Analyzing device and condition detecting method

Abstract

To provide a technique of specifying an abnormality cause without requiring information about a known potential waveform in an analysis device using an ion selective electrode.SOLUTION: An analysis device for analyzing the characteristics of liquid having the conductivity comprises: a flow channel to which liquid is supplied; an electrode which is provided in the flow channel and comes into contact with the liquid; a liquid-feeding mechanism for introducing the liquid into the flow channel; an electric signal acquisition unit for acquiring an electric signal output from the electrode; a storage unit which stores a model that expresses the liquid in the flow channel, the electrode and the liquid-feeding mechanism as an electric circuit; and a circuit simulator unit which can simulate the electric signal based on the model. The electric state changes of the liquid in the flow channel, the electrode, and the liquid-feeding mechanism are estimated by simulating the electric signal by the circuit simulator unit.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an analyzer and a condition detection method. [Background technology]

[0002] In order to quickly and easily measure the concentrations of ions (electrolytes) such as potassium, sodium, and chloride in biological sample fluids such as blood, an analytical device is equipped with multiple ion selective electrodes (ISEs) corresponding to the ions to be detected.

[0003] The electrolyte analysis unit having the ion-selective electrodes is mounted, for example, on an automatic analyzer, which is suitably used alone or as a component of an automatic biochemical analyzer for automatic, rapid, and continuous clinical testing.

[0004] Ion-selective electrodes are used in combination with a reference electrode, and the activity (concentration) of a target ion can be determined by measuring the potential difference between the ion-selective electrode and the reference electrode. In the field of clinical testing, there is a high need to quantify the concentration of electrolytes contained in biological sample fluids such as blood, especially serum, plasma, and urine. These samples can be measured directly using an ion-selective electrode, a so-called non-dilution method. Alternatively, a so-called dilution method can be used, in which a predetermined amount of diluent is added to a predetermined amount of sample, mixed, and diluted, and then measured using an ion-selective electrode.

[0005] The dilution method has the advantages of requiring a small amount of sample, low concentrations of coexisting substances such as proteins and lipids in the measurement solution, little effect of contamination from coexisting substances, and high stability of the ion-selective electrode. Therefore, the combination of a flow-cell ion-selective electrode and the dilution method is currently the mainstream in the analysis of electrolyte concentrations using automatic analyzers. A container called a dilution tank is used to dilute the sample, and the diluted sample (measurement solution) prepared in the dilution tank is sent through piping to the flow-cell ion-selective electrode for measurement. An internal standard solution is dispensed into the dilution tank alternately with the sample, and measurements are performed alternately with the sample.

[0006] Electrolyte concentrations in living organisms are usually maintained within a narrow range, and even slight changes in concentration can have significant clinical and therapeutic implications. Therefore, ion-selective electrodes are required to have extremely high measurement accuracy, and various technologies have been developed to minimize measurement errors.

[0007] For example, Patent Document 1 describes a method for identifying the cause of measurement errors in an ion-selective electrode by referring to the potential at the timing of driving the component to identify a defective component. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Patent Publication No. 2021-018141 Summary of the Invention [Problem to be solved by the invention]

[0009] There are various causes of errors in measurement values, such as air bubbles entering the flow path between the ion-selective electrode and the reference electrode, vibration of the liquid in the flow path, and electrical noise entering the measurement system. These causes abnormalities in the device, which can prevent the normal potential from being output.

[0010] In the conventional analyzer described in Patent Document 1, the cause of an abnormality in the analyzer is identified based on a change in the measured potential. In this method, the cause of the abnormality is determined based on the characteristics of the change in the measured potential (potential waveform), so it is necessary to clarify in advance the relationship between the characteristics of the potential waveform and the cause of the abnormality.

[0011] Therefore, the present disclosure provides a technique for identifying the cause of an abnormality in an analytical device using an ion-selective electrode without requiring information on a known potential waveform. [Means for solving the problem]

[0012] An example of an analytical device according to the present invention is An analytical device for analyzing characteristics of a conductive liquid, comprising: a flow path to which a liquid is supplied; an electrode provided in the flow channel and in contact with the liquid; a liquid delivery mechanism for introducing a liquid into the flow channel; an electrical signal acquiring unit for acquiring an electrical signal output from the electrode; a storage unit that stores a model that represents the liquid in the flow path, the electrodes, and the liquid delivery mechanism as an electric circuit; a circuit simulator unit capable of simulating the electrical signal based on the model; Equipped with The electrical state changes of the liquid in the flow path, the electrodes, and the liquid delivery mechanism are estimated by simulating the electrical signals in the circuit simulator section.

