Patent Publication Number: US-2021165009-A1

Title: Electrolyte analyzing device

Description:
TECHNICAL FIELD 
     The present invention relates to an electrolyte analyzing device. 
     BACKGROUND ART 
     An electrolyte analyzing device is a device for measuring a concentration of a specific electrolyte contained in an electrolyte solution such as human blood and urine, and uses an ion selective electrode to measure the concentration. As a general measurement method, serum which is an electrolyte solution is directly supplied to an ion selective electrode, or a sample solution diluted with a dilute solution is supplied to the ion selective electrode to measure a solution potential with a reference electrode solution. Next (or prior to the measurement), a standard solution is supplied to the ion selective electrode, the solution potential with the reference electrode solution is measured in the same manner, and an electrolyte concentration of the sample solution is calculated based on two solution potential levels. 
     In this way, in a flow-type electrolyte analyzing device, reagents such as the dilute solution, the standard solution, and the reference electrode solution are used as consumables, and replacement of these reagents is performed by a user. The flow-type electrolyte analyzing device often includes a dedicated suction nozzle for each of these reagents, and it is general that the dedicated suction nozzle and the reagent are always in contact with the solution while the reagent is loaded on the device. In the replacement performed by the user, a series of operations are performed until the dedicated suction nozzles are arranged in the reagent containers. 
     Since these reagents have different components, when different reagents come into contact with the suction nozzle due to a mistake made by the user during replacing the reagent container, or when the reagents scatter during the replacement and contamination between the reagents occurs, there are problems that a correct measurement result cannot be obtained, a consumable reagent becomes unusable, and a reagent flow path of the device needs to be rewashed. In particular, the reference electrode solution is preferably an aqueous solution having a concentration higher than that of the dilute solution or the standard solution in view of stability of the analysis by the ion selective electrode, so that methods for preventing the contamination with other reagents are essential. 
     PTL 1 discloses a specimen analyzing device having, as the method for preventing the contamination, a function of notifying the user a reagent that is a wrong reagent, a reagent whose remaining amount is insufficient, or a reagent that is expired by attaching an information storage unit such as a radio frequency identifier (RFID) to a reagent container and providing, in the analyzing device, an information reading unit that reads information in the information storage unit. Further, in PTL 1, a cover is provided on a container setting unit for setting a reagent container, and a locking mechanism for permitting and prohibiting closing of the cover and a control unit thereof are provided to prevent misplacement performed by a user. 
     CITATION LIST 
     Patent Literature 
     PTL 1: JP-A-2011-209207 
     SUMMARY OF INVENTION 
     Technical Problem 
     In the specimen analyzing device disclosed in PTL 1, electronic power needs to be supplied to the specimen analysis apparatus to prevent misplacement. In the configuration in PTL 1, by applying an electric current to a solenoid of the reagent container setting unit, the cover of the reagent container setting unit is controlled to be locked in a closed state or an open state to prevent misplacement of the reagent container. On the other hand, when the electric current is not applied to the solenoid, the cover of the reagent container setting unit is unlocked. Therefore, when the specimen analysis apparatus is not powered on, the user can open and close the cover of the reagent container setting unit to perform the replacement of the reagent container without the lock control of the cover performed by the control unit. 
     If the reagent container can be replaced during a period when the analyzing device is not in operation, there is an advantage that it is not necessary to interrupt the measurement and an operation rate of the analyzing device can be increased. On the other hand, even the analyzing device manages reagent information with the RFID, when the device is not powered on, each mechanism cannot be controlled. Therefore, when the suction nozzle comes in contact with a different reagent due to a human error or the like, the above contamination risk occurs. Therefore, instead of completely disabling the reagent replacement when the analyzing device is not powered on, it is desirable that a part of the replacement, specifically, operations until the suction nozzle is brought into contact with the reagent are allowed even when the device is not powered on. 
     The present invention has been made in view of the above circumstances, and provided is an electrolyte analyzing device that prevents contamination caused by different reagents coming into contact with a suction nozzle when reagent replacement is performed by a user. 
     Solution to Problem 
     An electrolyte analyzing device according to an aspect of an embodiment of the invention includes: a substrate on which a reagent container is set; a suction nozzle that suctions a reagent from the reagent container; a nozzle support part that is coupled to the suction nozzle and is movable between a reagent container replacement position and a reagent suction position; a locking mechanism that is fitted with the nozzle support part moved to the reagent container replacement position and fixes the nozzle support part at the reagent container replacement position; and an unlocking mechanism that releases fitting of the nozzle support part and the locking mechanism in a power-on state. When the reagent container satisfies a predetermined condition, the unlocking mechanism is controlled to release the fitting between the nozzle support part and the locking mechanism, so that the nozzle support part moves to the reagent suction position. 
     Other technical problems and novel characteristics will be apparent from a description of the description and the accompanying drawings. 
     Advantageous Effect 
     Even when the reagent container is replaced during a power of the device being cut off, contamination can be prevented. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  shows an overall schematic diagram of an electrolyte analyzing device. 
         FIG. 2  illustrates an appearance of the electrolyte analyzing device (schematic view). 
         FIGS. 3( a ), 3( b ) and 3( c )  illustrate states of a reagent container setting unit when a reagent container is replaced. 
         FIG. 4  illustrates a first configuration example of the reagent container setting unit. 
         FIG. 5A  illustrates a state in which a nozzle support part is locked by a locking mechanism. 
