Pipette tip with outer sealing collar

Abstract

The pipette tip (10) comprises an elongated tubular body (12) having a head (14) for mounting the pipette tip (10) into a receptacle (52) of a pipetting device; wherein the tubular body (12) comprises an orifice (20) opposite the head (14), whereby the orifice (20) is connected with an opening (16) in the head (14) via the tubular body (12); wherein the head (14) comprises a sealing collar (24) surrounding the head (14); and wherein the sealing collar (24) is connected to the head (14) opposite the orifice (20) and extends along the head (14) in a direction to the orifice (20).

Description

Technical Field

[0001] This invention relates to a pipette tip, and more particularly to a pipette tip for use in laboratory automation equipment. Background Technology

[0002] Laboratory automation equipment is used to automate laboratory processes such as transferring liquids between samples, liquid containers, and wells, as well as analyzing liquids. Laboratory automation equipment typically includes a pipette arm for carrying and automatically moving one or more pipette tips. With the pipette head attached to the pipette arm, the pipette tip can be clamped before use and set after use. Some pipette tips are clamped by inserting a connecting piece into a collar of the pipette tip. The connecting piece may include one or more O-rings for an airtight seal between the inner wall of the collar and the connecting piece. Other pipette tips are clamped by inserting the upper end of the pipette tip into the receiving portion of the pipette head. The pipette tip includes a sealing device similar to a sealing lip.

[0003] To secure the pipette tip to the receiving portion, the pipette tip typically includes a sealing lip that surrounds the upper end of each pipette tip. When the pipette tip is inserted into the corresponding receiving portion, the sealing lip rotates or flips, resulting in considerable force, especially when using a head, such as one with 384 receiving portions, into which multiple pipette tips are inserted.

[0004] In addition, the injection molding process for the pipette tip is quite complex and time-consuming because a multi-part form with additional workpieces for each lip must be used.

[0005] US 6 955 077 B2 and US 2003 0 219 359 A1 describe pipette tips having a sealing lip inside the pipette tip. Summary of the Invention

[0006] The purpose of this invention is to simplify the formation of the pipette tip, reduce the force required to insert the pipette tip into the receiving portion of the pipette arm, and increase the accuracy of the alignment between the pipette tip and the receiving portion.

[0007] This objective is achieved through the subject matter of the independent claims. Further exemplary embodiments will be apparent from the dependent claims and the following description.

[0008] This invention relates to a pipette tip. Typically, a pipette tip is a device for transferring liquids, attached to a pipette head mounted on the arm of a laboratory automation device. The pipette tip has a hollow body for receiving liquid and an orifice at one end for drawing and dispensing liquid. At the other end, the laboratory automation device generates a pressure different from the ambient pressure within the pipette tip, thereby causing the liquid to be drawn or dispensed. The pipette tip can be a disposable pipette tip, which can be automatically attached to and detached from the laboratory automation device.

[0009] According to one embodiment, the pipette tip includes an elongated tubular body with a head for mounting the pipette tip into a receiving portion of a pipetting device, wherein the tubular body includes an orifice opposite to the head, the orifice being connected via the tubular body to an opening in the head. Typically, the pipette can be made of a plastic material (such as polypropylene). Furthermore, the pipette tip may be approximately rotationally symmetrical about a central axis. At the end to be connected to a laboratory automation device, the tubular body has an opening, the opening being connected to the orifice via an internal space of the tubular body. The internal space of the tubular body consists of cylindrical and / or conical segments.

[0010] It must be understood that, here and below, the term "cylindrical" also refers to a conical surface that has an angle of less than 3° relative to its central axis.

[0011] According to one embodiment, the head includes a sealing collar surrounding the head, wherein the sealing collar is connected to the head on a side opposite to the orifice (i.e., on the side of the opening) and extends along the head in a direction leading to the orifice. The sealing collar may have a thickness such that it is flexible and can bend toward the central axis when the head is inserted into the receiving portion of the laboratory automation device. The sealing collar slides within the receiving portion and is secured against the inner wall of the receiving portion.

