JP7245135B2 - Pre-wash method, liquid aspirator and pipette - Google Patents

Description

TECHNICAL FIELD The present disclosure relates to a pre-washing method for washing a pipette before aspirating a liquid to be measured by the pipette, a liquid aspirator, and a pipette.

A pipette is known that aspirates a liquid into a capillary by creating a negative pressure in the capillary (for example, Patent Document 1). The pipette disclosed in Patent Document 1 has a capillary, a pressure chamber connected to the capillary, a drive section for changing the volume of the pressure chamber, and a control section for controlling the drive section.

Patent No. 6426882

A prewashing method according to an aspect of the present disclosure includes a capillary having open first and second ends, which are both ends in the length direction, and pressure communicating with the inside of the capillary through the second end. A pre-washing method for washing the capillary of a pipette having a chamber, a driving unit for changing the volume of the pressure chamber, and an openable/closable valve connecting the pressure chamber and the outside , a liquid contacting step in which one end is brought into contact with the prewashing liquid stored in a container; after the liquid contacting step, the volume of the pressure chamber is an aspiration step of aspirating the pre-washing liquid into the capillary by controlling the drive unit so as to increase , and after the aspiration step, with the first end in contact with the pre-washing liquid, a discharge step of controlling the drive unit so as to reduce the volume of the pressure chamber to discharge the pre-wash liquid from the capillary; and a syneresis step of pulling up from the wash liquid. In the suction step, with the valve closed, the drive unit is controlled so as to increase the volume of the pressure chamber by a first increment to suck the prewash liquid into the capillary, and the discharge step Then, the valve is opened, the drive unit is controlled to increase the volume of the pressure chamber by a second increment while the valve is open, the valve is closed, and the valve is closed. The driving unit is controlled to reduce the volume of the pressure chamber by a first decrease amount whose absolute value is larger than the first increase amount, and the prewash liquid is discharged from the capillary.

A liquid suction device according to an aspect of the present disclosure includes a pipette structure, a movement mechanism for relatively moving a pipette structure, and a container storing liquid to be sucked into the pipette structure, the pipette structure, and a control unit for controlling the movement mechanism, the pipette structure unit includes a capillary having first and second ends, which are both ends in the length direction, and a capillary through the second end. a pressure chamber that communicates with the inside of the capillary, a drive unit that changes the volume of the pressure chamber , and an openable/closable valve that connects the pressure chamber and the outside ; moving the first end into the container, increasing the volume of the pressure chamber by a first increment with the valve closed, with the first end positioned within the container ; After increasing by one increment, the volume of the pressure chamber is increased by a second increment with the valve open, and after increasing by the second increment, with the valve closed, the volume of the pressure chamber is increased by the second increment. The moving mechanism , the driving unit , and the moving mechanism , the driving unit , and controlling the valve ;

A pipette according to an aspect of the present disclosure includes a capillary that is open at first and second ends, which are both longitudinal ends, and a pressure chamber that communicates with the inside of the capillary through the second end. , a drive unit that changes the volume of the pressure chamber, a valve that can be opened and closed that connects the pressure chamber and the outside, and a control unit that controls the drive unit and the valve , the control unit comprising: , a timetable that defines the operation of the drive unit is stored, the drive unit and the valve are controlled according to the timetable, and the timetable stores the volume of the pressure chamber with the valve closed. is increased by a first increment, after the increase by the first increment, the volume of the pressure chamber is increased by a second increment with the valve open, and the increase by the second increment After that, it defines an operation of decreasing by a first decreasing amount whose absolute value is larger than the first increasing amount while the valve is closed .

1 is a cross-sectional view schematically showing an example of a pipette of the present disclosure; FIG. 2 is a block diagram showing the configuration of a control unit of the pipette of FIG. 1; FIG. FIG. 3 is a schematic diagram showing an example of a timetable stored by a control unit in FIG. 2; FIG. 3 is a graph schematically showing an example of a waveform of a drive signal output by the control section of FIG. 2; 5 is a graph showing a continuation of FIG. 4; 2 is a table outlining the steps performed by the pipette of FIG. 1; 7(a), 7(b), 7(c) and 7(d) are schematic cross-sectional views for explaining the pre-washing step. It is a figure which expands and shows a part of FIG. 2 is a schematic perspective view showing the appearance of a liquid suction device including the pipette of FIG. 1. FIG. FIG. 10 is a flow chart showing a main part of an example of a procedure of processing executed by the liquid suction device of FIG. 9; FIG.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The drawings used in the following description are schematic, and the dimensional ratios and the like on the drawings do not necessarily match the actual ones. Dimensional ratios and the like may not match each other even among a plurality of drawings.

In the present disclosure, the terms "water repellency" or "hydrophilicity" may be used for both absolute evaluation and relative evaluation of properties.

For example, "has water repellency" refers to a contact angle of 90° or more with respect to a liquid to be aspirated by a pipette (absolute evaluation). Further, for example, "has hydrophilicity" means that the contact angle of the liquid to be aspirated by the pipette is less than 90°. If the liquid to be aspirated by the pipette is not specified, the contact angle of water may be used to determine the presence or absence of water repellency or hydrophilicity.

On the other hand, for example, "high water repellency", "low water repellency", or "different water repellency" means that two members that come into contact with the liquid to be aspirated by the pipette (which may be water as described above) When the contact angles of the liquid are compared, one contact angle is larger, smaller, or different from the other contact angle (relative evaluation). Therefore, for example, when the water repellency of the first member is higher than the water repellency of the second member, both the first member and the second member, or the second member need not have water repellency. It may have hydrophilicity.

[Outline of pipette]
FIG. 1 is a cross-sectional view (partially a side view and a block diagram) schematically showing the configuration of a pipette 1 according to an embodiment of the present disclosure. In the drawing, for convenience, the pipette 1 is given a fixed orthogonal coordinate system xy. The +x side (lower side of the paper) is the side that is downward when the pipette 1 aspirates liquid. Note that the pipette 1 is not always used in a posture parallel to the vertical direction.

The pipette 1 includes, for example, a capillary 10, a pipette body 20 that changes the air pressure in the capillary 10, a control section 24 that controls the operation of the pipette body 20, and a signal according to a user's operation to the control section 24. and an operation unit 25 . A combination of the capillary 10 and the pipette body 20 is sometimes referred to as a pipette structure 15 .

In the pipette 1, for example, the inside of the capillary 10 is evacuated from the rear end (second end 12) of the capillary 10 by the pipette body 20 while the +x side tip (first end 11) of the capillary 10 is in contact with the liquid. Liquid is thus sucked into the capillary 10 . From another point of view, the liquid moves from the first end 11 side to the second end 12 side. Conversely, when air is supplied from the second end 12 into the capillary 10 by the pipette body 20, the liquid moves from the second end side to the first end 11 side.

[capillary]
The capillary 10 has a cylindrical shape with a first end 11 and a second end 12, which are both ends in the length direction (x direction), open. The term “cylindrical shape” means, for example, a shape that is long in one direction (the length in the one direction is longer than the length in the other direction), is hollow, and is open at both ends. It does not mean only cylindrical.

The general shape of capillary 10 may be of various shapes. For example, in the cross section of the capillary 10 (cross section orthogonal to the length direction; hereinafter the same), the shape of the inner edge (inner surface of the capillary 10) and/or the outer edge (outer surface of the capillary 10) is circular, elliptical, or oval. Or it may be a polygon or the like. Further, for example, the shape and/or size of the cross section (inner edge and/or outer edge) may be constant over the entire length of the capillary 10, or may be the same in the longitudinal direction over at least part of the entire length of the capillary 10. It may be different depending on the position. Also, for example, in the cross section of the capillary 10, the inner edge and the outer edge may or may not have similar shapes to each other. Also, for example, the center line of the internal space (channel) of the capillary 10 may extend linearly from the first end 11 to the second end 12, or may be curved at least partially.

In the description of the present embodiment, for the sake of convenience, it is assumed that the cross section (inner edge and outer edge) of the capillary 10 is circular at any position in the length direction. In this case, the cross-sectional shape of the hole of the capillary 10 is the same or similar (including congruent) at different positions in the length direction of the capillary 10 . When it is said that the inner diameters are different at mutually different positions in the length direction of the capillary 10, the area of the cross section is the same regardless of whether the cross-sectional shapes of the holes at the mutually different positions are similar or dissimilar. It can be taken to mean that they are different from each other.

The dimensions of the capillary 10 may be appropriately set according to various circumstances such as the amount of liquid to be sampled and/or the method of attachment to the pipette body 20 . For example, the inner diameter of the capillary 10 may be 0.1 mm or more and 0.3 mm or less. Also, for example, the outer diameter of the capillary 10 may be 0.4 mm or more and 1.2 mm or less. Also, for example, the length of the capillary 10 may be 20 mm or more and 100 mm or less.

The material of capillary 10 may vary. Examples of such materials include glass, resins, ceramics, and metals. Further, for example, the capillary 10 may be made of different materials in a part and other parts in the longitudinal direction, and/or made of different materials in a part and other parts in the radial direction. may be Conversely, the capillary 10 may be integrally constructed of the same material almost entirely. Further, for example, the capillary 10 may be configured by forming a film made of another material on at least part of the surface of a member made of one material. Also, for example, at least part (that is, part or all) of the capillary 10 may be made of a translucent material (eg, resin or glass).

At least part of the surface of the capillary 10 (that is, part or all) may have water repellency. A region having water repellency on the surface of the capillary 10 may be appropriately set. For example, the region having water repellency includes the end face of the first end 11 (the face facing the +x direction), a part of the inner surface of the capillary 10 on the +x side, and a part of the outer surface of the capillary 10 on the +x side. I'm in. In other words, the water-repellent region includes the liquid-contacting region. Having water repellency in the liquid-contacting region reduces, for example, the probability of unintended adhesion and/or movement of the liquid, and improves the accuracy of the amount of liquid sampled. The water repellency may be uniform or may vary along the length and/or about the axis of capillary 10 .

The capillary 10 (partially or entirely) may have a water-repellent surface, for example, by being made of a water-repellent material. Further, for example, the capillary 10 (partially or wholly) may have water repellency on its surface by forming a water repellent film on the surface of a member made of a material that does not have water repellency.

Various types of water-repellent films may be used, and examples thereof include a water-repellent film formed with a silane coupling agent, a metal alkoxide-containing water-repellent film, a silicone-containing water-repellent film, and a fluorine-containing water-repellent film. can be done. Various methods may be used to form the water-repellent film on the surface of the capillary 10. For example, a dry process method or a wet process method may be used. Dry process methods include, for example, physical vapor deposition and chemical vapor deposition. The former includes, for example, physical vapor deposition and sputtering. The latter include, for example, chemical vapor deposition (CVD) and atomic layer deposition (ALD) methods. Wet process methods include, for example, a sol-gel method, a dip coating method, and a coating method.

The capillary 10 is disposable, for example, and is detachable from the pipette body 20 . The attaching/detaching method may be an appropriate method. For example, the capillary 10 may be fixed by being press-fitted into the hole of the pipette body 20, or may be fixed by tightening or locking by a mechanism (not shown) provided in the pipette body 20. However, the capillary 10 may be used repeatedly, or may be non-detachably fixed (for example, adhered) to the pipette body 20 .

In the illustrated example, the capillary 10 has a glass tube 13 and a resin tip member 14 fixed to the tip of the glass tube 13 . Resin generally has high water repellency, and has higher water repellency than glass. Therefore, the capillary 10 has water repellency on the first end 11 side, and the water repellency on the first end 11 side is higher than that on the second end 12 side. Further, the glass tube 13 has higher translucency than the chip member 14, for example. This makes it easier to irradiate the sample liquid in the glass tube 13 with light.

The shapes of the glass tube 13 and the tip member 14 may be appropriately set. In the illustrated example, the glass tube 13 extends linearly with a constant diameter (constant cross section). On the other hand, the tip member 14 is tapered such that the diameter becomes smaller toward the distal end. The glass tube 13 is inserted from behind and fixed to the tip member 14 . Among the through-holes of the capillary 10, a step is formed at the boundary between the hole 10b formed by the glass tube 13 and the hole 10a formed by the tip member 14 because the latter is larger.