[0013] An example of a state detection method according to the present invention includes: A state detection method performed by an analyzer for analyzing characteristics of a conductive liquid, comprising: The analysis device a flow path to which a liquid is supplied; an electrode provided in the flow channel and in contact with the liquid; a liquid delivery mechanism for introducing a liquid into the flow channel; an electrical signal acquiring unit for acquiring an electrical signal output from the electrode; a storage unit that stores a model that represents the liquid in the flow path, the electrodes, and the liquid delivery mechanism as an electric circuit; a circuit simulator unit capable of simulating the electrical signal based on the model; Equipped with The state detection method includes: a step in which the electrical signal acquiring unit acquires a potential waveform based on a potential associated with the liquid supplied to the flow channel; the circuit simulator unit acquires an approximate waveform based on the model and the acquired potential waveform, and acquires parameters related to voltage, electrical resistance, capacitance, and inductance associated with the approximate waveform; a step in which the analysis device compares the acquired parameters with threshold information related to the parameters stored in the storage unit; a step of estimating an electrical state change of the analysis device based on the result of the comparing step; Equipped with. [Effects of the Invention]

[0014] The analytical device according to the present disclosure can analyze the cause of an abnormality in an analytical device that uses an ion selective electrode. Problems, configurations, and effects other than those described above will become apparent from the following description of the embodiments. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a schematic diagram showing an analysis device according to a first embodiment. [Figure 2] 3 shows an equivalent circuit of the analyzer according to the first embodiment. [Figure 3] 10 shows a simulation result of a potential waveform according to the first embodiment. [Figure 4] 3 is a flowchart of an analysis method according to the first embodiment. [Figure 5] 10 is a flowchart of an analysis method according to a second embodiment. [Figure 6] FIG. 10 is a schematic diagram showing an analysis device according to a third embodiment. [Figure 7]FIG. 10 is a schematic diagram showing an analysis device according to a fourth embodiment. [Figure 8] FIG. 10 is a schematic diagram showing an analysis device according to a fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. [First embodiment] <Example of analytical equipment configuration> 1 is a schematic diagram showing an analysis device 100 according to a first embodiment. The analysis device 100 is an analysis device that analyzes the properties of a conductive liquid.

[0017] As shown in FIG. 1, the analysis device 100 includes an electrolyte analysis unit 1, an electrical signal acquisition unit 2, an input unit 3, a control unit 4, a concentration calculation unit 5, an abnormality determination unit 6, a display unit 7, a circuit simulator unit 8, and a memory unit 9.

[0018] The electrolyte analysis unit 1 includes three types of ion selective electrodes 101 to 103 (for example, the ion selective electrode 101 is a chloride ion electrode, the ion selective electrode 102 is a potassium ion electrode, and the ion selective electrode 103 is a sodium ion electrode), a comparison electrode 104 (reference electrode), a pinch valve 105, a vacuum suction nozzle 106, a sipper nozzle 107, a diluent supply nozzle 108, an internal standard solution supply nozzle 109, a dilution tank 110, a waste tank 111, a vacuum pump 112, solenoid valves 121 to 127, an internal standard solution syringe pump 131, a diluent solution syringe pump 132, a sipper syringe pump 133, an internal standard solution bottle 141, a diluent solution bottle 151, and a comparison electrode solution bottle 161.

[0019] The analysis device 100 includes a flow path through which a liquid is supplied. For example, the above-described components of the electrolyte analysis unit 1 are interconnected by the flow path.

[0020] The vacuum pump 112, the internal standard syringe pump 131, the diluent syringe pump 132, and the sipper syringe pump 133 are examples of a liquid delivery mechanism for introducing liquid into the flow path. The liquid delivery mechanism may also include other components of the electrolyte analyzing unit 1 (e.g., pinch valve 105, vacuum suction nozzle 106, sipper nozzle 107, diluent supply nozzle 108, internal standard supply nozzle 109, dilution tank 110, waste tank 111, liquid junction 120, solenoid valves 121 to 127, internal standard bottle 141, diluent bottle 151, and reference electrode solution bottle 161).