[0012] Because the sealing collar extends along the head, i.e., substantially parallel to the surface of the head and / or the central axis of the pipette tip, it can have a larger area suitable for sealing compared to a sealing lip that projects orthogonally from the head. In this way, a single sealing collar may be sufficient to secure the pipette tip to the receiving portion of the laboratory automation device.

[0013] Additionally, the head between the sealing collar and the opening facing the laboratory automation equipment may have a surface that fits into the receiving portion without requiring deformable parts, such as a sealing lip. This can improve the guidance and / or alignment of the head within the receiving portion.

[0014] Furthermore, the pipette tip can be injection molded using a mold consisting of only two parts that are closed to each other in the axial direction. One part forms the head, and the other part forms the remainder of the pipette tip, including the orifice and the collar. Standard injection molding tools can be used. This simplifies and increases the manufacturing speed of the pipette tip.

[0015] According to one embodiment, the sealing collar includes a tubular sealing member that surrounds the head at a distance. The tubular seal provides an outer surface designed to seal and / or secure to the inner surface of the receiving portion, into which the head is inserted. The sealing member can be connected to the head via a ring having a decreasing outer and inner radius relative to the central axis. As the head is inserted and / or moved into the receiving portion, the ring and a portion of the tubular sealing member slide within the receiving portion, and the portion of the tubular sealing member deforms toward the central axis. The tubular sealing member then presses against the inner surface of the receiving portion, thereby providing a seal.

[0016] According to one embodiment, the tubular sealing member surrounds the head at least partially along a section extending in the axial direction at a constant distance. The tubular sealing member may have a cylindrical inner surface and a cylindrical outer surface. In this way, the distance between the opening in the head and the area where the tubular sealing member presses against the inner surface of the receiving portion can vary within a specific interval defined by the length of the tubular sealing member.

[0017] On the one hand, this could be beneficial for mitigating manufacturing inaccuracies. On the other hand, the pipette tip of the laboratory automation device having multiple receptacles can be designed such that the boundaries of the different receptacles pressing against the tubular seal are aligned at different heights. When such a tip is lowered onto multiple pipette tips for mounting, the force used to press the pipette tip against the pipette tip can be reduced. The length of the tubular seal defines the maximum possible distance between these boundaries.

[0018] According to one embodiment, the tubular sealing member has a constant thickness at least partially along a section extending in the axial direction. The thickness of the tubular sealing member can be thinner than (e.g., at least 50% thinner) the thickness of the material of the head beneath the tubular sealing member. In this way, the tubular sealing member can be flexible, while the head can be substantially rigid. The sealing collar can also have a varying thickness.

[0019] According to one embodiment, the length of the tubular sealing member in the axial direction of the pipette tip is at least three times or at least five times the distance between the tubular sealing member and the head. As described above, the length of the tubular sealing member defines an area in which the sealing collar can provide a seal to the interior of the receiving portion.

[0020] According to one embodiment, the outer diameter (or radius relative to the central axis) of the head below the tubular sealing member is smaller than the outer diameter (or radius) of the head between the opening in the sealing collar and the head. Since the cavity between the tubular sealing member and the head may require a specific thickness, this allows for a reduction in the difference between the outer diameter (or radius) of the tubular sealing member and the outer diameter (or radius) of the head between the opening in the sealing collar and the head.

[0021] According to one embodiment, the sealing collar includes a tubular positioning member that surrounds the head at a distance and includes an outer edge projecting radially and facing an opening in the head. The tubular positioning member may be connected to a tubular sealing member of the sealing collar on the side facing the opening. With respect to this embodiment, the sealing collar may include a ring with an increased outer diameter (or radius) connected to the head, a tubular sealing member connected to the ring and having a substantially constant outer diameter, and a tubular positioning member having an outer diameter (or radius) larger than that of the tubular sealing member. The outer edge may have a surface substantially orthogonal to the central axis, the surface starting at the outer diameter (or radius) of the tubular sealing member and ending at the outer diameter (or radius) of the positioning member.

[0022] When the tip of the pipette is moved into the receiving portion of the laboratory automation device, the movement can be stopped by the edge, which then contacts the boundary of the receiving portion.

