Attachment for pipette

Abstract

To provide an attachment for a pipette capable of reducing a burden on a user even when using an existing pipette.SOLUTION: The attachment 14 for micropipettes includes a first flow path 34 defined in the first member 32 and connected to the reservoirs, a second flow path 35 defined in the first member 32 and connected to the discharge nozzles, a third flow path 41 defined in the second member 33, extending from the micropipettes, and branching into a first branch path 41a connected to the first flow path 34 and a second branch path 41b connected to the second flow path 35, a first check valve formed of the rubber sheet 31 and allowing inflow of fluid from the first flow path 34 to the first branch path 41a, and a second check valve formed of the rubber sheet 31 and allowing outflow of fluid from the second branch path 41b to the second flow path 35.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an attachment for a pipette. [Background technology]

[0002] Pipettes are used as instruments for aspirating and transferring a predetermined volume of liquid from a source liquid. When using a pipette, the pipette must be refilled with new liquid every time a predetermined volume of liquid is dispensed from the pipette. This requires repeated reciprocal movement of the liquid from a reservoir to each destination. Patent Document 1 discloses a dispensing device that dispenses a predetermined volume of liquid according to the movement of a piston as a pipette. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 60-189834 Summary of the Invention [Problem to be solved by the invention]

[0004] In the dispensing device shown in Patent Document 1, new liquid is replenished from a reservoir via a tube into a dispensing container in response to the movement of a piston. The dispensing device eliminates the need to move the discharge nozzle back and forth between the reservoir and each individual dispensing destination each time a predetermined volume of liquid is dispensed, thereby reducing the burden on the user. However, because the dispensing device is assembled using parts with complex shapes, there is a problem in that it cannot be attached to existing pipettes, such as micropipettes, for use.

[0005] An object of the present invention is to provide an attachment for a pipette that can reduce the burden on the user even when using an existing pipette. [Means for solving the problem]

[0006] A pipette attachment according to one aspect of the present invention comprises a first member and a second member sandwiching a rubber sheet; a first flow path defined by the first member and connected to a reservoir; a second flow path defined by the first member and separated from the first flow path and connected to a discharge nozzle; a pipette connection path formed in the first member and / or the second member and connected to a pipette; a first branch path defined by the second member and connected to the pipette connection path and the first flow path; and a second branch path defined by the second member and connected to the pipette connection path and the second flow path. The rubber sheet forms a first check valve disposed between the first flow path and the first branch path to allow fluid to flow from the first flow path to the first branch path, and a second check valve disposed between the second flow path and the second branch path to allow fluid to flow from the second branch path to the second flow path. [Effects of the Invention]

[0007] According to the disclosed embodiment as described above, it is possible to connect to an existing pipette and avoid the need to move back and forth between the reservoir and each distribution destination, thereby reducing the burden on the user when using an existing pipette. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram illustrating the configuration of a micropipette system according to a first embodiment of the present invention. [Figure 2] FIG. 2 is an exploded perspective view of the pipette attachment. [Figure 3] FIG. 4 is a diagram schematically illustrating the configuration of a first check valve when the valve is closed. [Figure 4] FIG. 4 is a diagram schematically illustrating the configuration of a first check valve when it is open. [Figure 5] FIG. 4 is a diagram schematically illustrating the configuration of a second check valve when the valve is closed. [Figure 6] FIG. 4 is a diagram schematically illustrating the configuration of a second check valve when it is open. [Figure 7]FIG. 10 is a conceptual diagram showing how the first branch channel of the third flow channel is filled with fluid after the start of a pushing operation of the micropipette. [Figure 8] FIG. 10 is a conceptual diagram showing the state of fluid flowing into the second branch channel when the first branch channel is initially filled with fluid. [Figure 9] FIG. 10 is a conceptual diagram showing how a fixed volume of fluid flows into a third flow path. [Figure 10] FIG. 10 is a schematic diagram illustrating the configuration of a micropipette system according to a second embodiment of the present invention. [Figure 11] FIG. 10 is a schematic diagram illustrating the configuration of a micropipette system according to a third embodiment of the present invention. [Figure 12] 10 is a diagram showing the configuration when the first check valve is in an open state and the second check valve is in a closed state. FIG. [Figure 13] 10 is a diagram showing the configuration when the first check valve is in a closed state and the second check valve is in an open state. FIG. [Figure 14] FIG. 10 is a schematic diagram illustrating the configuration of a micropipette system according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0010] FIG. 1 shows a schematic diagram of a micropipette system 11 according to a first embodiment of the present invention. The micropipette system 11 includes a micropipette 12 and a pipette attachment (hereinafter simply referred to as the attachment) 14 that is attached to a pipette tip 13 of the micropipette 12. A reservoir 15 is connected to the attachment 14. The reservoir 15 holds a fluid 16 to be dispensed (e.g., a reagent liquid or a specimen liquid). A tube 17 extending from the reservoir 15 to the attachment 14 guides the fluid 16 from the reservoir 15 to the attachment 14. A volume of the fluid 16 is supplied to the attachment 14 according to the operation of the micropipette 12.