[Pipette body]
The pipette body 20 has a pressure chamber 21 (cavity) communicating with the inside of the capillary 10 . The pipette body 20 increases the volume of the pressure chamber 21 to reduce the pressure (exhaust) within the capillary 10, and decreases the volume of the pressure chamber 21 to increase the pressure (air supply) within the capillary 10. conduct. As a result, for example, liquid suction and discharge by the capillary 10 are realized. The configuration of the pipette body 20 that realizes such operations may be made as appropriate. An example is shown below.

The pipette body 20 includes, for example, a channel member 35 that forms a channel (including the pressure chamber 21) communicating with the inside of the capillary 10, an actuator 40 that changes the volume of the pressure chamber 21, and a channel member. It has a valve 23 that permits and prohibits communication between the interior (flow path) of 35 and the exterior.

(Flow path member)
The general shape and size of the flow path member 35 may be appropriately shaped. In the illustrated example, the outline of the channel member 35 is in the shape of an axis in series with the capillary 10 (the length in the x direction is longer than the length in the other directions). In addition, the size is, for example, a size that can be picked up or gripped by a user (for example, the maximum outer diameter is 50 mm or less).

The internal space of the channel member 35 includes, for example, the pressure chamber 21, the communication channel 27 connecting the capillary 10 and the pressure chamber 21, the communication channel 27 (from another point of view, the pressure chamber 21), and the outside. It has an open channel 28 that connects.

The shape, position, size, etc. of the pressure chamber 21 may be appropriately set. In the illustrated example, the pressure chamber 21 is located on the side surface of the flow path member 35 . Further, for example, the general shape of the pressure chamber 21 is a thin shape with a substantially constant thickness, with the thickness direction being the direction overlapping the actuator 40 (the y direction). A thin shape here is a shape in which the length in the y direction is shorter than the maximum length in each direction orthogonal to the y direction. The planar shape of the pressure chamber 21 (the shape when viewed in the y direction) may be an appropriate shape such as a circle, an ellipse, a rectangle, or a rhombus. The thickness (y direction) of the pressure chamber 21 is, for example, 50 μm or more and 5 mm or less. The diameter of the pressure chamber 21 (maximum length in each direction perpendicular to the y direction) is, for example, 2 mm or more and 50 mm or less.

The shape, position, size, etc. of the communication channel 27 and the open channel 28 may also be appropriately set. For example, the channel member 35 includes the first channel 22 extending from the capillary 10 in the length direction (x direction) of the capillary 10 and the direction intersecting the first channel 22 from the middle of the first channel 22 . and a second flow path 26 extending to the pressure chamber 21 . A communication channel 27 is formed by the second channel 26 and a portion of the first channel 22 on the side of the capillary 10 from the connection position with the second channel 26 . With such a flow path configuration, for example, the possibility that the sucked liquid (for example, its droplets) enters the pressure chamber 21 and adheres to the actuator 40 is reduced. As a result, the probability that the operating characteristics of the actuator 40 change due to the adhering liquid is reduced.

Also, the first channel 22 communicates with the outside of the channel member 35 on the side opposite to the capillary 10, for example. An open channel 28 is formed by a portion of the first channel 22 on the side opposite to the capillary 10 from the connection position with the second channel 26 . Therefore, the flow path for releasing the liquid so that the liquid does not enter the pressure chamber 21 is also used as the open flow path 28 for opening the pressure chamber 21 to the outside, thereby improving space efficiency.

The cross-sectional shape and dimensions of the first channel 22 and the second channel 26 may be set as appropriate. For example, the cross sections of the first channel 22 and the second channel 26 are circular with a diameter of 0.1 mm or more and 1 mm or less. Also, the inner diameters of the first channel 22 and the second channel 26 may be the same or different. The cross-sectional shape and size of the first channel 22 and/or the second channel 26 may be constant or may vary along its length.

The flow path member 35 may be configured by combining members having appropriate shapes and made of appropriate materials. In the illustrated example, the channel member 35 has a first part 30 and a second part 60 joined together. The first part 30 has a through hole that serves as the pressure chamber 21 . The second part 60 has a first channel 22 and a second channel 26 . The pressure chamber 21 is configured by a space surrounded by the first part 30 , the second part 60 and the actuator 40 . Note that each of the first part 30 and the second part 60 may also be configured by combining a plurality of members. The material of the first part 30 and the second part 60 may be, for example, metal, ceramic or resin, or any combination thereof.

(actuator)
The actuator 40 constitutes one of the inner surfaces of the pressure chamber 21, for example. Specifically, for example, the actuator 40 has a substantially plate shape, is joined to the first part 30 so as to close the through hole of the first part 30 from the side opposite to the second part 60, and has a communication channel. It constitutes the inner surface opposite to the inner surface where 27 opens. The actuator 40 reduces the volume of the pressure chamber 21 by bending toward the pressure chamber 21 (in other words, displacing the inner surface of the pressure chamber 21 inward). Conversely, the actuator 40 increases the volume of the pressure chamber 21 by bending in the opposite direction to the pressure chamber 21 (in other words, by displacing the inner surface of the pressure chamber 21 outward).

The specific configuration of the actuator 40 that causes bending deformation as described above may be made as appropriate. For example, the actuator 40 is configured by a unimorph-type piezoelectric element. More specifically, for example, the actuator 40 has two laminated piezoelectric ceramic layers 40a and 40b. The actuator 40 also has an internal electrode 42 and a surface electrode 44 facing each other with the piezoelectric ceramic layer 40a interposed therebetween. The piezoelectric ceramic layer 40a is polarized in the thickness direction.

When a voltage is applied to the piezoelectric ceramic layer 40a by the internal electrode 42 and the surface electrode 44 in the same direction as the polarization direction, the piezoelectric ceramic layer 40a contracts in the planar direction. On the other hand, the piezoceramic layer 40b does not experience such shrinkage. As a result, the piezoelectric ceramic layer 40a bends toward the piezoelectric ceramic layer 40b. That is, the actuator 40 bends toward the pressure chamber 21 side. When a voltage opposite to the above is applied, the actuator 40 bends to the side opposite to the pressure chamber 21 .

The shape, size, etc. of the actuator 40 may be appropriately set. For example, the actuator 40 has an appropriate flat plate shape. The planar shape may or may not be similar to the planar shape of the pressure chamber 21 . The maximum length in each direction in plan view (seen in the y direction) is, for example, 3 mm or more and 100 mm or less. The thickness (y direction) of the actuator 40 is, for example, 20 μm or more and 2 mm or less. The materials, dimensions, shapes, conduction methods, and the like of various members that constitute the actuator 40 may also be appropriately set. An example is shown below.

The thickness of the piezoelectric ceramic layers 40a and 40b may be, for example, 10 μm or more and 30 μm or less. The material of the piezoelectric ceramic layers 40a, 40b may be, for example, a ferroelectric ceramic material. Examples of such ceramic materials include those based _on lead zirconate titanate (PZT), _NaNbO3 , KNaNbO3, _{BaTiO3 ,} (BiNa) _NbO3 , and _BiNaNb5O15 . The piezoelectric ceramic layer 40b may be made of a material other than a piezoelectric material.

The internal electrode 42 is positioned, for example, between the piezoelectric ceramic layer 40 a and the piezoelectric ceramic layer 40 b and has approximately the same size as the actuator 40 . The thickness of the internal electrode 42 may be, for example, 1 μm or more and 3 μm or less. The internal electrode 42 can be electrically connected from the outside by, for example, a through electrode 48 penetrating the piezoelectric ceramic layer 40 a and a connection electrode 46 located on the surface of the actuator 40 and connected to the through electrode 48 .

The surface electrode 44 is positioned, for example, on the side of the piezoelectric ceramic layer 40a opposite to the piezoelectric ceramic layer 40b (outside the pressure chamber 21), and has a surface electrode body 44a and a lead electrode 44b. The surface electrode main body 44a has, for example, a planar shape substantially equal to that of the pressure chamber 21, and is provided so as to overlap the pressure chamber 21 in the thickness direction. The extraction electrode 44b is formed so as to be extracted from the surface electrode body 44a. The thickness of the surface electrode 44 may be, for example, 0.1 μm or more and 1 μm or less.

Materials for the internal electrodes 42, the surface electrodes 44, the connection electrodes 46, and the through electrodes 48 may be metal materials, for example. More specifically, for example, the material of the internal electrodes 42 and the through electrodes 48 may be Ag--Pd. The material of the surface electrode 44 and the connection electrode 46 may be Au, for example.

The actuator 40 or a portion of the actuator 40 (for example, the portion overlapping the surface electrode main body 44a) may be referred to as a driving portion 50. As shown in FIG. The actuator is not limited to a unimorph-type piezoelectric element. For example, the actuator may be a bimorph piezoelectric element or an electrostatic actuator.

(valve)
The valve 23 is provided, for example, at a position (opening 28a) where the open channel 28 communicates with the outside. The opening and closing of the valve 23 permits or prohibits communication between the inside and the outside of the channel member 35 . When the communication is prohibited, pressure reduction and pressure increase in the capillary 10 are performed by a change in the volume of the pressure chamber 21 . On the other hand, when the communication is allowed, even if the volume of the pressure chamber 21 is changed, the pressure in the capillary 10 is neither reduced nor increased. An example of utilization of the effect of not performing pressure reduction or pressure increase will be described later.

The outside referred to here is, for example, simply speaking, the outside of the pipette 1 . Further, when the opening 28a or the valve 23 communicates with the outside, the opening 28a or the valve 23 need not be directly exposed to the outside of the pipette 1, as understood from FIG. That is, they may communicate with the outside through a gap in the channel member 35 (for example, the housing thereof) of the pipette 1 .

Also, in terms of the above operation of the valve 23, the outside refers to a space having a pressure equivalent to the pressure at the first end 11, for example, when not immersed in liquid. In other words, considering the state in which the first end 11 is immersed in liquid, the outside refers to a space having a pressure equivalent to the surrounding pressure of the capillary 10 . The pressure around capillary 10 is, for example, atmospheric pressure. However, the pressure may be pressure reduced or increased from atmospheric pressure.

The valve 23 performs an opening/closing operation according to, for example, a signal input from the outside. Various valves such as an electromagnetic valve or a piezoelectric valve can be used as the valve 23 . The valve 23 may be closed when no signal is input and open when a signal is input, or may be open when no signal is input and when a signal is input. It may be in a closed state, or a signal for closing and a signal for opening may be input.

In the illustrated example, the valve 23 has, for example, a closing component 61 that directly contributes to the opening and closing of the opening 28a of the open channel 28, and a valve driver 62 for driving the closing component 61. are doing.

The closing part 61 is movable between a closed position (position shown in FIG. 1) that closes the opening 28a and an open position that is retracted from the closed position (position moved upward from the position shown in FIG. 1). The valve drive unit 62 is configured by combining an electromagnetic drive unit and a spring drive unit, although not shown, for example. When the signal (electric power) is not input, the valve drive unit 62 moves the closing part 61 to the closed position by the restoring force of the spring, and when the signal is input, the closing part 61 is moved by the solenoid. Move to open position.

[Control part]
The control unit 24 is electrically connected to the actuator 40 and changes the volume of the pressure chamber 21 by applying an electric signal to the actuator 40 to deform the actuator 40 . As a result, the liquid can be sucked into the capillary 10 and the liquid can be discharged from the capillary 10 . By driving the actuator 40 so that the volume of the pressure chamber 21 increases and decreases periodically, the liquid sucked into the capillary 10 can be vibrated.

The control unit 24 is electrically connected to the valve 23 and opens and closes the valve 23 by giving an electric signal to the valve 23 . If liquid has flowed into the first channel 22 , the liquid can be discharged from the valve 23 to the outside by opening the valve 23 . Further, after deforming the actuator 40 to suck the liquid, the valve 23 is opened, the deformation of the actuator 40 is restored in this state, and after the valve 23 is closed, the actuator 40 is deformed again. of liquid can be inhaled.