[0023] According to one embodiment, the tubular positioning member includes another outer edge projecting radially and facing the orifice. This other outer edge may be arranged opposite to the outer edge facing the opening. The other outer edge may have a surface substantially orthogonal to the central axis, the surface beginning at the outer diameter (or radius) of the tubular sealing member and ending at the outer diameter (or radius) of the positioning member. When the pipette tip is stacked in a tray including an orifice for receiving the pipette tip, this other edge prevents the pipette from falling through the tray.

[0024] According to one embodiment, the outer radius of the tubular positioning member is greater than the outer radius of the tubular sealing member and / or the inner radius of the tubular positioning member is greater than the inner radius of the tubular sealing member. The thickness of the tubular positioning member may be approximately the same as the thickness of the tubular sealing member.

[0025] According to one embodiment, below the tubular sealing member and the tubular positioning member, the head has a cylindrical outer surface (or a constant outer radius relative to the central axis). The cavity below the sealing collar may have its maximum thickness at the end of the tubular positioning member, the thickness of which may then decrease and shrink to zero below the tubular sealing member, wherein the sealing collar is connected to the head. The surface of the cavity provided by the outer side of the head may be cylindrical. Such a cavity can be readily formed using injection molding.

[0026] According to one embodiment, the head has axially aligned fins that project radially from a cylindrical member of the head. A sealing collar can be attached to and surround the cylindrical member. The fins reduce the material thickness in the section of the pipette. The outer surface of the fins provides guidance for inserting the pipette tip into the receiving portion of the laboratory automation device.

[0027] According to one embodiment, the outer diameter of the fin is smaller than the outer diameter of the sealing collar. This allows the boundary of the receiving portion to press the sealing collar inward.

[0028] According to one embodiment, the outer diameter of the cylindrical member of the head is equal to the outer diameter of the head below the sealing collar. The substantially constant thickness of the wall of the pipette tip can be advantageous for injection molding.

[0029] According to one embodiment, the outer surface of the fins merges into the outer surface of the sealing collar. This helps guide the boundary of the receiving portion above the sealing collar.

[0030] According to one embodiment, at the opening in the head, the outer surface of the head is tapered (i.e., has a conical surface), such that the outer diameter of the head decreases towards the opening. This can help to center the tip of the pipette within the receiving portion.

[0031] According to one embodiment, at the opening in the head, the inner surface of the head is tapered, such that the inner diameter of the head increases toward the opening. This can facilitate placing the filter within the tip of the pipette.

[0032] According to one embodiment, in the section between the opening and the end of the sealing collar facing the orifice, the inner surface of the head is cylindrical. As already mentioned, in this section, a filter can be placed into the tip of the pipette. After the cylindrical section, the inner surface may become conical facing the orifice.

[0033] These and other aspects of the invention will become apparent from the embodiments described below and will be elucidated with reference to the embodiments described below. Attached Figure Description

[0034] Embodiments of the present invention will now be described in more detail with reference to the accompanying drawings.

[0035] Figure 1 A pipette tip according to an embodiment of the present invention is shown.

[0036] Figure 2a The tip of a pipette tip according to an embodiment of the present invention is shown.

[0037] Figure 2b It shows Figure 2a A cross-sectional view of the head.

[0038] Figure 3a The tip of a pipette tip according to another embodiment of the present invention is shown.

[0039] Figure 3b It shows Figure 3a A cross-sectional view of the head.

[0040] Figure 4 It shows Figures 2a to 3b A cross-sectional view of a portion of the head.

[0041] Figure 5 A cross-sectional view of the head of several pipette tips inserted into a receiving portion of a laboratory automation device according to an embodiment of the present invention is shown.

[0042] The reference numerals used in the accompanying drawings and their meanings are listed in summary form in the reference numeral list. In principle, the same parts have the same reference numerals in the accompanying drawings. Detailed Implementation

[0043] Figure 1 A pipette tip 10 with an elongated tubular body 12 is shown. The elongated tubular body 12 has a head 14 for mounting the pipette tip 10 into the receiving portion of a pipetting device. The pipette tip 10 is made of a plastic material (such as polypropylene) by injection molding. The pipette tip 10 and the elongated tubular body 12 are approximately rotationally symmetrical with respect to the central axis of the pipette tip 10.