[0011] A discharge nozzle 18 is attached to the attachment 14 as an extension of the pipette tip 13. The discharge nozzle 18 extends linearly along an axial direction 27 of the pipette tip 13. The axial direction 27 is the axial direction of the pipette tip 13, the tip holder 23, and the ejector 26. A volume of fluid 16 determined by the operation of the micropipette 12 is discharged from the tip of the discharge nozzle 18. The attachment 14 is miniaturized to a size that, when attached to the tip of the pipette tip 13, allows the user of the micropipette 12 to see the tip of the discharge nozzle 18 when discharging the fluid 16. In this embodiment, the pipette tip 13 and discharge nozzle 18 of the micropipette 12 are preferably arranged linearly. In this case, the user can operate the micropipette 12 with the same ease of use as a general (existing) micropipette. Note that, since it is sufficient for the user to be able to operate the micropipette in the same manner as an existing micropipette, "arranged in a line" means that the axes of the pipette tip 13 of the micropipette 12 and the discharge nozzle 18 are aligned in a line, and also includes cases where the axes are misaligned to a certain degree. The discharge nozzle 18 is preferably made of, for example, a transparent material. Examples of materials that can be used for the discharge nozzle 18 include COP resin and PDMS resin. When the discharge nozzle 18 is made of a transparent material, the user can observe the movement of the fluid 16 inside the discharge nozzle 18.

[0012] The micropipette 12 includes a grip 21 and a push button 22 supported by the grip 21 so as to be displaceable in the axial direction. The push button 22 displaces from a reference position Sd at the top to a first stop Fs and a second stop Ss at the bottom. To use the micropipette 12, a user holds the grip 21. The push button 22 is pressed down with the thumb. When the push button 22 reaches the first stop Fs, the user feels a click in the thumb. When the push button 22 is further pressed down from the first stop Fs, it reaches the second stop Ss. The second stop Ss restricts the displacement of the push button 22. When the push button 22 is released from the driving force of the thumb, it returns to the reference position Sd.

[0013] A tip holder 23 is attached to the grip 21. A pipette tip 13 is connected to the tip of the tip holder 23. A variable volume chamber is defined within the tip holder 23, and its capacity (volume) changes according to the displacement of the push button 22. The change in capacity is achieved by the action of a piston that moves in conjunction with the push button 22. A spring is connected to the piston. The elastic force of the spring holds the push button 22 at the reference position Sd. When the push button 22 is driven to the reference position Sd, the variable volume chamber expands to its maximum.

[0014] The pipette tip 13 is connected to the variable volume chamber and defines a discharge path that opens at the tip opening. When the volume of the variable volume chamber decreases, the fluid 16 in the discharge path is pushed out and discharged from the tip opening of the pipette tip 13. When the volume of the variable volume chamber increases, the fluid 16 is sucked into the discharge path from the tip opening of the pipette tip 13.

