JPH06289032A - Dispensing method for automatic analyzer and dispensing system - Google Patents

Abstract

PURPOSE:To provide a dispensing method and system for automatic analyzer in which carryover of the dispensed solution is avoided and dispensing accuracy is improved to be proper for fine dispensing. CONSTITUTION:A dispensing system 10 of an automatic analyzer is provided with a preparation means 31 in an automatic analyzer for absorbing reserved solution liquid in a pipet 12 by the operation of a dispensing pump 25 from a vessel 30 reserving such a sample to be measured or a solution as reagent, discharging the absorbed liquid to the reaction vessel and dispensing it. In the means 31, the pipet 12 is detachable loaded by pipet tip 28 at the end of a pipet probe 23, unifies the wettability of the solution in the pipet tip 28 and the gas and liquid temperature inside the pipet 12 is balanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dispensing method and a dispensing system for an automatic analyzer used for a sample test such as biochemical analysis and immunoassay, and more particularly to an automatic analyzer employing a disposable chip method. Regarding a dispensing method and a dispensing system.

[0002]

2. Description of the Related Art An automatic analyzer is used as a sample inspection device such as a biochemical analyzer and an immunoassay device used in the field of clinical examination. In this automatic analyzer, a dispensing system that quantitatively dispenses the sample to be measured and the reagent solution contained in the sample container and reagent container in which the sample such as serum is stored in the reaction container using a pipette. Is provided.

Dispensing systems are roughly classified into two types, that is, a cleaning system and a disposable chip system. The cleaning method is a method to prevent contamination (carryover) caused by bringing in different solutions by cleaning the inner and outer surfaces of the pipette tip that dispenses the sample to be measured or reagent solution quantitatively every time. The method is a method that can completely prevent carryover by making the tip of the pipette a disposable tip.

The dispensing system which adopts the disposable chip system has a high sensitivity item (concentration 10
^-9 g / ml or less, concentration range 0 to 10 ⁶ ) is required, and it is widely used in automatic analyzers that require strict carryoverlessness.

The conventional dispensing system of the disposable chip type is constructed as shown in FIG. This dispensing system includes a dispensing arm mechanism 1 driven by a pipette moving mechanism (not shown), and the dispensing arm mechanism 1 is composed of a link mechanism having two rotation axes A and B.

A pipette 3 for dispensing a sample to be measured such as a sample or a reagent is attached to the free end of the tip arm 2 of the dispensing arm mechanism 1. The pipette 3 has a disposable pipette tip 3b at the tip of the pipette probe 3a.
It is configured by detachably mounting.

The pipette tips 3b are arranged and stored on the tip rack 4, and the pipette 3 is moved to a predetermined disposable pipette tip 3b placed on the tip rack 4 and lowered to be mounted as required. By performing the operation, the pipette tip 3b is attached to the probe tip of the pipette probe 3a.

Pipette 3 equipped with a pipette tip 3b
Then moves to a predetermined position on the sampler 5, and a predetermined amount of solution such as the sample to be measured (or reagent) is sucked from the sample container (or reagent container) 6 as a sample container at this predetermined position. The pipette 3 that has sucked the solution such as the sample to be measured is then transferred to a predetermined position on the reaction rack 7, and the solution in the pipette chip 3b at this position is the reaction container 8 in which the solution such as the reagent is dispensed in advance. It is discharged into and dispensed. The sample to be measured and the reagent dispensed to the reaction container 8 are mixed and stirred, and then reacted for a predetermined time, and the concentration of this reaction product is measured by absorbance, fluorescence intensity, etc. by a reaction measurement system (not shown), It is detecting.

On the other hand, the pipette 3 which has been dispensed is transferred onto the tip disposal rack 9, where the pipette tip 3b is placed.
The discard operation is performed. After discarding the pipette tip 3b, the pipette 3 is transferred to a required disposable pipette tip 3b on the tip rack 4 for the next dispensing operation, and the next dispensing operation is cyclically repeated again.

[0010]

The conventional dispensing system employing the disposable chip method in the automatic analyzer has the following problems.

