JP3282455B2 - Liquid sampling method and device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for collecting a liquid, and more particularly to a method and an apparatus for collecting a test liquid in a container by using a suction nozzle.

[0002]

2. Description of the Related Art In an analyzer for automatically analyzing a sample such as a biological fluid, a sample is dispensed from a sample container into a reaction container, and a reagent solution is dispensed from a reagent bottle into the reaction container. A mixed solution of a sample and a reagent is measured in a reaction vessel, or the mixed solution is collected by a suction nozzle and guided to a flow cell for measurement.

[0003] When a sample or a reagent is collected, a method is known in which the liquid level in a container is detected along with the dispensing operation in order to prevent the dispensing suction nozzle from entering deeply below the liquid level. . As one of such examples, there is a liquid level detecting device described in Japanese Patent Application Laid-Open No. 4-319624. In this prior art, a sample container is disposed between a pair of opposed electrodes, and a grounded conductive suction nozzle is lowered into the sample container.
Then, by detecting a change in capacitance between the electrodes when the tip of the suction nozzle comes into contact with the liquid surface, it is detected that the suction nozzle has reached the liquid surface of the sample liquid.

As another example of a liquid level detection method, see Japanese Patent Application Laid-Open
There is one described in 109330. This example is a method of detecting that the tip of the suction nozzle has come into contact with the sample liquid surface by discharging or sucking air from the tip of the suction nozzle and detecting a change in pressure in the suction nozzle.

[0005]

By the way, in an automatic analyzer, it is difficult to obtain an accurate analysis result of an analysis item of a sample unless an appropriate amount of a sample, a reagent or a mixture thereof is collected. .

[0006] In this case, if the sample is a biological sample such as blood serum or serum and the analysis item is a substance usually contained such as a protein, it is determined whether an appropriate amount of the test liquid has been collected. Is easy to detect. In other words, as a result of analyzing the sample, if the analysis result that the protein concentration is zero is obtained, this is an impossible state,
The occurrence of a sampling error can be determined by an operator or the like, and can be analyzed again.

However, when the analysis item is an object not contained in a normal biological sample, such as a virus, it is difficult to detect whether or not a sampling error has occurred. In other words, as a result of analyzing a sample, even if it is determined that the sample does not contain a virus, it cannot be determined whether or not the sample is caused by a sampling error.

[0008] The above-mentioned JP-A-4-319624 and JP-A-63-109330 do not disclose a configuration capable of detecting a sampling error.

An object of the present invention is to provide a method and an apparatus for collecting a liquid, which can determine whether or not an appropriate amount of a test liquid has been collected by a suction nozzle.

[0010]

According to a liquid sampling method according to the present invention, before and after an operation of collecting a test liquid contained in a container by a suction nozzle, the amount of the test liquid in the container is adjusted. The physical quantity to be measured is measured, and it is determined whether or not a predetermined amount or more of the test liquid has been collected by the suction nozzle based on the measured values before and after the collection of the test liquid.

The liquid sampling apparatus according to the present invention comprises an ascending and descending suction nozzle for sampling a test liquid contained in a container, and a measurement signal corresponding to the amount of the test liquid in the container. Measuring means for obtaining, storage means for storing a measured value before collection by the measuring means before collecting the test liquid in the container by the suction nozzle, and a test liquid in the container by the suction nozzle. Comparison means for comparing the measured value after collection by the measurement means after collection with the measured value before collection, and determines whether or not a predetermined amount or more of the test liquid has been collected from the container based on the comparison result. And determining means for performing the determination.

[0012]

The test liquid applicable to the present invention includes a biological sample such as blood or urine, a liquid sample that can be analyzed by an automatic analyzer, a reagent for reacting with the sample, and a mixed liquid of the sample and the reagent. Used. The suction nozzle has one form of a pipette nozzle for dispensing a sample or a reagent,
Another form is a sipper nozzle for guiding a mixture of a sample and a reagent to a flow cell.

The amount of the test liquid in the container is not limited to the volume of the test liquid contained in the container, but also means the liquid level of the test liquid in the container. And

In the preferred embodiment of the present invention, the capacitance based on the test solution in the container is measured. However, the method for measuring the amount of the test solution in the container is not limited to this. May be any as long as it can substantially measure the difference in the amount of the test liquid remaining in the container before and after collection of the test liquid by the suction nozzle. However, when measuring the amount of the test liquid by measuring the capacitance, an accurate amount can be obtained by measuring in a state where the suction nozzle is separated from the liquid surface of the test liquid.