[0015] An ejector 26 is attached to the tip holder 23. The ejector 26 is displaced in the axial direction 27 while being guided by the tip holder 23. In the reference position, the ejector 26 is held at a position away from the pipette tip 13 attached to the tip holder 23. When the ejector button 28 is pressed down, the ejector 26 descends. The driving force pressing down the ejector button 28 is transmitted directly to the ejector 26. The driving force of the ejector 26 causes the pipette tip 13 attached to the tip holder 23 to be displaced. In this way, the pipette tip 13 can be removed from the tip holder 23. A spring is connected to the ejector 26. The elastic force of the spring holds the ejector 26 in the reference position.

[0016] FIG. 2 is an exploded perspective view of the attachment 14. In FIG. 2, the axial direction of the pipette tip 13 (discharge nozzle 18) is indicated by the z-axis, the thickness direction of the attachment 14 perpendicular to the z-axis is indicated by the y-axis, and the width direction of the attachment 14 perpendicular to the y-axis and z-axis is indicated by the x-axis. As shown in FIG. 2, the attachment 14 includes a first member 32 and a second member 33 that sandwich a rubber sheet 31. The first member 32 defines a first flow path 34 connected to the reservoir 15 and a second flow path 35 connected to the discharge nozzle 18. The second flow path 35 is separated from the first flow path 34. The longitudinal direction of the first flow path 34 extends along the x-axis, and the longitudinal direction of the second flow path 35 extends in a direction different from the longitudinal direction of the first flow path 34 (in this embodiment, toward the z-axis). The first member 32 is preferably formed of, for example, a transparent material. The first member 32 is made of a material such as COP resin or PDMS resin. The first member 32 is made of a transparent material, so that the user can observe the movement of the fluid 16 inside the first member 32.

[0017] The first flow path 34 is established based on a groove formed on the surface 32a of the first member 32 and closed by the rubber sheet 31. The width of the groove is set to, for example, about 0.5 mm to 2.0 mm. The depth of the groove is set to, for example, about 0.1 μm to 1.0 mm. The second flow path 35 is established based on a groove formed on the surface 32a of the first member 32 and closed by the rubber sheet 31. The width of the groove is set to, for example, about 0.5 mm to 2.0 mm. The depth of the groove is set to, for example, about 0.1 μm to 1.0 mm. The rubber sheet 31 is overlaid on the surface 32a of the first member 32. The surface direction of the rubber sheet 31 is aligned along the xz plane (a plane including the x-axis and z-axis), and the surface direction is aligned along an extension of the axial direction (z-axis direction) of the pipette tip 13 connected to the tip holder 23 of the micropipette 12. The rubber sheet 31 is made of, for example, silicone resin, and the thickness of the rubber sheet 31 is preferably set to, for example, about 12 μm to 50 μm.

[0018] The first flow path 34 is provided with a port 36 that receives the tip of the tube 17 (Fig. 1). The tube 17 is fixed to the port 36, which is a suction port that receives the fluid 16 inside the attachment 14. The tube 17 is airtightly adhered to the port 36. The second flow path 35 is provided with a port 37 that receives the base of the discharge nozzle 18 (Fig. 1). The discharge nozzle 18 is fixed to the port 37, which is a discharge port that discharges the fluid 16 from inside the attachment 14. The discharge nozzle 18 is airtightly adhered to the port 37.

[0019] The second member 33 defines a third flow path 41, which is composed of a pipette connecting path 41c, a first branched path 41a, and a second branched path 41b. In this embodiment, the second member 33 defines the third flow path 41, which extends from the pipette connecting path 41c and branches into a first branched path 41a connected to the first flow path 34 and a second branched path 41b connected to the second flow path 35. The pipette connecting path 41c is connected to the micropipette 12. The first branched path 41a is connected to the pipette connecting path 41c and the first flow path 34. The second branched path 41b is connected to the pipette connecting path 41c and the second flow path 35. The third flow path 41 is established based on a groove formed on the surface 33a of the second member 33 and closed by the rubber sheet 31. The width of the groove is set to, for example, approximately 0.5 mm to 2.0 mm. The depth of the groove is set to, for example, approximately 0.1 μm to 1.0 mm. The rubber sheet 31 is placed on the surface 33a of the second member 33. A port 42 that receives the tip of the pipette tip 13 is provided in the pipette connection path 41c. The pipette tip 13 is, for example, detachably inserted into the port 42. The second member 33 is preferably made of, for example, a transparent material. Examples of materials that can be used for the second member 33 include COP resin and PDMS resin. Because the second member 33 is made of a transparent material, the user can observe the movement of the fluid 16 inside the second member 33.