(1) When a solution such as a sample to be measured is sucked, discharged and dispensed by a disposable chip dispensing system, the solution slightly remains on the inner and outer peripheral wall surfaces of the pipette tip 3b, but individual pipettes Since the surface states of the chips 3b are different from each other, the residual liquid amount varies.
Not a certain amount.

(2) The inside of the pipette (from the syringe portion of the dispensing pump to the tip of the pipette tip) is usually filled with an air layer, and the temperature of the solution is not the same as the temperature when the refrigerated reagent is dispensed as a solution. When they are different, the volume of the air layer in the pipette 3 decreases due to the solution suction into the pipette tip 3b, and the solution suction amount increases above a predetermined amount.

(3) Since the pipette tip 3b has water repellency, the surface tension between the solution and the pipette tip 3b is large. Due to the influence of the large surface tension and the air layer, the syringe stroke volume of the dispensing pump and the solution suction amount are different, which makes it difficult to accurately suck the solution.

Due to these factors, it is the current situation that the conventional disposable chip dispensing system cannot sufficiently secure the dispensing accuracy when a small amount of the solution is dispensed. In particular, in the dispensing of a solution containing an amphipathic substance (a substance having both hydrophobicity and water-immersion property) such as serum or enzyme reaction substrate, the dispensing accuracy is significantly deteriorated. Therefore, in developing an automatic analyzer such as an immunoassay device that requires dispensing of a solution of an amphipathic substance, securing a dispensing accuracy has been a major issue.

The present invention has been made in consideration of the above-mentioned circumstances, and aims at making a carry-overless of a dispensed solution and improving dispense accuracy, and a dispense method of an automatic analyzer suitable for a trace amount dispense. And to provide a dispensing system.

Another object of the present invention is to provide a dispensing method for an automatic analyzer which secures a substantially uniform wettability in the pipette and eliminates the gas-liquid temperature difference inside the pipette to improve the dispensing accuracy. Providing a dispensing system.

Still another object of the present invention is to improve the wettability inside the pipette, perform suction and discharge accurately according to the syringe stroke volume of the dispensing pump, improve the dispensing accuracy, and improve the reliability of the device. An object of the present invention is to provide a dispensing method and a dispensing system for an automatic analyzer with improved performance.

[0018]

In order to solve the above-mentioned problems, the dispensing method for an automatic analyzer according to the present invention has a pipette tip attached to the tip of a pipette probe of a pipette as set forth in claim 1. Then, the pipette tip is immersed in a solution such as the sample to be measured or a reagent, and preliminary aspiration and discharge of the solution are performed.After that, the solution is aspirated into the pipette tip and the aspirated solution is placed in a reaction container. This is a method of discharging a predetermined amount and dispensing.

Further, in order to solve the above-mentioned problems, the dispensing method of the automatic analyzer according to the present invention is, in addition to the contents described in claim 1, as described in claim 2, inside the pipette tip. When sucking the solution, the suction amount of the solution is sucked more than the dispensed amount of the solution, and as described in claim 3, the pipette tip is immersed in the solution, and the preliminary suction to the inside of the pipette tip is performed. This is a method of repeating suction / discharge a plurality of times.

On the other hand, in order to solve the above-mentioned problems, the dispensing system of the automatic analyzer according to the present invention, as described in claim 4, dispenses from a container in which a solution such as a sample to be measured or a reagent is stored. By operating the injection pump, the stored solution is sucked into the pipette, and the sucked solution is discharged into the reaction container.
In an automatic analyzer for dispensing, the pipette is detachably attached to the tip of the pipette probe, while the wettability of the solution in the pipette tip is made uniform and the gas-liquid temperature inside the pipette is equilibrated. It is the one that provided the appropriate means.

Further, in order to solve the above-mentioned problems, the dispensing system of the automatic analyzer according to the present invention is characterized in that:
In addition to the contents described in, as described in claim 5,
The preliminary means is a pipette lifting means for immersing a pipette tip of a pipette in and out of a solution in a selected container, and a preliminary suction and discharge into the pipette tip while the pipette tip is immersed in the solution. It is provided with a preliminary supply / discharge means.