When the measurement signal is a capacitance, a sample container is arranged between the first and second electrodes facing each other. In addition, a nozzle made of a conductive material is used for collecting the liquid, and this nozzle is electrically connected to one of the first electrode and the second electrode. The capacitance corresponding to the amount of the test liquid stored in the container is detected, and the detected capacitance is stored in the storage unit. When the nozzle made of a conductive material comes into contact with the liquid surface in the container, the capacitance value of the air between the nozzle and the first or second electrode becomes substantially infinite, and the first and second electrodes become infinite. And the capacitance value rapidly increases.

Therefore, by monitoring the capacitance value between the first and second electrodes and detecting that the capacitance has sharply changed,
The fact that the nozzle has contacted the liquid surface can be detected.

The comparing means compares the measured capacitance value before collecting the test liquid with the measured capacitance value after collecting the test liquid. If there is, the determination means determines that a predetermined amount or more of the test liquid has been collected by the suction nozzle.

In another embodiment, the liquid surface height of the test liquid is measured before and after collecting the test liquid in the suction nozzle, and a predetermined amount or more is measured based on the difference between the measured values before and after collection. It is determined by the determination means whether or not the test liquid is collected in the suction nozzle.

[0019]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 10 is an overall schematic configuration diagram of an automatic analyzer to which the present invention is applied, and FIG. 1 is a schematic configuration diagram in the vicinity of the sample collection device of FIG. First, the overall configuration of the automatic analyzer will be described with reference to FIG.

In FIG. 10, a sample container 23 containing a biological sample solution such as blood serum or serum is placed on a sample disk 2.
A plurality are arranged on one. These sample containers 23 are removably mounted on the sample disk 21. The rotation of the sample disk 21 is controlled by the computer 3 via the interface 4. The sample disk 21 is rotated in accordance with the order registered in advance so that the sample container 23 is positioned below the pipette nozzle 26 held by the lifting arm 33, and the sample pump connected to the nozzle 26 is rotated. By 32
The sample liquid contained in the sample container 23 is sucked and dispensed into the reaction container 6 in a predetermined amount.

The reaction vessel 6 into which the sample solution has been discharged and dispensed is moved to the first sample addition position in the reaction disk 9 connected to the thermostat 8. Then, the predetermined first reagent sucked from the reagent bottle 12 by the reagent pump 11 connected to the reagent dispensing probe 10 is added to the reaction container 6 moved to the first reagent addition position. After the addition of the first reagent, the reaction vessel 6 is moved to the position of the stirrer 13 and the first stirring is performed.

The light source 1 is placed in the reaction vessel 6 in which the contents are stirred.
The light beam generated from 4 passes through and enters the multi-wavelength photometer 15. Then, the absorbance of the reaction solution, which is the content of the reaction vessel 6, is detected by the multi-wavelength photometer 15. The detected absorbance signal is transmitted to a computer 3 via an analog / digital (A / D) converter 20 and an interface 4.
And converted into the concentration of the analysis item to be measured in the sample liquid.

After the measurement, the reaction vessel 6 is cleaned.
After being moved to the position 9 and the internal liquid is discharged at the washing position 60 by the reaction vessel washing mechanism 19, it is washed with water and used for the next analysis. The measured result is stored in the printer 17
Is printed out or displayed on the CRT screen 18. Which analysis item is measured for one sample depends on
The operator inputs in advance from the keyboard 16 and is stored in the computer 3 via the interface 4 and is controlled by the computer 3 so as to measure the requested analysis item.

Similarly, for a certain analysis item, analysis conditions such as reagent volume, sample volume, measurement wavelength, and reaction time are previously input by the operator from the keyboard 16 as analysis parameters, and are stored in the computer 3 via the interface 4. Have been.

Next, the liquid sample sampling apparatus shown in FIG. 1 applied to the automatic analyzer shown in FIG. 10 will be described.

In FIG. 1, a blood sample or serum sample solution (test solution) is placed on a sample disk 21 made of a non-conductive material.
A sample container 23 in which the sample 22 is accommodated, and electrodes 24 and 25 facing each other with the container 23 interposed therebetween, are arranged.
The pair of electrodes 24 and 25 is
Are arranged in each of a plurality of storage holes for storing the container 23. A pipette nozzle 26 for collecting the sample liquid 22 is inserted into the container 23. The nozzle 26 is formed from a conductive material.