[0020] As shown in FIG. 3 , a first check valve 43 is disposed between the first flow path 34 and the first branch path 41a. The first check valve 43 is formed based on a single cut 44 cut into the rubber sheet 31. The first flow path 34 and the first branch path 41a overlap at an overlapping region 45, with the rubber sheet 31 in between. The first check valve 43 is formed by positioning the cut 44 in the rubber sheet 31 outside the overlapping region 45 and within a region of the first branch path 41a that does not overlap with the first flow path 34. When positive pressure is generated in the first branch path 41a, the rubber sheet 31 of the first check valve 43 comes into close contact with the first member 32 between the overlapping region 45 and the cut 44. By coming into close contact with the first member 32, deformation of the rubber sheet 31 is restricted, and the cut 44 enters a closed state. The first check valve 43 can prevent the fluid 16 from flowing out from the first branch path 41a to the first flow path 34 when the cut 44 of the rubber sheet 31 is in a valve-closed state.

[0021] As shown in FIG. 4 , when negative pressure is generated in the first branch path 41a, the rubber sheet 31 of the first check valve 43 moves away from the first member 32 between the overlap region 45 and the notch 44. A gap is thus formed between the rubber sheet 31 and the first member 32. The gap opens to the first branch path 41a through the notch 44. The notch 44 of the rubber sheet 31 of the first check valve 43 is in an open state. In this embodiment, the rubber sheet 31 around the notch 44 moves away from the xz plane, forming a gap between the rubber sheet 31 and the first member 32 and thus opening the first check valve 43. When open, the first check valve 43 allows the fluid 16 to flow from the first flow path 34 to the first branch path 41a. The unidirectionality of the first check valve 43 is ensured by the distance D1 between the overlap region 45 and the notch 44.

[0022] As shown in FIG. 5 , a second check valve 47 is disposed between the second flow path 35 and the second branch path 41b. The second check valve 47 is formed based on a single cut 48 cut into the rubber sheet 31. The second flow path 35 and the second branch path 41b overlap at an overlapping region 49, with the rubber sheet 31 in between. The second check valve 47 is formed by positioning the cut 48 in the rubber sheet 31 outside the overlapping region 49 and within a region of the second flow path 35 that does not overlap with the first branch path 41a. When negative pressure is generated in the second branch path 41b, the rubber sheet 31 of the second check valve 47 comes into close contact with the second member 33 between the overlapping region 49 and the cut 48. By coming into close contact with the second member 33, deformation of the rubber sheet 31 is restricted, and the cut 48 enters a closed state. The second check valve 47 can prevent the fluid 16 from flowing from the second flow path 35 into the second branch path 41b by closing the notch 48 of the rubber sheet 31.

[0023] As shown in FIG. 6 , when positive pressure is generated in the second branch path 41b, the rubber sheet 31 of the second check valve 47 moves away from the second member 33 between the overlap region 49 and the notch 48. This forms a gap between the rubber sheet 31 and the second member 33. The gap opens to the second flow path 35 through the notch 48. In the second check valve 47, the notch 48 of the rubber sheet 31 opens. Note that in the second check valve 47 according to this embodiment, the rubber sheet 31 around the notch 48 moves away from the xz plane, forming a gap between the rubber sheet 31 and the second member 33 and opening the valve. When open, the second check valve 47 allows the fluid 16 to flow from the second branch path 41b to the second flow path 35. The unidirectionality of the second check valve 47 is ensured by the distance D2 between the overlap region 49 and the notch 48.

[0024] The attachment 14 as described above can be formed by molding the first member 32 and the second member 33 from resin, sandwiching the rubber sheet 31 between the first member 32 and the second member 33, and then joining the first member 32, the rubber sheet 31, and the second member 33 by plasma bonding to form an integrated unit.