         FIG. 5B  illustrates a state in which the nozzle support part is unlocked by an unlocking mechanism. 
         FIGS. 6( a ), 6( b ) and 6( c )  show configuration examples of the locking mechanism and the unlocking mechanism. 
         FIG. 7A  shows an example of a reagent container replacement flow in a device power-on state. 
         FIG. 7B  shows an example of a reagent container replacement flow in a device power-cutoff state. 
         FIG. 8  illustrates a second configuration example of a reagent container setting unit. 
         FIG. 9A  illustrates a third configuration example of a reagent container setting unit (plan view). 
         FIG. 9B  illustrates the third configuration example of the reagent container setting unit (side view). 
         FIG. 10  illustrates a fourth configuration example of a reagent container setting unit (top view). 
         FIG. 11  illustrates a configuration example of a nozzle support part in the fourth configuration example of the reagent container setting unit. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
       FIG. 1  shows an overall schematic diagram of an electrolyte analyzing device. The electrolyte analyzing device is not limited to a device alone, and may be mounted on an automatic analyzing device. Examples of the automatic analyzing device include a biochemical automatic analyzing device, an immunological automatic analyzing device, and the like. Alternatively, the electrolyte analyzing device maybe mounted on a mass spectrometer used for clinical examination or a coagulation analyzing device that measures blood coagulation time, may be mounted on a combined system of the mass spectrometer, the coagulation analyzing device, the biochemical automatic analyzing device and the immunological automatic analyzing device, or may be mounted on an automatic analysis system applying these analyzing devices. 
     The electrolyte analyzing device shown in  FIG. 1  is a flow-type electrolyte analyzing device using anion selective electrode (hereinafter referred to as ISE electrode).  FIG. 1  shows five mechanisms including a sample dispensing part, an ISE electrode unit, a reagent part, a mechanism part, and a waste solution mechanism as main mechanisms of the electrolyte analyzing device, and a control device that controls these mechanisms and that calculates and displays an electrolyte concentration based on a measurement result. 
     The sample dispensing part includes a sample probe  14 . The sample probe  14  dispenses a sample such as a patient specimen held in a sample container  15  and transmits the sample into the analyzing device. Here, the specimen is a general term for analysis targets collected from a living body of a patient, and is, for example, blood or urine. An analysis target obtained by performing a predetermined pretreatment on blood, urine, or the like is also referred to as a specimen. 
     The ISE electrode unit includes a dilution tank  11 , a sipper nozzle  13 , a dilute solution nozzle  24 , an internal standard solution nozzle  25 , an ISE electrode  1 , a reference electrode  2 , a pinch valve  23 , a voltmeter  27 , and an amplifier  28 . The sample dispensed by the sample dispensing part is discharged to the dilution tank  11 , and is diluted and stirred with a dilute solution discharged from the dilute solution nozzle  24  into the dilution tank  11 . The sipper nozzle  13  is connected to the ISE electrode  1  by a flow path, and the diluted sample solution suctioned from the dilution tank  11  is sent to the ISE electrode  1  through the flow path. On the other hand, a reference electrode solution housed in a reference electrode solution bottle  5  is sent to the reference electrode  2  by operating a sipper syringe  10  in a state where the pinch valve  23  is closed. When the diluted sample solution sent to the ISE electrode through the flow path and the reference electrode solution sent to the reference electrode through the flow path come into contact with each other, the ISE electrode  1  and the reference electrode  2  are electrically conducted. The ISE electrode unit measures a concentration of a specific electrolyte contained in the sample based on a potential difference between the ISE electrode  1  and the reference electrode  2 . 
     Specifically, the ISE electrode  1  is attached with an ion sensitive membrane having a property that a electromotive force changes according to a concentration of a specific ion (for example, sodium ion (Na + ), potassium ion (K + ), chlorate ion (Cl − ) , and the like) in a sample solution, and the ISE electrode  1  outputs an electromotive force according to a concentration of each ion in the sample solution, so that the voltmeter  27  and the amplifier  28  acquire the electromotive force between the ISE electrode  1  and the reference electrode  2 . The control device  29  calculates the concentration of the ion in the sample based on the acquired electromotive force for each ion, and displays the concentration. The sample solution remaining in the dilution tank  11  is discharged by the waste solution mechanism. 
     The potential difference between the ISE electrode  1  and the reference electrode  2  is influenced by a temperature change and the like. In order to correct a potential change due to the influence of such temperature change and the like, in a period from one sample measurement being finished to a next sample measurement, an internal standard solution is discharged from the internal standard solution nozzle  25  into the dilution tank  11 , and the measurement is performed in the same manner as in the case of the above sample (however, dilution for the internal standard solution is not performed). It is preferable to make a correction according to a change amount using a measurement result of the internal standard solution performed between the sample measurements. 
     The reagent part includes a suction nozzle  6  that suctions a reagent from a reagent container, a degassing mechanism  7 , and a filter  16 , and supplies a reagent necessary for measurement. When the electrolyte measurement is performed, three types of reagents, which are the internal standard solution, the dilute solution, and the reference electrode solution, are used as the reagent, and an internal standard solution bottle  3  in which the internal standard solution is housed, a dilute solution bottle  4  in which the dilute solution is housed, and a reference electrode solution bottle  5  in which the reference electrode solution is housed are set in the reagent part.  FIG. 1  shows this state. A cleaning solution bottle that stores a cleaning solution when the device is cleaned is set in the reagent part. 