Further, in order to solve the above-mentioned problems, the dispensing system of the automatic analyzer according to the present invention, as described in claim 6, dispenses from a container storing a solution such as a sample to be measured or a reagent. By operating the injection pump, the stored solution is sucked into the pipette, and the sucked solution is discharged into the reaction container.
In an automatic analyzer for dispensing, pipette transfer means for selectively transferring the pipette among a pipette tip mounting position, a solution suction position, a solution discharge dispenser and a pipette chip discarding position, and a container at the solution suction position. Preliminary suction and discharge means for preliminarily sucking and discharging the stored solution into the pipette tip of the pipette, and solution suction means for sucking the solution into the pipette tip after preliminary suction and discharge,
It has a solution ejecting means for ejecting the solution sucked into the pipette tip into the reaction container at the solution ejecting and dispensing position to dispense the solution.

Further, in order to solve the above-mentioned problems, the dispensing system of the automatic analyzer according to the present invention has the following features in addition to the contents described in claim 6,
The preliminary means, the solution suction means, and the solution discharge means share a dispensing pump with a syringe provided in a pipette, a pump drive device for driving the dispensing pump, and a drive unit for controlling the operation of the pump drive device. Be prepared.

[0024]

In the dispensing system of this automatic analyzer,
Before dispensing the solution with a pipette by a preliminary means, the solution stored in the container is preliminarily sucked and discharged into the pipette tip to make the inside of the pipette wet and the inner surface of the pipette tip wet. The inner surface of the pipette tip is evenly wetted.

By making the inner surface of the pipette tip uniformly wet by the preliminary means, the surface tension between the inner surface of the pipette tip and the solution is lowered, and when the dispensing solution is sucked into the pipette tip by the dispensing pump, Accurate solution suction is possible. Also, by operating the preliminary means, by performing preliminary suction / discharge of the solution in the pipette tip,
There is no difference between the temperature of the air layer in the pipette tip and the temperature of the solution, and by eliminating this difference in gas-liquid temperature, fluctuations in the amount of solution suction due to volume changes in the air layer are reduced.

Further, by the preliminary means, preliminary suction / discharge is performed before sucking the solution into the pipette tip, so that the adverse effect of variations in the solution remaining in the pipette tip after dispensing the solution is eliminated. You can

In this dispensing system, since the removable pipette tip is used for the pipette probe of the pipette,
It becomes a disposable tip type, and it is possible to achieve carryover of the dispensing solution, while improving the dispensing accuracy by eliminating the gas-liquid temperature difference inside the pipette while ensuring almost even wettability inside the pipette. This makes it suitable for microdispensing.

Further, since the suction and the discharge are accurately performed according to the syringe stroke volume of the dispensing pump and the dispensing accuracy can be improved, the reliability of the device is also improved.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows in principle an embodiment of a dispensing system for an automatic analyzer according to the present invention. Since the overall layout of the dispensing system 1 is basically the same as that of the typical dispensing system shown in FIG. 5, the dispensing system of FIG. 5 is referred to for the basic layout.

In the dispensing system 10 of the automatic analyzer, a pipette 12 is provided at a free end of a dispensing arm mechanism 11 composed of a link mechanism. The dispensing arm mechanism 11 has two rotation axes A and B, and has a base arm 13 and a tip arm 14.
It is a pipette transfer means composed of a link mechanism that can be folded in two from, and the pipette 12 is moved to the pipette tip mounting position E, the solution suction position F and the solution shown in FIG. It is adapted to be selectively transferred between the discharge / dispensing position G and the pipette tip discarding position H.

The base arm 13 and its tip arm 14 of the dispensing arm mechanism 11 are rotated by the arm driving means 16 and 17 including stepping motors and the like, respectively.
These arm driving means 16 and 1 are driven to rotate around.
The operation of 7 is controlled by a driver unit 18. The driver unit 18 is a unit controller 1 such as a CPU
The drive is program-controlled by 9. A program necessary for the dispensing operation of the automatic analyzer is previously installed and set in the unit controller 19.