[0025] Next, the operation of the micropipette system 11 will be described. When a predetermined volume decrease occurs in the micropipette 12 in response to a pushing operation of the micropipette 12, positive pressure is applied from the second branch path 41b to the second check valve 47. When positive pressure is applied to the second check valve 47, the second check valve 47 allows the fluid 16 to flow from the second branch path 41b to the second flow path 35. When positive pressure is applied to the first check valve 43, the first check valve 43 blocks the flow of the fluid 16. The micropipette 12 discharges a predetermined volume of fluid 16 from the discharge nozzle 18 via the second branch path 41b and the second flow path 35.

[0026] When the pushing operation of the micropipette 12 is released and the volume of the micropipette 12 increases as determined by the pushing operation, negative pressure is applied to the first check valve 43 from the first branched channel 41a. The negative pressure applied to the first check valve 43 allows the fluid 16 to flow from the first flow path 34 to the first branched channel 41a. The negative pressure applied to the second check valve 47 blocks the flow of the fluid 16. A predetermined volume of fluid 16 flows from the reservoir 15 to the first flow path 34. The micropipette 12 can thus supply a predetermined volume of fluid 16 from the discharge nozzle 18 discretely with each pushing operation.

[0027] Prior to dispensing liquid, the pipette tip 13 is connected to the tip holder 23 of the micropipette 12. An attachment 14 is attached to the pipette tip 13 before (or after) attaching it to the tip holder 23. The tip of the pipette tip 13 is inserted into the port 42. The attachment 14 is connected to the reservoir 15 via a tube 17. The reservoir 15 holds the fluid 16 to be dispensed. When dispensing of the fluid 16 is complete, the ejector button 28 is operated. The pipette tip 13 is detached from the tip holder 23 together with the attachment 14.

[0028] When the push button 22 is pressed after the pipette tip 13 is connected, air is introduced from the variable volume chamber in the micropipette 12 into the third flow path 41 (pipette connection path 41c, first branch path 41a, and second branch path 41b) of the attachment 14. The air is discharged from the tip of the discharge nozzle 18. When the push button 22 is released, the volume of the variable volume chamber expands. As a result of this operation being repeated, air and then fluid 16 flow into the first branch path 41a of the third flow path 41, as shown in Figure 7. When the push button 22 is released, the first branch path 41a is filled with fluid 16.

[0029] When first branch path 41a is initially filled with liquid, subsequent operation of push button 22 may result in partial air remaining in second branch path 41b, as shown in Fig. 8. However, after first branch path 41a is filled with fluid 16, a predetermined volume of fluid 16 is introduced into third flow path 41 when push button 22 is released, as shown in Fig. 9. When push button 22 is pressed down, a predetermined volume of fluid 16 flows into second branch path 41b. In this way, after several push operations, attachment 14 can dispense a predetermined volume of fluid 16 from the tip of dispense nozzle 18.

[0030] According to the above configuration, the attachment 14 is provided with a pipette connection path 41c that connects to the micropipette 12, and thus can be connected to an existing micropipette 12. Furthermore, the attachment 14 can supply the fluid 16 in the reservoir 15 discretely from the first flow path 34 to the second flow path 35 connected to the discharge nozzle 18 while keeping the first flow path 34 connected to the reservoir 15 by alternately opening and closing the first check valve 43 and the second check valve 47 in response to the operation of the micropipette 12. Therefore, the attachment 14 can avoid the need for shuttle travel between the reservoir 15 and each of the individual distribution destinations, thereby reducing the burden on the user when using an existing micropipette 12.

[0031] Here, the attachment 14 can be formed by overlapping the first member 32, the rubber sheet 31, and the second member 33. Therefore, the attachment 14 has a simple structure and can be made smaller. Even when the attachment 14 is attached to the micropipette 12, the operability of the micropipette 12 can be maintained excellent. Furthermore, the first check valve 43 and the second check valve 47 are formed based on single cuts 44, 48 cut into the rubber sheet 31, respectively. Because the first check valve 43 and the second check valve 47 are formed by simply cutting the cuts 44, 48 into the rubber sheet 31, the manufacturing cost of the attachment 14 can be reduced.