[0044] The elongated tubular body 12 has an opening 16 on one side of its head 14, which leads to a tubular cavity 18 within the elongated tubular body 12. At the opposite end to the head, the tubular cavity terminates in an orifice 20. The orifice 20 is connected via the tubular body 12 to the opening 16 in the head 14. By applying a pressure below ambient pressure to the opening 16, the pipette 10 is inserted into a laboratory automation device with its head 14, which is capable of drawing liquid into the pipette tip 10, i.e., into the tubular cavity 18, and dispensing liquid from the pipette tip 10 (i.e., from the tubular cavity 18) by applying a pressure above ambient pressure.

[0045] The head 14 has a generally cylindrical shape, while the section of the elongated tubular body 12 with the orifice 20 is generally conical. Only the fins 22 extending parallel to axis A on the outer side of the head 14 may disrupt rotational symmetry.

[0046] The head 14 also includes a sealing collar 24 surrounding the head 14.

[0047] The sealing collar 24 is connected to the head 14 on the side opposite to the orifice by a ring 26 and extends along the head 14 in the direction leading to the orifice 20.

[0048] Figure 2a and Figure 2b An embodiment of the upper portion of a pipette tip 10 is shown, the pipette tip 10 having a head 14 with a cylindrical outer surface. Figure 3a and Figure 3b An embodiment of the upper portion of a pipette tip 10 is shown, the pipette tip 10 having a head 14 with fins 22.

[0049] In both embodiments, at the opening 16, the outer surface 28 of the head 14 is tapered, i.e., conical, such that the outer diameter of the head 14 decreases toward the opening 16. This facilitates insertion of the head 14 into the receiving portion of laboratory automation equipment. Furthermore, at the opening 16, the inner surface 30 of the head 14 is tapered, such that the inner diameter of the head 14 increases toward the opening 16. This facilitates insertion of the filter into the tubular cavity 18 within the head 14.

[0050] In the section of the pipette tip 10 between the opening 16 and the end of the sealing collar 24 facing the orifice 20, the inner surface 32 of the head 14 is cylindrical. In the section of the pipette tip 10 behind the end of the sealing collar 24 facing the orifice 20, the inner surface 34 of the tubular cavity 18 is conical.

[0051] exist Figure 2a and Figure 2b In one embodiment, the head 14 has a cylindrical outer surface 36 for guiding the head 14 into the receiving portion of the laboratory automation equipment.

[0052] exist Figure 3a and Figure 3b In one embodiment, the head 14 has axially aligned fins 22 that project radially from a cylindrical member 38 of the head 14. Inwardly, the cylindrical member 38 is defined by an inner surface 32. The outer surface of this cylindrical member is the surface of the head 14 other than the fins 22. The outer diameter of the cylindrical member 38 can be equal to the outer diameter of the head 14 below the sealing collar 24. In this way, a substantially uniform wall thickness can be achieved.

[0053] The outer surface of fin 22 is used to guide head 14 into the receiving part of laboratory automation equipment. The outer diameter of fin 22 is smaller than the outer diameter of sealing collar 24.

[0054] The outer surface of fin 22 merges into the outer surface of sealing ring 24, and specifically merges into the outer surface of ring 26. Regarding Figure 2a and Figure 2b This also applies to the outer surface 36 of the head 14.

[0055] Figure 4The portion of the pipette tip 10 with the sealing collar 24 is shown in more detail. It can be seen that the sealing collar 24 is connected to the head 14 via a ring 26, the diameter of which increases relative to axis A. The ring 26 becomes a tubular sealing member 40 of the sealing collar 24, which surrounds the head 14 at a distance. That is, the tubular sealing member 40 is not directly connected to the head 14. The tubular sealing member 40 surrounds the head 14 at least partially along a section extending in the axial direction A at a constant distance. The tubular sealing member 40 has a constant thickness at least partially along the section extending in the axial direction A.

[0056] The tubular sealing member 40 extends toward the orifice 20. When the head 14 is inserted into the receiving portion of the laboratory automation equipment, the tubular sealing member 40 is pressed against axis A and provides a sealing surface relative to the inner surface of the receiving portion. Because the tubular sealing member 40 extends in the axial direction, this sealing surface can be significantly larger than the seal provided by the sealing lip that protrudes in the radial direction.