     The internal standard solution bottle  3  and the diluting solution bottle  4  are respectively connected to the internal standard solution nozzle  25  and the dilute solution nozzle  24  through the flow path via the filter  16 , and each nozzle is provided in the dilution tank  11  with a tip end of the nozzle introduced therein. The reference electrode solution bottle  5  is connected to the reference electrode  2  through the flow path via the filter  16 . Each degassing mechanism  7  is connected to a respective one of the flow path between the dilute solution bottle  4  and the dilution tank  11 , and the flow path between the reference electrode solution bottle  5  and the reference electrode  2 . A degassed reagent is supplied into the dilution tank  11  and the reference electrode  2 . Accordingly, a negative pressure is applied to the flow path by a syringe to suction up the reagent from the bottle, so that a gas dissolved in the reagent appears as bubbles in the reagent. A degassing mechanism is provided, so that the reagent is not supplied to the dilution tank  11  or the reference electrode  2  with bubbles contained therein. 
     The mechanism part includes an internal standard solution syringe  8 , a dilute solution syringe  9 , a sipper syringe  10 , electromagnetic valves  17 ,  18 ,  19 ,  20 ,  21 ,  22 ,  30 , and a preheat  12 , and feeds liquid within each mechanism or between the mechanisms and the like. For example, the internal standard solution and the dilute solution are sent to the dilution tank  11  by respective operations of the internal standard solution syringe  8  and the dilute solution syringe  9  and operations of the electromagnetic valves provided in the flow path. The preheat  12  reduces the influence of the temperature on the ISE electrode  1  by controlling temperatures of the internal standard solution and the dilute solution reaching the ISE electrode  1  within a certain range. 
     The waste solution mechanism includes a first waste solution nozzle  26 , a second waste solution nozzle  36 , a vacuum bottle  34 , a waste solution receiver  35 , a vacuum pump  33 , and electromagnetic valves  31 ,  32 , and discharges the sample solution remaining in the dilution tank  11  and a reaction solution remaining in the flow path of the ISE electrode unit. 
     Electrolyte concentration measuring operations performed by an electrolyte measuring device shown in  FIG. 1  will be described. The measuring operations are controlled by the control device  29 . 
     First, the sample dispensed from the sample container  15  by the sample probe  14  of the sample dispensing part is discharged to the dilution tank  11  of the ISE electrode unit. After the sample is dispensed into the dilution tank  11 , the dilute solution nozzle  24  discharges the dilute solution from the dilute solution bottle  4  by an operation of the dilute solution syringe  9  to dilute the sample. As described above, in order to prevent bubbles from being generated due to changes in the temperature and pressure of the dilute solution in the flow path, the degassing mechanism  7  attached in a middle of the dilute solution flow path performs a degassing process. The diluted sample solution is suctioned into the ISE electrode  1  by operations of the sipper syringe  10  and the electromagnetic valve  22 . 
     On the other hand, the pinch valve  23  and the sipper syringe  10  send the reference electrode solution into the reference electrode  2  from the reference electrode solution bottle  5 . The reference electrode solution is, for example, a potassium chloride (KCl) aqueous solution having a predetermined concentration, and when the sample solution and the reference electrode solution are in contact with each other, the ISE electrode  1  and the reference electrode  2  are electrically conducted to each other. An electrolyte concentration of the reference electrode solution is preferably high so as to reduce the influence of the concentration change during the sending of the sample, but it is desirable that the concentration is between 0.5 mmol/L and 3.0 mmol/L since the solution may crystallize and cause clogging of the flow path when the concentration is near a saturation concentration. An ISE electrode potential with reference to a reference electrode potential is measured using the voltmeter  27  and the amplifier  28 . 
     The internal standard solution of the internal standard solution bottle  3  set in the reagent part before and after the sample measurement is discharged to the dilution tank  11  by the internal standard solution syringe  8 , and an electrolyte concentration of the internal standard solution is measured in the same manner as the sample measurement. 
     Using the ISE electrode potential measured for the sample solution, the control device  29  executes calculation to calculate the electrolyte concentration in the sample. At this time, by executing calibration based on the ISE electrode potential measured for the internal standard solution, the electrolyte concentration can be more accurately measured. 
     The control device can be configured as a computer including a central processing unit (CPU), a random access memory (RAM), a storage device, and an I/O port, and the RAM, the storage device, and the I/O port can exchange data with the CPU via an internal bus. The I/O port is connected to the above mechanisms to control operations thereof. The operations are controlled by reading the program stored in the storage device into the RAM and the CPU executing the program. An input/output device is connected to the control device  29 , so that an input from a user and display of a measurement result can be executed. 
     Next, a reagent container setting unit of the electrolyte analyzing device according to the present embodiment will be described.  FIG. 2  illustrates an appearance (schematic view) of the electrolyte analyzing device. A reagent container setting unit  502  in which the internal standard solution bottle  3 , the dilute solution bottle  4 , and the reference electrode solution bottle  5  are set can be drawn out from an opening  503  using a rail  501  with respect to a housing  500  of the device. The opening  503  is normally closed by a door (not shown), and when reagent container replacement is performed, the door is opened to replace the reagent container. When the reagent container replacement is performed, as shown in  FIG. 2  (right diagram), the user can easily replace the reagent container by drawing the reagent container setting unit  502  out of the housing  500 . After the reagent container replacement is performed, the reagent container setting unit  502  is stored again in the housing  500  ( FIG. 2  (left diagram)). 
