JP2015215274A - Automatic analysis device and analysis method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic analysis device in which the destabilization of electric potential due to that bubbles absorbed in order to prevent the contamination of a next sample by dripping from a suction nozzle or a previous sample touch a sensitive membrane is reduced, and the stability of measured values is improved.SOLUTION: The automatic analysis device comprises a flow-type sensor unit 211, a nozzle 201 for absorbing a liquid or gas, a first channel 202 for connecting the nozzle and the sensor unit, a second channel 203 for connecting the sensor unit and a pump, and a third channel 204 branched from an upstream section closer to the nozzle than is the sensor unit and connected to the pump or the second channel, and further includes a control unit for switching between a first suction operation for introducing the liquid or gas absorbed from the nozzle into the flow-type sensor via the first channel, a second suction operation for absorbing bubbles into the nozzle tip, and a third suction operation for absorbing bubbles into the pump via the third channel, the bubbles generated inside the channel by the second suction operation being removed by the third suction operation before the first suction operation.

Description

The present invention relates to an automatic analyzer and an analysis method for performing component analysis of a liquid sample.

  A flow-type analyzer including a flow-type detector is used in a wide range of fields such as clinical inspection of biological samples and inspection of plant production processes because it can continuously and repeatedly measure a plurality of samples. In particular, in a biochemical automatic analyzer used for clinical examinations of biological samples such as blood and urine, an ion selective electrode (hereinafter referred to as ISE; Ion) is used as a technique for analyzing electrolytes (Na ions, K ions, Cl ions, etc.). The ion selective electrode method using Selective Electrode is the mainstream.

  In the ion selective electrode method, an electrolyte concentration in a sample is measured by measuring a potential difference (electromotive force) between the reference electrode and the ISE using an ion-sensitive membrane whose potential varies according to the electrolyte concentration. In order to measure the potential difference, it is necessary that the ISE and the reference electrode are electrically connected through the specimen. In addition, it is necessary to be isolated from an electrical noise source for accurate potential difference measurement.

In a flow-type electrolyte analyzer, a specimen is sucked from a container containing the specimen with a suction nozzle and introduced into an ISE that is a sensor unit to measure an electrolyte concentration. In some cases, an internal standard solution for performing one-point correction between sample measurements is measured. Patent document 1 is mentioned as a well-known example which shows the flow-path structure of such an electrolyte analyzer.

JP 2013-24799 A

  In the flow-type electrolyte analyzer as described in Patent Literature 1, after the first sample (sample A) is sucked with the suction nozzle, the next sample (sample B) is sucked from the tip of the nozzle. The purpose is to prevent dripping of the previous sample or the previous sample introduced into the nozzle tip from contacting the next sample and contaminating the sample. It is common. The sucked air moves together with the sample in the form of an air layer (air gap) generated between the sample A and the sample B in the flow path.

When an air gap enters between samples, there are the following problems. (1) Due to the characteristics of ISE, if the ion sensitive membrane is exposed to the air during solution measurement, it takes time to stabilize the potential during sample measurement, and therefore it is difficult to increase the analysis speed. (2) If bubbles remain in the flow path during potential measurement, electrical noise may occur.

  The configuration of the present invention for solving the above problems is as follows.

That is, a sensor unit that measures a component contained in the liquid, a nozzle that sucks the gas and the liquid contained in the container, a first flow path that connects the nozzle and the sensor unit, and the sensor unit and the pump are connected. A second flow path, a third flow path branched from the first flow path and connected to the second flow path or the pump, and a fluid sucked by the nozzle for the first flow path or the second flow A switching unit for switching to which path to introduce, and the switching unit for introducing the liquid sucked from the nozzle into the first flow path and introducing the gas sucked from the nozzle into the third flow path. And a control hand part for controlling.

According to the present embodiment, the potential instability due to the aspirated bubbles coming into contact with the sensitive membrane is reduced in order to prevent dripping of the suction nozzle and contamination of the next sample by the previous sample, and the stability of the measured value. Will improve. Moreover, since the risk that bubbles remain in the flow path between the ISE and the reference electrode and electrical noise is generated can be reduced, the reliability of the measurement result is improved.