FIG. 2 is a block diagram showing an example of the configuration of the control section 24. As shown in FIG. The control unit 24 includes, for example, a CPU (Central Processing Unit) 71, a ROM (Read Only Memory) 72, a RAM (Random Access Memory) 73, an external storage device 74, and the like. Various functional units that perform various operations are constructed by the CPU 71 executing programs stored in the ROM 72 and/or the external storage device 74 (here, the operation program 75 stored in the external storage device 74 is exemplified). be done. A part or all of these various functional units may be regarded as the control unit 24 . In the following description, the ROM 72, RAM 73 and external storage device 74 may be collectively referred to as memory.

The control unit 24 may be configured by, for example, one or more ICs (Integrated Circuits). The control unit 24 may be fixedly provided on the pipette body 20 , may be provided to be movable relative to the pipette body 20 , or may be partially fixed to the pipette body 20 (for example, a driver). and another portion (for example, a portion that outputs commands to the driver) may be provided so as to be relatively movable with respect to the pipette body 20 .

The external storage device 74 holds operation regulation information 76 that regulates the operations of the drive unit 50 and the valve 23 . Unlike the illustrated example, part or all of the operation regulation information 76 may be stored in the ROM 72 (or RAM 73). A part or all of the operation regulation information 76 may be included in data (data in a narrow sense distinguished from programs) or may be included in programs executed by the CPU 71 . Note that in the present disclosure, the word data may be used in a broad sense, such as expressing a program as a collection of data. The operation regulation information 76 is stored in memory in advance by the manufacturer of the pipette 1, for example. The action regulation information 76 may be partially or wholly changeable by the user by operating the operation unit 25 or the like.

As will be explained later with reference to FIGS. 4-6, pipette 1 can, for example, sequentially perform a plurality of steps (SA-SK). The action defining information 76 includes, for example, a plurality of pieces of information (DA to DK) defining the actions of the actuator 50 and/or the valve 23 in the plurality of steps (SA to SK). One piece of information corresponds to one step. For example, the pre-washing information DB corresponds to a pre-washing step SB in which a pre-washing liquid for washing is sucked into the capillary 10 and discharged from the capillary 10 before the liquid to be measured is sucked into the capillary 10. .

At least one of the plurality of information (DA to DK) (eg, all of DA to DK) defines, for example, the order of a series of operations of the actuator 50 and/or the valve 23 . The control unit 24 sequentially outputs a series of signals corresponding to a series of operations to the driving unit 50 and/or the valve 23 according to such information.

The plurality of operations included in the series of operations referred to herein include, for example, an operation to increase the volume of the pressure chamber 21, an operation to decrease the volume, an operation to maintain the volume of the pressure chamber 21, and these operations. include the initiation, continuation and completion of Further, for example, the valve 23 includes an opening operation and a closing operation. As the above mentions not only the action of changing the volume, but also its initiation, continuation and completion, the action that is conceived as one of a plurality of actions may be subdivided as appropriate.

FIG. 3 is a conceptual diagram showing an example of each configuration of a plurality of pieces of information (DA to DK). Here, among the plurality of information (DA to DK), the prewash information DB is taken as an example.

At least one of the plurality of pieces of information (DA to DK) (for example, all except DA and DK) is held by a timetable that associates the operation of the drive unit 50 and the operation of the valve 23 with the elapsed time. Such information defines not only the mutual order, but also the respective timing and the mutual timing, of the operation of the actuator 50 and the operation of the valve 23 . The control unit 24 sequentially outputs a series of multiple signals corresponding to a series of multiple operations to the driving unit 50 and the valve 23 according to the timetable. As a result, the drive unit 50 and the valve 23 automatically perform a series of operations (without waiting for an operation on the operation unit 25).

In the illustrated example, the column "time" on the left shows information corresponding to the elapsed time held by the timetable. Time elapses from the upper row on the page to the lower row on the page. The top row corresponds, for example, to the starting point of the action defined by the timetable. The bottom row corresponds, for example, to the time of completion of the action defined by the timetable. The symbols (t3 to t8) here correspond to the symbols shown on the horizontal axis in FIGS. 4 and 5, which will be described later.

The center column "drive unit" shows information corresponding to the operation of the drive unit 50 held in the timetable. Specifically, the signal level (for example, voltage) of the signal input from the control section 24 to the driving section 50 is held in the timetable. The symbols (Va0 to Va3) here correspond to the symbols shown in FIGS. 4 and 5, which will be described later.

The column "Valve" on the right shows information corresponding to the operation of the valve 23 held by the timetable. Specifically, the signal level (for example, voltage) of the signal input from the control unit 24 to the valve 23 is held in the timetable. The symbols (Vb0 and Vb1) here correspond to the symbols shown in FIGS. 4 and 5, which will be described later.

The time point, the operation (voltage) of the driving unit 50, and the operation (voltage) of the valve 23 shown in the same row are stored in association with each other so that the other two can be identified from the time point. ing. For example, when the control unit 24 refers to the timetable and determines that the time specified in the timetable has arrived, the voltages of the drive unit 50 and the valve 23 stored in association with that time are specified. do. The control unit 24 then generates a signal having the specified voltage and outputs it to the driving unit 50 and the valve 23 .

FIG. 3 is only a conceptual diagram, and an actual timetable may be constructed appropriately. Also, the operation of the control unit 24 may be appropriately set according to the configuration of the timetable.

For example, the timetable may be configured as data separate from the program executed by the CPU 71, or may be incorporated within the program.

Further, for example, in FIG. 3, only the points of time that become the turning point of the operation described later with reference to FIGS. 4 and 5 are listed as the points of time. In the case of such a timetable, the control unit 24 may appropriately specify the voltage of the signal at points in time between points of time by interpolation calculation.

Further, for example, unlike the above, the voltage information of the signal corresponding to each point in time may be held at regular time intervals regardless of whether or not it is such a turning point. In this case, the control unit 24 may, for example, sequentially identify the voltage corresponding to each point in the above-described time increments, and output a signal having the identified voltages over the above-described time increments. In addition, the control unit 24 may specify the voltage of the signal between the above time steps by appropriate interpolation calculation. When information is held in a timetable at fixed time intervals, only the operation of the drive unit 50 and the operation (voltage) of the valve 23 are stored in chronological order so that they can be read out, and the information at that point in time is not stored. good too.

Also, for example, the timetable may be divided into a plurality of sections. For example, a timetable in which time points and operations of the drive unit 50 are associated with each other, and a timetable in which time points and operations of the valve 23 are associated with each other may be stored separately. Then, the two timetables may function substantially like one timetable by the control unit 24 referring to both substantially in parallel and outputting signals to the drive unit 50 and the valve 23. . In the present disclosure, a timetable in which both the operation of the drive unit 50 and the operation of the valve 23 are associated with the elapsed time includes such a substantially single timetable.

Further, for example, a time table in which time points and symbols indicating the operation of the valve 23 are associated and stored, and a table in which the above symbols and the voltage of the signal output to the valve 23 are associated. may be prepared. Then, the control unit 24 may output a signal to the valve 23 by referring to both. In such a case, only the former may be regarded as a timetable, or a combination of both may be regarded as a timetable. Although the valve 23 has been described, the same applies to the drive unit 50 as well.

Also, for example, any two or more of the plurality of information (DA to DK) may be held in one timetable. For example, as will be understood from the description below, the residual pressure release information DC and the pre-operation information DD may be held by one timetable. Then, the control unit 24 sequentially specifies the voltages of the driving unit 50 and the valve 23 associated with the time points without distinguishing between the residual pressure release information DC and the pre-operation information DD included in the time table. may perform signal generation and output. Although the residual pressure release information DC and the pre-operation information DD are given as examples, information (DH to DJ) corresponding to other steps that may be automatically started according to the passage of time is also information of the previous steps. (DG-DI) may be held by the same timetable.

Information that is not held in the form of a timetable (eg DA and DK) may be included in data in an appropriate form (in a broad sense). For example, such information determines whether or not a predetermined signal has been input from the operation unit 25, and when it is determined that a predetermined signal has been input, the operation of outputting a predetermined signal to the driving unit 50 and/or the valve 23 is realized. may be included in the program.

[Operation part]
The operation part 25 may be fixedly provided on the pipette body 20 , may be provided movably relative to the pipette body 20 , or may be partially fixedly provided on the pipette body 20 . , other parts may be provided so as to be relatively movable with respect to the pipette body 20 . The configuration of the operation unit 25 may be made appropriate. For example, the operation unit 25 may be configured with one or more switches.

The number of types of signals that can be output by the operation unit 25 (from another point of view, the types of operations that can be accepted) and the number of operations that the control unit 24 executes using signals from the operation unit 25 as triggers All may not correspond, and all may correspond. For example, to give an extreme example of the former, the operation unit 25 may have only one switch. Then, the control unit 24 may proceed to the next predetermined operation according to the type of operation being executed when the signal is input from the switch. To give an extreme example of the latter, the operation unit 25 may be provided with a plurality of different switches that correspond one-to-one to a plurality of operations triggered by a signal from the operation unit 25 . Then, if the operation corresponding to the type of the input signal is an operation that is currently permitted to be executed, the control unit 24 may execute the operation. In the following description, it is possible to express that the user performs a predetermined operation on the operation unit 25, that a predetermined signal is input from the operation unit 25 to the control unit 24, etc., without distinguishing between the two. be. Although the signal from the operation unit 25 has been described, the same applies to other signals input from the outside of the pipette 1 (for example, a signal from the control unit 105 (FIG. 9) which will be described later).

[Pipette movement]
An example of the operation of the pipette 1 will be described. The operations described below are performed, for example, in an environment where the pressure of the atmosphere around the pipette 1 is constant. The pressure of the surrounding atmosphere is, for example, atmospheric pressure. However, the pressure of the surrounding atmosphere may be lower or higher than the atmospheric pressure.

4 and 5 are graphs schematically showing an example of the waveform of the driving signal output by the control section 24. FIG. The waveform of the drive signal is, in other words, the change over time of the signal level (for example, voltage) of the drive signal. In these figures, the horizontal axis t indicates time. As understood from the horizontal axis t, FIG. 5 shows a continuation of FIG. The vertical axis V indicates voltage as a signal level. The lines in the drawing indicate the waveform of the first drive signal SgA output by the controller 24 to the actuator 40 and the waveform of the second drive signal SgB output by the controller 24 to the valve 23 .

The signal level of the first drive signal SgA that the controller 24 outputs to the actuator 40 is voltage (or a physical quantity correlated with the voltage). On the other hand, the actuator 40 bends by a deformation amount corresponding to the applied voltage. The correspondence here is, for example, one-to-one correspondence, in other words, a relationship in which the amount of deformation is uniquely defined with respect to the voltage (except for a state in which the deformation is saturated). Therefore, the actuator 40 to which the first drive signal SgA is input changes the waveform of the first drive signal SgA (change in voltage over time) so that the volume of the pressure chamber 21 corresponds to the voltage of the first drive signal SgA. ), the volume of the pressure chamber 21 is changed.

Note that the relationship between the amount of change in the voltage of the first drive signal SgA and the amount of change in the volume of the pressure chamber 21 is not necessarily proportional. However, for the sake of convenience, the description will be made assuming a proportional or nearly proportional relationship. Therefore, FIGS. 4 and 5 may be regarded as showing not only the change over time of the voltage of the first drive signal SgA but also the change over time of the volume of the pressure chamber 21 .

One of the internal electrode 42 and the surface electrode 44 is supplied with a reference potential, and the other is supplied with the first drive signal SgA. 4 and 5 indicate the potential difference between the reference potential and the first drive signal SgA. In other words, the first drive signal SgA is an unbalanced signal. However, the first drive signal SgA may be a balanced signal in which the potentials of both the internal electrode 42 and the surface electrode 44 are changed and the potential difference is the voltage shown in FIGS. In the present embodiment, the case where the first drive signal SgA is an unbalanced signal is taken as an example, so the voltages in FIGS. 4 and 5 may be described below as the potential of the first drive signal SgA.