The electrodes 24, 25 and the nozzle 26 are connected to a capacitance measuring section (liquid amount detecting means) 51 of a detecting section 50 for detecting a liquid level and detecting an abnormal suction. The capacitance detection signal from the capacitance measuring section 51 is supplied to the liquid level detecting section 52 and the suction abnormality detecting section (sampling abnormality detecting means) 53 of the detecting section 50. In addition, the liquid level detection unit 5
2 and the output signal from the suction abnormality detection unit 53 are supplied to the computer 3. The nozzle 26 collects the sample liquid 22 in the container 23 by the suction operation of the thin pump sample pump 32 connected via the tube 31. The nozzle 26 is supported by a lifting arm 33. The lift arm 33 is driven by a motor 34 to
5 along the vertical direction indicated by arrow Z. That is, the nozzle 26 is moved up and down relatively to the liquid surface of the sample liquid 22. The motor 34 is controlled based on a control signal from the motor control unit 40. The operations of the motor control unit 40 and the sample pump 32 are controlled by the computer 3.

FIG. 2 is a detailed configuration diagram of the detection unit 50 in FIG.

In FIG. 2, the electrodes 24 and 25 and the nozzle 26 are connected to an AC bridge circuit 27, and the electrode 24 and the nozzle 26 are connected to the zero potential level by grounding. The electrode 25 is connected to the AC potential level. The signal from the AC bridge circuit 27 is supplied to the plus input terminals of subtracters 29 and 30 each composed of a differential amplifier serving as a comparator, via an increasing circuit 28 and an effective value converting circuit 39. The minus input terminal of the subtractor 29
An output signal from the storage unit 43 is supplied, and an output signal from the storage unit 44 is supplied to a minus input terminal of the subtractor 30. These storage units 43 and 44 store the computer 3
The data supplied from is stored.

The output signal of the subtractor 29 is supplied to the liquid level determination section 45.
Is supplied to the computer 3 from the liquid level determination unit 45. The output signal of the subtractor 30 is supplied to the suction abnormality determination unit 46, and the suction abnormality signal from the suction abnormality determination unit 46 is supplied to the computer 3.

The AC bridge circuit 27, the amplifier circuit 28 and the effective value converter 39 constitute a capacitance measuring unit 51. Also, the storage unit 43, the subtractor 29, and the liquid level determination unit 45 constitute a liquid level detection unit 52, and the storage unit 4
4. The suction abnormality detecting unit 53 includes the subtractor 30 and the suction abnormality determining unit 46.

A capacitance _Cx exists between the nozzle 26 and the electrode 24 and the electrode 25. In the capacitance measuring unit 51,
The capacitance _Cx is measured and converted to a voltage.

Next, the operation of one embodiment of the present invention will be described with reference to FIGS. The process is started with no container 23 placed on the sample disk 21. Steps in FIG.
At 100, a command signal from the computer 3 is supplied to the motor 34 via the motor control unit 40 and the nozzle 2
6 is moved to the uppermost position. Next, in step 101, a measurement value based on the magnitude of the capacitance without the container 23 between the electrodes 24 and 25 is detected by the detection unit 50 and stored in the storage unit 43 as the capacitance C0. You. Furthermore, a capacitance value Cy obtained by adding the threshold value C1 to the capacitance C0 (the capacitance when the container 23 contains an appropriate amount of sample liquid and the container 23 is disposed between the electrodes 24 and 25). Is stored in the storage unit 44 from the computer 3.
However, the threshold value C1 is a value corresponding to a state in which an appropriate amount of the sample liquid is stored in the container 23. At this time, the threshold value C1 is a capacitance value in a state where the container 23 is not yet disposed between the electrodes. is there.

That is, the capacitance C _x is measured by the capacitance measuring unit 51, and the initial value (0) stored in the storage unit 43 by the subtractor 29 of the liquid level detecting unit 52 is changed to the capacitance. The _{value is} subtracted from Cx and supplied to the computer 3 via the liquid level determination unit 45. The computer then stores in the storage unit 43 the supplied capacitance value C _x as an electrostatic capacitance value C0, for storing the electrostatic capacitance value Cy in the storage unit 44.