[0021] The ion selective electrodes 101 to 103 and the reference electrode 104 are examples of electrodes provided in the flow path and in contact with the liquid. Of these, the ion selective electrodes 101 to 103 are electrodes that respond to the concentration of a specific ion, respectively, thereby making it possible to measure the specific ion. For example, a flow cell type ion selective electrode can be used as the ion selective electrodes 101 to 103. The number of ion selective electrodes 101 to 103 can be changed depending on the number of ion species to be measured. Furthermore, the ion selective electrodes 101 to 103 are applicable to all ion species. The ion selective electrodes 101 to 103 generate an electromotive force (electric potential) corresponding to the ion concentration in the sample liquid.

[0022] A reference electrode solution bottle 161 contains a reference electrode solution (reference solution), and the reference solution is introduced into the flow path of the reference electrode 104 by a sipper syringe pump 133. For example, an aqueous potassium chloride solution can be used as the reference solution. The reference electrode 104 generates a potential corresponding to the ion concentration in the reference electrode solution.

[0023] An internal standard solution (IS) is stored in an internal standard solution bottle 141 , and the internal standard solution is dispensed into a dilution tank 110 by an internal standard solution syringe pump 131 and an internal standard solution supply nozzle 109 .

[0024] The specimen is dispensed into the dilution tank 110 by a sampling mechanism (not shown). A diluent is contained in the diluent bottle 151, and the diluent is dispensed into the dilution tank 110 by the diluent syringe pump 132 and the diluent supply nozzle 108, and mixed with the specimen.

[0025] In this way, an internal standard solution or a mixture of a specimen and a diluent is introduced into the dilution tank 110 as the sample solution to be analyzed.

[0026] Here, we will explain the operation when filling the measurement flow path with the sample liquid filled in dilution tank 110. First, when introducing the liquid filled in dilution tank 110 into the flow path of ion selective electrodes 101 to 103, solenoid valves 121 and 125 are closed, pinch valve 105 and solenoid valve 122 are opened, sipper nozzle 107 is lowered into dilution tank 110, and sipper syringe pump 133 is caused to suck in the liquid.

[0027] Next, when introducing the reference electrode solution into the flow path of the reference electrode 104, the solenoid valve 121 is opened, the pinch valve 105 is closed, and the sipper syringe pump 133 is caused to perform suction, thereby introducing the reference electrode solution from the reference electrode solution bottle 161 into the flow path of the reference electrode 104. Furthermore, to discharge the solution accumulated in the sipper syringe pump 133, the solenoid valve 122 is closed, the solenoid valve 125 is opened, and the sipper syringe pump 133 is caused to pump the solution.

[0028] The comparison electrode solution introduced into the flow path of the comparison electrode 104 and the sample solution introduced into the ion selective electrodes 101 to 103 come into contact at the liquid junction 120, and the ion selective electrodes 101 to 103 and the comparison electrode 104 are electrically connected through the liquid.

[0029] After the sample solution is introduced into the flow paths of the ion selective electrodes 101 to 103 and the reference electrode solution is introduced into the flow path of the reference electrode 104, the vacuum suction nozzle 106 is lowered and the vacuum pump 112 is driven to suck up the sample solution (analyte or internal standard solution) remaining in the dilution tank 110 and discard it into the waste liquid tank 111. The reference electrode solution introduced into the reference electrode 104 is discarded into the waste liquid tank 111 by operating the solenoid valve 122, the vacuum pump 112, and the sipper syringe pump 133.

[0030] The potential difference between the reference electrode 104 and each of the ion selective electrodes 101 to 103 changes depending on the concentration of analyte ions in the sample liquid introduced into the flow path of the ion selective electrodes 101 to 103. Hereinafter, the potential difference may be referred to as potential or electromotive force.

[0031] The electrical signal acquiring unit 2 acquires electrical signals output from the ion selective electrodes 101 to 103 and the reference electrode 104. The electrical signal acquiring unit 2 outputs potentials measured based on the acquired electrical signals to the concentration calculating unit 5, the abnormality determining unit 6, and the circuit simulator unit 8. The function of controlling the timing of the potentials to be output, and the functions of the concentration calculating unit 5, the abnormality determining unit 6, and the circuit simulator unit 8, are sometimes referred to as the potential analyzing unit 10.