An increase in the voltage of the first drive signal SgA (change in potential to the positive side) may correspond to an increase in the volume of the pressure chamber 21, or may correspond to a decrease in the volume of the pressure chamber 21. . In other words, the direction from the internal electrode 42 and the surface electrode 44 to which the first drive signal SgA is applied to the electrode to which the reference potential is applied is opposite to the polarization direction of the piezoelectric ceramic layer 40a. may be in the same direction. For the sake of convenience, it is hereinafter assumed that an increase in the voltage of the first drive signal SgA corresponds to an increase in the volume of the pressure chamber 21 (that is, suction of liquid).

The signal level (for example, voltage) of the second drive signal SgB that the control unit 24 outputs to the valve 23 is, for example, one of two voltages Vb0 and Vb1 corresponding to the open state and the closed state of the valve 23 . Either of the two voltages may correspond to the open state or the closed state, but in the following description, the case where the voltage Vb0 is the closed state and the voltage Vb1 is the open state will be taken as an example. The second drive signal SgB, like the first drive signal SgA, may be a balanced signal or an unbalanced signal. 2 may be described as the potential of the drive signal SgB. One of the potentials Vb0 and Vb1 may be used as a reference potential. Unlike the illustrated example, the voltage of the second drive signal SgB may be a voltage between the voltages Vb0 and Vb1 so as to adjust the opening of the valve 23 .

The relative relationship between the potential of the first drive signal SgA and the potential of the second drive signal SgB may be set appropriately. In the following, for convenience, the potential Va0 of the first drive signal SgA at time t0 and the already-described potential Vb0 of the second drive signal SgB are shown as the same value. In practice, the two may be different. The actual difference between the other potentials of the first drive signal SgA and the potential Vb1 described above is not illustrated either.

When the potential of the first drive signal SgA is a predetermined potential (for example, potential Va0), the predetermined potential may be a reference potential. At this time, the control section 24 may operate not to output the first drive signal SgA. Similarly, when the potential of the second drive signal SgB is a predetermined potential (for example, potential Vb0), the predetermined potential may be the reference potential. At this time, the control section 24 may operate not to output the second drive signal SgB. In the following description, a mode in which the potentials Va0 and Vb0 are the reference potentials (a mode in which no signal is output at the potentials Va0 and Vb0) is taken as an example. However, for the sake of convenience, even when no signal is output, it may be expressed that the signal is output at the potential Va0 or Vb0.

In the following, not only the operation of the pipette 1 itself, but also the operation performed by the user of the pipette 1 or the device using the pipette 1 (for example, the liquid suction device 101 described later) will be described. Here, a mode in which the user operates the pipette 1 will be mainly described as an example. The user's operation on the pipette 1 may be appropriately read as the operation on the pipette 1 of the device. For example, movement of the pipette 1 by the user may be movement of the pipette 1 by a device (more specifically, for example, a movement mechanism 103 described later). Further, for example, the operation of a switch (not shown) of the pipette 1 by the user causes the pipette 1 (specifically, for example, the control unit 24, or the driving unit 50 and the valve 23) to be controlled by the device (specifically, for example, the control unit 105 or 106, which will be described later). ) may be output as a signal for The device may, for example, perform the same operation on the pipette as the user does by sequence control.

(multiple steps)
In the pipette 1, a plurality of steps (SA to SK) are sequentially executed by outputting drive signals shown in FIGS. In FIGS. 4 and 5, the arrows parallel to the horizontal axis with symbols SA to SK indicate the period during which each step is performed. In each step, for example, a series of operations are performed by the drive unit 50 and/or the valve 23 .

In the description here, each step is basically conceptualized based on the operation of the pipette 1 itself. For example, the step of aspirating the liquid stored in the container does not start when the user or the like brings the first end 11 of the capillary 10 into contact with the liquid stored in the container, but rather when the volume of the pressure chamber 21 increases. is assumed to be when the However, each step may be conceptualized including actions of the user or the like.

FIG. 6 is a list showing an overview of multiple steps (SA-SK). The "Symbol" column shows the symbols SA to SK of the steps in FIGS. The "step" column indicates the name of the step.

The "mode" column indicates whether the operation mode of each step is "automatic" or "manual". "Automatic" here means that the operation of each step is executed from the beginning to the end without waiting for the operation of the operation unit 25 after the start of each step, as described with reference to the timetable of FIG. means that On the other hand, "manually" means that a predetermined operation in each step is executed on the condition that the operation unit 25 is operated after the start of each step, for example.

The “start condition” column indicates whether each step is started by an operation on the operation unit 25 or automatically started without an operation by the operation unit 25 . In the figure, "automatically (time)" means, for example, that the process is automatically started when a predetermined time has elapsed after the step preceding the target step is completed. "Automatic (signal)" relates to a liquid suction device 101 (FIG. 9), which will be described later.

The aspects shown in "Style" and "Starting Conditions" in FIG. 6 are only examples. Therefore, for example, "automatic" in "style" may be replaced with "manual," and vice versa. Similarly, "automatic" in the "start condition" may be replaced with "manipulated", and vice versa.

As already mentioned, the operation of the actuator 50 and/or the valve 23 in each step is defined by the corresponding information (one of DA-DK). Steps and information that correspond to each other have the same names and AK codes. To confirm, the operation of the mounting step SA is defined by the mounting information DA. The operation of the pre-wash step SB is defined by the pre-wash information DB. The operation of the residual pressure release step SC is defined by the residual pressure release information DC. The operation of the pre-action step SD is defined by the pre-action information DD. The operation of the first suction step SE is defined by the first suction information DE. The operation of the second suction step SF is defined by the second suction information DF. The operation of the pull-up preparation step SG is defined by the pull-up preparation information DG. The operation of the pulling step SH is defined by the pulling information DH. The operation of the mixing step SI is defined by the mixing information DI. The operation of the measurement preparation step SJ is defined by the measurement preparation information DJ. The operation of the removal step SK is defined by removal information DK.

Each step will be described below with reference to FIGS.

(Time points t1 to t2: installation)
The attachment step SA is a step of attaching the capillary 10 to the pipette body 20 . Before this step (before time t1), the control unit 24 does not output, for example, drive signals to the drive unit 50 and the valve 23 (the signals are potentials Va0 and Vb0). When the preparation for attaching the capillary 10 to the pipette body 20 is completed, the user performs a predetermined operation on the operation section 25 (time t1). When determining that a predetermined signal has been input from the operation unit 25 , the control unit 24 generates a signal and outputs the generated signal to the valve 23 according to the mounting information DA. It should be noted that in the mounting step SA, the signal output to the drive unit 50 is stopped (the signal is set to the potential Va0).

The mounting information DA is, for example, incorporated into the program. The control unit 24 executing this program, for example, first starts outputting a signal (signal of potential Vb1) for opening the valve 23 (time t1). As a result, the inside of the pressure chamber 21 is opened to the atmosphere through the open channel 28 . As a result, for example, when the capillary 10 is attached to the pipette body 20, the probability that the pressure in the pressure chamber 21 fluctuates is reduced. As a result, the probability that an unintended load is applied to the pressure chamber 21 is reduced.

After that, when the attachment of the capillary 10 to the pipette body 20 is completed, the user performs a predetermined operation on the operation section 25 . The control unit 24 following the installation information DA stops outputting the signal for opening the valve 23 when it determines that a predetermined signal has been input from the operation unit 25 (time t2). The valve 23 is thereby closed.

(Time points t3 to t9: pre-wash)
The prewash step SB is a step of washing the inside of the capillary 10 with a prewash liquid. The pre-wash solution may be any suitable solution, for example a buffer solution. Examples of the buffer include TE obtained by adding EDTA (Ethylenediaminetetraacetic acid) to Tris buffer (tris(hydroxymethyl)aminomethane).

After the installation step SA (after the operation of closing the valve 23), the user brings the first end 11 of the capillary 10 into contact with the pre-washing liquid stored in a predetermined container (wetting the liquid). Then, the user performs a predetermined operation on the operation unit 25 (time t3). When determining that a predetermined signal is input from the operation unit 25 , the control unit 24 generates a signal and outputs the generated signal to the driving unit 50 and the valve 23 according to the prewash information DB.

The pre-wash information DB defines the following operations. After starting at time t3, the following series of operations are automatically performed as time elapses, as described with reference to FIG.

First, an operation for sucking the pre-washing liquid from the first end 11 is defined. Specifically, the operation of increasing the volume of the pressure chamber 21 with the valve 23 closed is defined. The waveform of the first drive signal SgA at this time is, for example, a waveform that increases from the potential Va0 to a predetermined potential Va1, then decreases to a predetermined potential Va2, and maintains the potential Va2. Note that FIG. 3 shows time points t3-0, t3-1 and t3-2 obtained by subdividing the time point t3 of FIG.

Basically, when the volume of the pressure chamber 21 increases, the liquid is sucked into the capillary 10, and when the volume of the pressure chamber 21 stops increasing, the suction of the liquid also stops. Therefore, unlike the illustrated example, the waveform for suction in the first drive signal SgA may be a waveform that realizes such a change in the volume of the pressure chamber 21 . That is, the waveform for suction may be a signal that rises from the potential before suction (here, Va0) to a predetermined potential and maintains the predetermined potential. In this case, the potential difference before and after suction is set according to the amount of suction.

As in the illustrated example, when the waveform for suction is a signal that rises to the potential Va1 and then drops to the potential Va2, for example, the accuracy of liquid measurement can be improved. Specifically, it is as follows.

If the volume of the pressure chamber 21 is simply increased to a certain size, a phenomenon may occur in which the liquid continues to be sucked even after the increase in volume is stopped. Such phenomena are due, for example, to inertial forces acting on the liquid. And it can be difficult to ignore such phenomena. For example, when a very small amount of liquid is to be sucked, variations in the amount of sucked caused by the phenomenon described above tend to become relatively large, making it difficult to suck the liquid with the intended precision.

Therefore, the decrease in the volume of the pressure chamber 21 (increase in the pressure in the capillary 10) accompanying the decrease from the potential Va1 to the potential Va2 causes a braking force against the inertial force to act on the liquid, and the probability that the phenomenon described above will occur. can be reduced. In such a waveform, for example, the potential difference between the potentials Va0 and Va1, the potential difference between the potentials Va1 and Va2, and the time (pulse width) from the potential Va0 to the potential Va2 via the potential Va1 are adjusted. Any amount of suction can be achieved.

In the example of FIG. 4, the pulse width is relatively short, and the waveform from the potential Va0 to the potential Va2 via the potential Va1 is depicted as an impulse. Note that the impulse waveforms (time points t3, t14, t15, and t19) drawn in FIGS. 4 and 5 may have an appropriate shape when expanded in the horizontal direction, such as a rectangular shape. It may be any of waves, triangular waves, sawtooth waves and sin waves (curved waves). In addition, although the pulse width of the waveform drawn in impulse form (the period from when the potential starts to rise to when the potential finishes falling) is relatively short, the drive unit 50 responds to changes in the potential. It has a time length that can be displaced accordingly.

Next, the pre-washing information DB defines an operation for preparing to discharge the pre-washing liquid from the first end 11 . Specifically, the operation is defined to open the valve 23 (time t4) and increase the volume of the pressure chamber 21 with the valve 23 open (time t5 to t6). At this time, the first drive signal SgA increases, for example, from potential Va2 to predetermined potential Va3 at a substantially constant rate of change.

Although the volume of the pressure chamber 21 increases, since the pressure chamber 21 is open to the atmosphere, the pressure of the pressure chamber 21 is maintained at the atmospheric pressure. As a result, the position of the prewash liquid in capillary 10 does not change. For example, the pre-wash liquid is maintained near the first end 11 . It should be noted that, unlike the illustrated example, such a preparation operation for ejection may be omitted.

Finally, the pre-washing information DB defines an operation for discharging the pre-washing liquid from the first end 11 . Specifically, an operation is defined in which the valve 23 is closed (time t7) and the volume of the pressure chamber 21 is decreased (time t8 to t9) with the valve 23 closed. At this time, the first drive signal SgA decreases, for example, from the potential Va3 to a predetermined potential Va0 at a substantially constant rate of change.

