JPH09189704A - Automatic chemical analyzer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic chemical analyzer which has a long service life and can be used for high-accuracy analysis by detecting the arrival of a reagent with a liquid level sensor provided in the middle of a reagent tube and supplying a gas to the reagent tube from an air supplying section provided in the middle of the tube in response to the signal of the sensor. SOLUTION: A reaction nozzle 34 is connected to a reagent tank 30 provided with a reagent pump 40 through a reagent tube 35 and an air valve 42 and a liquid level sensor 43 are provided in the middle of the tube 35. The valve 42 is connected to a compressor 41 through an air tube 45. Firstly, the reagent 27 is sent from the pump 40 by closing the valve 61 and, when the sensor 43 detects the surface level of a reagent ascending beyond the level of the sensor 43, the pump 40 is rotated in the opposite direction at a low speed. When the surface level of the reagent descends to the level of the sensor 43, the valve 61 is opened. The reagent 27 on the exit side of a branch section 36 is supplied to a photometric cell by jetting the reagent 27 from the nozzle 34 by blowing pressurized air into the branch section 36 from an air chamber 62 through an air tube. The pressurized air is continuously blown until the reagent remaining in the nozzle 34 is completely discharged. Therefore, high-accuracy analysis can be performed.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an automatic chemical analyzer for reacting a sample with a reagent and measuring the concentration of a specific component in the reaction solution.

[0002]

2. Description of the Related Art Discrete-type automated chemistry in which human serum or the like is used as a sample, a desired reagent is reacted with the sample, and the concentration of a specific component in the reaction solution is measured by a colorimetric method for diagnosis. Analytical devices are known.

In a conventional discrete type automatic chemical analyzer, a plurality of photometric cells 12 are arranged on a circular turntable 11 as shown in FIG. 5 as disclosed in Japanese Patent Laid-Open No. 3-65654, and the turntable 11 is arranged. A spectroscopic measurement device 13, a cleaning device 14, a sample pipetter 21, and a reagent nozzle 34 are arranged in close proximity to the. A sample container 22 and a cleaning device 23 are arranged in the operation range of the sample pipetter 21. The syringe valve 31 and the reagent tank 30 are connected to the switching valve 32 connected to the reagent nozzle 34 by a driving liquid tube 33 and a reagent tube 35, respectively.

In this apparatus, a fixed amount of the sample in the sample container 22 is sucked by the sample pipettor 21 and dispensed into one of the photometric cells 12 in a fixed amount. A certain amount of reagent is dispensed from the reagent tank 30 to the photometric cell 12 through the reagent nozzle 34. When the sample and the reagent are mixed and reacted in the photometric cell 12, a color change corresponding to the concentration of the specific chemical component in the sample occurs depending on the type of the reagent. The turntable 11 rotates, and the spectrophotometer 13 measures the absorbance of the mixture of the sample and the reagent in the photometric cell 12. The turntable 11 is further rotated, the interior of the photometric cell 12 is cleaned by the cleaning device 14, and the mixed liquid is discharged. The tip of the sample pipetter 21 is cleaned by the cleaning device 23, and subsequently the next sample is analyzed. The measurement information of the spectroscopic measurement device 13 is calculated in the analyzer 10 and output as the information of the concentration of the chemical component.

In this case, the dispensing of the reagent is performed as follows. First, the switching valve 32 includes the driving liquid tube 33.
And the reagent tube 35 are brought into communication with each other, and a certain amount is sucked by the syringe pump 31. Since the driving liquid tube 33 is filled with the driving liquid, the reagent is sucked into the driving liquid tube 33 through the reagent tube 35. Next, the switching valve 32 is switched to bring the driving liquid tube 33 and the reagent nozzle 34 into communication with each other. When a certain amount of the syringe pump 31 is discharged in this state, the reagent stored in the driving liquid tube 33 is pushed out by the driving liquid and is discharged from the reagent nozzle 34 by a certain amount. Thus, a fixed amount of reagent is accurately dispensed from the reagent nozzle 34 to the photometric cell 12.

According to this conventional apparatus, a fixed amount of reagent and a sample can be accurately mixed and continuously measured, so that a specific component contained in the sample can be accurately and continuously analyzed. Further, since the required amount of reagent is sucked and discharged in one measurement, the reagent is not wasted and the reagent consumption amount is small.

[0007]

In the conventional apparatus, since the reagent is dispensed using the driving liquid, the driving liquid and the reagent are mixed with each other, so that an error occurs in the amount of the reagent dispensed into the photometric cell, and the analysis is performed. Caused a decrease in the accuracy of. Further, since the reagent mixed in the driving liquid diffuses in the tube and reaches the syringe pump 31, there is a problem that the interior of the syringe pump 31 is attacked and the life of the device is shortened.