       FIGS. 3( a ), 3( b ) and 3( c )  illustrate states of the reagent container setting unit when the reagent container is replaced. All cases in which (a) the reagent container setting unit  502  is stored, (b) the reagent container setting unit  502  is drawn, and (c) the reagent container is replaced are shown as perspective views from a side surface of the housing  500 . Hereinafter, a configuration example of the reagent container setting unit  502  will be described. 
     First Embodiment 
       FIG. 4  illustrates a first configuration example of the reagent container setting unit  502 . The figure illustrates a cross-sectional view (schematic diagram) of a state in which the suction nozzle  6  of the reagent container setting unit  502  is inserted into a reagent container  101 . In the reagent container setting unit  502 , a reagent container stand  204  is provided on a substrate  205 . By placing the reagent container  101  on the substrate  205  and coupling the substrate  205  to the rail  501  (not shown), the reagent container setting unit  502  can be taken in and out of the housing of the device. The suction nozzle  6  is coupled to a handle  202  and a nozzle support part  203  that can be moved up and down from the reagent container stand  204 . A power supply device  303  is connected to the reagent container setting unit  502 , and as described later, electric power is supplied to an unlocking mechanism  302 , a RFID reader/writer  103 , and a container detector  104 , which require the electric power for operations thereof. When the analyzing device is powered on, the power supply device  303  supplies electric power to the reagent container setting unit  502 , and when the analyzing device is powered off, the power supply device  303  does not supply electric power to the reagent container setting unit  502 . The figure shows a state in which the nozzle support part  203  is housed in the reagent container stand  204 . 
       FIG. 5A  illustrates a state in which the nozzle support part  203  is locked by a locking mechanism  301  . When the reagent container  101  is replaced by the user, the user manually lifts up the handle  202 , so that the suction nozzle  6  can be detached from the reagent container  101  without touching the suction nozzle  6 . When the nozzle support part  203  is lifted to an upper limit point, the locking mechanism  301  holds the nozzle support part  203  at a position shown in  FIG. 5A . This position is referred to as a reagent container replacement position. Accordingly, the user can let go of the handle  202  to replace the reagent container  101 . 
     The suction nozzle  6  is preferably configured with a fixed metal pipe, so that a nozzle tip end position does not shift from a placing position of the reagent container  101  when the user lifts up the handle  202 . Accordingly, it is possible to prevent the reagent from scattering around due to a shake of a suction nozzle tip end  6   a  associated with the operation. The shake is supposed to happen when the suction nozzle  6  is a flexible resin pipe. On the other hand, an end portion  6   b  of the suction nozzle  6  on a handle side is connected to a pipe (not shown) to connect the suction nozzle  6  to the flow path of the device. Using a flexible resin pipe as the pipe connected to the suction nozzle end portion  6   b , the reagent container setting unit  502  can be easily moved in and out of the housing, and the nozzle support part  203  can be easily moved up and down. 
     It is preferable that in the state in which the nozzle support part  203  is locked by the locking mechanism  301 , there is a predetermined distance ε between the suction nozzle tip end  6   a  and a reagent suction port  110  of the reagent container  101 . Accordingly, when the user replaces the reagent container  101 , the user does not need to hit the reagent container  101  with the suction nozzle tip end  6   a  or to tilt the reagent container and place the reagent container on the reagent container setting unit, so that it is possible to reduce risks of a spillage of the reagent from the reagent container  101 , scattering of the reagent from the suction nozzle tip end  6   a , and the like during replacement. 
       FIG. 5B  illustrates a state in which the nozzle support part  203  is unlocked by an unlocking mechanism  302  from the state shown in  FIG. 5A . The locking mechanism  301  is unlocked by the unlocking mechanism  302  under control of the control device  29  in a state in which electric power is supplied from the power supply device  303  to the unlocking mechanism  302 . At this time, it is desirable that the nozzle support part  203  is provided with a damper mechanism, so that the suction nozzle  6  and the nozzle support part  203  slowly descend even when the user does not grip the handle  202 . In the present example, the nozzle support part  203  is stopped when the nozzle support part  203  is fully descended, and a position thereof is referred to as a reagent suction position. 
       FIGS. 6( a ), 6( b ) and 6( c )  show configuration examples of the locking mechanism  301  and the unlocking mechanism  302 . The locking mechanism  301  includes a base on fixed side  601  and a base on movable side  602 , and a spring  604  is provided between the base on fixed side  601  and the base on movable side  602 . A bearing  603  is connected to a surface that faces a surface of the base on movable side  602  on which the spring  604  is provided. The unlocking mechanism  302  includes a solenoid  611 , and the solenoid  611  is connected to the base on movable side  602 . 
       FIG. 6( a )  shows that the reagent container setting unit  502  in normal conditions is in the state shown in  FIG. 4 . In the normal conditions, the solenoid  611  is off, and the bearing  603  is in contact with a guide part  203   a  of the nozzle support part  203 . At this time, since the spring  604  is compressed, the bearing  603  is pressed against the guide part  203   a  by an elastic force of the spring  604 . 
       FIG. 6( b )  shows that the reagent container setting unit  502  being locked is in the state shown in  FIG. 5A . Even when the reagent container setting unit  502  is locked, the solenoid  611  is off. When the nozzle support part  203  is lifted in a direction  621 , the bearing  603  is fitted with a lock recess part  203   b  provided in the nozzle support part  203 . Accordingly, the nozzle support part  203  is locked, so that the nozzle support part  203  does not descend even when the user releases the handle. At this time, a length of the spring  604  is close to a natural length. 
