JP2001324510A - Variable discharge capacity liquid dispensation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a variable discharge capacity liquid dispensation device and a variable discharge capacity automatic liquid separation system capable of making an addition amount of sample a desired value in various forms such as per well W, per row or per line and having high degree of precision and high degree of accuracy, general-purpose property, and high easiness for use. SOLUTION: Pumps P taking out liquid samples collected in a tank T are provided by corresponding to each pipette 31, and the pumps P are controlled by a control part 60 to pour a predetermined amount of liquid samples independently into wells W in each row or each line from each pipette 31.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dispensing device for dispensing a liquid sample into a multiwell plate used for clinical diagnosis and the like, and an automatic liquid dispensing system using the dispensing device. Variable volume liquid dispensing device and automatic liquid dispensing system that can change the amount of liquid sample dispensed for each well and exhibit excellent precision and accuracy even with a small amount of liquid dispensed About.

[0002]

2. Description of the Related Art For example, in a method for diagnosing AIDS and viral infectious diseases such as hepatitis B and C, etc.
A multi-well plate, commonly called a 96-well plate, is used in which a total of 96 wells (hollows) are arranged in 8 columns and 12 rows at a pitch of 9 mm vertically and horizontally.

[0003] In the current situation of experiments performed using such a multi-well plate, a liquid sample is dispensed to each row of the well or to the whole well at once, instead of adding a liquid sample to each well. The method is taken.

At present, various devices have been put into practical use for efficiently dispensing or diluting a liquid sample into many wells.

For example, in order to dispense a reagent or a buffer into a multi-well plate in one operation, 96 dispensing tips corresponding to each well of the multi-well plate are provided and driven simultaneously. There is a dispensing device that sucks and discharges a liquid by using a piston. However, this piston-type dispensing apparatus cannot supply different amounts of different liquid samples to each well.

[0006] As a method for introducing a different liquid sample into each well with a different liquid amount, a) a handy type multipipettor is used.

B) A single pipetter is used to exchange dispensing tips for each type of liquid.

C) Several types of reservoirs having different types of liquid samples are prepared and dispensed by an automated multi-pipettor, that is, one having a number of pipette heads corresponding to the rows or columns of the multi-well plate.

D) A dispensing robot equipped with one to four suction / drainage probes and freely controlling the amount and type of liquid sample is used. and so on.

[0010]

However, the multipipetter a) and the dispensing tip replacement type b) are not practical because the dispensing operation is extremely inefficient.

The automatic multipipetter c) has the disadvantage that the exchange of tips is complicated and the volume of each tip is fixed, so that the dispensed liquid volume cannot be freely set for each well. However, there is a problem that the number of experiment steps increases and it takes time.

The dispensing robot of the above d) is expensive and complicated in operation, so that there is a problem that maintenance is troublesome to maintain normal functions.

The amount of the liquid sample to be added to each well is, of course, extremely high precision (the dispersion of the measured values when the same volume is measured a plurality of times is extremely small) due to the nature of the experiment. ) And high accuracy (the ratio of the error, which is the difference between the measured value and the true value, to the true value) is required. A function on the order of 10 μl to 10 μl is required, and there is often a demand for dispensing a liquid volume of 1 μl or less.

However, for such a small amount dispensing,
It is important to control the environment in which dispensing operations are performed, but the function of the piston or pump of the pipettor is important, and in the current situation of microdispensing, there are no dispensers that maintain satisfactory precision and accuracy. It is expected to appear early. In addition, this technique of microdispensing is strongly demanded not only in the field of clinical diagnosis, but also in the field of physics and biochemistry research.

An object of the present invention is to make it possible to set the amount of liquid sample to be a desired value in various modes such as for each well, for each column, or for each row, thereby obtaining high precision and accuracy. Another object of the present invention is to provide a versatile and convenient liquid dispensing device with variable discharge capacity and an automatic liquid dispensing system with variable discharge volume.

[0016]

This object is achieved by the following means.

(1) A base, a support arm provided above the upper surface of the base, a transfer unit provided on the upper surface of the base, and a multiwell transferred by the transfer unit A plate, a plurality of pipettes supported by the support arm and suspended to correspond to the wells of each column or each row of the multi-well plate, provided in correspondence with each of the pipettes, and stored in a tank. A pump that takes out the liquid and introduces it into each pipette, and a control unit that controls the driving state of the transport unit and the pump,
The dispensing volume variable liquid dispensing device, wherein the control unit is controlled so that the amount of liquid injected from each pipette to each corresponding well is controlled independently.