The pre-wash liquid in the capillary 10 is discharged from the first end 11 by reducing the volume of the pressure chamber 21 . At this time, the reduction amount (absolute value) of the volume of the pressure chamber 21 is large compared to the case where the volume is not increased because the volume was increased before the volume decrease started. From another point of view, the absolute value of the decrease in volume in ejection (see Va3-Va0) is greater than the increase in volume in suction (Va2-Va0 or Va1-Va0). As a result, for example, the probability of pre-washing liquid remaining in the capillary 10 is reduced.

For example, when the user determines that the pre-washing liquid has been discharged from the capillary 10 based on visual observation and/or the elapsed time, the user lifts the capillary 10 from the pre-washing liquid stored in a predetermined container (syneresis is performed). conduct.).

(Time points t10 to t11: Residual pressure release)
The residual pressure release step SC is a step for opening the valve 23 to make the pressure in the pressure chamber 21 equal to the atmosphere. The pressure chamber 21 is open to the atmosphere via the capillary 10 after the pre-wash liquid is discharged, but by opening the valve 23, the pressure in the pressure chamber 21 can be quickly made equal to the atmospheric pressure.

When the user pulls up the capillary 10 from the pre-washing liquid stored in a predetermined container, the user performs a predetermined operation on the operation section 25 (time t10). When determining that a predetermined signal has been input from the operation unit 25 , the control unit 24 generates a signal and outputs the generated signal to the valve 23 according to the residual pressure release information DC. In the residual pressure release step SC, the signal output to the driving section 50 is stopped (the signal is set to the potential Va0).

The residual pressure release information DC is stored, for example, in the form of a timetable. Therefore, the operation defined by the residual pressure release information DC is automatically performed as time elapses after the start. Specifically, first, an operation to open the valve 23 is performed (time t10). After a predetermined time has passed (time t11), the valve 23 is closed.

(Time points t12 to t13: pre-operation)
The pre-operation step SD is a step of making preparations for aspirating the liquid to be tested. This step may be started under the condition that the user performs a predetermined operation on the operation unit 25, or automatically under the condition that a predetermined time has elapsed after the residual pressure release step SC is completed. may be started. When determining that the start condition is satisfied (time t12), the control unit 24 generates a signal and outputs the generated signal to the driving unit 50 according to the pre-operation information DD. In this step, the signal output to the valve 23 is stopped (the signal is set to the potential Vb0) and the valve 23 is closed.

The pre-operation information DD is stored, for example, in the form of a timetable. Therefore, the action defined by the pre-action information DD is automatically performed as time elapses after the start. Specifically, the volume of the pressure chamber 21 is increased or decreased once or more. In the example of FIG. 4, the pressure chamber 21 is increased and decreased three times.

The waveform of the first drive signal SgA at this time may be set appropriately. For example, the waveform may be a square wave, a triangular wave, a sawtooth wave, and a sinusoidal wave (a curved wave; the example shown). In addition, the size of the increased volume (increased potential from another point of view) and decreased volume (from another point of view, decreased potential) may be set as appropriate. This size may be constant or may vary during repeated increases and decreases in volume. In the illustrated example, the potential changes repeatedly between the potential Va0 and the potential Va4. The repetition period may also be set appropriately. Note that the phrase “repeated increase and decrease” may refer to, for example, a case in which an increase and a decrease occur alternately two or more times. The same is true for other steps (eg SH and SI).

When the volume of the pressure chamber 21 is increased or decreased in this way, air is sucked into the capillary 10 from the first end 11 and discharged. This can reduce, for example, variations in humidity and/or temperature within the capillary 10 . As a result, for example, in sucking liquid to be described later, it is possible to reduce errors in the amount of liquid sucked due to variations in humidity and/or temperature.

(Time t14: first suction)
The first aspirating step SE is a step of aspirating the first liquid to be measured into the capillary 10 . When the user determines that the pre-operation step SD has been completed based on the elapsed time or the like, the user brings the first end 11 of the capillary 10 into contact with the first liquid stored in a predetermined container (performs liquid contact). Then, the user performs a predetermined operation on the operation unit 25 (time t14). When determining that a predetermined signal has been input from the operation unit 25 , the control unit 24 generates a signal and outputs the generated signal to the drive unit 50 according to the first suction information DE. In this step, the signal output to the valve 23 is stopped (the signal is set to the potential Vb0) and the valve 23 is closed.

The first suction information DE is stored, for example, in the form of a timetable. Therefore, the operation defined by the first suction information DE is automatically performed as time elapses after the start. Specifically, the volume of the pressure chamber 21 is increased while the valve 23 is closed. As a result, the first liquid is sucked into the capillary 10 from the first end 11 .

The waveform of the first drive signal SgA at this time is, for example, similar to the waveform (time t3) when the pre-washing liquid is sucked in the pre-washing step SB. That is, the waveform in the first suction step SE is a signal that rises from the potential Va0 to a predetermined potential Va5, then drops to a predetermined potential Va6, and maintains the potential Va6. The action of such a waveform is as described in the explanation of the prewash step SB.

The suction amount of the first liquid is, for example, similar to the suction amount of the pre-washing liquid, the potential difference between the potentials Va0 and Va5, the potential difference between the potentials Va5 and Va6, and the potential difference from the potential Va0 to the potential Va6 via the potential Va5. It is defined by adjusting the time (pulse width) to In the illustrated example, the pulse width is relatively short, and the waveform from the potential Va0 to the potential Va6 via the potential Va5 is depicted as an impulse. Note that the waveform in the first suction step SE may rise from the potential Va0 to a predetermined potential and maintain the predetermined potential, unlike the illustrated example.

When the user determines that the first liquid has been sucked into the capillary 10 visually and/or with the passage of time, the user pulls up the capillary 10 from the first liquid stored in the container (performs syneresis). Since the space (pressure chamber 21, etc.) on the second end 12 side from the first liquid is sealed, the first liquid sucked into the capillary 10 is maintained in a state of being positioned near the first end 11. .

(Time t15: second suction)
The second aspirating step SF is a step of aspirating the second liquid to be measured into the capillary 10 . When the user pulls up the capillary 10 from the first liquid stored in a predetermined container, the first end 11 of the capillary 10 is brought into contact with the second liquid stored in another container. Then, the user performs a predetermined operation on the operation unit 25 (time t15). When determining that a predetermined signal has been input from the operation unit 25 , the control unit 24 generates a signal and outputs the generated signal to the driving unit 50 according to the second suction information DF. In this step, the signal output to the valve 23 is stopped (the signal is set to the potential Vb0) and the valve 23 is closed.

The second suction information DF is stored, for example, in the form of a timetable. Therefore, the operation defined by the second suction information DF is automatically performed as time elapses after the start. Specifically, the volume of the pressure chamber 21 is increased while the valve 23 is closed. As a result, the second liquid is sucked into the capillary 10 from the first end 11 following the first liquid that has already been sucked near the first end 11 .

At this time, the waveform of the first drive signal SgA increases from the potential Va6 at the end of the first suction step SE to a predetermined potential Va7, then decreases to a predetermined potential Va8, and maintains the potential Va8. is a signal. The action of such a waveform is as described in the explanation of the prewash step SB.

The suction amount of the second liquid, for example, similarly to the suction amount of the pre-washing liquid, is the potential difference between the potentials Va6 and Va7, the potential difference between the potentials Va7 and Va8, and the potential difference from the potential Va6 to the potential Va8 via the potential Va7. It is defined by adjusting the time (pulse width) to In the illustrated example, the pulse width is relatively short, and the waveform from the potential Va6 to the potential Va8 via the potential Va7 is depicted as an impulse. Note that the waveform in the second suction step SF may increase from the potential Va6 to a predetermined potential and maintain the predetermined potential, unlike the illustrated example.

When the user determines that the second liquid has been sucked into the capillary 10 visually and/or with the passage of time, the user pulls the capillary 10 out of the second liquid stored in the container. Since the space (pressure chamber 21, etc.) on the second end 12 side from the first liquid and the second liquid is sealed, the first liquid and the second liquid sucked into the capillary 10 are in the vicinity of the first end 11. position is maintained.

(Time points t16 to t18: Preparing for lifting)
The pull-up preparation step SG is a step of preparing to move the first liquid and the second liquid from the first end 11 side to the second end 12 side within the capillary 10 . After pulling up the capillary 10 from the second liquid stored in the container, the user performs a predetermined operation on the operation unit 25 (time t16). When determining that a predetermined signal has been input from the operation unit 25 , the control unit 24 generates a signal and outputs the generated signal to the driving unit 50 and the valve 23 according to the pull-up preparation information DG.

The pull-out preparation information DG is stored, for example, in the form of a timetable. Therefore, the operation specified by the pull-up preparation information DG is automatically carried out as time elapses after the start. Specifically, the operations performed here are, for example, as follows.

First, valve 23 is opened (time t16). With the valve 23 open, the volume of the pressure chamber 21 is reduced (time t17). Since the pressure chamber 21 is open to the atmosphere through the valve 23, even if the volume of the pressure chamber 21 decreases, the pressure in the pressure chamber 21 does not increase, and the pressure in the pressure chamber 21 is maintained at the atmospheric pressure. be. As a result, the first liquid and the second liquid are not discharged from the first end 11, and the current position is maintained. After that, the valve 23 is closed (time t18). With this operation, when the volume of the pressure chamber 21 is increased to draw up the first liquid and the second liquid, the amount of increase can be increased. The volume of the pressure chamber 21 after reduction at time t17 (the potential after the first drive signal SgA has dropped) may be set to an appropriate size. In the example of FIG. 4, the potential of the first drive signal SgA is Va0.

(Time points t19 to t21: pulling up)
The pulling step SH is a step of moving the first liquid and the second liquid in the capillary 10 from the first end 11 side to the second end 12 side. As a result, for example, the first liquid and the second liquid move within the capillary 10 to positions convenient for subsequent steps. The lifting step SH may be started under the condition that the user has performed a predetermined operation on the operation unit 25, or may be automatically started under the condition that a predetermined time has elapsed after the completion of the lifting preparation step SG. may be started. When determining that the start condition is satisfied (time t19), the control unit 24 generates a signal and outputs the generated signal to the driving unit 50 according to the lifting information DH. In this step, the signal output to the valve 23 is stopped (the signal is set to the potential Vb0) and the valve 23 is closed.

The withdrawal information DH is stored, for example, in the form of a timetable. Therefore, the operation specified by the lifting information DH is automatically performed as time elapses after the start. Specifically, the defined operations are, for example, as follows.

First, the lifting information DH defines an operation of moving the first liquid and the second liquid from the first end 11 side to the second end 12 side at a relatively high speed (time t19). Specifically, for example, with the valve 23 closed, the volume of the pressure chamber 21 is increased and then decreased. The waveform of the first drive signal SgA at this time is, for example, such that the potential rises to the potential Va9 in a relatively short time (pulse width), and then the potential falls. That is, the waveform is pulse-shaped (furthermore, impulse-shaped).

The above waveform has the same effect as the waveform at time t3 of prewash step SB. That is, due to the increase in the volume of the pressure chamber 21, the pressure on the second end 12 side is reduced below that of the liquid in the capillary 10, and the liquid flows toward the second end 12 side. Due to the subsequent decrease in the volume of the pressure chamber 21, the pressure on the second end 12 side is increased more than the liquid in the capillary 10, and a braking force acts on the liquid against the inertial force acting on the liquid toward the second end 12 side. . The action of the braking force improves the accuracy of the stop position of the liquid.

At time t3, the potential Va2 after the drop is higher than the potential Va0 before the rise. On the other hand, at time t19, the potential after falling is equal to the potential Va0 before rising. At the time t19, unlike the time t3, the first end 11 is not in contact with the liquid, and the liquid is at the second end 12 with respect to the increase in potential compared to the case where the first end 11 is in contact with the liquid. This is because it is easy to move to However, even at time t19, the potential after the drop may be higher than the potential Va0.

The amount of movement of the first liquid and the second liquid can be defined, for example, by adjusting the potential difference between the potentials Va0 and Va9, the time (pulse width) from the potential Va0 to the potential Va0 via the potential Va9, and the like. . Note that the waveform at time t19 may rise from the potential Va0 to a predetermined potential and maintain the predetermined potential, unlike the illustrated example.