     In this way, using the elastic force of the spring regardless of whether or not the device is powered on, the suction nozzle  6  can be drawn out from the reagent container  101  by lifting the nozzle support part  203 , and the nozzle support part  203  can be locked in that state. Not only the spring but also an elastic body can be used, and the nozzle support part  203  may be locked by another mechanical operation as long as electric power is not required for the operation thereof. 
       FIG. 6( c )  shows that the reagent container setting unit  502  being unlocked is in the state shown in  FIG. 5B . The solenoid  611  is turned on, the bearing  603  and the base on movable side  602  are attracted in a direction  622 . Accordingly, the bearing  603  is pulled out from the lock recess part  203   b , and the nozzle support part  203  descends in a direction  623 . After a predetermined time, the solenoid  611  is turned off, and the bearing  603  comes into contact with the guide part  203   a  of the nozzle support part  203 . When the nozzle support part  203  is fully descended, the reagent container setting unit  502  returns to the normal conditions. 
     In order to operate the solenoid  611 , electric power is supplied to the solenoid  611 , and the control device  29  needs to control the solenoid  611  to turn on the solenoid  611 . Accordingly, in order to unlock the nozzle support part  203  and insert the suction nozzle  6  into the reagent container, it is necessary to supply electric power of the device. As long as the unlocking operation is controlled by the control device  29 , the unlocking mechanism  302  may unlock the nozzle support part  203  by another operation. For example, the nozzle support part  203  may be unlocked by pneumatic pressure that exceeds the elastic force of the spring. 
     Further, the reagent container  101  is provided with an RFID tag  102  on which information related to the reagent, such as a type of the reagent, an amount of remaining solution, an expiration date, and a lot number, is stored (see  FIG. 4 ). In order to exchange information with the RFID tag  102 , the reagent container stand  204  is provided with the RFID reader/writer  103  at a position facing the reagent container  101  that is placed on the reagent container stand  204 . A container detector  104  detecting that the reagent container  101  is placed at a reagent container placing position is provided. The container detector  104  includes, for example, a light source that emits infrared light and a photodetector that detects the infrared light. Presence or absence of the reagent container  101  is determined by the photodetector detecting presence or absence of the reflected light from the reagent container  101 . The RFID tag and the RFID reader/writer are examples, and it is sufficient that an information storage medium in which information related to the reagents to be stored is stored is attached to the reagent container, and an information reader provided in the reagent container setting unit can read the information related to the reagents to be stored and stored in the information storage medium. 
     Next, a flow of replacing the reagent container will be described. As described above, in the reagent container setting unit  502  according to the present embodiment, an original reagent container can be taken out and a new reagent container can be provided regardless of whether or not electric power of the device is supplied. On the other hand, the suction nozzle can be inserted into the new reagent container only when the electric power of the device is supplied.  FIG. 7A  shows an example of a reagent container replacement flow in a device power-on state, and  FIG. 7B  shows an example of a reagent container replacement flow in a device power-cutoff state. 
     Firstly, a reagent container replacement flow ( FIG. 7A ) in the device power-on state will be described. As described above, the user grips the handle  202  and lifts the nozzle support part  203  (S 702 ), and takes out the reagent container  101  (S 704 ) in a state in which the nozzle support part  203  is locked (S 703 ). Accordingly, reagent container detection performed by the container detector  104  is turned off (S 705 ). When a new reagent container  101  is placed on the reagent container setting unit  502  by the user again (S 706 ), the container detector  104  detects the new reagent container  101  (S 707 ). The RFID reader/writer  103  starts reading RFID information of the reagent container  101 , which is triggered by the detection of the reagent container performed by the container detector  104 . The control device  29  determines whether or not the reagent contained in the reagent container is normal based on the RFID information (S 708 ). Examples of specific determination contents include whether or not a type of reagent is a reagent that is to be placed in a place where the reagent is originally placed, whether or not enough solution remains, and whether or not the reagent expires. When the RFID information is normal, the control device  29  registers the read RFID information (S 709 ) and causes the unlocking mechanism  302  to unlock the locking mechanism  301  (S 710 ). The nozzle support part  203  automatically descends when the lock is released, and the suction nozzle  6  moves to a predetermined suction position in the reagent container  101 . On the other hand, when the RFID information is not normal, this fact is displayed on a display unit of the control device  29 . Accordingly, the user can replace the suction nozzle  6  with a correct reagent container before bringing the suction nozzle  6  into contact with a wrong reagent (S 704  to S 706 ). In this way, since the suction nozzle  6  contacts the normal reagent only, contamination due to misplacement of the reagent container performed by the user can be prevented. 