It is an object of the present invention to provide an automatic analyzer having a reagent dispensing system which has a long life and enables highly accurate analysis.

[0009]

In order to solve the above problems, according to the present invention, a reagent dispensing system for dispensing a fixed amount of a reagent from a reagent container to a photometric cell and a fixed amount of a sample to be measured are provided in the photometric cell. A sample dispensing system for dispensing to a sample, a transport system that transports the photometric cell at a constant speed and repeats a stopped state, and a detection system that is installed at a specific location of the transport system and measures the properties of the liquid in the photometric cell. In an automatic chemical analyzer equipped with a cleaning system that is installed in a specific location of the transport system to clean the inside of the photometric cell and an analyzer that analyzes the output signal of the detection system, the reagent dispensing system is the position of the photometric cell from the reagent container. Including continuous reagent piping up to
It has a liquid level sensor that detects the arrival of the reagent in the middle of the reagent pipe, an air supply part is provided in the middle of the reagent pipe, and a function to insert gas from the air supply part into the reagent pipe in response to the liquid level sensor signal. It has a structure with.

Further, a reversible reagent pump is provided in the middle of the reagent pipe, the reagent pump is reversed after the reagent has passed through the liquid level sensor, and when the reagent again passes through the liquid level sensor, the air supply unit The gas was inserted into the reagent. In addition, the inner surface of the reagent pipe downstream of the air supply portion is made water repellent.

[0011]

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

FIG. 1 is a perspective view of the first embodiment of the present invention. On the turntable 11 on the analyzer 10, a plurality of photometric cells 12 are arranged along the circumferential direction. Around the turntable 11, a cleaner 14 and a spectrophotometer 1
3, a sample pipettor 21, and a reagent nozzle 34 are arranged.

A reagent tube 30 is connected to the reagent nozzle 34 by a reagent tube 35, and an air valve 42 and a liquid level sensor 43 are arranged in the path of the reagent tube 35. Further, the air valve 42 is connected to the compressor 41 by an air tube 45. Also, the reagent tank 30
Is equipped with a reagent pump 40. Several of these systems are lined up. The reagent tank 30 is cooled.

The sample pipettor 21 is rotatable up and down,
A sample transporter 24 and a cleaning device 23 are installed on the radius of gyration. A plurality of sample containers 22 can be set in the sample transporter 24.

The analyzer 10 is also provided with a display unit 15, operation buttons 16 and an output unit 17.

The first embodiment operates as follows. First, a plurality of samples to be measured are put in the sample container 22, set in the sample transporter 24, and set in the analyzer 10. When the operation button 16 is pressed to start the operation, the sample container 22 moves to a predetermined position, the sample pipetter 21 descends into the sample container 22 containing the first sample, and a certain amount of sample is sucked up and rotated. Then, the sample is discharged to one of the photometric cells 12. The sample pipette 21 is moved to the position of the washer 23 and washed.

The turntable 11 rotates, the photometric cell 12 containing the sample reaches the position of the reagent nozzle 34, and a certain amount of reagent is supplied from the reagent nozzle 34. The reagent and the sample are mixed and reacted with each other, reach the position of the spectroscopic measuring device 13 after a predetermined time, and optical analysis is performed. The result of obtaining the concentration of the specific component in the sample by the optical analysis is displayed on the display unit 15 and output from the output unit 17.

The photometric cell 12 further advances to the position of the washer 14, and the contents are sucked and washed.

The sample carrier 24 moves to analyze a plurality of samples. In addition, analysis of multiple items is performed in parallel using multiple types of reagents.

FIG. 2 is a structural diagram of the reagent supply system of the first embodiment. The liquid level sensor 43 is paired with the light source 44 and can detect passage of the reagent in the reagent nozzle 34 on the liquid level. The inner surface of the reagent nozzle 34 is subjected to water repellent treatment. A level detection circuit 50, a logic circuit 51, and a driver 52 are connected to the liquid level sensor 43, and the driver 52 is connected to an actuator 60 and a reagent pump 40. The air valve 42 includes an air chamber 62, an actuator 60, a valve 6
1, the ventilation pipe 63, the compressed air supplied from the compressor 41 is stored in the air chamber 62, and the discharge is controlled by the operation of the actuator 60. Reagent pump 4
0 is in this case an ironing pump, which is able to feed in the forward and reverse directions.

The reagent tube 35 from the branch portion 36 to the liquid level sensor 43 has an inner diameter of 1.5 mm and a length of 38 m.
m. Therefore, the volume between them is 30 microliters. The ventilation pipe 63 has an inner diameter of 1 mm and a length of 10 mm.
It is. The volume of the air chamber 62 is 100 microliters.