It is an example of the automatic analyzer of this invention. It is a flow-path block diagram of the conventional electrolyte measurement part. It is a figure explaining operation | movement of the conventional electrolyte measurement part. It is an operation | movement flowchart of the conventional electrolyte measurement part. It is a flow-path block diagram of the electrolyte measurement part in this invention. (Example 1) It is a figure explaining operation | movement of the electrolyte measurement part in this invention. (Example 1) It is a figure explaining operation | movement of the electrolyte measurement part in this invention. (Example 1) It is an operation | movement flowchart of the electrolyte measurement part in this invention. (Example 1) It is a figure which shows an example of the flow-path structure of the electrolyte measurement part in this invention. (Example 2) It is a flow-path block diagram of the electrolyte measurement part in this invention. (Example 3) It is an operation | movement flowchart of the electrolyte measurement part in this invention. (Example 3)

<Configuration of automatic analyzer>
Hereinafter, examples will be described with reference to the drawings.

The overall configuration and operation of the automatic analyzer according to the present embodiment will be described with reference to FIG. FIG. 1 is a schematic configuration diagram showing an example of the overall configuration of the automatic analyzer. Here, a biochemical automatic analyzer will be described as an example.
In FIG. 1, 1 is a sample disk, 2 is a reagent disk, 3 is a reaction disk, 4 is a reaction tank, 5 is a sampling mechanism, 6 is a reagent dispensing mechanism, 7 is a stirring mechanism, 8 is a photometric mechanism, and 9 is a cleaning mechanism. 10 is a computer (PC), 11 is an electrolyte measurement unit, 12 is a storage device, 13 is a control unit, 14 is a piezoelectric element driver, 15 is a stirring mechanism controller, 16 is a sample container, 17 is a circular sample disk, and 18 is a reagent. Bottle, 19 is a circular reagent disk, 20 is a cold storage, 21 is a reaction vessel, 22 is a reaction vessel holder, 23 is a drive mechanism, 24 is a sample probe, 25 is a sample probe support shaft, 26 is a sample probe arm, 27 is a reagent Probe, 28 is a reagent probe support shaft, 29 is a reagent probe arm, 30 is a sampling mechanism for electrolyte measurement, 31 is a fixed part, and 33 is a nose , The vertical drive mechanism 34, 35 is the electrolyte measurement sample probe, 36 sample probe support shaft for electrolyte measurement, 37 is a sample probe arm electrolyte measurement.
The automatic analyzer according to the present embodiment mainly includes a sample disk 1 on which a plurality of sample containers 16 are placed, a reagent disk 2 on which a plurality of reagent bottles 18 are placed, and a plurality of reaction containers 21. A reaction disk 3 to be placed; a sampling mechanism 5 installed in the vicinity of the sample disk 1 and the reaction disk 3; a reagent dispensing mechanism 6 installed in the vicinity of the reagent disk 2 and the reaction disk 3; A stirring mechanism 7, a photometric mechanism 8, a cleaning mechanism 9, an electrolyte measuring unit 11, an electrolyte measuring sampling mechanism 30, and the like installed in the vicinity of the disk 3 are configured.
In the sample disk 1, a plurality of sample containers 16 for storing a sample to be analyzed (also referred to as a sample) are placed on a circular sample disk 17 side by side on the circumference. A sampling mechanism 5 is installed in the vicinity of the sample disk 1. The sampling mechanism 5 is attached to a sample probe arm 26 fixed to a sample probe support shaft 25, in which a sample probe 24 sucks a sample from the corresponding sample container 16 and discharges the sample to the corresponding reaction container 21. .
In the reagent disk 2, a plurality of reagent bottles 18 for storing reagents are placed side by side on a circle on a circular reagent disk 19. The reagent disk 2 is provided with a cool box 20. A reagent dispensing mechanism 6 is installed in the vicinity of the reagent disk 2. The reagent dispensing mechanism 6 is attached to a reagent probe arm 29 fixed to a reagent probe support shaft 28. The reagent probe 27 sucks a reagent from the corresponding reagent bottle 18 and discharges the reagent to the corresponding reaction container 21. ing.
A plurality of reaction vessel holders 22 holding a plurality of reaction vessels 21 are placed side by side on the circumference of the reaction disk 3. A reaction tank 4 is installed on the reaction disk 3. The reaction disk 3 can be intermittently rotated by the drive mechanism 23. In the vicinity of the reaction disk 3, a stirring mechanism 7, a photometric mechanism 8, a cleaning mechanism 9, an electrolyte measuring unit 11, an electrolyte measuring sampling mechanism 30, and the like are installed.
The stirring mechanism 7 is a mechanism for stirring the contents (sample and reagent) in the reaction vessel 21, and includes a piezoelectric element driver 14, a stirring mechanism controller 15, and the like. The photometric mechanism 8 is a mechanism for measuring transmitted light that has been transmitted through the contents in the reaction vessel 21 and scattered light that has been scattered by the contents, and includes a light source, a detector, and the like (not shown). The cleaning mechanism 9 is a mechanism for cleaning the inside of the reaction vessel 21 and includes a nozzle 33, a vertical drive mechanism 34, and the like.
The electrolyte measurement unit 11 is an apparatus for measuring an electrolyte of a sample, and includes an ion selection electrode, a comparison electrode, and the like. The electrolyte measurement sampling mechanism 30 is a mechanism for dispensing a sample to the electrolyte measurement unit 11. The electrolyte measurement sample probe 35 for inhaling the sample is fixed to the electrolyte measurement sample probe support shaft 36. A sample probe arm 37 is attached.