Further, the pipette 12 mounted on the free end of the dispensing arm mechanism 11 is attached so as to be able to move up and down by a pipette elevating means 20 such as a stepping motor. The operation of the pipette lifting means 20 is performed by the driver unit 18
Controlled by.

On the other hand, the pipette 12 has a pipette probe 23 provided with a dispensing pump 25 with a syringe 24 constituting a positive displacement pump. The dispensing pump 25 is driven by a pump driving device 26 such as a pump motor. Controlled by. The pump drive device 26 is operation-controlled by the driver unit 18.

In the pipette 12, a disposable pipette tip 28 is detachably and airtightly attached to the probe tip of a pipette probe 23. The pipette 12 is composed of a pipette probe 23 having a dispensing pump 25 and a pipette tip 28, and a pump chamber 29 inside the pipette 12.
Is formed. The syringe 24 is freely stroked in and out of the pump chamber 29 inside the pipette 12 by the operation of the pump drive device 26, and the pumping function is exhibited by the stroke action of the syringe 24.

Air is filled from the pump chamber 29 in the pipette 12 to the pipette tip 28 to form an air layer.
Can be raised and lowered by.

This dispensing system 10 has a solution suction position F.
The container 30 storing a sample to be measured such as serum or a solution such as a reagent can be accessed from the container 30.
Preliminary suction and discharge of the solution into the pipette tip 28 are performed by the preliminary means 31 while being immersed in the solution therein.

This preliminary means 31 is based on the pipette tip 2
A pipette raising / lowering means 20 for freely immersing 8 into and out of the solution in the container 30 and a preliminary feeding / discharging means 32 for performing preliminary suction into the pipette tip in a state where the pipette tip is immersed in the solution are provided. The preliminary feeding / discharging means 32 is the dispensing pump 25.
And a pump drive device 26 are combined, and the operation is controlled by a drive signal from the driver unit 18. The preliminary feeding / discharging means 32 is a solution suction means for sucking the solution into the pipette tip 28 when dispensing the solution,
It also serves as a solution ejecting means for ejecting the sucked solution into the reaction container 8 (see FIG. 5) at the solution ejecting and dispensing position G.

Next, the operation of the dispensing system of the automatic analyzer will be described.

Using this dispensing system 10, a reaction container 8
An example of system operation when a sample solution such as a sample to be measured is dispensed will be described.

The unit controller 19 is operated based on a preset predetermined program, and the unit controller 19 outputs an output signal based on the predetermined program to the driver unit 18 to drive the driver unit 18.

The drive signals from the driver unit 18 are used to control the operation of the arm driving means 16 and 17 and the pipette lifting means 20 to transfer the pipette 12 to the pipette tip mounting position E, where the pipette probe 23 has a tip end. Fit the pipette tip 28.

Pipette 1 equipped with a pipette tip 28
2 is subsequently moved onto the sample container 30 by the operation of the arm driving means 16 and 17 and the pipette elevating means 20, and then by the operation of the pipette elevating means 20, as shown in FIG. Move down inside. And
The lowering operation is stopped while the tip portion of the pipette tip 28 is immersed in the sample (reagent) solution stored in the sample container 30 by a predetermined amount. For the lifting operation of the pipette 12, position information is programmed in advance in the unit controller 19 so that the lowering operation is stopped when the tip of the pipette tip 28 reaches a predetermined position in the sample container 30, or This is performed by using a liquid level sensor (not shown) to feed back this sensor detection signal to the pipette lifting means 20 and controlling the lifting.

After the lowering operation of the pipette 12 is stopped, the preliminary means 31 is operated and the dispenser pump 25 is driven by the pump drive device 26. By driving the dispensing pump 25, the sample solution in the sample container 30 is preliminarily sucked.
The suction amount at this time is several μl to several 1 from the actual solution dispensing amount.
0 μl more is set, and preferably (dispensing volume + 2
0 μl).

Next, the preliminary feeding / discharging means 3 of the preliminary means 31.
2 is operated and controlled, the dispensing pump 25 is reversely driven, and the entire amount of the solution sucked into the pipette tip 28 is discharged into the sample container 30 as shown in FIG. 2 (B). At this time, in order to prevent the solution from accumulating at the tip of the pipette tip 28,
The tip of the pipette tip 28 is not pulled out from the solution, and the ejection action is performed in the state of being immersed.