     Next, a reagent container replacement flow ( FIG. 7B ) in the device power-cutoff state will be described. Steps having the same contents as those in the replacement flow in  FIG. 7A  are designated by the same reference numerals. The user grips the handle  202  and lifts the nozzle support part  203  (S 702 ), and replaces the reagent container  101  (S 704 , S 706 ) in a state in which the nozzle support part  203  is locked (S 703 ). As described above, the locking mechanism  301  according to the present embodiment can mechanically lock the nozzle support part  203  without being supplied with electric power. When the device power is turned on by the user (S 721 ) , the device checks a state of the container detector  104  of the reagent container setting unit  502  as one of initialization processes (S 722 ), and when the container detector  104  detects the reagent container  101 , the RFID information is checked using the detection as a trigger (S 708 ). When the RFID information is normal, the control device  29  registers the read RFID information (S 709 ) and causes the unlocking mechanism  302  to unlock the locking mechanism  301  (S 710 ). On the other hand, when the reagent container is not detected, or when the RFID information is not normal, this fact is displayed on the display unit of the control device  29  as a failed replacement (S 724 ). In this case, since the device power is already turned on, the process proceeds to step S 704  or S 705  in  FIG. 7A  to execute the reagent replacement process. If the replacement terminates normally (S 723 ), then if necessary, the control device  29  automatically executes a solution replacement operation in the flow path and an analysis preparation operation. 
     Generally, in the electrolyte analyzing device, in initial processing after electric power is turned on, the electrolyte analyzing device has a function of automatically executing an operation of sending the solutions into the flow path, an operation of checking the device status, a washing operation, and the like, and a function of allowing a transition to an analysis operation in a short time. However, when it is recognized that a remaining amount of the reagent is not sufficient after the initial processing and the reagent container is replaced, the solution replacement operation in the flow path and the like is required again, which results in that a time is required to start the analysis. According to the present embodiment, the user can perform the reagent replacement while maintaining effect of preventing the contamination between the reagents even when the device power is cut off, and can use the device without additional operations after electric power is supplied. 
     Further, the reagent container  101  is a container made of a transparent or translucent material. As long as the reagent container setting unit  502  is easily visible to the user, it is convenient that the user can visually check the remaining amount of the reagent and can replace the reagent in advance if necessary before turning on the power supply of the device. 
     Second Embodiment 
       FIG. 8  illustrates a second configuration example of the reagent container setting unit  502 . A main difference in the second configuration example from the first configuration example is that two suction nozzles  6 - 1 ,  2  are coupled to the nozzle support part  203 , and the two suction nozzles  6 - 1 ,  2  can be simultaneously lifted by lifting the handle  202  by the user. Although omitted in  FIG. 8 , the container detector  104  and the RFID reader/writer  103  shown in  FIG. 4  are provided respectively corresponding to reagent containers  101 - 1 ,  2 . A reagent container replacement flow is also similar to those shown in  FIGS. 7A and 7B . When one or more reagent containers are replaced by the user and RFID information of all reagent containers is normal, the unlocking mechanism  302  unlocks the nozzle support part  203 , so that the suction nozzles  6 - 1 ,  2  respectively move to predetermined suction positions in the reagent containers  101 - 1 ,  2 .  FIG. 8  shows an example of two reagent containers, but three or more reagent containers may be used. 
     According to this configuration, the user can simultaneously perform required reagent container replacement with a single lifting/descending operation of the nozzle support part  203 , thus improving efficiency of the replacement. In the analyzing device that can store a plurality of reagent containers of the same reagent in the reagent container setting unit  502  and can switch and use other reagent containers when the remaining amount of the reagent in one reagent container becomes small, even when a normal reagent is not placed at all positions, an unlocking condition may be a condition that at least the reagents necessary for analysis are normally placed one by one. The unlocking condition is that the necessary reagents are correctly placed and no abnormal reagent is placed, so that the suction nozzle  6  can be prevented from coming into contact with an inappropriate reagent. 
     Third Embodiment 
     As shown in  FIG. 8 , with the configuration in which a plurality of reagent containers are arranged side by side in the reagent container setting unit  502 , the reagent container setting unit can be made compact, and the efficiency of the replacement can be improved as described in a second embodiment. Since in the electrolyte analyzing device as shown in  FIG. 1 , three reagents including the internal standard solution, the dilute solution, and the reference electrode solution are used, a configuration of the reagent container setting unit  502  in which these three reagent containers are placed will be examined as a third embodiment. Since the reagent container is replaced manually, it is not possible to eliminate a risk of contamination occurring due to reagent scattering from the suction nozzle, solution spilling from the suction port of the reagent container, or the like during the replacement. In particular, when a plurality of reagent containers are placed side by side in close proximity to one another, an operation error of the user easily causes the contamination. However, in the case of the reagent in the electrolyte analyzing device and in the case of the internal standard solution and the dilute solution, even when some reagents scatter, influence thereof can be ignored in most cases. On the other hand, since the reference electrode solution contains ions at a higher concentration than the internal standard solution and the dilute solution, it is necessary to more strictly manage the risk of contamination. 
       FIGS. 9A and 9B  are configuration examples (third configuration example) of the reagent container setting unit  502  on which three reagent containers are placed, and in particular, are configurations suitable for an electrolyte analyzing device that uses two reagents having a relatively low concentration and one reagent having a relatively high concentration.  FIG. 9A  is a plan view, and  FIG. 9B  is a side view when seen from an arrow direction shown in  FIG. 9A . Display of the handle  202  is omitted in  FIG. 9A . 