<Conventional electrolyte measuring device>
FIG. 2 is a diagram showing a flow path configuration of a conventional electrolyte measurement unit.

  The suction nozzle unit 201 is connected to the ISE electrode 211 through an ISE flow path 202 made of a resin tube or the like. The ISE electrode 211 is connected to three ISE electrodes having electrode films for measuring the ion concentration of Na, K, and Cl, and the liquid sucked by the suction nozzle unit 201 communicates with the ISE channel 202. Are introduced into each ISE electrode.

  Vertical movement drive means (not shown) such as a motor is provided so that the suction nozzle unit 201 can be moved up and down at a programmed timing. At the time of sample suction, the suction nozzle portion 201 is lowered, the tip of the nozzle is lowered into the sample in the sample container 213, and the syringe pump 210 is driven to introduce the sample into the ISE channel 202. Air can be introduced into the flow path by driving the syringe pump 210 with the suction nozzle portion 201 raised and the tip of the nozzle separated from the sample container 213.

  The comparison electrode bottle 14 containing the comparison electrode solution is connected to the REF electrode 212 through the REF flow path 3.

  The ISE flow path 202 and the REF flow path 203 are connected by a liquid junction 217 and are connected to a waste liquid container 215 via a syringe pump 210.

  A pinch valve 209 is provided between the ISE electrode 211 and the liquid junction 217 in the ISE flow path 2, an electromagnetic valve 206 is provided between the comparison electrode bottle 14 and the REF electrode 212 in the REF flow path 203, and the liquid junction 217 and the syringe. An electromagnetic valve 205 is provided between the pumps 210, and an electromagnetic valve 207 is provided between the syringe pump 210 and the waste liquid container 215. Each electromagnetic valve and pinch valve can be opened and closed at a timing programmed by the control computer, and the flow of the liquid in the flow path can be controlled by synchronizing with the suction and discharge operations of the syringe pump 210.

  The basic operation of the conventional electrolyte measurement unit is composed of (a) ISE unit filling operation, (b) reference electrode unit filling operation, and (c) discharging operation. The basic operation will be described below with reference to FIG.

