 col 15 pipette tip bodies 16 peripheral plate 17. Pipette opening 18 support ribs 19 conventional pipette tip 20 container / receptacle 21 liquid 22 liquid sampled 23 pipette tip / container space 24 vertical pipette movement 25 directions of suction and drainage of the extracted liquid 26 septum 27 continuous circumferential contact 28 pressure differential 30 pipette tips according to an embodiment of the present invention 31 upper part of pipette tip 32 main tank plunge section, transition zone, tip end / tip stop, axial fin, interface between the septum and the pipette tip, tip orifice, injection port cone, injection port seal, injection port shoulder

Claims

AMENDED CLAIMS received by the International Bureau on 05 December 2025 (05.12.2025) 1. A pipette tip (30) for a manually, semi-automatically, or automatically operated pipette, intended to be inserted into a container (20) through a septum (26) for withdrawing and / or injecting a liquid (21), said pipette tip (30) having, on an external surface of a plunge section (33), one or more axial fins (37), said plunge section (33) being called the finned section, allowing ventilation of the container (20) during a fluid transfer / pipetting process, characterized in that said pipette tip (30) has a tip end section or point (35), of a continuous conical shape having a first cone angle, devoid of axial fins (37) and provided with an orifice (39) at the end of said cone, and in that said pipette tip (30) has a transition zone (34) between the section and fins (33) and the tip end section (35),said transition zone (34) being conical in shape having a second cone angle and comprising an extension for each of said fins (37) of the plunging section (33) contributing to said ventilation, the first cone angle being smaller than the second cone angle.

2. The pipette tip (30) according to claim 1, characterized in that the finned section (33) is located between a main reservoir (32) of the tip (30) and the tip end section or point (35).

3. The pipette tip (30) according to claim 1 or 2, characterized in that the fins (37) are distributed on said external surface of the plunging section (33).

4. The pipette tip (30) according to any one of claims 1 to 3, characterized in that, in the transition zone (34), the crest height of the fins (37) increases progressively from 0 until it reaches, at the same height as these, the fins (37) of the finned section (33).

5. The pipette tip (30) according to any one of the preceding claims, characterized in that, in order to ensure the aforementioned ventilation, either fins (37) are added to the surface of the tip (33), in which case the width of the fins (37) is less than or equal to the distance between two fins (37), either grooves are cut into the surface of the tip (33), in which case the width of the fins formed (37) is greater than the distance between two fins (37), or a combination of fins and grooves is provided, regardless of their number, shape, dimensions and arrangement.

6. The pipette tip (30) according to any one of the preceding claims, characterized in that it is configured for single, multiple or durable / reusable use.

7. Use of a pipette tip (30), according to any one of the preceding claims, on any fluid transfer device, such as syringe, pipette, etc., manually, semi-automatically or automatically operated, to transfer a liquid into and from any container equipped with a septum or closed container (20), ventilation of the closed container (20) being ensured at all times during the fluid transfer / pipetting process.

8. Use according to claim 7, for a leak-proof interface of the pipette tip (30) with a fluidic connection element such as an injection port (41, 42, 43).

9. Use according to claim 7, characterized in that the container (20) is of any type, size or shape.

10. Use according to claim 9, characterized in that the container (20) is a vial, a test tube, a PCR plate cuvette or an optical cuvette.

11. Use according to claim 7, characterized in that the septum (26) is of any shape, such as stopper, liner, adhesive film, heat sealable, etc., and of any material such as plastic, elastic or elastomeric material, natural or synthetic rubber, etc.

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