[0057] The length of the tubular sealing member 40 in the axial direction A of the pipette tip is much longer than its distance from the head 14. For example, this length is at least three times the distance between the tubular sealing member 40 and the head 14. In this way, a large sealing area can be achieved by the outer side of the tubular sealing member 40.

[0058] from Figure 4 as well as Figure 2a and 2b As can be seen, the outer diameter of the head 14 below the tubular sealing member 40 can be smaller than the outer diameter of the head 14 between the sealing collar 24 and the opening 16 in the head 14. It is also possible that the outer diameter of the head 14 below the tubular sealing member 40 is smaller than the outer diameter of the fin 22, such as... Figure 3a and Figure 3b As shown. In this way, the difference between the outer diameter of the guide surface of the head 14 and the sealing surface of the tubular sealing member 40 can be reduced, which can help insert the head 14 into the receiving part of the laboratory automation equipment.

[0059] The sealing collar also includes a tubular positioning member 42 that surrounds the head 14 at a distance. Specifically, the tubular positioning member 42 is connected to the tubular sealing member 40 of the sealing collar 24. When moved in the direction of the orifice 20, the tubular sealing member 40 rotates into the tubular positioning member 42.

[0060] The tubular positioning member 42 includes an outer edge 44 that projects radially and faces the opening 16 in the head 14. The edge 44 provides a stop for moving the head 14 into the receiving portion of the laboratory automation equipment.

[0061] The tubular positioning member 42 includes another outer edge 46 that projects radially and faces the orifice 20. This edge 46 provides a stop for the pipette tip 10 when it is stored on the tray.

[0062] The outer and inner radii of the tubular positioning member 42 are both larger than those of the tubular sealing member 40. The tubular positioning member 42 has approximately the same thickness as the tubular sealing member 40.

[0063] Below the ring 26, the tubular sealing member 40, and the tubular positioning member 42, the head 14 has a cylindrical outer surface 48. An increased-width cavity is formed by utilizing the inner surface of the ring 26, the tubular sealing member 40, and the tubular positioning member 42, whose radius and / or diameter increases in the direction toward the orifice 20. This cavity can be easily created during injection molding. The width of this cavity below the tubular sealing member 40 can be approximately the thickness of the tubular sealing member 40. The width of this cavity below the tubular positioning member 42 can be approximately twice or more the width of the cavity below the tubular sealing member 40.

[0064] Figure 5 A cross-sectional view of a portion of a pipette head 50 of a laboratory automation device is shown. The pipette head 50 has one or more receptacles 52 for receiving the head 14 of a pipette tip 10. Each receptacle 52 has an inner wall 54 having a diameter approximately the same as the outer diameter of the head 14. All receptacles 52 terminate in a plane P defined by the lower end of the pipette head 50. At a specific distance from this plane P, each receptacle 52 has an edge 56, wherein the inner diameter of the receptacle 52 decreases to the diameter of the inner wall 54. At this edge 56, a sealing collar 24, particularly a tubular sealing member 40, is pressed against the axis A, forming a sealing region 58 between the inner wall 54 and the sealing collar 24.

[0065] like Figure 5 As shown, the distance of the edge 56 from the plane P can be varied, thus reducing the total force when multiple pipette tips 10 are inserted into the receiving portion 52. This distance can vary within the length of the tubular sealing member 40.

[0066] Although the invention has been detailed and described in the accompanying drawings and the foregoing description, such description is to be considered illustrative or exemplary rather than restrictive; the invention is not limited to the disclosed embodiments. Other variations of the disclosed embodiments can be understood and implemented by those skilled in the art and those who practice the claimed invention upon studying the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite articles "a" or "an" do not exclude multiple. A single processor or controller or other unit can perform the functions of several items recited in the claims. The fact that certain measures are recited in mutually different dependent claims does not mean that a combination of these measures cannot be used advantageously. Any reference numerals in the claims should not be construed as limiting the scope.