  FIG. 3A is a flow chart showing the ISE portion filling operation, in which the pinch valve 209 and the electromagnetic valve 205 are opened, and the electromagnetic valve 206 and the electromagnetic valve 207 are closed. In this state, when the plunger of the syringe pump 210 is pulled to perform a suction operation, the sample or air is sucked from the tip of the suction nozzle unit 201 through the ISE flow path 202, the ISE electrode 211, and the liquid junction 217 to the syringe pump. . The sample is sucked by driving the syringe pump in a state where the suction nozzle unit 201 is lowered below the liquid level in the sample container (a state where the nozzle tip is introduced into the sample liquid). Air is sucked by driving the syringe pump in a state where the tip is raised above the liquid level (a state where the nozzle tip is separated from the sample liquid level). The sucked sample and air are filled into the ISE electrode 211 via the ISE flow path 202. The sample and air that have passed through the ISE electrode 211 are introduced to the waste liquid flow path 220 side.

  FIG. 3B is a flow chart showing the filling operation of the reference electrode part. The electromagnetic valves 205 and 206 are opened, and the electromagnetic valve 207 and the pinch valve 209 are closed. When the suction operation is performed by pulling the plunger of the syringe pump in this state, the comparison electrode liquid is sequentially filled from the comparison electrode liquid bottle 214 to the REF flow path 203 and the comparison electrode 12. The comparison electrode liquid that has passed through the REF electrode 212 is introduced into the waste liquid flow path 220 through the liquid junction 217.

  FIG. 3C is a flow chart showing the discharging operation. When the solenoid valve 207 is opened and the solenoid valve 205 is closed and the plunger of the syringe pump is pushed to perform a discharge operation, (a) the ISE portion filling operation and (b) the comparison electrode portion filling operation cause the waste liquid flow path 220 and the syringe The sample and the comparison electrode liquid accumulated in the pump are discharged to the waste liquid container 215.

  By performing the comparison electrode portion filling operation after performing the ISE portion filling operation, the sample solution is filled in the ISE electrode 211, the comparison electrode portion 12 is filled with the comparison electrode solution, and the comparison portion 217 is compared with the sample solution. The electrode solution comes into contact. As a result, the ISE electrode 211 and the REF electrode 212 are brought into a conductive state to form a circuit, so that the potential difference of the ISE with reference to the comparison electrode can be measured using the voltmeter 218. At the time of potential difference measurement, since the suction nozzle unit 201 also forms a part of the circuit, the suction nozzle rises and is separated from the sample container in order to insulate it from the sample solution or device that can be an electrical noise source.

  FIG. 4 shows an operation flow of the conventional electrolyte measurement unit 11.

After filling the sample container 213 with the sample (S41), the ISE unit filling operation is performed to suck a predetermined amount of sample liquid from the sample container 213 through the suction nozzle into the ISE channel 202 (S42). After that, after switching to the comparison electrode portion filling operation, a predetermined amount of the comparison electrode solution is sucked from the comparison electrode solution bottle 214 into the REF flow path 203 (S44), and then the potential difference between the ISE electrode 211 and the REF electrode 212 is changed by the voltmeter 218. Measurement is performed (S45), and the measured concentration is calculated through internal processing. The measured concentration is calculated by the following Nernst equation.
[Formula 1] E = E0 + RT / nF · ln (f · C)
E: electromotive force, E0: reference potential, R: gas constant, T: absolute temperature, n: number of charges of ions, F: Faraday constant, ln: natural logarithm, f: activity coefficient, C: concentration of ions Since the REF electrode 12 is in contact with the reference electrode solution having a constant electrolyte concentration every time, the constant reference potential E0 is always generated. Therefore, the potential of the ISE electrode with the potential of the REF electrode as the reference potential E0 can be measured, and the ion (electrolyte) concentration C in the sample solution can be calculated.

  After the concentration measurement is completed, the waste liquid operation is performed at the programmed timing, the waste liquid in the syringe pump 210 is discharged (S46), and the plunger position is returned. Thereafter, the process returns to S41 again to measure the next sample, the sample in the sample container 213 is replaced, and the ISE unit filling operation is started for the next sample. In the automatic analyzer, the above operation is repeated as many times as the number of measurement samples, thereby enabling continuous repeated measurement on a plurality of samples.

  Note that the sample replacement operation (S41) and the discharge operation (S46) in the sample container may be performed in parallel with other operations as long as noise that is a level that affects the potential difference measurement is not generated.