     In this configuration, three types of reagent containers of a dilute solution and a standard solution that have a relatively low concentration and a reference electrode solution that has a relatively high concentration can be placed, so that the risk of contamination is reduced. Specifically, a dilute solution bottle and an internal standard solution bottle are placed as juxtaposed reagent containers  101 - 1 ,  101 - 2 , and a reference electrode solution bottle is placed as a reagent container  101 - 3  at a position separated from the containers  101 - 1 ,  101 - 2  by the reagent container stand  204 . Therefore, when three reagent containers are placed on the reagent container setting unit shown in  FIGS. 9A and 9B , the reagent container stand  204  is interposed between the reagent suction port  110  of the dilute solution bottle or the reagent suction port  110  of the internal standard solution bottle and the reagent suction port  110  of the reference electrode solution bottle. The state in which the handle  202  is lifted up is the same as that in  FIG. 5A , and in the state in which the nozzle support part  203  is locked, the reagent container stand  204  is interposed between the tip end of the suction nozzle  6  for the dilute solution or the tip end of the suction nozzle  6  for the internal standard solution and the tip end of the suction nozzle  6  for the reference electrode solution. Accordingly, even when reagent scattering from a tip end of a reference electrode solution suction nozzle  6 - 3 , solution spilling from a reagent suction port of the reagent container (reference electrode solution bottle)  101 - 3 , or the like occurs during the replacement, the reagent container stand  204  plays a role as a partition, and can reduce a risk of mixing reagents from the reference electrode solution bottle into other reagent containers to a low level. Further, when the nozzle support part  203  has a plate shape as shown in  FIG. 8 , since the reagent container is replaced in a state in which the nozzle support part  203  is lifted up, the nozzle support part  203  also can play a role as the partition. 
     In addition, as an additional effect of changing a setting direction of the reagent container only for the reference electrode solution, for example, when the user replaces all three types of reagent containers, the dilute solution bottle and the standard solution bottle that are placed side by side can be easily taken out with both hands at the same time. Thus, efficient operations can be performed with these reagents having a low contamination risk. On the other hand, the reference electrode solution bottle having a high contamination risk is arranged to prompt replacement of only this reagent container. By shifting a replacement timing of the reagent container having high contamination risk from a replacement timing of other reagent containers, the risk of the contamination due to the scattering of the reagent during the replacement of the reagent container can be reduced. 
     A shape of the reagent container  101  can be regarded as a rectangular parallelepiped shape having a rectangular upper surface (chamfering or unevenness on the reagent container is not hindered), so that the reagent suction port  110  of the reagent container  101  is arranged at a position closer to a short side than a center position of an upper surface. Accordingly, a distance from the nozzle support part  203  to the reagent suction port  110  can be kept short even when the reagent containers are arranged in a longitudinal direction as shown in  FIGS. 8 and 9A . In order to utilize that the reagent suction port  110  is close to an end portion (short side) and make it easier for the user to hold the reagent container, it is also desirable to provide a handle for the reagent container in an empty space on the upper surface of the container. 
     In the reagent container setting unit shown in  FIGS. 9A  and  9 B, the plurality of reagent containers  101 - 1 ,  2  arranged side by side and the reagent container  101 - 3 , which is separated from the reagent containers  101 - 1 ,  2  by the reagent container stand  204 , are placed in different directions. That is, the reagent containers  101 - 1 ,  2  are provided so that each of the short sides of the upper surfaces thereof faces one predetermined surface of the reagent container stand, and the reagent container  101 - 3  is placed so that a long side of the upper surface thereof faces a back surface of the one predetermined surface of the reagent container stand. Accordingly, the reagent container setting unit can be made compact as a whole, and as shown in  FIG. 9A , the reagent suction ports  110 - 1  to  110 - 3  of the respective reagent containers  101 - 1  to  101 - 3  can be arranged at the same distance from a center of the nozzle support part  203 . In this case, for example, as compared with an arrangement layout in which three reagent containers are juxtaposed in a same direction, effect that the lengths (lengths between the tip end of the suction nozzle that is inserted into the reagent container and the end portion of the suction nozzle that is connected to the pipe that forms the flow path) of the suction nozzles of each reagent can be made uniform, and effect that a movable (flexible) flow path portion connected to the suction nozzle  6  can be centralized in one place are obtained. 
     In the configurations in  FIGS. 9A and 9B , similarly to the configuration in  FIG. 8 , it is desirable to control the unlocking condition, so that unlocking is performed only when all necessary reagents are prepared. For example, an LED indicator light may be provided near the placing position of the reagent container in the reagent container setting unit, and the user may be notified by turning on/blinking/turning off the LED of the reagent container that needs to be replaced. 
     As reagents that can be stored in the reagent container increase, more of the number of times of replacement of the reagent container can be reduced, which is efficient. Therefore, it is desirable that a height of the reagent container is as large as possible in accordance with heights of the reagent container setting unit  502  and the opening  503  of the housing  500  (see  FIG. 3 ). Alternatively, it is desirable to make the heights of the reagent container setting unit  502  and the opening  503  of the housing  500  as small as possible according to the height of the reagent container so as to make the device compact. Here, in the reagent container setting unit  502 , if the state in which the nozzle support part  203  is locked is the state in  FIG. 5A  and the height of the reagent container  101  is higher than that in the state in  FIG. 5A , the reagent container  101  and the suction nozzle tip end  6   a  are likely to come into contact with each other or the reagent container  101  needs to be tilted and placed at the placing position during the replacement of the reagent container, which increases the risk of the contamination.  FIG. 10  shows a fourth configuration example (bird&#39;s-eye view) of the reagent container setting unit  502  that solves such a problem.  FIG. 10  shows a state in which nozzle support parts ( 801 ,  811 ) are drawn out from the reagent container stand  204  and locked. 