By the suction / discharge operation of the solution by the operation of the preliminary supply / discharge means 32 of the preliminary means 31, the inner peripheral wall surface of the pipette tip 28 is kept in a constant wet state, and the inner surface of the pipette tip 28 and the solution are The surface tension between them can be reduced, and the surface state of the pipette tip 28 can be brought into a uniform wet state. In addition, a preliminary suction of the solution
By discharging, it is possible to eliminate the temperature difference between the solution temperature and the pipette tip in the dispensing pump 25, for example, the temperature of the air layer between the syringe and the pipette tip, and suction or discharge in accordance with the syringe stroke volume of the dispensing pump 25. Can be done accurately.

Next, the dispensing pump 25 is driven again to suck the solution into the pipette tip 28 again as shown in FIG. 2 (C). The suction amount at this time is set to be larger than the actual solution dispensing amount, and for example, the suction amount is (solution dispensing amount + 10 μm).
l). After performing a required amount of suction into the pipette tip 28, the dispensing pump 25 is slightly operated in the discharge direction to correct the backlash associated with the solution suction.
This is performed as shown in (D).

The pipette lifting means 20 is operated to pull up the pipette 12 from the sample container 30 in a state where a required amount of the solution has been sucked into the pipette tip 28, and then the arm driving means 16 and 17 are operated to cause the pipette 12 to react. The container 8 is transferred to the set solution discharge / dispensing position G.
At this solution discharge / dispensing position G, the pipette lifting means 20 is again used.
Is operated to lower the pipette 12 by a predetermined amount. After this lowering operation, the dispensing pump 25 is driven to discharge a predetermined amount of the solution into the reaction container 8 as shown in FIG.

After discharging the sucked solution into the pipette tip 28, a reagent is dispensed into the reaction container 8 in advance in order to prevent the liquid droplets from remaining at the tip of the pipette tip 28. Pipette tip 28 into the reagent
It is desirable to perform the ejection in a state where the tip end portion of the above is immersed, but it is not necessarily limited to this.

After the solution is discharged and dispensed into the reaction container 8, the pipette lifting means 20 and arm driving means 16 and 17 are used.
Is operated to move the pipette 12 onto the tip disposal rack 9 shown in FIG. 5, the pipette tip 28 is detached from the pipette probe 23 at the tip disposal position H, and the pipette tip 28 is discarded.

FIG. 3 is an embodiment showing another procedure for dispensing the sample solution into the reaction container by using the dispensing system of the automatic analyzer.

Also in this dispensing system, the pipette 1
2 attaches the pipette probe 23 to the tip of the pipette probe 23, and then moves the pipette 12 attached with the pipette probe 23 onto the sample container 30.

Pipette 1 transferred to this sample container 30
2 is subsequently lowered by the operation of the pipette elevating means 20 to be stopped, and the sample solution in the sample container 30 is accessed. After stopping the lowering operation of the pipette 12, the preliminary means 31 is operated at the solution suction position F to preliminarily suck the required amount of the solution in the sample container 30 into the pipette tip 28 (FIG. 3A). .

After preliminarily suctioning the pipette tip 28 into the pipette tip 28 as shown in FIG. 3 (A), the entire amount of the suctioned solution is discharged while the tip portion of the pipette tip 28 is immersed in the stored solution in the sample container 30. (FIG. 3 (B)).

After the preliminary suction / discharge operation of the solution into the pipette tip 28 by the preliminary supply / discharge means 32 of the preliminary means 31 is repeated one or more times, preferably a plurality of times, the pipette lifting means 20 is operated, The tip of the pipette tip 28 is once lifted from the liquid surface of the sample container 30 as shown in FIG. 3C, and the dispensing pump 25 is moved to a lifted position away from the liquid surface.
The backlash is corrected by operating the pump drive device 26 in the suction direction.