[0067] Reference Symbol List

[0068] 10: Pipette tip

[0069] 12: Tubular body

[0070] 14: Head

[0071] 16: Opening

[0072] 18: Tubular cavity

[0073] 20: Orifice

[0074] 22: Fins

[0075] 24: Sealing ring

[0076] 26: Ring

[0077] A: Axis

[0078] 28: Outer surface

[0079] 30: Inner surface

[0080] 32: Inner surface

[0081] 34: Inner surface

[0082] 36: Outer surface

[0083] 38: Cylindrical components

[0084] 40: Tubular sealing component

[0085] 42: Tubular positioning component

[0086] 44: Outer edge

[0087] 46: The other edge

[0088] 48: Outer surface

[0089] 50: Pipette tip

[0090] 52: Reception Section

[0091] 54: Inner wall

[0092] 56: Edge

[0093] 58: Sealed area

[0094] P: Plane

Claims

1. A pipette tip (10), in, The pipette tip (10) includes an elongated tubular body (12) having a head (14) for mounting the pipette tip (10) into the receiving portion (52) of the pipetting device; The tubular body (12) includes an opening (20) opposite to the head (14), and the opening (20) is connected to the opening (16) in the head (14) via the tubular body (12); The head (14) includes a sealing collar (24) surrounding the head (14); The sealing collar (24) is connected to the head (14) opposite to the orifice (20) and extends along the head (14) in the direction leading to the orifice (20).

2. The pipette tip (10) according to claim 1, in, The sealing collar (24) includes a tubular sealing member (40) that surrounds the head (14) at a distance.

3. The pipette tip (10) according to claim 2, in, The tubular sealing member (40) surrounds the head (14) at least partially along a section extending in the axial direction (A) at a constant distance.

4. The pipette tip (10) according to claim 2 or 3, in, The tubular sealing member (40) has a constant thickness at least partially along a section extending in the axial direction (A).

5. The pipette tip (10) according to any one of claims 2 to 4, in, The length of the tubular sealing member (40) in the axial direction (A) of the tip of the pipette is at least three times the distance between the tubular sealing member (40) and the head (14).

6. The pipette tip (10) according to any one of claims 2 to 5, in, The outer diameter of the head (14) below the tubular sealing member (40) is smaller than the outer diameter of the head (14) between the sealing collar (24) and the opening (16) in the head (14).

7. The pipette tip (10) according to any one of the preceding claims, in, The sealing collar (24) includes a tubular positioning member (42) that surrounds the head (14) at a distance and includes an outer edge (44) that protrudes in the radial direction and faces the opening (16) in the head (14).

8. The pipette tip (10) according to claim 7, in, The tubular positioning member (42) includes another outer edge (46) that protrudes in the radial direction and faces the orifice (20).

9. The pipette tip (10) according to claim 7 or 8, in, The tubular positioning member (42) is connected to the tubular sealing member (40) of the sealing collar (24).

10. The pipette tip (10) according to claim 9, in, The outer radius of the tubular positioning member (42) is greater than the outer radius of the tubular sealing member (40); The inner radius of the tubular positioning member (42) is greater than the inner radius of the tubular sealing member (40).

11. The pipette tip (10) according to claim 9 or 10, in, Below the tubular sealing member (40) and the tubular positioning member (42), the head (14) has a cylindrical outer surface (48).

12. The pipette tip (10) according to any one of the preceding claims, in, The head (14) has axially aligned fins (22) that protrude radially from the cylindrical member (38) of the head (14); Wherein, the outer diameter of the fin (22) is smaller than the outer diameter of the sealing collar (24); The outer diameter of the cylindrical component (38) is equal to the outer diameter of the head (14) below the sealing ring (24).

13. The pipette tip (10) according to claim 12, in, The outer surface of the fin (22) merges into the outer surface of the sealing collar (24).

14. The pipette tip (10) according to any one of the preceding claims, in, At the opening (16), the outer surface (28) of the head (14) is tapered, such that the outer diameter of the head (14) decreases toward the opening (16); At the opening (16), the inner surface (30) of the head is tapered, such that the inner diameter of the head (14) increases toward the opening (16).

15. The pipette tip (10) according to any one of the preceding claims, in, In the section between the opening (16) and the end of the sealing collar (24) facing the orifice (20), the inner surface (32) of the head (14) is cylindrical.

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