(2) The liquid dispensing device with variable discharge capacity, wherein the pump is constituted by a piezo pump.

(3) The dispensing capacity variable liquid dispensing apparatus, wherein the control unit operates the pump simultaneously or with a time difference.

(4) The dispensing capacity variable liquid dispensing apparatus, wherein the pipette is a part of the number of wells in each column or each row.

(5) A liquid dispensing apparatus with a variable discharge capacity, wherein the pipette has a detachable pipette tip at the tip.

(6) A base, a support arm provided above the upper surface of the base, a transfer unit provided on the upper surface of the base, and a multi-well transferred by the transfer unit A plate, a plurality of pipettes supported by the support arm and suspended to correspond to the wells of each column or each row of the multi-well plate, provided in correspondence with each of the pipettes, and stored in a tank. A pump that takes out the liquid and introduces it into each pipette, and a control unit that controls the driving state of the transport unit and the pump,
A variable-volume liquid dispensing device that controls the control unit and controls the amount of liquid to be independently injected into each of the corresponding wells from each of the pipettes. In the vicinity of, one or a plurality of stackers capable of accommodating a large number of multi-well plates are provided, and the multi-well plates are respectively taken out from the stackers by driving the transport unit, and are positioned at the lower part of the pipette, and a pump is disposed. After the liquid is injected into each well by driving, the multi-well plate is transported and stored in the stacker from which the multi-well plate is removed or another stacker by driving the transport unit. Automatic liquid separation system with variable discharge capacity.

[0023]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic perspective view showing a liquid dispensing apparatus with a variable discharge capacity according to an embodiment of the present invention. First, the liquid dispensing apparatus with a variable discharge capacity according to the present embodiment will be briefly described. In FIG. 1, the liquid dispensing apparatus with a variable discharging capacity has a base 10 on which a multi-well plate Mp is placed. Transporting unit 20 for horizontally moving, a plurality of pipettes 31 for injecting each well W in a double row and a double row formed in the multi-well plate Mp, and a support for the liquid injection unit 30 And a supporting portion 40 which is provided.

On the side of the base 10, the liquid injection section 30
Are provided with the same number of tanks T as the pipettes 31 storing the liquids to be supplied to the respective pipettes 31 and pumps P provided in the respective tanks T and for sucking the liquid therein. It constitutes a part of the liquid injection section 30.

On the front surface of the base 10, the transport unit 20
A display unit 50 for displaying the operation of the pump P and the like is provided. The transport unit 20 and the pump P and the like are controlled by a control unit 60 shown in FIG.

This will be described in more detail. FIG. 2 is a plan view of FIG.
1 is a side view of FIG. 1. As shown in FIGS. 2 and 3, the transport unit 20 includes a pair of guide members 21 for guiding both long sides of the multi-well plate Mp and holding the guide members 21 in a horizontal state. Have. These guide members 21
Is fixed to the upper surface of the base 10.

A transport member 23 composed of a roller conveyor or a belt conveyor on which the multi-well plate Mp is placed is provided between the two guide members 21. The transport speed of this transport member 23, the transport start timing, etc. ,
It is controlled by the control unit 60. An extruding member (not shown) for extruding the multi-well plate Mp onto the transport member 23 may be provided on the base 10.

Next, the liquid injection section 30 is supported by a support section 40 and a support arm 41 projecting from the support section 40 toward the upper portion of the base 10. A plurality of through holes (not shown) are opened in the support arm 41, and a pipette 31 having a tapered side surface is detachably inserted and held in each through hole. The pipettes 31 are arranged in a row so as to correspond to the wells W in each row of the multi-well plate Mp, and a detachable pipette tip 31a (see FIG. 5) is provided at each end of the pipette 31. Have been. By doing so, the pipette tip 31a can be replaced while the pipette 31 is supported by the support arm 41, the next experiment can be easily performed, and the experiment work can be simplified and time can be reduced.