  When continuously measuring a plurality of samples, if the suction nozzle unit 201 moves up and down with the first sample (hereinafter referred to as “sample A”) filled up to the tip of the suction nozzle, vibration during vertical driving is performed. Also, the sample A falls from the tip of the nozzle (hereinafter referred to as a drop-off) due to fluctuations in the flow path internal pressure when the pinch valve 209 is closed, and the next sample (hereinafter referred to as the sample B) in the sample container 213 It may cause contamination of the standard solution.

  As a method for preventing this drop, the suction nozzle unit 201 is raised after the filling operation of the ISE unit in S42, and the syringe pump is driven in a state where the tip of the suction nozzle unit 201 is above the liquid surface of the sample liquid. An air region (hereinafter referred to as an air gap) is created at the tip (S43). By making the amount of the air gap to be created within a range that does not reach the ISE portion and that does not cause a drop, the drop can be prevented within a range that does not affect the potential difference measurement.

  However, when the sample B is sucked after measuring the sample A, the air gap created between the sample A and the sample B passes through the ISE electrode 211, and the sensitive film of the ISE electrode 211 is in contact with the air gap. In general, in the ISE method, when the sensitive membrane comes into contact with air during solution measurement, the measurement potential becomes temporarily unstable, and it takes time for the measurement potential to stabilize even if it comes into contact with the solution thereafter. It has been known.

In conventional electrolyte measurement devices, the timing at which the potential is stabilized is adjusted by adjusting the time until the potential measurement is performed after passing through the air gap in order to reduce the effect of potential instability due to the passage through the air gap. Although measures such as measurement are taken, the time adjustment for stabilization is required, which has been a limitation on the device design. In addition, when the air gap splits in the flow path due to factors such as device vibration or minute irregularities in the flow path, and the air gap remains in the flow path unintentionally at the timing of potential measurement Because there is a possibility that noise may occur in the measurement potential and accurate measurement cannot be performed, it is necessary to suck a sufficient amount of sample so that the split air gap can be discharged, and it is difficult to reduce the amount of sample used There was a problem such as.

<First embodiment of the present invention>
In this embodiment, an example of an electrolyte measuring device having an air gap removal flow path will be described. In FIG. 5, the example of a block diagram of the electrolyte measurement part in connection with 1st embodiment of a present Example is shown.

  In the present embodiment, an air gap removal channel 204 that connects the suction nozzle unit 201 and the syringe pump 210 and an electromagnetic valve 208 that is installed on the air gap removal channel 204 are installed upstream of the ISE electrode 211. As a basic operation, in addition to the conventional operation flow, (d) an air gap removal operation is provided.

  The basic operation in this embodiment will be described with reference to FIGS. 6A and 6B. There are four basic operations: (a) ISE portion filling operation, (b) reference electrode portion filling operation, (c) discharge operation, and (d) air gap removal operation.

  The operations (a) to (c) are performed in the same manner as the basic operation in the conventional electrolyte measurement unit. (D) In the air gap removal operation, after the measurement of the sample A is completed, the sample in the sample container 213 is replaced with the sample B which is the next sample, the suction nozzle unit 201 is lowered, and the tip of the suction nozzle is introduced into the sample B Implement in the state. In order to introduce the air gap created at the tip of the suction nozzle portion 201 into the air gap removal flow path 204, the syringe valve is driven with the solenoid valve 208 opened and the solenoid valves 205 and 7 and the pinch valve 209 closed. Remove the air gap. After the air gap removal operation is completed, the sample B sucked from the suction nozzle by the ISE portion filling operation is transferred to the ISE electrode 211 by executing the ISE portion filling operation while the tip of the suction nozzle is introduced into the sample B. Conducted. As described above, the sample B can be introduced without the air gap passing through the ISE electrode 211 by executing the bubble removing operation.

  FIG. 7 illustrates an operation flow in this embodiment.