After correcting the backlash, the pipette elevating means 20 is again operated to lower the pipette, and the tip end of the pipette 12 is dipped into the solution in the sample container 30 by a certain amount. In this immersion state, the descending operation of the pipette 12 is stopped, and the dispensing pump 25, which is a solution suction means, is driven so that a predetermined dispensed amount of the solution is placed in the pipette probe 23.
Aspirate as shown in (D).

After the pipette probe 23 sucks a predetermined amount of the solution, the pipette elevating means 20 and the arm driving means 16 and 17 are operated to move the pipette 12 to the solution discharge / dispensing position G on the reaction container 8. Transfer.

At the solution discharge / dispensing position G, the tip end of the pipette tip 28 is lowered by a certain amount so as to be immersed in the stored solution (reagent) in the reaction vessel 8, and then the dispensing pump 2
5 is driven to discharge and dispense the entire amount of the solution sucked into the pipette tip 28 (FIG. 3 (E)).

At the time of discharging and dispensing the solution, the dispensing pump 25 is operated while the tip portion of the pipette tip 28 is kept immersed in the stored solution, and the solution is dispensed as shown in FIGS. 3 (F) and 3 (G). Repeat suction and discharge action. With the tip portion of the pipette tip still immersed in the stored solution, the dispensing pump 25 is alternately driven in the suction / discharge direction to repeat suction / total amount discharge in the reaction container 8 to suck a predetermined amount in the pipette tip 28. Dispense the solution completely and dispense.

A series of solution suction by the dispensing frame 10
After performing the dispensing operation, the pipette lifting means 20 and the arm driving means 16 and 17 are operated to move the pipette 12 onto the tip disposal rack 9, and the pipette tip 28 is placed in the tip disposal rack 9 at the tip disposal position H. To discard.

FIG. 4 shows an evaluation experiment example and an evaluation result in which the dispensing accuracy when the solution is dispensed using this dispensing system 10 is compared with the dispensing accuracy of the conventional dispensing system.

The dispensing accuracy was evaluated by weighing the weight of the sample serum to be dispensed using a precision balance. Repeat dispensing 20 times under the same conditions,
The CV (variation coefficient) value was calculated and used as the evaluation value of the dispensing accuracy. Here, the CV value is expressed by the following equation.

[0063]

[Equation 1]

Using this dispensing system 10, FIG.
~ (E) is applied to perform preliminary suction and discharge operations of serum as a sample to be measured before solution dispensing, and then, when the solution is dispensed, the suction amount is made larger than the discharge amount. The operation of leaving the solution in the pipette tip 28
It is shown in FIG. 4 and compared with that using a conventional dispensing system. As a result, as shown in FIG. 4, when 20 μl of the solution was dispensed, the dispensing accuracy was 2.8% to 0.5% in CV value.
In addition, when dispensing 10 μl of solution, the dispensing accuracy is 3.2%.
From 1.5% to a significant improvement. It has been proved that the dispensing accuracy is greatly improved by applying it to this dispensing system.

[0065]

As described above, in the present invention,
Before dispensing the solution with a pipette by a preliminary means, the solution stored in the container is preliminarily sucked and discharged into the pipette tip to make the inside of the pipette wet and the inner surface of the pipette tip wet. The inner surface of the pipette tip is evenly wetted.

By making the inner surface of the pipette tip uniformly wet by the preliminary means, the surface tension between the inner surface of the pipette tip and the solution is lowered, and when the dispensing solution is sucked into the pipette tip by the dispensing pump, Accurate solution suction is possible, which is suitable for dispensing a small amount of solution. Also,
By preliminarily sucking and discharging the solution into the pipette tip by the operation of the preliminary means, there is no difference between the temperature of the air layer inside the pipette tip and the temperature of the solution. Fluctuations in the amount of solution sucked due to volume changes are also reduced, and dispensing accuracy is further improved.

Furthermore, by performing preliminary suction / discharge before sucking the solution into the pipette tip by the preliminary means, it is possible to eliminate the adverse effect of variations in the solution remaining in the pipette tip after dispensing the solution. You can

In this dispensing system, since the removable pipette tip is used for the pipette probe of the pipette,
Disposable tip type ensures reliable carryover of the dispensed solution, while improving the dispensing accuracy by eliminating the gas-liquid temperature difference inside the pipette while ensuring almost uniform wettability inside the pipette. Therefore, it becomes suitable for microdispensing.