[0032] The concentration calculation unit 5 calculates the electrolyte concentration in the sample solution based on the potential measurement results obtained by the electrical signal acquisition unit 2. Any known method can be used to measure the electrolyte concentration. The abnormality determination unit 6 can determine whether or not there is an abnormality by calculating, for example, the standard deviation, the difference between the maximum and minimum values, or the average value as an indicator of the soundness of the measured potential over a specified time range, and comparing these with threshold information stored in the memory unit 9.

[0033] Although details will be described later, the circuit simulator unit 8 simulates the potential change of the potential measured by the electrical signal acquisition unit 2 and analyzes the cause of the abnormality in the analysis device 100.

[0034] The input unit 3 is an input device such as a mouse, keyboard, or touch panel, and is used by the user to input various data and instructions to the control unit 4, concentration calculation unit 5, abnormality determination unit 6, and circuit simulator unit 8.

[0035] The control unit 4 controls the operation of the components in the analysis device 100, the potential measurement in the electrical signal acquisition unit 2, and the processing in the concentration calculation unit 5, the abnormality determination unit 6, and the circuit simulator unit 8. The control unit 4 receives input from the input unit 3. Note that the processing in the control unit 4, the electrical signal acquisition unit 2, the concentration calculation unit 5, the abnormality determination unit 6, and the circuit simulator unit 8 may be executed by a single processor installed in the analysis device 100.

[0036] The display unit 7 displays the results of the processing in the concentration calculation unit 5, the abnormality determination unit 6, and the circuit simulator unit 8, as well as a GUI screen.

[0037] The memory unit 9 stores data and processing results required for processing by the concentration calculation unit 5, the abnormality determination unit 6, and the circuit simulator unit 8. As data required for processing by the circuit simulator unit 8, the memory unit 9 stores data indicating the relationship between the potential measured by the electrical signal acquisition unit 2 and the cause of the abnormality in the analysis device 100.

[0038] 1 shows a configuration in which the storage unit 9 is built into the analysis device 100. However, the present invention is not limited to this, and the storage unit 9 can be used in any configuration, such as a configuration in which it is connected to the Internet, a configuration in which it is removable from the analysis device 100, a configuration in which a storage medium is connected to the analysis device 100, or a combination of these configurations.

[0039] The memory unit 9, concentration calculation unit 5, abnormality determination unit 6, and circuit simulator unit 8 are configured to be able to send and receive data, and can also be connected to a network or the Internet, for example, to acquire measurement data online.

[0040] For example, the electrical signal acquiring unit 2, the circuit simulator unit 8, and the storage unit 9 may be connected via a communication network. As a more specific example, the connection 170 between the electrical signal acquiring unit 2 and the circuit simulator unit 8 may be the Internet. In this way, functions can be distributed to provide a more convenient configuration.

[0041] It should be noted that the electrical signal acquisition unit 2, input unit 3, control unit 4, concentration calculation unit 5, abnormality determination unit 6, display unit 7, circuit simulator unit 8, and memory unit 9 do not all need to be built into the analytical device 100; some of these may be provided in other devices, and data may be exchanged by communication between the other devices and the analytical device 100.

[0042] <How to identify the cause of error> FIG. 2 is an equivalent circuit that represents the electrical state of the flow paths through which the ion-selective electrodes 101 to 103, the reference electrode 104, the sipper nozzle 107, the sample liquid, the reference liquid, and the waste liquid pass in the analytical device 100. In other words, it is an example of an equivalent circuit model that represents the liquids in the flow paths, the electrodes, and the liquid delivery mechanism as an electrical circuit. As an index (parameter) of the electrical state, C x is the capacitance, R x is the electrical resistance, V x is the voltage, L x represents the inductance (where x is an integer equal to or greater than 1 as shown in Figure 2). Note that the parameter C x , R x , L x Instead of or in addition to these, the parameter Z representing the impedance x may also be used.

[0043] This equivalent circuit model is stored in, for example, the storage unit 9. Based on this equivalent circuit model, the circuit simulator unit 8 can simulate the electrical signals output from the ion selective electrodes 101-103. Note that the electrical signals represent, for example, the potentials between the ion selective electrodes 101-103 and the reference electrode 104, and this potential can be said to be the potentials of the ion selective electrodes 101-103 expressed with the reference electrode 104 as a reference.