Next, the lifting information DH defines an operation of moving the first liquid and the second liquid from the first end 11 side to the second end 12 side at a relatively slow speed (time points t20 to t21). Specifically, an operation of repeatedly increasing and decreasing the volume of the pressure chamber 21 with the valve 23 closed is defined.

The waveform of the first drive signal SgA at this time may be set appropriately. For example, the waveform may be a square wave, a triangular wave, a sawtooth wave, and a sinusoidal wave (a curved wave; the example shown). In addition, the size of the increased volume (increased potential from another point of view) and decreased volume (from another point of view, decreased potential) may be set as appropriate. This size may be constant or may vary during repeated increases and decreases in volume. In the illustrated example, the potential repeatedly fluctuates between the potential Vb10 and the potential Vb11 except at the start (time t20) and the end (time t21). The repetition period may also be set appropriately.

When the volume of the pressure chamber 21 is repeatedly increased and decreased in this way, the liquid gradually moves from the first end 11 side to the second end 12 side and then moves to the opposite side while repeating the movement to the second end 12 side. move to the side. Normally, even if the volume of the pressure chamber 21 is repeatedly increased and decreased, the liquid vibrates within the same range and does not move. However, by satisfying appropriate conditions, the liquid moves from the first end 11 side to the second end 12 side as the volume of the pressure chamber 21 increases or decreases.

For example, as shown in FIG. 1, the hole 10a of the tip member 14 is tapered such that the diameter becomes smaller toward the first end 11 side. The flow path resistance when the liquid located in this hole 10 a flows toward the first end 11 is greater than the flow path resistance when the liquid flows toward the second end 12 . Consequently, the amount of movement of the liquid toward the first end 11 side is smaller than the amount of movement of the liquid toward the second end 12 side. As a result, the liquid gradually moves toward the second end 12 while repeatedly vibrating.

Further, for example, the hole 10b of the glass tube 13 has a smaller diameter and a more hydrophilic inner surface than the hole 10a of the tip member 14 . Therefore, when positioned at the boundary between the holes 10b and 10a, a capillary force is generated that causes the liquid to flow from the first end 11 side to the second end 12 side. As a result, the liquid gradually moves toward the second end 12 while repeatedly vibrating.

(Time points t22 to t23: mixing)
The mixing step SI is a step of mixing the first liquid and the second liquid within the capillary 10 . The mixing step SI may be started under the condition that the user performs a predetermined operation on the operation unit 25, or it is automatically started under the condition that a predetermined time has elapsed after the completion of the lifting step SH. may be When determining that the start condition is satisfied (time t22), the control unit 24 generates a signal and outputs the generated signal to the driving unit 50 according to the information for mixing DI. In this step, the signal output to the valve 23 is stopped (the signal is set to the potential Vb0) and the valve 23 is closed.

The mixing information DI is stored, for example, in the form of a timetable. Therefore, the operation defined by the mixing information DI is automatically performed as time elapses after the start. Specifically, the increase and decrease in the volume of the pressure chamber 21 are repeated an appropriate number of times (four times in the illustrated example). As a result, the first liquid and the second liquid alternately repeat moving toward the second end 12 and moving toward the first end 11 . As a result, both liquids are stirred, and the mixing of both liquids proceeds.

The waveform of the first drive signal SgA at this time may be set appropriately. For example, the waveform may be a square wave, a triangular wave, a sawtooth wave, and a sinusoidal wave (a curved wave; the example shown). In addition, the size of the increased volume (increased potential from another point of view) and decreased volume (from another point of view, decreased potential) may be set as appropriate. This size may be constant or may vary during repeated increases and decreases in volume. In the illustrated example, the potential repeatedly fluctuates between the potential Vb13 and the potential Vb14 except at the start (time t22) and the end (time t23). The repetition period may also be set appropriately.

(Time points t24 to t27: preparation for measurement)
The measurement preparation step SJ is a step of making preparations for measuring properties and/or components of the mixed liquid. This step may be started under the condition that the user performs a predetermined operation on the operation unit 25, or it is automatically started under the condition that a predetermined time has passed since the mixing step SI was completed. may When determining that the start condition is satisfied (time t24), the control unit 24 generates a signal and outputs the generated signal to the driving unit 50 and the valve 23 according to the measurement preparation information DJ.

The measurement preparation information DJ is stored, for example, in the form of a timetable. Therefore, the operation defined in the measurement preparation information DJ is automatically performed as time passes after the start. The specified operation is, for example, the same as the operation specified in the pull-out preparation information DG. Specifically, it is as follows.

First, valve 23 is opened (time t24). With the valve 23 open, the volume of the pressure chamber 21 is reduced (time points t25 to t26). Since the pressure chamber 21 is open to the atmosphere through the valve 23, even if the volume of the pressure chamber 21 decreases, the pressure in the pressure chamber 21 does not increase, and the pressure in the pressure chamber 21 is maintained at the atmospheric pressure. be. The liquid in the capillary 10 is thus maintained at its current position. After that, the valve 23 is closed (time t27).

In the first drive signal SgA, the potential after the volume reduction of the pressure chamber 21 is completed is, for example, the reference potential Va0. That is, the output of the signal to the driving section 50 is stopped. Therefore, for example, power consumption can be reduced by stopping the driving of the driving unit 50 while maintaining the position of the liquid.

(Time points t27 to t28: measurement)
The measuring step (not labeled) is a step of measuring properties and/or components of the liquid (mixture of the first liquid and the second liquid) in the capillary 10 . This measurement is performed, for example, by irradiating the liquid in the capillary 10 (for example, the glass tube 13) with light. Such measurements can include, for example, fluorescence measurements, scattering measurements, absorption measurements, and spectroscopy measurements. During this measurement, the potentials of the first drive signal SgA and the second drive signal SgB are, for example, potentials Va0 and Vb0. That is, no signal is output.

(Time t28-t29: Removal)
The removing step SK is a step of removing the capillary 10 from the pipette body 20 . After completing the measurement of the liquid in the capillary 10, the user performs a predetermined operation on the operation unit 25 (time t28). When the controller 24 determines that a predetermined signal has been input from the operation unit 25 (time t28), the controller 24 executes the removal step SK according to the removal information DK.

The removal information DK may be similar to the attachment information DA. Therefore, the control unit 24 following the removal information DK, for example, first starts outputting a signal (signal of potential Vb1) for opening the valve 23 (time t28). As a result, the inside of the pressure chamber 21 is opened to the atmosphere through the open channel 28 . As a result, for example, when the capillary 10 is removed from the pipette body 20, the probability that the pressure in the pressure chamber 21 fluctuates is reduced. As a result, the probability that an unintended load is applied to the pressure chamber 21 is reduced.

After that, when the removal of the capillary 10 from the pipette main body 20 is completed, the user performs a predetermined operation on the operation section 25 . The control unit 24 following the removal information DK stops outputting the signal for opening the valve 23 when it determines that a predetermined signal has been input from the operation unit 25 (time t29). The valve 23 is thereby closed. Note that the removal step SK may be omitted and the capillary 10 may be removed in the following attachment step SA. That is, the capillary 10 may be exchanged.

(Suction volume in pre-wash)
7(a) to 7(d) are schematic cross-sectional views for explaining pre-washing. For the purposes of this discussion, pre-washing includes wettability and syneresis.

FIG. 7( a ) shows a liquid contacting step of bringing the first end 11 of the capillary 10 into contact with the pre-washing liquid LW stored in the container 151 . FIG. 7(b) shows a state in which the first end 11 is in contact with the pre-washing liquid LW after the liquid contacting step, and the drive unit 50 is controlled to increase the volume of the pressure chamber 21 for pre-washing. A suction step for sucking the liquid LW into the capillary 10 is shown (time points t3 to t4). FIG. 7(c) shows that after the suction step, the first end 11 is in contact with the pre-washing liquid LW, and the drive unit 50 is controlled to reduce the volume of the pressure chamber 21, thereby pre-washing the liquid. A discharge step for discharging LW from the capillary 10 is shown (time points t4 to t9). FIG. 7(d) shows a syneresis step in which the capillary 10 is pulled up from the pre-washing liquid LW stored in the container 151 after the discharge step.

Here, in the suction step (FIG. 7(b)), the suction amount of the pre-washing liquid LW is, for example, only through the hole 10a of the hole 10b of the glass tube 13 and the hole 10a of the tip member 14. may be such that . At this time, the pre-wash liquid LW may not reach the boundary between the holes 10a and 10b as in the illustrated example, or may reach the boundary unlike the illustrated example. (It may be in contact with the step surface between the hole 10a and the hole 10b.). As already described, the holes 10a are, for example, more water-repellent than the holes 10b, and thus the pre-washing liquid is less likely to adhere (be less likely to remain) after ejection. Note that unlike the illustrated example, the pre-wash liquid may be sucked up to the hole 10b.

(Rate of change in pre-wash)
FIG. 8 is a diagram showing a part of FIG. 4 (pre-washing step SB: time points t3 to t9) enlarged along the horizontal axis.

As described above, in the pre-wash step SB, after the pre-wash liquid is sucked, the volume of the pressure chamber 21 is increased (time t5-t6) while the valve 23 is open (time t4-). After that, the volume of the pressure chamber 21 is reduced (from time t8 to t9) while the valve 23 is closed (from time t7). In this series of operations, the absolute value of the potential change rate ((Va3−Va2)/(t6−t5)) when increasing the volume of the pressure chamber 21 is the potential change rate when decreasing the volume of the pressure chamber 21. It may be smaller than the absolute value of the rate of change ((Va0-Va3)/(t9-t8))). Note that, unlike the illustrated example, the former may be greater than or equal to the latter.

In the illustrated example, the rate of change in potential when increasing the volume of the pressure chamber 21 is constant over the period of increase (time points t5 to t6) and is the same as the slope of the straight line representing the first drive signal SgA. be. Similarly, the potential change rate when the volume of the pressure chamber 21 is decreased is constant over the period of decrease (time points t8 to t9) and is the same as the slope of the straight line representing the first drive signal SgA. If the rate of change in potential when increasing or decreasing the volume of the pressure chamber 21 is not constant over the period of increase or decrease, the average rate of change in each period may be used for comparison.

[Examples of pipette applications]
In the above description, basically, the user operates the pipette 1 as an example. However, as already mentioned, the pipette 1 may be operated by a device that replaces the user. An example is shown below.

FIG. 9 is a schematic perspective view showing the appearance of a liquid suction device 101 including the pipette 1. FIG. For convenience, the pipettes are given the same reference numerals as in the previous description, but as will be understood from the description below, the pipettes may be appropriately modified for incorporation into the liquid suction device 101.

The liquid suction device 101 includes, for example, a pipette 1 (pipette structure 15), a moving mechanism 103 that holds the pipette 1, a control unit 105 that controls these, and a control unit 105 that receives a signal according to a user's operation. and an operation unit 119 for outputting to.

The moving mechanism 103 relatively moves the pipette 1 and the container 107 in which the liquid is stored on behalf of the user. That is, the moving mechanism 103 can bring the capillary 10 into contact with and separate from the liquid stored in the container 107 .

The configuration of the moving mechanism 103 may be made as appropriate. In the illustrated example, the moving mechanism 103 includes a holding portion 109 that holds the pipette body 20, a movable portion 111 to which the holding portion 109 is fixed, and a column 113 that holds the movable portion 111 so as to be vertically movable. have. The column 113 incorporates, for example, a linear motor (not shown), and drives the movable section 111 up and down based on a signal from the control section 105 . A container 107 is arranged below the pipette 1 . Wetting is performed by driving the pipette 1 downward. Syneresis is performed by driving the pipette 1 upward. Unlike the illustrated example, the moving mechanism may be configured to perform liquid contact and liquid separation by driving the container 107 up and down.

The pipette body 20 is, for example, detachable from the moving mechanism 103 (holding section 109). The attaching/detaching method may be appropriate. For example, threading, engagement, press fitting and/or clamping may be used. Here, the movement mechanism 103 and the pipette main body 20 are explained as being separate. However, the pipette body 20 may be designed on the assumption that it will be incorporated into the liquid suction device 101 from the beginning, and may be configured so as not to be detachable from the movement mechanism 103 . From another point of view, the boundary between the pipette body 20 and the moving mechanism 103 may not necessarily be clear.