Next, in step 102, a container transport device (not shown) is operated by an instruction from the computer 3 to position the sample container 23 between the electrodes 24 and 25. Then, the capacitance C _x is measured by the capacitance measuring unit 51, and the capacitance value C stored in the storage unit 44 is calculated by the subtractor 30 of the suction abnormality detecting unit 53.
y (= C0 + C1) is subtracted from the capacitance measurements C _x, it is supplied to the suction abnormality determination unit 46. Then, in step 103, the suction abnormality determination unit 46, the capacitance value C _x determines whether small or not than C _y. Capacitance measurement value C
_{If x} is smaller than Cy, the process proceeds to step 104, where the sample container 23 is determined to be empty or the sample liquid amount is equal to or less than a predetermined amount necessary for collection, and the suction abnormality determination unit 46 transmits an abnormality signal to the computer 3. Supply.

[0036] That is, the pre-sucking operation of the sample liquid, the the sample container is required because of the continuing analysis that there is a predetermined amount or more of the sample liquid necessary to harvest by inhalation nozzle 26, C _x If <(C0 + C1), it can be determined that the sample container is empty or the sample liquid is equal to or less than a predetermined amount.
When the sample liquid 22 is present more than a predetermined amount, a signal indicating the value of the capacitance value C _x at that time is supplied from the suction abnormality determination unit 46 to the computer 3. Then, the computer 3 stores the electrostatic capacitance value C _x, the storage unit 44 as the capacitance value Ca of the previous test liquid suction.

Subsequently, a lowering operation of the suction nozzle 26 is performed according to a command signal from the computer 3. In step 105, the nozzle 26 descends until the tip of the nozzle reaches the liquid surface of the sample liquid 22. During this lowering operation, the capacitance measuring unit 51 causes the electrode 24, the electrode 25,
Measured capacitance C _x between the nozzles 26, from the measured capacitance values C _x, by subtracter 29, the capacitance value C0 stored in the storage unit 43 is subtracted. The liquid level determination unit 45 determines whether the subtraction result is greater than the sum of C0 and a predetermined threshold value C2, and the nozzle 26 is lowered until the result is greater. Then, to stop the lowering operation of the nozzle 26 at the time when the direction of C _x becomes large. As a result, the tip of the nozzle 26 stops at a position slightly invading the surface of the sample liquid 22.

That is, before and after the nozzle 26 comes into contact with the liquid surface, the capacitance value C _x changes as shown in FIG. 5, and when the nozzle 26 comes into contact with the liquid surface, the capacitance C _x becomes very sharp. Change.
Therefore, an appropriate threshold value C ₂ is set in advance, and C _x > (C0 + C
When 2) is reached, it can be determined that the tip of the nozzle 26 has contacted the liquid surface. At this time, the liquid level determination unit supplies a liquid level detection signal to the computer 3. When the liquid level detection signal is supplied, the computer 3 stops the lowering operation of the nozzle 26.

In step 106, the computer 3
Causes the sample pump 32 to perform a suction operation, and causes the sample liquid 22 to be sucked into the stopped nozzle 26. Then, Step 1
At 07, the computer operates the motor 34,
The nozzle 26 is lifted away from the liquid level.

Subsequently, in step 108, the capacitance value C _x is measured by the capacitance measuring section 51, and the capacitance value stored in the storage section 44 is calculated from the measured capacitance value C _x. Ca is subtracted by the subtractor 30. Then, either the capacitance C _x is smaller than Ca-Cb, i.e., whether a predetermined amount or more of the sample liquid is aspirated by the nozzle 26 is determined by the suction abnormality determining unit 46. Cb
Is the capacitance value when the minimum amount of liquid sample necessary for suction is stored in the container 23. Therefore,
Ca-Cb represents the capacitance between the electrodes 24 and 25 after a predetermined amount of the sample solution has been sucked.

The sample solution 22, if it is sucked by a predetermined amount or more nozzles _{26, C x ≦ (Ca-} Cb) becomes, in step 109, by the judgment unit 46 a nozzle 26 is normally aspirated sample liquid Is determined. If the sample liquid is not sucked into the nozzle 26 by a predetermined amount or more, C _x >
(Ca−Cb), and in step 110, the suction abnormality determination section 46 determines that the suction is abnormal, and the suction abnormality determination section 46 supplies a suction abnormality signal to the computer 3. In this case, the computer 3 determines that the predetermined amount cannot be suctioned due to some malfunction, stops the sampling of the sample liquid, and displays information indicating “abnormal suction” on an appropriate display means such as the CRT 18; Call attention to the operator.