[0044] Each parameter of the equivalent circuit model fluctuates based on the electrochemical changes that occur due to the operation of components such as the measurement operation sequence and the movement of the sample solution in the flow channel. At this time, each fluctuation can be defined as a function with time t as a variable, and the simulated potential V expected to be acquired by the electrical signal acquisition unit 2 can be calculated as sim (t) is expressed as the following equation 1 using a function of various parameters. V sim (t)=f(C x (t),R x (t),V x (t),L x (t),…)(Formula 1)

[0045] For example, in the equivalent circuit model in Figure 2, R5(t), R6(t), R7(t), and R8(t) represent the electrical resistance in the flow path. When air bubbles enter the flow path, these values ​​can be considered to increase compared to their normal values.

[0046] Also, for example, V2(t) represents the electromotive force generated between the electrode and the sample solution. V2(t) varies not only with the electrolyte concentration of the sample solution but also with the temperature.

[0047] For example, V4(t) represents the liquid-liquid interfacial potential generated at the interface where the sample liquid and the reference liquid come into contact, and V4(t) changes depending on the state of the liquid-liquid interface.

[0048] In this way, changes in the electrical state due to abnormalities in the airtightness of the flow path, abnormalities in temperature control, abnormalities in liquid transfer, etc. are reflected in the potential output from the device. Furthermore, these changes are reflected in the potential in a form that also includes the operational sequence of the components. Therefore, for the output potential, an equivalent circuit model can be used that expresses, as an electrical circuit, not only the changes in the electrical circuit in an abnormal state but also the dynamic behavior (time-varying behavior) of the various components based on the operational sequence.

[0049] That is, the equivalent circuit model can represent the dynamic behavior of the liquid in the flow path, the electrodes, and the liquid delivery mechanism based on the operation sequence. In this case, the storage unit 9 may store a time chart of this operation sequence. In this way, a simulation based on a specific operation sequence can be performed.

[0050] Figure 3 shows the potential V(t) and the simulated potential V(t) for (a) normal and (b) abnormal conditions. sim (t) shows the simulated potential V sim (t) is, for example, in a specific circuit as shown in Figure 2, C x (t), R x (t), V x (t), L x This can be obtained by inputting specific values ​​into (t).

[0051] As shown in Figure 3(a), the simulated potential V(t) is used to approximate the normal V(t). sim At (t), all parameter values ​​are considered to be within the normal range. On the other hand, as shown in Fig. 3(b), the simulated potential V(t) that approximates V(t) at the abnormal time is sim At (t), the value of one of the parameters is considered to be outside the normal range.

[0052] From the results in Figure 3, the simulated potential V sim Since the shape of the potential V(t) closely matches that of the potential V(t), it can be seen that the electrical state of the analysis device 100 is largely reflected. simC used to output (t) x (t), R x (t), V x (t), L x By referring to (t), the electrical state of the device can be grasped. In this way, the analytical device 100 can estimate changes in the electrical state of the liquid in the flow path, the electrodes, the liquid delivery mechanism, the analytical device 100 as a whole, etc., by simulating the electrical signals in the circuit simulator unit 8.

[0053] This makes it possible to estimate the cause of an abnormality from information about the electrical state. The analysis device 100 estimates a change in the electrical state based on the voltage, electrical resistance, capacitance, inductance, and impedance calculated by simulating the electrical signal, and the threshold information stored in the memory unit 9. Furthermore, the cause of the abnormality can be identified based on the estimated change in the electrical state. As a specific example, C x (t), R x (t), V x (t), L x If any of (t) is outside the normal range, the location of the abnormality can be identified based on which parameter is outside the normal range, and the nature of the abnormality can be identified based on how it is outside the normal range.

[0054] The equivalent circuit shown here represents only a part of the analytical device 100, and an equivalent circuit model including other components can be created as needed. Changes in the circuit configuration due to electrochemical phenomena occurring at solid-liquid interfaces or liquid-liquid interfaces can also be incorporated into this equivalent circuit model. For example, the C shown in FIG. x (t), R x (t), V x (t), L x In either (t), the time change due to such electrochemical phenomenon may be defined, and / or a new C x (t), R x (t), V x (t), L x(t) may be added. In this way, the equivalent circuit model may represent changes in the circuit configuration due to electrochemical phenomena occurring at the solid-liquid interface or the liquid-liquid interface. In this way, estimation can be performed taking into account various electrochemical phenomena.