A camera 115 is also fixed to the movable portion 111 . The camera 115 captures an image of the capillary 10 and outputs data of the captured image to the control unit 105, for example. The control unit 105 can determine, for example, whether the error in the amount of suction is within the allowable range based on the input image.

The container 107 has, for example, a plurality of (four in the illustrated example) recesses 107a arranged on a circumference around a predetermined center line CL. The multiple recesses 107a are open in a direction (upward) along the center line CL. Different types of liquids (pre-washing liquid, first liquid, and second liquid) to be sucked into the pipette 1 are individually stored in the plurality of recesses 107a.

The moving mechanism 103 has a stage 117 that holds the container 107 . The stage 117 holds the container 107 so that the center line CL is eccentric from the capillary 10 and substantially parallel to the capillary 10 . Further, the stage 117 incorporates a motor, for example, and can rotate the container 107 around the center line CL based on a signal from the control section 105 . By rotating the container 107 by the stage 117, the concave portion 107a positioned below the pipette 1 is replaced. As a result, the wetted liquid is changed when the pipette 1 is moved downward.

Like the control unit 24, the control unit 105 includes, for example, a CPU, a ROM, a RAM, and an external storage device (not shown). Various functional units that perform various operations are constructed by the CPU executing programs stored in the memory. The control unit 105 may be fixedly provided on the moving mechanism 103 (a fixed part thereof), or may be provided partially or wholly so as to be relatively movable with respect to the moving mechanism 103 .

The control unit 105 and the control unit 24 may be separated in terms of hardware, or may be partially or wholly integrated. In the former case, for example, an IC or the like that constitutes the control section 24 is provided in the pipette body 20, an IC or the like that constitutes the control section 105 is provided outside the pipette body 20, and the two are electrically connected by a cable or the like. It's okay. Also, in the latter case, for example, an IC or the like constituting the control section 105 and the control section 24 may be provided outside the pipette body 20 and connected to the driving section 50 and the valve 23 by cables or the like.

In any of the above cases, the control section 105 and the control section 24 may be conceptualized as the control section 106 that the liquid suction device 101 has. Even when the control unit 105 and the control unit 24 are integrated in terms of hardware, the control unit 105 may output a signal to the control unit 24 for convenience in the description of the present disclosure.

The configuration of the operation unit 119 may be made as appropriate, and for example, the above description of the configuration of the operation unit 25 may be used by replacing the pipette body 20 with the movement mechanism 103 . The operation unit 119 may accept any operation described as an operation accepted by the operation unit 25 instead of the operation unit 25 . The pipette 1 used in the liquid suction device 101 may or may not have the operation portion 25 .

The liquid suction device 101 may perform, for example, any one of the various steps described above. For example, the liquid suction device 101 may execute all steps or may execute some steps. For example, the liquid suction device 101 may perform from the prewash step SB to the measurement preparation step SJ.

In the column of "start condition" in FIG. It shows that a signal to unit 24 can trigger a step start. Therefore, for example, after starting the pre-washing step SB, the pre-washing step SJ may be automatically performed without waiting for the operation of the operation unit 25 (and 119) until the completion of the measurement preparation step SJ. The initiation of the pre-wash step SB may also occur automatically after completion of any steps.

FIG. 10 is a flow chart showing the main part of an example of the procedure of processing executed by the liquid suction device 101 . The flow on the left side of the figure shows processing executed by the control unit 105 on behalf of the user (operation unit 25). The flow on the right side of the figure shows the processing executed by the control unit 24 . The processing executed by the control unit 24 is also executed when the user operates the pipette 1 .

Here, attention is focused on the pre-wash step SB and the first suction step SE. Illustrations of other steps are basically omitted. Also, in the following description, for the sake of convenience, a mode in which the residual pressure release step SC and the pre-operation step SD are not performed will be described.

Before step ST1, below the pipette 1 held by the moving mechanism 103, the recess 107a in which the pre-washing liquid is stored is positioned. Then, in step ST1, the control section 105 drives the motor of the column 113 to lower the pipette 1 to a predetermined position. This causes the first end 11 of the capillary 10 to move into the recess 107a. As a result, the first end 11 contacts the pre-wash liquid. When the descent of the pipette 1 is completed, the control section 105 outputs a signal to the control section 24 informing it.

In step ST11, the control section 24 determines whether or not a signal notifying completion of lowering of the pipette 1 has been input from the control section 105 or not. If the determination is negative, the control unit 24 repeats (stands by) step ST11, and if the determination is positive, the process proceeds to step ST12.

At step ST12, the control unit 24 controls the driving unit 50 and the valve 23 according to the prewash information DB, as described with reference to FIGS. Then, when the operation specified in the pre-wash information DB is completed, the control unit 24 outputs a signal notifying the completion to the control unit 105 .

In step ST2, the control section 105 determines whether or not a signal notifying completion of the operation defined in the pre-washing information DB has been input from the control section 24 or not. If the determination is negative, the control section 105 repeats (stands by) step ST2, and if the determination is positive, the process proceeds to step ST3.

At step ST3, the control unit 105 drives the motor of the column 113 to raise the pipette 1 to a predetermined position. As a result, the first end 11 of the capillary 10 is pulled up from the pre-washing liquid stored in the recess 107a, and further moves out of the recess 107a.

At step ST4, the controller 105 drives the motor of the stage 117 to rotate the container 107 by a predetermined angle. As a result, the recess 107a in which the first liquid is stored is positioned below the pipette 1. As shown in FIG.

Step ST5 is basically the same as step ST1. That is, the control unit 105 drives the motor of the column 113 to lower the pipette 1 to a predetermined position. This causes the first end 11 of the capillary 10 to come into contact with the first liquid stored in the recess 107a. When the descent of the pipette 1 is completed, the control section 105 outputs a signal to the control section 24 informing it.

Step ST13 is basically the same as step ST11. That is, the control unit 24 determines whether or not a signal notifying completion of lowering of the pipette 1 has been input from the control unit 105 . If the determination is negative, the control unit 24 repeats (stands by) step ST13, and if the determination is positive, the process proceeds to step ST14.

In step ST14, the control section 24 controls the driving section 50 and the valve 23 according to the first suction information DE, as described with reference to FIGS. Then, when the operation specified in the first suction information DE is completed, the control unit 24 outputs a signal notifying the completion to the control unit 105 .

In step ST6, the control section 105 determines whether or not a signal notifying completion of the operation defined in the first suction information DE is input from the control section 24 or not. If the determination is negative, the control section 105 repeats (stands by) step ST6, and if the determination is positive, the control section 105 proceeds to the next step (not shown).

As can be inferred from the description so far, the second liquid is sucked by executing the processes basically similar to steps ST3 to ST5 and steps ST13 and ST14. Furthermore, the capillary 10 is pulled up from the second liquid by executing a process basically similar to that of step ST3.

When the pipette 1 is incorporated in the liquid aspirator 101 in this way, the user's operation on the operation unit 25 is triggered, as indicated by "auto (signal)" in the "start condition" column of FIG. The step that was supposed to be can also be started automatically. As a result, for example, operations on the operation unit 25 are reduced or eliminated, and the burden on the user is reduced. In addition, when the pipette 1 is relatively small, when the user performs liquid contact and liquid separation, variations in the position and speed of the pipette 1 during liquid contact and liquid separation have a relatively large effect on the suction amount. From this point of view as well, the burden on the user is reduced. From another point of view, the accuracy of the suction amount can be improved. Furthermore, when the user holds the pipette 1 , the user's body temperature affects the humidity and/or temperature inside the pipette 1 . By using the liquid suction device 101, such an influence can be reduced, and the precision of the suction amount can be improved.

As described above, according to the present embodiment, the pipette 1 has the capillary 10 , the pressure chamber 21 , and the drive section 50 in the prewash method for cleaning the capillary 10 of the pipette 1 . The capillary 10 is open at a first end 11 and a second end 12, which are both longitudinal ends. The pressure chamber 21 communicates with the inside of the capillary 10 via the second end 12 . The drive unit 50 changes the volume of the pressure chamber 21 . The pre-washing method includes a liquid contact step (FIG. 7(a)), a suction step (FIG. 7(b)), a discharge step (FIG. 7(c)), and a liquid separation step (FIG. 7(d). ). In the liquid contacting step, the first end 11 is brought into contact with the pre-washing liquid LW stored in the container 151 (or 107). In the suction step, after the liquid contacting step, while the first end 11 is in contact with the pre-washing liquid LW, the drive unit 50 is controlled to increase the volume of the pressure chamber 21 to draw out the pre-washing liquid LW. Suction into capillary 10 . In the discharging step, after the suction step, the drive unit 50 is controlled to reduce the volume of the pressure chamber 21 while the first end 11 is in contact with the pre-washing liquid LW, thereby discharging the pre-washing liquid LW into the capillary. Dispense from 10. In the syneresis step, after the discharging step, the capillary 10 is pulled up from the pre-washing liquid LW stored in the container 151 .

Therefore, for example, the pre-wash liquid in the capillary 10 is expelled due to the reduction in the volume of the pressure chamber 21 . As a comparative example, for example, there is a method of discharging the liquid in the capillary 10 by pressing a waste cloth against the first end 11 and soaking the pre-washing liquid into the waste cloth. Compared to such a comparative example, for example, the load applied to the first end 11 can be easily reduced, so the possibility of deformation of the capillary 10 is reduced. Also, for example, compared to the above comparative example, it is easier to reduce the probability of insufficient discharge of the pre-wash liquid. By reducing the probability of deformation of the capillary 10 and insufficient discharge of the pre-washing liquid, for example, the precision of the amount of liquid to be aspirated after that can be improved.

Further, for example, in the present embodiment, the pre-washing liquid is discharged while the first end 11 is in contact with the pre-washing liquid. As a comparative example, for example, there is a method in which the pre-wash liquid is discharged after the first end 11 is pulled up from the pre-wash liquid in the container 151 (or 107). Compared to such a comparative example, for example, the probability of the pre-washing liquid adhering (remaining) to the first end 11 can be reduced. Specifically, for example, in the comparative example, the pre-washing liquid may flow from the opening of the first end 11 to the outer surface of the first end 11 and its surrounding outer surface and adhere (do not drop). On the other hand, in the present embodiment, when the first end 11 is pulled up from the prewash liquid in the container, the prewash liquid in the container draws the prewash liquid around the first end 11 . As a result, adhesion of the pre-wash liquid is reduced. This effect tends to occur when the diameter of the capillary 10 is relatively small.

From another point of view, in this embodiment, the liquid suction device 101 has a pipette structure section 15, a moving mechanism 103, and a control section . The moving mechanism 103 relatively moves the pipette structure 15 and the container 107 that stores the liquid to be sucked into the pipette structure 15 . A control unit 106 controls the pipette structure unit 15 and the moving mechanism 103 . The pipette structure 15 has a capillary 10 , a pressure chamber 21 and a drive section 50 . The capillary 10 is open at a first end 11 and a second end 12, which are both longitudinal ends. The pressure chamber 21 communicates with the inside of the capillary 10 via the second end 12 . The drive unit 50 changes the volume of the pressure chamber 21 . The control unit 106 controls the moving mechanism 103 and the driving unit 50 so that the following operations are performed in order. First, the first end 11 is moved into the container 107 (Fig. 7(a)). After that, with the first end 11 positioned in the container 107, the volume of the pressure chamber 21 is increased by the first increase amount (see potential Va2-Va0 or potential Va3-Va0) (FIG. 7B). : time points t3 to t4). After that, the volume of the pressure chamber 21 is decreased by a first decrease amount (see potential Va0-Va3) having an absolute value equal to or larger than the first increase amount (FIG. 7(c): time t8 to t9). After that, the first end 11 is moved out of the container (Fig. 7(d)).

In this case, for example, while the first end 11 is positioned inside the container, the liquid is sucked and discharged at a discharge amount equal to or greater than the suction amount. Thus, for example, by placing a pre-wash liquid in a container, the pre-wash method described above can be achieved. In addition, as already described, the user's burden can be reduced and the influence of the user's body temperature on the humidity and/or temperature in the capillary 10 can be reduced compared to the case where the user operates.