  After the sample is introduced into the sample container (S71), the tip of the suction nozzle unit 201 is introduced into the sample container 213 and an air gap removing operation is executed (S72), so that the suction nozzle unit is used for the previous sample measurement. The air gap sucked at the tip of 201 is removed to the air gap removal flow path 204. Thereafter, the operation is switched to the ISE portion filling operation to suck a predetermined amount of sample (S73), an air gap is created again at the tip of the suction nozzle (S74), and the operation is switched to the comparison electrode portion filling operation (S75). After measuring the potential difference between the ISE and the reference electrode with the voltmeter 218 (S76), the discharging operation is performed (S77). When there is a sample to be measured next, after the sample in the sample container 213 is replaced, the bubble removing operation is executed again. Thereafter, the number of samples to be measured is repeated. If the air gap created during the previous sample measurement is not in the flow path (for example, in the case of the first measurement), the air gap removal operation (S72) can be omitted.

The syringe pump drive amount necessary for air gap removal is determined based on the air gap amount sucked at the previous measurement, the distance from the tip of the suction nozzle unit 201 to the air gap removal flow path inlet 219, the sample suction speed, and the like. The switching timing between the bubble removing operation and the ISE portion filling operation is determined by the syringe pump suction amount.

<Second embodiment of the present invention>
In the present embodiment, an embodiment will be described in which the shape of the nozzle direct connection branch passage 211 that communicates the fluid sucked from the suction nozzle to the air gap removal passage 204 and the ISE passage 202 will be described.

  When a fluid filled in a channel having a constant inner diameter is sucked at a constant flow rate, the moving speed is different between the vicinity of the inner wall of the channel and the vicinity of the center of the channel. Generally, the fluid moving speed is slower near the inner wall of the flow channel than at the center of the flow channel. Therefore, if there is an air gap in the flow path in which the liquid moves, the air has a smaller elastic modulus than water, so the air gap area is deformed and splits due to the difference in velocity between the inner wall and the center of the flow path. there is a possibility. Furthermore, since the force acting on the air gap increases as the moving speed increases, the possibility of splitting increases. In addition, when there is a step such as a coupling part or a connector on the inner wall of the flow path, there is a possibility that the moving air gap may be split by an impact caused by the step.

  FIG. 8 shows an example of a flow path structure for avoiding bubble breakup and effectively removing bubbles. A branch portion (air gap removal channel inlet) communicating with the air gap removal channel 204 is provided on the upper side in the vertical direction with respect to the channel communicating with the ISE channel 202. As a result, the air gap flowing in the flow path is easily introduced into the air gap removal flow path 204.

  The flow path inner diameter d of the general ISE flow path 202 is φ0.5 mm to 1.0 mm, and the flow gap inner diameter D of the air gap removal flow path 204 is φ1.1 mm to 3 larger than the inner diameter D of the ISE flow path 202. A range of 0.0 mm is desirable. Further, in order to prevent the air gap from being split due to the presence of a step on the inner wall of the nozzle direct connection branch passage 211, there is a step such as a connector between the tip of the suction nozzle portion 201 and the air gap removal passage inlet 219. It is desirable to integrally mold so that there is no. Furthermore, it is desirable that the flow path inner wall from the suction nozzle portion 201 to the ISE flow path 202 is formed smoothly, and the bending region is formed so as to draw a gentle curve.

  By making the nozzle direct connection branch flow path 211 as described above, the inner diameter D of the air gap removal flow path 204 is larger than the inner diameter d of the ISE flow path 202, so that the plunger operating speed of the syringe pump is the same. However, the moving speed of the sample and the air gap introduced into the air gap removal flow path 204 becomes slow, and it becomes difficult to split. Further, due to the capillary phenomenon, an air gap is hardly introduced into the ISE flow path 202 having a small inner diameter.

  According to the present embodiment, even when a plurality of samples are continuously measured, the air gap is not introduced into the ISE section. Therefore, the measurement potential is reduced by contacting the sensitive film of the ISE electrode 211 and the air gap. Instable state is prevented and continuous measurement is possible. Further, it is possible to reduce the risk of noise due to the air gap remaining in the ISE flow path 202 being mixed into the ISE part during potential measurement.