[0055] When introducing a phenomenon model that cannot be directly expressed as a parameter in the equivalent circuit, C x (t), R x (t), V x (t), L x The equivalent circuit model may be expressed using an index related to (t). The equivalent circuit model can also be changed based on the operation sequence. This can be done by setting a model created in advance based on time chart information of the operation sequence stored in the storage unit 9, or by manually inputting the model through the input unit 3. For example, the analysis device 100 may have a circuit simulator input unit that accepts input of parameters or equivalent circuit models used in the simulation into the circuit simulator unit 8 or the storage unit 9, and the input unit 3 can function as such a circuit simulator input unit. This allows for support for a wider variety of models.

[0056] 4 shows a flowchart illustrating a specific method for identifying the cause of an abnormality using the circuit simulator unit 8 having the circuit simulation function. This flowchart shows an example of a state detection method executed by the analysis device 100.

[0057] First, in step S401, when the user inputs an instruction to start the operation from the input section 3, the control section 4 drives the electrolyte analyzing unit 1, and the measurement operation is started.

[0058] In step S402, the electrolyte analyzing unit 1 introduces the sample liquid dispensed into the dilution tank 110 into a flow path equipped with the ion selective electrodes 101-103.

[0059] In step S403, the electrical signal acquiring unit 2 measures the potential difference between each of the ion selective electrodes 101 to 103 and the reference electrode 104, and outputs the measured potential to the concentration calculating unit 5, the abnormality determining unit 6, and the circuit simulator unit 8. Here, the electrical signal acquiring unit 2 acquires a potential waveform based on the potential associated with the liquid supplied to the flow path. At this time, the potential to be output may cover all timings when the components are operating, or may be limited to a certain time range.

[0060] The potential output to the circuit simulator 8 is treated as a potential V(t) for abnormality analysis in step S403-1, and a simulated potential V(t) that approximates the potential waveform is generated in step S403-2. sim (t) is obtained and stored in the memory. For example, the V that is most similar to V(t) is obtained. sim (t) gives C x (t), R x (t), V x (t), L x In this way, the circuit simulator unit 8 obtains an approximate waveform based on the equivalent circuit model and the obtained potential waveform, and obtains parameters related to the voltage, electrical resistance, capacitance, inductance, and impedance associated with the approximate waveform. As an approximation method, the least squares method, maximum likelihood estimation, Bayesian estimation, etc., can be used. This can be set in advance by the input unit 3 and / or the control unit 4.

[0061] In step S404, the concentration calculation unit 5 acquires the potential for concentration conversion. In step S405, the abnormality determination unit 6 compares the standard deviation, the difference between the maximum value and the minimum value, the average value, and the like as indicators of the soundness of the potential with the respective threshold information stored in the storage unit to determine whether or not there is an abnormality. Note that the abnormality determination here is performed using the C acquired in step S403-2. x (t), R x (t), V x (t), L x The (t) values ​​are not necessary (although these values ​​can of course be used).

[0062] If it is determined in step S405 that there is no abnormality, the process proceeds to step S406, where the concentration calculation unit 5 calculates the concentration, and the calculated concentration is displayed on the display unit 7 in step S407.

[0063] If it is determined in step S405 that there is an abnormality, the C x (t), R x (t), V x (t), L x (t) is referenced and acquired in step S405-1.

[0064] Next, in step S405-2, the analyzer 100 compares each parameter acquired in step S405-1 with the threshold information for each parameter stored in the storage unit. Based on the result of this comparison, the analyzer 100 estimates changes in the electrical state of the liquid in the flow path, the electrodes, the liquid delivery mechanism, the entire analyzer 100, etc. For example, the cause of the abnormality can be identified based on whether or not a parameter has exceeded a threshold, the type of parameter that has exceeded the threshold, the degree to which the threshold has been exceeded, etc.

[0065] In particular, in this embodiment, the analyzer 100 estimates electrical state changes of the liquid in the flow path, the electrodes, and the liquid delivery mechanism based on a comparison between the electrical signals output from the ion selective electrodes 101-103 and the reference electrode 104 and the approximate waveforms. That is, estimating the electrical state changes of the analyzer 100 includes estimating the electrical state changes of the liquid in the flow path, the electrodes, and the liquid delivery mechanism. This allows estimation based on specific temporal changes in potential.

[0066] The memory unit stores the relationship between each parameter and the related components, and when a parameter exceeds a threshold, it is possible to identify the related components and the abnormal state (cause of the abnormality) of the components that is thought to have caused the threshold to be exceeded.