In this case, when printing the analysis result on a printer, it is also possible to display "abnormal suction" for a sample that could not be suctioned by a predetermined amount.

Next, the change in capacitance when the sample liquid volume changes and when the tip of the nozzle comes into contact with the liquid surface is shown in FIGS.
This will be described with reference to FIG. For the sake of simplicity, in the capacitance equivalent circuit, the shape of the container is a rectangular parallelepiped in both the outer shape and the inner shape, and the shape of the pair of electrodes is a flat plate, which is equal to the shape of the surface of the container in contact.

When a certain amount of sample liquid is present in the sample container 23, it is assumed that the nozzle 26 is located at a sufficiently distant position so as not to affect the electrodes.
6A, the equivalent circuit between the electrodes is as shown in FIG. 6B, and the capacitance value C
_x can be expressed by the following equation (1).

C _x = (C _k ( _Ch + C _m )) / (2 ( _Ch + C _m ) + C _k ) (1) where C _k is the number of electrodes 24 and 2 in the sample container 23.
Capacitance value of the wall portion opposed to the respective 5, C _h is
The capacitance of the air between the electrodes 24 and 25, C _m, is
The capacitance of the sample liquid between the electrodes 24 and 25,
Let ε ₀ and ε _{1 be} the dielectric constants of air and the sample solution, respectively.
A _{C h / ε 0 + C m} / ε 1 = constant).

FIG. 4 shows the relationship between the liquid amount (liquid level) of the test liquid and the capacitance between the electrodes. The vertical axis indicates the capacitance value between the electrodes, and the horizontal axis indicates the liquid level. Height. In FIG. 4, when the liquid amount changes, the capacitance values _Ch and _Cm change, and thus the capacitance between the electrodes changes. That is, the capacitance value increases in proportion to the increase in the liquid level.

As shown in FIG. 7A, the equivalent circuit between the electrodes when the nozzle 26 descends is as shown in FIG. 7B, and the capacitance value _Cx is expressed by the following equation (2). ).

C _x = (C _k ( _Ch + C _m ) (C _k + C _n )) / (C _k ( _Ch + C _m ) + (C _k + C _n ) (C _k + _Ch + C _m )) 2) Here, C _n is a capacitance value of air between the nozzle 26 and the electrode 25.

Here, when the nozzle 26 comes into contact with the liquid surface, C _n → ∞, so that the capacitance value C _x can be expressed by the following equation (3).

C _x = C _k ( _Ch + C _m ) / (C _k + _Ch + C _m ) (3) A graph showing a change in capacitance between the electrodes when the nozzle 26 contacts the liquid surface. 5, the vertical axis represents the capacitance value, and the horizontal axis represents the nozzle descending position. As shown in FIG. 5 and Equations (2) and (3), when the nozzle reaches the sample liquid level, the capacitance value sharply changes greatly. As described above, it is possible to detect that the nozzle 26 has reached the liquid level of the sample liquid by detecting a sudden change in the capacitance value.

Next, the shape of the container and the shape of the electrode which are desirable in carrying out the present invention will be described with reference to FIGS.

From the above equations (1) and (3), the sample container 2
As the capacitance value C _k of the wall surface of the 3 large, large change in capacitance C _x due to the change of the sample fluid volume is large change in capacitance C _x between electrodes before and after contact the liquid surface of the nozzle. That is, it is desirable to make the wall surface of the sample container as thin as possible.

It is desirable that the pair of electrodes sandwiching the sample container be as close as possible to or close to the sample container. Further, from the viewpoint of accurately measuring the change in the amount of the sample liquid, it is desirable that the shape of the electrode is such that the entire sample container is almost covered.

In consideration of the above points, the sample container 23
FIG. 8 shows an example of the shape and dimensions of.

FIG. 8 shows a cross section of the sample container 23. The sample container 23 has a cylindrical shape. The opening 2 has a flange 2 for gripping by a transport device.
3a are formed. The sample container 23 has a height of 25 mm, an inner diameter of 7.4 mm, an outer diameter of 8 mm, and a wall thickness of 0.3 mm. The dimension from the lower surface to the lower end of the flange is 19.7 mm, and the outer diameter of the flange is 10 mm.