Further, depending on the case, the pipettes 31 may not correspond to the wells W in each column of the multi-well plate Mp, but may be the number of wells in each row, or may correspond to only a part of each row in each column. They may be arranged and can be appropriately selected by experiment.

The rear end of each pipette 31 is connected to the conduit 3
2 are connected so that the liquid from the corresponding pump P is independently guided to each pipette 31. Note that these conduits 32 extend beyond the support portion 40 and are connected to the pump P, but are bundled by a clip C on the upper surface of the support portion 40.

In the present embodiment, a piezo pump is used as the pump P. FIG. 4 is a schematic explanatory view showing a piezo pump. As shown in FIG. 4, the piezo pump reciprocates a piston member 34 by means of a laminated piezoelectric actuator 33 to move a diaphragm 35 attached to the tip of the piston member 34 through a membrane. In the pump chamber 36,
The pump chamber 36 is connected to the conduit 32 via check valves V1 and V2 provided at the inlet and outlet of the pump chamber 36, respectively. In addition, the code | symbol "B" in a figure is a spring.

This piezo pump provides a driving signal to the laminated piezoelectric actuator
5, which is a combination of three components: frequency, voltage and waveform.

Here, the frequency is the number of times the diaphragm 35 is operated per unit time, the voltage is the amount of movement of the diaphragm 35, that is, the control of the flow rate, and the waveform is the one that sets the form of the liquid to be discharged. Use continuous ejection when a rectangular wave emits droplets.

If this piezo pump is used, the tank T
Liquid can be discharged even in an extremely small amount of 0.05 μl, and the discharge amount and the discharge pattern can be freely changed by appropriately combining the three elements of the frequency, voltage and waveform. Since the membrane moves, the tip of the pipette 31 can be blown off, and the liquid can be easily drained, resulting in extraordinary convenience. In addition, since the piezo pump does not generate heat, there is no need to worry about temperature denaturation of the separated solution due to heat, and more accurate analysis accuracy can be obtained.

The control of the driving signal is performed by the control unit 60. FIG. 5 is an explanatory diagram showing a control state of the piezo pump. As shown in FIG. 5, the control unit 60 includes a personal computer 61 and a controller 62 controlled by the personal computer 61.
And the controller 62 controls the operation of each of the pumps P.

The personal computer 61 is used not only to set the drive signal output from the controller 62, but also to activate a plurality of piezo pumps at the same time or to activate a plurality of piezo pumps with a time difference. It is also used to set the signal to be triggered. If the pumps P operate at the same time or at different times, the dispensed liquid volume for each well can be set individually.

Next, the operation of the above embodiment will be described by taking as an example a case where the evaluation of the antibody binding ability is carried out by an oxygen binding immunoadsorption test.

First, using a 96-well multi-well plate Mp, an antigen (eg, DNA) for the antibody to be measured is physically adsorbed in each well W and insolubilized.

At this time, if the antigen to be adsorbed is changed for each row, the presence or absence of antibody production for the number of rows can be checked by one operation. Separately, serum is collected from the subject, and serum is collected from the collected blood by centrifugation or the like, and the serum of each subject collected in this manner is placed in each tank T.

Next, the multi-well plate Mp having the antigen bound to the inner wall is moved below the pipette 31 by the transport unit 20, and stops when the first row of wells W is positioned below the pipette 31, and the standby state is established. I do.

On the other hand, the liquid injection section 30 starts the pump P,
The serum in each tank T is sucked up, and each pipette 31 is filled with the serum, and is in a standby state immediately before dropping.

Then, the pump P controlled by the personal computer 61 operates again to inject the liquid into the wells W of the first row of the multi-well plate Mp. Since the pumps P operate independently of each other, a predetermined amount of serum is instantaneously dropped into each of the pipettes 31 connected via the conduits 32, and the liquid is injected.

That is, since a piezo pump is used for the pump P, the laminated piezoelectric actuator 33
A drive signal having a predetermined frequency, voltage and waveform is provided. As a result, the diaphragm 35 moves by a predetermined film, and a predetermined amount of serum is discharged continuously or intermittently.

In particular, in the case of this piezo pump, intermittent ejection is possible by the membrane movement of the diaphragm 35. Therefore, even when a small amount of serum is ejected from each pipette 31, the last serum is well cut and a higher test can be performed. Precision and accuracy will be obtained.