FIG. 3 is a diagram for explaining the operation of the reagent supply system of the first embodiment. (A) First, the reagent 27 is delivered from the reagent pump 40 with the valve 61 closed. (B) When the liquid level sensor 43 detects the passage of the reagent surface, the reagent pump 40 is rotated in the reverse direction. The reagent feed rate at this time is smaller than the forward feed rate. (C) Again, the reagent level is the level sensor 43.
When the position is reached, the valve 61 is opened. Air chamber 62
Air pressurized from is passed through the ventilation pipe 63 and inserted from the branch portion 36. (D) The reagent 27 at the portion on the outlet side of the branch portion 36 is ejected from the reagent nozzle 34, and the photometric cell 1
2 is supplied. (E) The pressurized air is discharged until all the liquid droplets remaining inside the reagent nozzle 34 are discharged.

When stopping the operation of the apparatus, the reagent pump 40 is rotated in the reverse direction so that the reagent remaining in the reagent tube 35 is returned to the reagent tank 30.

When the reagent in the reagent tank 30 is used up, the reagent tank 30 and the reagent pump 40 are replaced with a new one.

In the case of the first embodiment, since no other liquid intervenes in the reagent channel, there is no thinning of the reagent and the reagent can be used without waste. Further, the liquid level of the reagent is detected at a portion near the tip of the reagent nozzle 34, and the reagent is ejected by the signal, so that the liquid level sensor 4 must always be discharged from the reagent nozzle 34.
The reagent of a constant volume up to the position of 3 is discharged, and the accuracy of the discharge volume is high. In addition, since the length from the branch portion 36 to the tip of the nozzle is short, the wetted area of the inner surface is small, and the pressurized air is sufficiently ejected, the reagent remains as a droplet on the inner surface, which causes an error in ejection volume. Is small. Particularly, in this embodiment, since the water repellent treatment is applied to the inner surface of the nozzle, the amount of wetting on the inner surface is extremely small.

Further, in the case of this embodiment, since the valve 61 does not come into contact with the reagent, it is not attacked by the reagent and has a long life.

Further, in FIG. 3A, the air portion interposed in the ventilation pipe 63 is compressed, but in FIG. 3B it is expanded because the reagent is sucked, and in FIG. The amount of the reagent existing in the ventilation pipe 63 at the moment of opening is small, and the influence on the reagent dispensing volume is small.

Further, in the case of this embodiment, the reagent tank 30
And a reagent nozzle 34 are separated from each other by a reagent tube 35, and a reagent tank 30 and a reagent pump 40 having a large volume are provided.
Since it can be installed at a position away from the reagent nozzle 34, it is possible to arrange a plurality of reagent nozzles 34 on the photometric cell 12 in close proximity and to supply a plurality of reagents at the same time. Although only two reagent systems are shown in FIG. 1, about 10 to 20 kinds of reagents are actually used. As many reagent nozzles 34 as the number of types of reagents are used for the photometric cell 1.
2 on which the necessary reagents are selectively supplied. Further, at this time, since the reagent tank 30 having a capacity of 100 ml or more is typically used, in order to arrange 10 or more of them, the reagent tube 35 having a long length is 300 mm.
To more than 1000mm.

When the reagent tube 35 has a length of 300 mm or more, there is a delay in the operation of the reagent pump 40 to transmit the movement of the reagent. In this embodiment, however, there is a delay between the liquid level sensor 43 and the reagent nozzle 34. Because there is a small space in
The liquid level sensor 43 detects the passage of the reagent liquid level, and the reagent pump 4
The amount of the reagent that passes by the time when the reagent is actually rotated in the reverse direction after being stopped at 0 and rotated in the reverse direction does not come out of the reagent nozzle 34. Further, when the passage of the reagent is detected again by the liquid level sensor 43 and the valve 61 is opened, the distance from the valve 61 to the reagent nozzle 34 is short and the reagent is ejected without delay time. It never happens.

Further, in the case of this embodiment, the reagent pump 4
Since 0 is not strict in quantification accuracy, it can be a low-priced one.

Further, in the case of this embodiment, when the apparatus is stopped, the reagent is returned to the inside of the reagent tank 30 where it is cooled, so that the reagent is not deteriorated and the reagent is not wasted. Further, since it is not necessary to cool the periphery of the reagent tube 35, a large cooling device is not required, and the device can be downsized.

Further, in the case of this embodiment, since the reagent tank 30 and the reagent pump 40 are exchanged as a set, the time required for the exchange can be shortened. Further, even if the reagent pump 40 is deteriorated by the reagent, the reagent pump 40 is replaced at an appropriate interval, so that the reliability of the device for a long period of time is maintained.