FIG. 9 shows the shapes and dimensions of the electrodes 24 and 25. FIG. 9A is a side view, and FIG.
Is an upper surface portion. The electrodes 24 and 25 have a curved shape along the wall of the cylinder so as to cover the cylindrical container. The height of the electrodes 24 and 25 is 20 mm, and the radius of curvature is 4.2 mm. Due to this dimensional relationship, the sample container 23 is inserted between the electrodes so that the sample container 23 rides on the electrodes 24 and 25. The material of the sample container 23 is resinous, and is preferably plastic.

The graphs showing the change in capacitance shown in FIGS. 4 and 5 show the change in capacitance between the electrodes when the sample container and the electrodes shown in FIGS. 8 and 9 are used.

The above-described example is an example in which the present invention is applied to an automatic analyzer. However, the present invention is not limited to the automatic analyzer, but is also applicable to other devices for sampling a liquid sample. It is possible.

Further, in the above-described example, the capacitance value is measured, and the contact of the nozzle with the liquid surface and the suction of a predetermined amount of liquid are determined from the change in the measured capacitance value. However, instead of detecting the capacitance, the amount of electrical change corresponding to the amount of the sample liquid is detected, and contact with the liquid surface of the nozzle and suction of a predetermined amount of liquid are determined from the detected amount of electrical change. It can also be configured.

In addition, the liquid level is detected based on a change in the light transmittance of the light-transmitting container instead of the electrical change amount, and it is determined whether or not a predetermined amount or more of the liquid has been sucked from the container. It is also possible. Furthermore, it is also possible to determine whether or not a predetermined amount or more of liquid is sucked from the container based on a change in the acoustic impedance of the container.

In the above example, the detected capacitance value is compared with a previously stored capacitance value, and when the detected capacitance value becomes larger than the stored capacitance value. In addition, the configuration is such that it is determined that the nozzle has come into contact with the liquid surface.However, the slope of the change in the detected capacitance value is calculated, and when this slope increases sharply, the nozzle moves to the liquid level. It is also possible to configure so as to determine that the contact has been made.

Further, the above-mentioned capacitance values C ₁ and C _1
b is a value when a container having a predetermined shape and material is used. When using the predetermined shape and the container other than the material, using the container, it is sufficient to newly measure the capacitance value C ₁ and C _b storage.

[0063]

According to the present invention, it is possible to determine whether or not a proper amount of the test liquid has been collected by measuring the amount of the test liquid in the container before and after the collection of the test liquid by the suction nozzle. Therefore, it is possible to prevent an abnormal analysis result based on a test liquid sampling error in an automatic analyzer or the like.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a sample collecting device employed in the analyzer of FIG. 10, which is one embodiment of the present invention.

FIG. 2 is a detailed configuration diagram of a detection unit that detects liquid level detection and suction abnormality in the example of FIG.

FIG. 3 is an operation flowchart of the example of FIG. 1;

FIG. 4 shows a sample liquid level of a sample container in the example of FIG.
It is a graph which shows the relationship with a capacitance value.

FIG. 5 is a graph showing a relationship between a nozzle lowering position with respect to a liquid level in a sample container and a capacitance value in the example of FIG. 1;

FIG. 6 is an equivalent circuit diagram of a sample container sandwiched between electrodes when a suction nozzle is at an uppermost position.

FIG. 7 is an equivalent circuit diagram of a sample container sandwiched between electrodes when the nozzle is lowered.

8 is a diagram showing an example of a sample container used in the example of FIG.

FIG. 9 is a diagram illustrating an example of an electrode used in the example of FIG. 1;

FIG. 10 is a schematic configuration diagram of an automatic analyzer to which the present invention is applied.

[Explanation of symbols]

3 ... computer, 6 ... reaction container, 10 ... reagent dispensing probe, 11 ... reagent pump, 12 ... reagent bottle, 15 ... multi-wavelength photometer, 21 ... sample disk, 22 ... sample liquid,
23: sample container, 24, 25: electrode, 26: nozzle, 2
7 bridge circuit, 29, 30 subtractor, 32 sample pump, 33 lifting arm, 40 motor controller, 4
3, 44: storage unit, 45: liquid level determination unit, 46: suction abnormality determination unit, 50: detection unit, 51: capacitance measurement unit, 52:
Liquid level detector, 53 ... suction abnormality detector.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-295764 (JP, A) JP-A-2-151727 (JP, A) JP-A-63-304119 (JP, A) (58) Survey Field (Int.Cl. ⁷ , DB name) G01N 35/10 G01F 23/26