[0032] In this embodiment, the first flow path 34 and the second flow path 35 are formed by closing grooves formed in the surface 32a of the first member 32 with the rubber sheet 31. Because the first flow path 34 and the second flow path 35 can be formed by processing the surface 32a of the first member 32, the manufacturing cost of the attachment 14 can be reduced. Similarly, the third flow path 41 is formed by closing grooves formed in the surface 33a of the second member 33 with the rubber sheet 31. Because the third flow path 41 can be formed by processing the surface 33a of the second member 33, the manufacturing cost of the attachment 14 can be reduced.

[0033] In the above-described embodiment, the attachment 14 is detachably attached to the pipette tip 13. However, the present invention is not limited to this. For example, the attachment 14 may have a connecting portion corresponding to the pipette tip 13 fixed to it in a non-detachable manner. FIG. 10 schematically illustrates the configuration of a micropipette system 51 according to a second embodiment of the present invention. In this second embodiment, a connecting body 52 formed of a pipette tip is fixed to an attachment 53. The attachment 53 has a configuration similar to that of the attachment 14 described above. The connecting body 52 can be fixed to the attachment 53 using, for example, an adhesive. The attachment 53 functions as a single pipette tip. The attachment 53 can be easily detachably attached to the tip holder 23 of the micropipette 12 via the connecting body 52, similar to the pipette tip 13. The attachment 53 can be easily detached from the micropipette 12 by operating the ejector button 28.

[0034] In the above-described embodiment, the attachment 14 is provided with a port 36, which is a suction port for receiving the fluid 16, on one side surface thereof, and a port 37, which is a discharge port for discharging the fluid 16 from inside the attachment 14, on the bottom surface thereof. In this configuration, the fluid 16 is sucked into the attachment 14 from the x-axis direction, which is the width direction of the attachment 14, and is discharged from inside the attachment 14 in the z-axis direction, which is the axial direction of the discharge nozzle 18 and perpendicular to the x-axis direction. However, the present invention is not limited to this. In another embodiment, for example, the attachment 14 may be provided with a port 36, which is a suction port for receiving the fluid 16, on one side surface thereof, and a port 37, which is a discharge port for discharging the fluid 16 from inside the attachment 14, on the other side surface thereof opposite the port 36 in the x-axis direction, which is the width direction of the attachment 14. Furthermore, port 36, which is a suction port that receives fluid 16 inside attachment 14, and port 37, which is a discharge port that discharges fluid 16 from inside attachment 14, may be provided in various positions, for example, on the top surface, front surface, oblique side surface, etc. of attachment 14.

[0035] FIG. 11 is a schematic diagram illustrating the configuration of a micropipette system 61 according to a third embodiment of the present invention. In this third embodiment, a port serving as an intake port for receiving fluid 16 from a reservoir 15 into the attachment 62 is provided on one side of the attachment 62. A port serving as an outlet for discharging fluid 16 from the attachment 62 is provided on the other side of the attachment 62, facing the intake port in the width direction of the attachment 62. The top surface of the attachment 62 is connected to the micropipette 12. The attachment 62 is provided with, for example, a connection tube 63 that connects a discharge nozzle 18 extending from the bottom surface of the attachment 62 to a port provided on the other side of the attachment 62. The micropipette system 61 has the same configuration as the micropipette system 11 described above, except for the attachment 62. The following description focuses on the attachment 62.

[0036] As shown in FIG. 12, the attachment 62 includes a first member 65 and a second member 66 that sandwich a rubber sheet 64 in the z-axis direction, which is the axial direction of the pipette tip 13 (discharge nozzle 18) shown in FIG. 11. The first member 65 defines a first flow path 67 connected to the reservoir 15 and a second flow path 68 connected to the discharge nozzle 18. The first flow path 67 and the second flow path 68 extend in the x-axis direction, which is the width direction of the attachment 62 and perpendicular to the z-axis direction. The second flow path 68 is separated from the first flow path 67 by a convex portion formed on the surface of the first member 65. The first member 65 is formed of, for example, a transparent material. COP resin or PDMS resin can be used as the material for the first member 65. The user can observe the movement of the fluid 16 within the first member 65. The first flow path 67 and the second flow path 68 are defined by grooves and the rubber sheet 64, similar to the first flow path 34 and the second flow path 35 described above. The rubber sheet 64 is molded from, for example, silicone resin, similar to the rubber sheet 31 described above.