Further, since the suction and the discharge are accurately performed according to the syringe stroke volume of the dispensing pump and the dispensing accuracy can be improved, the reliability of the device is also improved.

[Brief description of drawings]

FIG. 1 is a view showing in principle an embodiment of a dispensing system of an automatic analyzer according to the present invention.

FIG. 2 is a process chart showing an example of a solution dispensing action using the dispensing system of the automatic analyzer according to the present invention in time series.

FIG. 3 is a process chart showing another example of solution dispensing action using the dispensing system of the automatic analyzer according to the present invention in time series.

FIG. 4 is a diagram showing the dispensing accuracy using the dispensing system of the automatic analyzer of the present invention in comparison with the dispensing accuracy of the conventional dispensing system.

FIG. 5 is a view showing a typical example of a conventional dispensing system for an automatic analyzer.

[Explanation of symbols]

 10 dispensing system 11 dispensing arm mechanism (pipette transfer means) 12 pipette 13 base arm 14 tip arm 16,17 arm driving means 18 driver unit 19 unit controller 20 pipette lifting means 23 pipette probe 24 syringe 25 dispensing pump 26 pump drive Device 28 Pipette tip 30 Container 31 Preliminary means 32 Preliminary supply / discharge means (solution suction means, solution discharge means)

Claims (7)

[Claims] 1. A pipette tip is attached to the tip of a pipette probe of a pipette, and then the solution is preliminarily sucked and discharged while the pipette tip is immersed in a solution such as a sample to be measured or a reagent. A dispensing method for an automatic analyzer, which comprises sucking a solution into a container, discharging the sucked solution into a reaction container by a predetermined amount, and dispensing the solution. 2. The dispensing method for an automatic analyzer according to claim 1, wherein when the solution is sucked into the pipette tip, the suction amount of the solution is sucked more than the dispensing amount of the solution. 3. The dispensing method for an automatic analyzer according to claim 1, wherein preliminary suction / discharge into the interior of the pipette tip is repeated a plurality of times while the pipette tip is immersed in the solution. 4. An automatic analyzer for sucking a stored solution into a pipette by operating a dispensing pump from a container storing a solution such as a sample to be measured or a reagent and discharging the sucked solution into a reaction container for dispensing. In the above pipette, a pipette tip is detachably attached to the tip of the pipette probe, and a preliminary means is provided for making the wettability of the solution in the pipette tip uniform and for equilibrating the gas-liquid temperature inside the pipette. Dispensing system for automatic analyzers. 5. Preliminary means include pipette lifting means for immersing a pipette tip of a pipette in and out of a solution in a selected container, and preparatory means for immersing the pipette tip in the solution while the pipette tip is immersed in the solution. The dispensing system for an automatic analyzer according to claim 4, further comprising a preliminary supply / discharge means for performing suction and discharge. 6. An automatic analyzer for sucking a stored solution into a pipette by operating a dispensing pump from a container storing a solution such as a sample to be measured or a reagent and discharging the sucked solution into a reaction container for dispensing. A pipette transfer means for selectively transferring the pipette among a pipette tip mounting position, a solution suction position, a solution discharge / dispensing position, and a pipette tip discarding position, and a pipette of a solution stored in a container at the solution suction position. Preliminary suction and discharge means for preliminarily sucking and discharging into the pipette tip, solution suction means for sucking solution into the pipette tip after preliminarily suctioning and discharging, and solution discharge dispensing of the solution sucked into the pipette tip A dispensing system for an automatic analyzer, comprising: a solution ejecting means for ejecting into a reaction container at a position to dispense. 7. The preparatory means, the solution suction means, and the solution discharge means are a dispensing pump with a syringe provided in a pipette, a pump driving device for driving the dispensing pump, and an operation control of the pump driving device. 7. The dispensing system for an automatic analyzer according to claim 6, wherein a drive unit for performing is provided in common.