Further, in the case of this embodiment, the volume of the air chamber 62 is several times the volume of the reagent to be discharged at one time, and therefore the air chamber 62 is opened when the valve 61 is opened.
A sufficient amount of compressed air inside is discharged in a short time,
The reagent including the reagent attached to the inner wall surface can be quickly discharged, and the time required for analysis can be shortened.

In this embodiment, the liquid level sensor 43 may be electrochemical rather than optical. Also,
Instead of the compressor 41, a gas source such as a gas cylinder may be used.

The reagent pump 40 may be a bellows pump as shown in FIG. 5, instead of the ironing pump. In this case, the reagent pump 40b is composed of a bellows 47, an actuator 46, and a valve 48, and the operation of the actuator 46 delivers the reagent from the reagent tube 35.
Suction is possible.

In this case, the actuator 46 is fixed to the apparatus main body, and when the reagent tank 30 is replaced, the actuator 46 is left and replaced. Since the actuator 46 and the bellows 47 are simply in contact with each other,
Can be replaced quickly.

[0037]

According to the present invention, since the reagent is dispensed without using the driving liquid, the driving liquid and the reagent are mixed with each other, so that an error does not occur in the amount of the reagent dispensed into the photometric cell and the accuracy is improved. High analysis is possible. Since the reagent does not directly touch the valve, the life of the device can be extended. Therefore, it is possible to provide an automatic analyzer having a reagent dispensing system that has a long life and enables highly accurate analysis.

[Brief description of the drawings]

FIG. 1 is a perspective view of an automatic chemical analyzer according to a first embodiment.

FIG. 2 is a block diagram of a reagent supply system according to the first embodiment.

FIG. 3 is an explanatory diagram of an operation of the first embodiment.

FIG. 4 is an explanatory diagram of a reagent pump according to a second embodiment.

FIG. 5 is a perspective view of a conventional automatic analyzer.

[Explanation of symbols]

10 ... Analysis device, 11 ... Turntable, 12 ... Photometric cell, 13 ... Spectrometer, 14, 23 ... Washer, 15 ... Indicator, 16 ... Operation button, 17 ... Output device, 21 ... Sample pipettor , 22 ... sample container, 24 ... sample transporter, 30 ... reagent tank, 34 ... reagent nozzle, 35 ... reagent tube, 4
0 ... Reagent pump, 41 ... Compressor, 42 ... Air valve, 43 ... Liquid level sensor, 45 ... Air tube.

Claims (4)

[Claims] 1. A reagent dispensing system for dispensing a fixed amount of a reagent from a reagent container to a photometric cell, a sample dispensing system for dispensing a fixed amount of a sample to be measured to the photometric cell, and a constant speed of the photometric cell. Transport by
A transport system that repeats the stopped state, a detection system that is installed at a specific location of the transport system to measure the properties of the liquid in the photometric cell, and a cleaning system that is installed at a specific location of the transport system to clean the interior of the photometric cell, In an automatic chemical analyzer equipped with an analyzer that analyzes an output signal of a detection system, the reagent dispensing system includes a continuous reagent pipe from the reagent container to a position of a photometric cell, and a reagent reaches the middle of the reagent pipe. A liquid level sensor for detecting a liquid level sensor, an air supply unit is provided in the middle of the reagent pipe, and has a function of inserting gas from the air supply unit into the reagent pipe in response to a liquid level sensor signal. Automatic chemical analyzer. 2. The reagent pump according to claim 1, wherein a reversible reagent pump is provided in the middle of the reagent pipe, the reagent pump is reversed after the reagent has passed through the liquid level sensor, and the reagent has passed through the liquid level sensor again. An automatic chemical analyzer that inserts gas from the air supply unit into the reagent at the timing. 3. The automatic chemical analyzer according to claim 1, wherein the inner surface of the reagent pipe downstream of the air supply portion is water repellent. 4. A reagent dispensing system for dispensing a fixed amount of a reagent from a reagent container to a photometric cell, a sample dispensing system for dispensing a fixed amount of a sample to be measured to the photometric cell, and a constant speed of the photometric cell. Transport by
A transport system that repeats a stopped state, a detection system that is installed at a specific location of the transport system to measure the properties of the liquid in the photometric cell, and a cleaning system that is installed at a specific location of the transport system to clean the interior of the photometric cell And an automatic chemical analyzer provided with an analyzer for analyzing the output signal of the detection system, wherein the reagent dispensing system includes a reagent pipe of 300 mm or more, and has a reagent container and a reagent pump mechanism on one side of the reagent pipe, On the other hand, it has a reagent nozzle, a liquid volume measurement system, and a liquid separation mechanism, and has the function of controlling the operation of the pump mechanism and the liquid separation mechanism based on the signals of the liquid volume measurement system. Automatic chemical analyzer that does not intervene.