  In one embodiment of the present embodiment, the air gap removal flow path inlet 219 is installed at a position 40 mm from the tip of the suction nozzle portion 201. The flow path inner diameter of the flow path connected from the tip of the suction nozzle unit 201 to the ISE flow path 202 is φ0.8 mm, whereas the inner diameters of the air gap removal flow path 204 and the air gap removal flow path port 19 are φ1.6 mm. The air gap removal channel 204 has a larger inner diameter than the ISE channel 202. The distance to the end to which the ISE channel 202 is connected is approximately 60 mm. The amount of air sucked in order to create an air gap for preventing dripping is 10 μL.

  After measuring Sample A, 10 μL of air is sucked to create an air gap. At this time, an air gap exists over a section of about 20 mm from the tip of the suction nozzle portion 201, and the initial sample A is filled in the ISE flow channel 202 downstream thereof.

  In this state, when the tip of the suction nozzle unit 201 is introduced into the sample container 213 containing the sample B and the syringe pump is driven while performing the air gap removal operation, the air gap generated at the tip of the suction nozzle unit 201 The amount of suction volume necessary for removing the water from the ISE channel 202 is 21 μL. Therefore, in the present embodiment, in the air gap removal operation, it is only necessary to switch to the ISE portion filling operation after sucking a volume of at least 21 μL.

When the inner diameter of each flow path, the connection position of the air gap removal flow path inlet 219, and the like are different, the suction amount of the syringe pump can be calculated by the above method. The suction volume may be set in consideration of the influence of bubble deformation or splitting depending on conditions such as the inner diameter of each flow path and the installation position of the air gap removal flow path inlet 219.

<Third embodiment of the present invention>
In the present embodiment, an example of an analyzer that detects and removes an air gap using a bubble detector will be described. FIG. 9 is a diagram illustrating a configuration example of an apparatus according to the third embodiment of the present embodiment.

  In the present embodiment, a bubble detector 216 is provided between the tip of the suction nozzle unit 201 and the air gap removal channel inlet 219. In other words, the bubble detector 216 is installed on the upstream side of the branch portion of the flow path connected to the air gap removal flow path 204 and the ISE flow path 202.

  As the bubble detector 216, for example, a part or the whole of a nozzle is formed of a light-transmitting material, and a detector based on an optical principle for optically detecting the presence or absence of an air gap in the flow channel from the outside of the flow channel is used. In addition, a detector based on the electrical principle of detecting the presence or absence of an air gap by measuring the electrical resistance in the flow path, such as a Coulter counter, may be used. The detector may be a detector according to another method as long as it does not generate a step or vibration that causes the air gap to break in the flow path.

  FIG. 10 shows an example of the operation flow in the present embodiment.

  The sample replacement in the sample container (S101) and the air gap removal operation (S102) are performed by the same operation flow as in the first embodiment. While the air gap removing operation (S102) is being performed, it is monitored whether the bubble detector 216 has detected air (S103). When the bubble detection unit 16 detects air, it is determined that the air gap is passing, and the air gap removal operation is continued.

  When air is not detected by the bubble detector 216, it is determined that the air gap has already passed through a certain area of the bubble detector 16, and the bubble detector is detected when the detection state is switched from the state with air to the state without air. After the volume between 216 and the air gap removal channel inlet 219 is sucked into the air gap removal channel 204, the air gap removal operation is switched to the ISE portion filling operation (S104). After the ISE portion filling operation is completed, the air gap creation operation (S105), the comparison electrode portion filling operation (S106), the potential difference measurement (S107), and the discharge operation (S108) are executed as in the first embodiment.

According to the present embodiment, even when the air gap is broken or mixed due to an unexpected factor, it can be reliably removed to the air gap removal flow path 204, and higher reliability is ensured. Measurement can be realized. As a result, it is not necessary to provide a wide margin for the amount sucked by the third suction operation in consideration of the volume change of the air gap, and the analysis can be performed with the minimum operation time and the sample amount. It is possible to shorten the sample amount.