Claims (6)

(57) [Claims] 1. A liquid sampling method for sampling a test liquid contained in a container using a suction nozzle, comprising: a liquid level detecting means for detecting a liquid level of the test liquid in the container; A liquid amount detecting means for measuring the liquid amount of the test liquid, and when the suction nozzle is lowered to collect the test liquid, the suction nozzle is turned on by the liquid level detecting means. Measuring the time of contact with the liquid surface of the sample, measuring the liquid amount of the test liquid at the time of the contact by the liquid amount detecting means, and furthermore, when collecting the test liquid, raising the suction nozzle. Measuring the time when the suction nozzle is separated from the liquid surface of the test liquid by the liquid level detecting means, measuring the liquid amount of the test liquid at the separated time point by the liquid amount detecting means, Based on the difference in the amount of the test liquid before and after collection of the test liquid measured by the amount detection means, Liquid collecting method characterized by determining whether a predetermined amount of the test liquid was taken by serial inhalation nozzle. 2. The liquid sampling method according to claim 1, wherein a liquid level detecting means for detecting a liquid level of the test liquid in the container, and a liquid amount detecting means for measuring a liquid amount of the test liquid in the container. Is a means for measuring using a change in capacitance. 3. The liquid collection method according to claim 1, wherein the liquid level detecting means for detecting the liquid level of the test liquid in the container is means for measuring using a change in capacitance, A liquid amount detecting means for measuring the liquid amount of the test liquid in the,
Means for measuring using a measured value of the liquid level of the test liquid. Based on a difference in the liquid amount of the test liquid before and after the collection of the test liquid, a predetermined amount is measured by the suction nozzle. Determining whether or not the test liquid is collected. 4. A liquid collecting apparatus provided with a vertically movable suction nozzle for collecting a test liquid contained in a container, wherein a liquid level detecting means for detecting a liquid level of the test liquid in the container; A liquid amount detecting means for measuring the liquid amount of the test liquid in the container; and the liquid amount of the test liquid at the time when the suction nozzle contacts the liquid surface of the test liquid by the liquid level detecting means. Means for measuring by the detecting means and storing the measurement result; and when raising the suction nozzle after collecting the test liquid, the liquid level detecting means separates the suction nozzle from the liquid level of the test liquid. Means for measuring the liquid volume of the test liquid at the time of the detection by the liquid amount detecting means, and storing the measurement result; and the liquid of the test liquid before and after collection of the test liquid stored by the storage means. And a comparing means for comparing the amount of the test liquid based on the comparison result. Liquid collecting device comprising a judging device for judging whether or not taken from the vessel, further comprising a. 5. A liquid collecting apparatus having a vertically movable suction nozzle for collecting a test liquid contained in a container, comprising: a first electrode and a second electrode which are opposed to each other so as to sandwich the container. A capacitance between the first electrode and the second electrode; and a capacitance between the suction nozzle and the first electrode or the second electrode, wherein the suction nozzle is made of a conductive material. And a capacitance measuring circuit for detecting the time when the suction nozzle comes into contact with the liquid surface of the test liquid by the capacitance measuring circuit, and further, the suction nozzle by the capacitance measuring circuit. Measures the capacitance corresponding to the liquid volume of the test liquid at the time when it contacts the liquid surface of the test liquid,
The storage means for storing the measurement results, and the capacitance measurement circuit detects the point at which the suction nozzle separates from the liquid surface of the test liquid, and further detects the suction nozzle by the capacitance measurement circuit. A storage means for measuring the capacitance corresponding to the liquid volume of the test liquid at a point away from the liquid surface of the liquid and storing the measurement result, and before and after collection of the test liquid stored by the storage means Comparing means for comparing the capacitance corresponding to the amount of the test liquid in the test liquid, and determining means for determining whether or not a predetermined amount of the test liquid has been collected from the container based on the comparison result. , A liquid collection device comprising: 6. The liquid sampling apparatus according to claim 5, wherein the container-absent capacitance when the container is not disposed between the first electrode and the second electrode is measured by the capacitance measuring circuit. Then, based on the comparison result between the measured value of the container-absent capacitance and the measured value of the capacitance before collection, it is determined whether or not the test liquid in an amount equal to or more than that required for collection is contained in the container. A liquid collecting apparatus characterized by making a determination by the determination means.