[0067] Furthermore, multiple thresholds may be defined for the same parameter, in which case different causes of anomalies can be identified depending on whether each threshold is exceeded. Since there may be multiple causes of anomalies, multiple causes of anomalies (or their possibilities) may be identified for one piece of threshold information. It is also possible to store information such as the frequency of occurrence for each cause of anomaly.

[0068] The memory unit 9 also stores the relationships between parameters, making it possible to identify the cause of an abnormality based on the combination of parameters that exceed a threshold. The relationships described above can be set and changed as desired.

[0069] In addition to this method, another method for identifying the cause of an abnormality in a component is to store multiple equivalent circuit models in advance in a storage unit, which represent abnormal states in which the values ​​of various parameters are set to values ​​outside the normal range, and then generate an abnormal simulated potential V sim-fault It is also possible to identify the cause of an abnormality based on an evaluation of the similarity between the potential V(t) and the potential V(t). The selection of the abnormality determination method can be set in advance by the input unit 3 and / or the control unit 4.

[0070] In step S405-3, the identified cause of the abnormality is displayed on the display unit 7. At this time, the display unit displays not only the cause of the abnormality but also the type, value, threshold value, potential V(t), and simulated potential V sim It can be set to display (t).

[0071] In step S405-4, it is selected whether or not to suspend the measurement. If not suspending, the process proceeds to step S406, and if suspending, the process proceeds to step S408. In step S408, it is selected whether or not to measure the next sample liquid, and if suspending, the process proceeds to step S402 and the measurement is resumed. If not measuring the next sample liquid, the measurement ends in step S409.

[0072] <Technical effect> As described above, the analysis device 100 according to this embodiment generates a simulated potential V that approximates the potential V(t). sim (t) and V sim By comparing each parameter in (t) with threshold information, the cause of measurement error can be identified based on the relationship between multiple parameters and the degree to which they exceed the threshold. This allows the user to identify areas that may be causing measurement errors and how to improve them. This reduces the time required to identify areas that may be causing errors and the workload on the user.

[0073] This method analyzes the potential V(t) based on circuit theory, and therefore provides greater interpretability and explanation for identifying the cause of an anomaly than conventional methods that analyze based on empirical potential changes.

[0074] Furthermore, with conventional methods that perform analysis based on empirical potential changes, if a change occurs in the device configuration, it is necessary to collect new abnormal potential data and reconstruct the analysis algorithm associated with identifying the cause of the abnormality.Because this method is based on circuit theory, even if a change occurs in the device configuration, the algorithm can be changed simply by changing the equivalent circuit for the changed part and adjusting the threshold value of each parameter, making it highly robust against changes in device configuration.

[0075] Furthermore, the analyzer 100 of this embodiment can identify the cause of any abnormality in parallel with the measurement and calculation of ion concentration, thereby preventing a decrease in measurement throughput.

[0076] [Second embodiment] In the first embodiment, the simulated potential V obtained from the potential V(t) sim In contrast to this, in the second embodiment, the simulated potential V(t) is obtained from the potential V(t) and its parameters. sim This section explains how to detect signs of abnormalities from (t) and its parameters.

[0077] <Analyzer> The analyzer of the second embodiment may be the same as the analyzer 100 described in the first embodiment.

[0078] <Analysis method> Fig. 5 is a flowchart showing an analysis method according to the second embodiment. In Fig. 5, steps similar to those shown in Figs. 3 and 4 (first embodiment) are given the same reference numerals. Differences from the flowchart in Fig. 4 will be described in detail below.

[0079] First, in parallel with the operations of step S404 and subsequent steps executed after step S403, steps S403-1, S402-1, and S403-3 are successively executed by the circuit simulator unit 8. Step S403-3 may be the same as step S405-1 in FIG. 4, for example. Then, in step S501, C x (t), R x (t), V x (t), L x Changes in (t) over time are analyzed to detect signs of abnormalities.

[0080] At this time, the analysis of the change over time involves detecting change points and comparing with threshold information for sign detection. Specific calculations can be similar to, for example, S405-2 in FIG. 4 (first embodiment). That is, the memory stores the relationship between each parameter and related components, and when a parameter exceeds a threshold, it is possible to identify the related components and the abnormal state of the components that is thought to cause the threshold to be exceeded. When an abnormal state is identified, it can be said that a sign of the future occurrence of that abnormality has been detected. In this way, the analysis device 100 detects an abnormality sign based on the estimated electrical state change. Thereafter, in step S502, the detection result of the abnormality sign is displayed on the display unit 7.