From yet another viewpoint, the pipette 1 has a capillary 10, a pressure chamber 21, a driving section 50, and a control section 24 in this embodiment. The capillary 10 is open at a first end 11 and a second end 12, which are both longitudinal ends. The pressure chamber 21 communicates with the inside of the capillary 10 via the second end 12 . The drive unit 50 changes the volume of the pressure chamber 21 . The control section 24 controls the drive section 50 . Further, the control unit 24 stores a timetable (pre-washing information DB) that defines the operation of the drive unit 50, and controls the drive unit 50 according to the timetable. The pre-wash information DB increases the volume of the pressure chamber 21 by a first increase amount (see potential Va2-Va0 or potential Va3-Va0) and then increases a first decrease amount having an absolute value equal to or greater than the first increase amount. (refer to potential Va0-Va3), the operation (time points t3 to t9) is defined.

Therefore, for example, the pre-washing liquid is automatically sucked and discharged without waiting for the user's operation, thereby reducing the burden on the user. Moreover, such control can be used for a pre-washing method in which the liquid is discharged while it is in contact with the liquid. Now, let us consider a case where the user pulls up the first end 11 from the prewashing liquid in the container and then discharges the prewashing liquid in the capillary 10 as in the comparative example described above. As for the control of the control unit 24 in this case, after the first end 11 is pulled up from the pre-washing liquid in the container, the volume of the pressure chamber 21 starts to decrease with a predetermined operation of the operation unit 25 by the user as a trigger. can be considered. In other words, in a mode in which the control unit 24 automatically performs suction and discharge according to a timetable as in the present embodiment, in order to realize the pre-washing of the comparative example, the user must Either the pipette must be lifted or the period between the completion of the volume increase and the start of the volume decrease must be increased. Therefore, the control of the pipette 1 in this embodiment has little relevance to the prewash method of the comparative example.

In the present embodiment, the volume of the pressure chamber 21 is increased from the initial volume (see potential Va0) to the first volume (see potential Va1) in the pre-wash suction step (FIG. 7(b): time t3 to t4). and decrease from the first volume to a second volume (see potential Va2) larger than the initial volume, and control the drive unit 50 to maintain the second volume.

In this case, for example, as described above, a braking force can be applied to the pre-wash liquid to improve the accuracy of the suction amount. As a result, for example, variations in humidity and/or temperature within the capillary 10 after prewashing can be reduced. As a result, variations in the suction amount of the first liquid (liquid to be measured) caused by variations in humidity and/or temperature can be reduced. Further, since the accuracy of the suction amount is improved, for example, when the pre-washing liquid is suctioned only through the hole 10a of the hole 10b of the glass tube 13 and the hole 10a of the tip member 14, the gap between the hole 10a and the hole 10b is reduced. Aspiration of the pre-wash liquid to near the boundary is facilitated.

Further, in this embodiment, the pipette 1 has an openable/closable valve 23 that connects the pressure chamber 21 and the outside. In the pre-wash suction step (FIG. 7(b): time t3 to t4), the volume of the pressure chamber 21 is increased by the first increment (see potential Va2-Va0 or potential Va1-Va0) with the valve 23 closed. , the pre-washing liquid is sucked into the capillary 10 by controlling the drive unit 50 so as to increase the In the pre-wash discharge step (FIG. 7(c): time t4 to t9), the valve 23 is opened (time t4), and the volume of the pressure chamber 21 is increased by the second increase (potential Va3-Va2 ), the drive unit 50 is controlled to increase the After that, the valve 23 is closed (time t7), and with the valve 23 closed, the volume of the pressure chamber 21 is decreased by a first decrease amount (see potential Va0-Va3) whose absolute value is larger than the first increase amount. Then, the drive unit 50 is controlled to discharge the pre-washing liquid from the capillary 10 .

In this case, for example, the absolute value of the amount of decrease in the volume of the pressure chamber 21 when discharging the pre-washing liquid is sufficiently large relative to the amount of increase in the volume of the pressure chamber 21 when the pre-washing liquid is sucked. , so that the pre-washing liquid can be reliably discharged. As a result, for example, the influence of the remaining pre-wash liquid on the suction amount of the first liquid (liquid to be measured) is reduced.

In addition, in this embodiment, the drive unit 50 has a configuration that changes the volume of the pressure chamber 21 to a volume corresponding to the applied voltage. In pre-washing, the absolute value of the rate of change in the voltage applied to the drive unit 50 when increasing the volume of the pressure chamber 21 by the second increase amount ((Va3-Va2)/(t6-t5)) is the pressure chamber 21 is smaller than the absolute value of the change rate ((Va0−Va3)/(t9−t8))) of the voltage applied to the drive unit 50 when the volume of the sensor 21 is decreased by the first decrease amount.

Here, the valve 23 is closed during the period (time points t8 to t9) in which the volume of the pressure chamber 21 is decreased. Therefore, since the outflow port of the gas in the pressure chamber 21 and the capillary 10 is limited to the first end 11, even if the absolute value of the voltage change rate is increased, the rapid deformation of the drive unit 50 will not affect the gas pressure. easily suppressed by On the other hand, the valve 23 is opened during the period of increasing the volume of the pressure chamber 21 (time points t5 to t6). Therefore, the effect of suppressing rapid deformation of the drive unit 50 due to the gas pressure as described above is reduced. Under these circumstances, by making the absolute value of the rate of change in voltage when increasing smaller than the absolute value of the rate of change in voltage when decreasing, the load applied to driving section 50 when increasing is reduced. be. From another point of view, it is possible to reduce the load on the driving section 50 while rapidly deforming the driving section 50 in each increase or decrease.

In addition, in this embodiment, the through holes (10a and 10b) penetrating from the first end 11 to the second end 12 of the capillary 10 are replaced by the first holes (tip member 14) opening at the first end 11. and a second hole (hole 10b of the glass tube 13) located on the second end 12 side with respect to the hole 10a. The inner surface of the hole 10b has lower water repellency than the inner surface of the hole 10a. In the pre-wash suction step (FIG. 7(b)), the pre-wash liquid is sucked only into the hole 10a out of the holes 10a and 10b.

Therefore, for example, the pre-washing liquid is less likely to remain in the capillary 10 . As a result, the accuracy of the suction amount of the first liquid (liquid to be measured) thereafter can be improved.

In the above embodiments, the volume corresponding to potential Va0 at time t3-0 is an example of the initial volume. The volume corresponding to potential Va1 at time t3-1 is an example of the first volume. The volume corresponding to potential Va2 at time t3-2 is an example of the second volume. The amount of increase in the volume of the pressure chamber 21 corresponding to the increase from the potential Va0 to Va2 (time t3) is an example of the first amount of increase. The amount of increase in the volume of the pressure chamber 21 corresponding to the increase from the potential Va2 to Va3 (time points t5 to t6) is an example of the second amount of increase. The decrease amount of the volume of the pressure chamber 21 corresponding to the decrease from the potential Va3 to Va0 (time points t8 to t9) is an example of the first decrease amount. The hole 10a of the tip member 14 is an example of a first hole. The hole 10b of the glass tube 13 is an example of the second hole.

The technology according to the present disclosure is not limited to the above embodiments and modifications, and may be implemented in various ways.

Not all of the steps shown in FIGS. 4 and 5 need to be performed. For example, in an extreme example, all steps except the pre-wash step SB and the first suction step SE may be omitted. Conversely, other steps may be added in addition to the steps shown in FIGS. For example, a step of aspirating a third liquid following the second liquid may be added. From another point of view, pipettes are not limited to those capable of mixing two liquids. For example, a pipette may only aspirate one liquid. Conversely, the pipette may be capable of aspirating three or more liquids.

The control section may control the driving section and the valve based on appropriate information. In the embodiment, the controller 24 controlled the actuators and valves based on the signal from the operation part 25 , the passage of time and/or the signal from the controller 105 . In addition, for example, control may be performed based on signals from suitable sensors.

DESCRIPTION OF SYMBOLS 1... Pipette, 10... Capillary, 11... 1st end, 12... 2nd end, 21... Pressure chamber, 23... Valve, 24... Control part, 50... Drive part, 107... Container, 151... Container, LW... Plate Wash liquid.

Claims (6)

a capillary whose first and second ends, which are both ends in the length direction, are open;
a pressure chamber communicating with the interior of the capillary through the second end;
a drive unit that changes the volume of the pressure chamber;
an openable/closable valve that connects the pressure chamber and the outside;
A pre-wash method for cleaning the capillary of a pipette comprising:
a liquid contacting step of contacting the first end with a pre-wash liquid stored in a container;
After the liquid contacting step, with the first end in contact with the pre-washing liquid, the drive unit is controlled to increase the volume of the pressure chamber to supply the pre-washing liquid to the capillary. an aspiration step of aspirating;
After the suction step, with the first end in contact with the prewashing liquid, the drive unit is controlled to reduce the volume of the pressure chamber to discharge the prewashing liquid from the capillary. a dispensing step to
After the discharging step, a liquid separation step of pulling up the capillary from the pre-washing liquid stored in the container;
and
In the suction step, with the valve closed, the driving unit is controlled to increase the volume of the pressure chamber by a first increment to suck the prewash liquid into the capillary;
In the discharging step, the valve is opened, the drive unit is controlled to increase the volume of the pressure chamber by a second increment while the valve is open, the valve is closed, and the valve is closed. The drive unit is controlled to reduce the volume of the pressure chamber by a first decrease amount whose absolute value is larger than the first increase amount, and the pre-washing liquid is discharged from the capillary.
pre-wash method. In the suction step, the volume of the pressure chamber is increased from an initial volume to a first volume, decreased from the first volume to a second volume greater than the initial volume, and the driving is performed to maintain the second volume. 2. The prewash method of claim 1, further comprising controlling a part. The drive unit has a configuration that changes the volume of the pressure chamber to a volume corresponding to the applied voltage,
When the volume of the pressure chamber is increased by the second increase amount, the absolute value of the rate of change of the voltage applied to the drive unit is the same as that of the drive unit when the volume of the pressure chamber is decreased by the first decrease amount. 3. The pre-washing method according to claim 1 or 2, which is smaller than the absolute value of the rate of change of the voltage applied to the part. the through-hole penetrating from the first end to the second end of the capillary,
a first hole opening at the first end;
a second hole located on the second end side with respect to the first hole and having an inner surface with lower water repellency than the inner surface of the first hole,
The pre-washing method according to any one of claims 1 to 3 , wherein in the suction step, the pre-washing liquid is sucked only into the first hole out of the first hole and the second hole. a pipette structure;
a movement mechanism for relatively moving the pipette structure and a container that stores liquid to be sucked into the pipette structure;
a control unit that controls the pipette structure and the movement mechanism;
and
The pipette structure is
a capillary whose first and second ends, which are both ends in the length direction, are open;
a pressure chamber communicating with the interior of the capillary through the second end;
a drive unit that changes the volume of the pressure chamber;
a valve that can be opened and closed to connect the pressure chamber and the outside,
The control unit
moving the first end into the container and, with the first end positioned in the container, increasing the volume of the pressure chamber by a first increment with the valve closed ;
After increasing by the first increment, increasing the volume of the pressure chamber by a second increment while the valve is open;
After increasing by the second increase amount, decreasing by a first decrease amount whose absolute value is larger than the first increase amount with the valve closed ,
controlling the moving mechanism , the drive unit and the valve so as to move the first end out of the container after decreasing by the first decreasing amount . a capillary whose first and second ends, which are both ends in the length direction, are open;
a pressure chamber communicating with the interior of the capillary through the second end;
a drive unit that changes the volume of the pressure chamber;
an openable/closable valve that connects the pressure chamber and the outside;
a control unit that controls the driving unit and the valve ;
and
The control unit stores a timetable that defines the operation of the driving unit, controls the driving unit and the valve according to the timetable,
The timetable is
increasing the volume of the pressure chamber by a first increment with the valve closed ;
After increasing by the first increment, increasing the volume of the pressure chamber by a second increment while the valve is open;
A pipette defining an operation in which, after increasing by said second increment, decreasing by a first decrement greater in absolute value than said first increment with said valve closed .

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