As described above, the result of an experiment on the improvement of precision and accuracy is as follows. For example, even if the injection volume is as small as 1 μl, high precision of about 1.00 μl, ± 0 It has been found that a high accuracy of about 1 μl is guaranteed.

In addition, independently of each pipette 31, the amount of serum used for each antigen-antibody reaction is determined by the type of antigen (ie, column).
If different for each row, this means that the control unit 60 can adjust the amount of serum injected in each row. This means that in the test using the reagent, the concentration gradient of the reagent in each column can be checked.

If the use of the liquid dispensing apparatus of the present invention makes it possible to inject serum with sufficiently high precision and accuracy, it is possible to not only determine the presence or absence of an antibody,
The amount of antibody production can be quantified, which is very preferable.

After the serum is injected into each well W in this manner, each well W is washed with a buffer to remove unbound reactants, and the remaining serum not bound to the antigen bound to the inner wall is removed. Remove protein.

Then, a predetermined amount of purified enzyme-labeled rabbit anti-human immunoglobulin is added to each well W using a commercially available multipipettor or the like, or using the liquid dispensing apparatus of the present invention, and bound on the inner wall. The anti-human immunoglobulin is further specifically bound to the antibody bound to the antigen. In particular, in the latter case, excellent precision and accuracy of the injection amount can be obtained, so that it is particularly useful for the purpose of measuring the antibody titer as described below.

In the latter case, since the type of the solution to be injected is changed from serum to a solution containing purified rabbit anti-human immunoglobulin in which the pipette 31 is enzyme-labeled, the pipette 31 is replaced with a new one or a new one. It is used after a washing solution such as a buffer solution is put in T and the pipette 31 is thoroughly washed.

Finally, by detecting or quantifying the enzyme activity by coloring the enzyme thus bound, the presence or absence of the antibody in the serum and the antibody titer can be measured.

Next, the case where the above-described liquid dispensing apparatus is used for an automatic liquid dispensing system with a variable discharge capacity will be described. Since the liquid dispensing device is the same as that described above, the description is omitted.

FIG. 6 is a front view showing an automatic liquid separation system with variable discharge capacity according to the present invention. As shown in FIG. 6, the configuration of the present system is composed of a first and second multi-well plates Mp configured to accommodate a large number of multi-well plates Mp near both sides of the liquid dispensing device S of variable discharge capacity. Stacker 70,
71, and the transport unit 20 is provided with the both stackers 7
0, 71 and the liquid dispensing device S are extended.

In the present system, first, the transport unit 20 is operated, and one multi-well plate Mp in which an antigen for an antibody to be measured is previously adsorbed in each well W is taken out of the first stacker 70, It is positioned below the pipette 31 by being conveyed by a conveyor.

Then, a predetermined amount of serum is independently injected into each well W by driving the pump P.

After the injection, the transport unit 20 is operated again to remove the multi-well plate Mp from the second stacker 7.
Convey to 1

Such a flow operation is performed for the number of the multi-well plates Mp stored in the first stacker 70, and all the multi-well plates Mp are stored in the second stacker 71.

When the injection of the serum is completed, each tank T
The serum in the container is replaced with a buffer, or the tank T containing the serum is replaced with the tank T containing the buffer. In order to eliminate anxiety about sample contamination, it is preferable to separately prepare a device for dispensing serum and a device for dispensing buffer.

After the replacement, the transport unit 20 is operated again to transport the multi-well plate Mp stored in the second stacker 71 until the multi-well plate Mp is positioned below the pipette 31.

Then, a predetermined amount of buffer is injected into each well W by driving the pump P, and the unbound reactant is washed away as described above, and the remaining serum not bound to the antigen bound to the inner wall is removed. Remove protein.

Thus, the presence or absence of the antibody in the serum,
After measuring the antibody titer, the transport unit 20 is operated, and the multi-well plate Mp is stored in the first stacker 70.

In this way, a large number of multi-well plates Mp can be processed at a time, and serum can be automatically and simply injected into the wells W with high precision and accuracy. This results in an extremely convenient liquid separation system.

Although the above embodiment has been described with reference to the case of the oxygen-binding immunoadsorption test, the present invention is not limited to the above-described embodiment, and other measurement methods,
For example, it can be similarly used for immunofluorescence, radioimmunoassay, and screening of a target recombinant gene in recombinant gene manipulation.