     In the reagent container setting unit  502  shown in  FIG. 10 , when the reagent container  101  is placed on the substrate  205 , an upper end of the reagent suction port  110  is slightly lower than an upper end of the reagent container stand  204 . That is, it is assumed that a reagent container having a capacity as large as possible within a capacity of the reagent container setting unit  502  is placed. Even in such a case, in order to allow the predetermined distance ε between the suction nozzle tip end  6   a  and the upper end of the reagent suction port  110  of the reagent container  101  (see  FIG. 5A ), in the configuration in  FIG. 10 , the nozzle support part  203  includes a plurality of pillars  801 ,  811 . In addition, in the state in which the nozzle support part  203  is locked by the locking mechanism  301 , when a position of the suction nozzle tip end  6   a  is near or above the upper end of the reagent container stand  204 , the contamination may occur due to vibration of the suction nozzle tip end  6   a . Therefore, among the plurality of pillars (two in the figure) of the nozzle support part  203 , a lower pillar  811  has a plate shape and has a function of the shielding plate for reducing the occurrence of contamination. As shown in  FIG. 10 , in the state in which the nozzle support part  203  is locked, both a first line connecting a suction nozzle tip end  6   a - 1  and a suction nozzle tip end  6   a - 3 , and a second line connecting a suction nozzle tip end  6   a - 2  and the suction nozzle tip end  6   a - 3  are in a state of being shielded by the lower pillar (shielding plate)  811 . Accordingly, even when the reagent scattering from the reference electrode solution suction nozzle  6 - 3 , the solution spilling from the reagent suction port of the reagent container (reference electrode solution bottle)  101 - 3 , or the like occurs during the reagent container replacement, the reagent container stand  204  and the lower pillar (shielding plate)  811  plays a role as the partition, and the risk of mixing reagents from the reference electrode solution bottle into other reagent containers can be reduced to a low level. 
     All of the suction nozzle end portions  6   b - 1  to  6   b - 3  are set to come close to the center of the handle  202 , and flexible resin pipes forming the flow paths are connected. 
       FIG. 11  illustrates a configuration example of the nozzle support part  203  applied to the reagent container setting unit  502  in  FIG. 10 . In  FIG. 11 , (a) illustrates a state in normal conditions, and (b) illustrates a locked state. The nozzle support part  203  includes an upper stage first pillar  801  and a lower stage second pillar (hereinafter referred to as a shielding plate)  811 . The shielding plate  811  is provided with a pulley with damper function  814  on an upper side of the shielding plate  811  and a pulley  815  on a lower side of the shielding plate  811 , and a belt  816  is hung between the pulley with damper function  814  and the pulley  815 . The first pillar  801  is connected to the belt  816  by a first belt holding unit  813   a , and the reagent container stand  204  is connected to the belt  816  by a second belt holding unit  813   b , so that the first pillar  801  and the shielding plate  811  are interlockingly lifted up. The first belt holding unit  813   a  is engaged with a first linear guide  812   a , and the second belt holding unit  813   b  is engaged with a second linear guide  812   b , so that lifting and descending operations of the nozzle support part  203  can be stably performed. Regarding the damper function of the pulley with damper function  814 , it is desirable that a torque is generated only when the pulley  814  descends. Accordingly, a load on the user can be reduced during a manual lifting operation. 
     By configuring the nozzle support part in this way, a movement stroke H of the nozzle support part  203  can be made larger than a height h of the reagent container setting unit  502  in the normal conditions. In this way, even when the height of the reagent container setting unit  502  is equivalent to that of the reagent container, the suction nozzle tip end can be sufficiently separated from the reagent container, and by giving at least the lower pillar a function of the shielding plate, the occurrence of the contamination can be reduced. 
     REFERENCE SIGN LIST 
     
         
           1  ion selective electrode 
           2  reference electrode 
           3  internal standard solution bottle 
           4  dilute solution bottle 
           5  reference electrode solution bottle 
           6  suction nozzle 
           6   a  suction nozzle tip end 
           6   b  suction nozzle end portion 
           7  degassing mechanism 
           8  internal standard solution syringe 
           9  dilute solution syringe 
           10  sipper syringe 
           11  dilution tank 
           12  preheat 
           13  sipper nozzle 
           14  sample probe 
           15  sample container 
           16  filter 
           17 ,  18 ,  19 ,  20 ,  21 ,  22 ,  30 ,  31 ,  32  electromagnetic valve 
           23  pinch valve 
           24  dilute solution nozzle 
           25  internal standard solution nozzle 
           26  first waste solution nozzle 
           27  voltmeter 
           28  amplifier 
           29  control device 
           33  vacuum pump 
           34  vacuum bottle 
           35  waste solution receiver 
           101  reagent container 
           102  RFID tag 
           103  RFID reader-writer 
           104  container detector 
           110  reagent suction port 
           202  handle 
           203  nozzle support part 
           203   a  guide part 
           203   b  lock recess part 
           204  reagent container stand 
           205  substrate 
           301  locking mechanism 
           302  unlocking mechanism 
           303  power supply device 
           500  housing 
           501  rail 
           502  reagent container setting unit 
           503  opening 
           601  base on fixed side 
           602  base on movable side 
           603  bearing 
           604  spring 
           611  solenoid 
           621 ,  622 ,  623  direction 
           801  first pillar 
           811  second pillar (shielding plate) 
           812   a ,  812   b  linear guide 
           813   a ,  813   b  belt holding unit 
           814  pulley with damper function 
           815  pulley 
           816  belt