[0037] The second member 66 defines a third flow path 69, which is composed of a pipette connection path 69c, a first branch path 69a, and a second branch path 69b. The pipette connection path 69c is connected to the micropipette 12. The first branch path 69a is connected to the pipette connection path 69c and the first flow path 67, and the second branch path 69b is connected to the pipette connection path 69c and the second flow path 68. The third flow path 69 is defined by a groove and a rubber sheet 64, similar to the third flow path 41 described above. The second member 66 is formed of, for example, a transparent material. COP resin or PDMS resin can be used as the material for the second member 66. The user can observe the movement of the fluid 16 within the second member 66.

[0038] A first check valve 71 is disposed between the first flow path 67 and the first branch path 69a. The first check valve 71 is formed based on a single cut 72 cut into the rubber sheet 64. The first flow path 67 and the first branch path 69a overlap at an overlapping region 73, with the rubber sheet 64 sandwiched therebetween. When forming the first check valve 71, the cut 72 is disposed outside the overlapping region 73 and within the first branch path 69a. As shown in FIG. 13 , when positive pressure is generated in the first branch path 69a, the rubber sheet 64 of the first check valve 71 comes into tight contact with the first member 65 between the overlapping region 73 and the cut 72. This tight contact restricts deformation of the rubber sheet 64. The first check valve 71 can prevent the fluid 16 from flowing from the first branch path 69a to the first flow path 67. 12, when negative pressure is generated in the first branched passage 69a, the rubber sheet 64 of the first check valve 71 moves away from the first member 65 between the overlapping region 73 and the notch 72. In this way, a gap is formed between the rubber sheet 64 and the first member 65. The gap opens to the first branched passage 69a at the notch 72. The first check valve 71 allows the fluid 16 to flow from the first flow path 67 to the first branched passage 69a. The one-way property of the first check valve 71 is ensured according to the distance D3 between the overlapping region 73 and the notch 72.

[0039] A second check valve 75 is disposed between the second flow path 68 and the second branch path 69b. The second check valve 75 is formed based on a single cut 76 cut into the rubber sheet 64. The second flow path 68 and the second branch path 69b overlap at an overlapping region 77, with the rubber sheet 64 sandwiched therebetween. When forming the second check valve 75, the cut 76 is disposed within the second flow path 68, away from the overlapping region 77. As shown in FIG. 12 , when negative pressure is generated in the second branch path 69b, the rubber sheet 64 of the second check valve 75 comes into tight contact with the second member 66 between the overlapping region 77 and the cut 76. This tight contact restricts deformation of the rubber sheet 64. The second check valve 75 can prevent the fluid 16 from flowing from the second flow path 68 into the second branch path 69b. 13, when a positive pressure is generated in the second branch path 69b, the rubber sheet 64 of the second check valve 75 moves away from the second member 66 between the overlap region 77 and the notch 76. In this way, a gap is formed between the rubber sheet 64 and the second member 66. The gap opens to the second flow path 68 at the notch 76. The second check valve 75 allows the fluid 16 to flow from the second branch path 69b to the second flow path 68. The one-way property of the second check valve 75 is ensured by the distance D4 between the overlap region 77 and the notch 76.

[0040] According to the above configuration, the attachment 62 can be connected to an existing micropipette 12 by providing a pipette connection path 69c connected to the micropipette 12. Furthermore, the attachment 62 can discretely supply the fluid 16 in the reservoir 15 from the first flow path 67 to the second flow path 68 connected to the connecting tube 63 while keeping the first flow path 67 connected to the reservoir 15 by alternately opening and closing the first check valve 71 and the second check valve 75 in response to the operation of the micropipette 12. The fluid 16 supplied to the second flow path 68 is supplied to the discharge nozzle 18 via the connecting tube 63 and discharged from the discharge nozzle 18 in the z-axis direction, which is the axial direction of the pipette tip 13 (discharge nozzle 18). Therefore, the attachment 62 can also avoid back-and-forth movement between the reservoir 15 and each distribution destination, thereby reducing the burden on the user when using an existing micropipette 12.