1 Sample disk 2 Reagent disk 3 Reaction disk 4 Reaction tank 5 Sampling mechanism 6 Reagent dispensing mechanism 7 Stirring mechanism 8 Photometric mechanism 9 Washing mechanism 10 Computer (PC)
DESCRIPTION OF SYMBOLS 11 Electrolyte measurement part 12 Memory | storage device 13 Control part 14 Piezoelectric element driver 15 Stirring mechanism controller 16 Sample container 17 Circular sample disk 18 Reagent bottle 19 Circular reagent disk 20 Cold storage 21 Reaction container 22 Reaction container holder 23 Drive mechanism 24 Sample probe 25 Sample Probe support shaft 26 Sample probe arm 27 Reagent probe 28 Reagent probe support shaft 29 Reagent probe arm 30 Electrolyte measurement sampling mechanism 31 Fixed portion 33 Nozzle 34 Vertical drive mechanism 35 Electrolyte measurement sample probe 36 Electrolyte measurement sample probe support shaft 37 Electrolyte Sample probe arm for measurement 201 Suction nozzle section 202 ISE flow path 203 REF flow path 204 Air gap removal flow path 205, 206, 207, 208 Electromagnetic valve 209 Pinch valve 210 Rinjiponpu 211 ISE electrode 212 REF electrodes 213 sample containers 214 reference electrode liquid bottle 215 waste container 216 bubble detector 217 liquid junction 218 voltmeter 219 air gap removal flow path inlet 220 waste channel 221 nozzles direct branch channel

Claims (9)

A sensor unit for measuring a component contained in the liquid;
A nozzle for sucking gas and liquid contained in the container;
A first flow path connecting the nozzle and the sensor unit;
A second flow path connecting the sensor unit and the pump;
A third flow path branched from the first flow path and connected to the second flow path or the pump;
A switching unit for switching whether the fluid sucked by the nozzle is introduced into the first channel or the second channel;
A control hand for controlling the switching unit to introduce the liquid sucked from the nozzle into the first flow path and to introduce the gas sucked from the nozzle into the third flow path. A featured automatic analyzer.
The automatic analyzer according to claim 1,
A nozzle drive unit for driving the nozzle unit up and down with respect to the container to suck liquid or gas from the nozzle;
The controller is
A first suction operation in which the nozzle is immersed in a liquid in a container to suck the liquid and introduce it into the sensor;
A second suction operation for sucking the gas without immersing the nozzle in the liquid in the container;
A third suction operation for introducing the sucked gas into the third flow path,
An automatic analyzer that controls operations of the switching unit, the pump, and the nozzle driving unit so that the third suction operation is executed before the first suction operation is executed.
The automatic analyzer according to claim 1,
The automatic analyzer is characterized in that the third channel is branched and connected to the first channel.
The automatic analyzer according to claim 2,
The automatic analyzer is characterized in that a cross-sectional area of the third flow path is larger than a cross-sectional area of the first flow path.
The automatic analyzer according to claim 1,
An automatic analyzer having a member integrally formed with the nozzle and a branch portion to the third flow path.
The automatic analyzer according to claim 1,
An automatic analyzer comprising a detector for detecting the presence or absence of gas between a branching portion to the third flow path and a nozzle tip.
The automatic analyzer according to claim 5,
The said control part controls opening and closing of the said valve based on the timing which detected presence of gas with the said detector, The automatic analyzer characterized by the above-mentioned.
In a method of continuously analyzing a plurality of sample liquids using a sensor,
A first sample introduction step of introducing a first sample liquid into a flow path connected to the sensor;
An analysis process for analyzing components in the first sample liquid introduced into the sensor;
A discharge step of discharging the first sample liquid whose measurement is completed from the sensor;
A second sample introduction step of introducing a second sample liquid to be continuously measured into the flow path,
Further, after the first sample introduction step and before the second sample introduction step, the gas introduction step of introducing gas into the flow channel, and the gas introduced into the flow channel are introduced into the flow channel. And a gas removal step of removing the gas from the flow path via a branch flow path branched from the flow path.
The analysis method according to claim 7,
A determination step of determining whether or not there is gas in the flow path;
An analysis method, wherein the gas removal step is performed when it is determined by the determination step that there is a gas.