In the liquid separation system, the multi-well plate Mp is taken out from one stacker and transported to the other stacker. However, the present system is not limited to this. The multi-well plate Mp taken out of one stacker may be returned to the stacker.

[0066]

As described above, according to the present invention, the following effects can be obtained.

According to the first aspect of the present invention, the amount of liquid to be injected is controlled independently from each pipette to each of the corresponding wells. In the embodiment described above, the amount of the sample to be added can be set to a desired value, and higher precision and accuracy can be obtained. Also,
Since different types of experiments or trends can be examined on one multiwell plate, versatility and convenience are high.

According to the second aspect of the present invention, since the pump is a piezo pump, a very small amount of sample can be injected, higher precision and accuracy can be obtained, the liquid can be blown off, and the liquid can be easily drained. In addition, since no heat is generated, more accurate analysis can be performed.

According to the third aspect of the present invention, since the control unit operates the pumps simultaneously or with a time difference, various modifications can be made, such as making the reaction time different.

According to the fourth aspect of the present invention, if the pipette is used as a part of the number of wells in each column or each row, different types of experiments or trends can be examined on one multi-well plate. The versatility becomes higher.

According to the fifth aspect of the present invention, since the pipette tip is detachably provided at the tip of the pipette, the next experiment can be easily performed without replacing the entire pipette, thereby facilitating the experimental work. And time can be reduced.

According to the sixth aspect of the present invention, a large number of multi-well plates can be processed at one time, and the serum is automatically and simply injected into the well W with high precision and accuracy. This results in a very convenient liquid separation system.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing an embodiment of the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a side view of FIG. 1;

FIG. 4 is a schematic explanatory view showing a piezo pump.

FIG. 5 is an explanatory diagram showing a control state of a piezo pump.

FIG. 6 is a front view showing a variable discharge capacity automatic liquid separation system of the present invention.

[Explanation of symbols]

 Reference numeral 20: transport unit, 31: pipette, 31a: pipette tip, 60: control unit, P: pump, T: tank, Mp: multi-well plate, W: well.

Claims (6)

[Claims] 1. A base, a support arm provided above the upper surface of the base, a transfer unit provided on the upper surface of the base, and a multi-well plate transferred by the transfer unit And a plurality of pipettes supported by the support arm and suspended to correspond to the wells of each column or each row of the multi-well plate, provided corresponding to each of the pipettes, and stored in a tank. A pump for taking out a liquid and introducing the liquid into each pipette; and a control unit for controlling the driving state of the transport unit and the pump. The control unit is controlled, and each of the pipettes is independently injected into each corresponding well. A dispensing capacity variable liquid dispensing device characterized in that the amount is controlled to inject liquid. 2. The liquid dispensing device according to claim 1, wherein the pump comprises a piezo pump. 3. The liquid dispensing device according to claim 1, wherein the control unit operates the pump simultaneously or with a time difference. 4. The pipette according to claim 1, wherein the pipette is a part of the number of wells in each column or each row.
The liquid dispensing device with variable discharge capacity according to any one of the above. 5. The automatic liquid dispensing apparatus according to claim 1, wherein the pipette has a detachable pipette tip at a tip thereof. 6. A base, a support arm provided above the upper surface of the base, a transfer unit provided on the upper surface of the base, and a multi-well plate transferred by the transfer unit. And a plurality of pipettes supported by the support arm and suspended to correspond to the wells of each column or each row of the multi-well plate, provided for each of the pipettes, and stored in a tank. A pump for taking out a liquid and introducing it to each pipette; and a control unit for controlling the driving state of the transport unit and the pump. The control unit is controlled to independently inject each of the pipettes into a corresponding well. A stacker capable of accommodating a large number of multi-well plates is provided near the discharge capacity variable liquid dispensing apparatus, which has a variable discharge capacity liquid dispensing apparatus that controls the amount to be injected. One or more units are provided, and the multi-well plate is taken out of the stacker by driving the transfer unit, and is placed below the pipette, and the pump is driven to inject the liquid into each well. A variable discharge capacity automatic liquid separation system, wherein the plate is transported and stored in a stacker or another stacker from which the multiwell plate has been taken out by driving the transport unit.