[0041] Furthermore, in the above-described embodiment, the attachment of the present invention is applied to a micropipette 12 as a pipette, but the present invention is not limited to this. For example, the attachment of the present invention may be applied to various other pipettes, such as a Komagome pipette or other pipettes that perform automatic dispensing.

[0042] Furthermore, in the second embodiment described above, the attachment 62 is described in which the discharge nozzle 18 extending from the bottom surface of the attachment 62 is connected to a port provided on the other side surface of the attachment 62 by a connecting tube 63, but the present invention is not limited to this. For example, as shown in Fig. 14, the other side surface of the attachment 82 may be provided with a discharge nozzle 83 curved, for example, in an L-shape. In this case, the discharge nozzle 83 of the attachment 82 is provided at a position offset from the axis of the pipette tip 13, and the fluid is discharged from the discharge nozzle 83 positioned at a position offset from the axis of the pipette tip 13. Note that the attachment 82 has the same configuration as the attachment 62 described above, and therefore a description thereof will be omitted.

[0043] In the first embodiment described above, the pipette connection path 41c is also formed in the second member 33 in which the first branch path 41a and the second branch path 41b are formed, but the present invention is not limited to this. For example, the pipette connection path connected to the pipette may be formed in the first member 32 in which the first flow path 34 and the second flow path 35 are formed, or may be formed in the first member 32 and the second member 33. In this case, a rubber sheet having holes or the like that connect the pipette connection path to the first branch path 41a and the second branch path 41b is provided. [Explanation of symbols]

[0044] 12 Micropipette (pipette) 13 Pipette Tips 14, 53, 62, 82 attachments (attachments for pipettes) 15 Reservoir 18, 83 Discharge nozzle 23 Chip holder 31, 64 Rubber sheet 32, 65 First member 33, 66 Second member 34, 67 First flow path 35, 68 Second flow path 41, 69 Third Channel 41a, 69a First Fork 41b, 69b 2nd fork 41c, 69c pipette connection channel 43, 71 First check valve 44, 48, 72, 76 notches 47, 75 Second check valve

Claims

1. a first member and a second member that sandwich a rubber sheet; a first flow path defined in the first member and connected to a reservoir; a second flow path separated from the first flow path and defined by the first member, the second flow path being connected to a discharge nozzle; a pipette connection path formed in the first member and / or the second member and connected to a pipette; a first branch channel defined by the second member and connected to the pipette connection channel and the first flow channel; a second branch channel defined by the second member and connected to the pipette connection channel and the second flow channel; Equipped with The rubber sheet a first check valve disposed between the first flow path and the first branch path and configured to allow fluid to flow from the first flow path to the first branch path; a second check valve disposed between the second flow path and the second branch path and configured to allow fluid to flow from the second branch path to the second flow path; is formed, Attachment for pipettes.

2. a third flow path defined in the second member; the third flow path is composed of the pipette connection path, the first branch path, and the second branch path, and extends from the pipette connection path and branches into the first branch path and the second branch path.

2. An attachment for a pipette according to claim 1.

3. the first check valve and the second check valve are each formed based on a cut made in the rubber sheet; 2. An attachment for a pipette according to claim 1.

4. the first flow path and the second flow path are established based on grooves formed on the surface of the first member and closed by the rubber sheet; 2. An attachment for a pipette according to claim 1.

5. the first branch path and the second branch path are established based on grooves formed on the surface of the second member and closed by the rubber sheet; 2. An attachment for a pipette according to claim 1.

6. A pipette tip that receives a tip holder of the pipette is fixed to the pipette connection path.

2. An attachment for a pipette according to claim 1.

7. The discharge nozzle is attached to the second flow path along an extension line in the axial direction of a pipette tip connected to a tip holder of the pipette.

2. An attachment for a pipette according to claim 1.

8. The surface direction of the rubber sheet is arranged along an extension line of the axial direction of the pipette tip connected to the tip holder of the pipette.

2. An attachment for a pipette according to claim 1.

Images