[0081] <Technical effect> As described above, the analyzer of this embodiment generates a simulated potential V that approximates the potential V(t). sim (t) and V simBy analyzing the time-dependent changes in each parameter (t), it is possible to detect signs of equipment abnormalities, thereby alerting the user to potential sources of errors and disturbances before an abnormality occurs.

[0082] Furthermore, since maintenance can be planned in advance, unexpected shutdowns of the analyzer 100 can be avoided and maintenance work can be performed during periods when the operating rate of the analyzer 100 is low, thereby contributing to an improvement in measurement throughput.

[0083] [Third embodiment] In the first embodiment, a method was described for identifying the cause of an abnormality from parameters obtained by simulating the potentials obtained from the ion selective electrodes 101 to 103. In contrast, in the third embodiment, a method will be described for detecting the cause of an abnormality or a sign of an abnormality from simulating the potentials obtained at a plurality of electrodes provided in a plurality of flow paths, such as flow paths through which a sample solution and a reference solution pass.

[0084] <Analyzer> 6 shows the internal configuration of an analytical device 100 according to the third embodiment. In addition to ion selective electrodes 101 to 103 and a reference electrode 104, electrodes 601, 602, 603, and 604 are provided in the flow path through which the sample solution and reference solution flow. The outputs of each of these electrodes are connected to a circuit simulator unit 8. The respective potentials may be determined with reference to the ground potential (GND) within the device.

[0085] In the first embodiment, the ion selective electrodes 101 to 103 were provided at the same or adjacent positions in the flow path, but in this embodiment, any or all of the electrodes 601, 602, 603, and 604 are provided at positions in the flow path different from the ion selective electrodes 101 to 103, or at positions other than the flow path.

[0086] <Analysis method> The analysis device of the third embodiment uses the analysis method described in the first and second embodiments to identify the cause of an abnormal potential and detect signs of an abnormality using parameters obtained by simulating the potential of each electrode, including electrodes 601, 602, 603, and 604. That is, the analysis device 100 has multiple electrodes, and the circuit simulator unit 8 can simulate electrical signals for each of these multiple electrodes.

[0087] The number of equivalent circuit models may be one or more. For example, the storage unit 9 may store multiple equivalent circuit models, each corresponding to a different electrode. In this case, the circuit simulator unit 8 may acquire an approximate waveform for each equivalent circuit model, and the analysis device 100 may estimate an electrical state change by evaluating the similarity between each approximate waveform and the electrical signal of the corresponding electrode.

[0088] <Technical effect> The cause of an abnormality can be identified or signs of an abnormality can be detected by simulating the potential obtained from multiple electrodes provided in multiple flow paths, such as the flow paths through which the sample solution and reference solution pass. This improves the accuracy of abnormality determination by simulation compared to simulating the potential of an electrode at one location, enabling more accurate identification of the cause of an abnormality and detection of signs of an abnormality.

[0089] Furthermore, when multiple equivalent circuit models are used, a more precise model specialized for each electrode can be used.

[0090] [Fourth embodiment] In the fourth embodiment, an ammeter is provided to measure the current flowing through the flow path, and a method for identifying the cause of an abnormality or detecting a sign of an abnormality by simulating the measured current will be described.

[0091] <Analyzer> 7 shows the configuration of an analytical device 100 according to a fourth embodiment. It is equipped with ammeters 701, 702, 703, and 704 that measure the current flowing in the flow paths and conductors through which the sample solution and reference solution flow. Ammeters that can be used include moving coil, rectifier, electromotive force, induction, electrostatic, thermoelectric, and moving iron types. These ammeters are examples of means for measuring the current flowing in the flow paths, electrodes, or liquid delivery mechanisms.

[0092] <Analysis method> In addition to the analysis methods described in the first and second embodiments, the analysis device of the fourth embodiment acquires parameters by simulating the current of each ammeter. That is, the circuit simulator unit 8 can simulate the current based on an equivalent circuit model. The equivalent circuit model further includes a parameter I representing the current in addition to the one shown in FIG. x may be used with the addition of

[0093] The analysis device 100 estimates electrical state changes by simulating electrical signals (e.g., measured by the ion selective electrodes 101 to 103) and currents (e.g., measured by any or all of the ammeters 701, 702, 703, and 704) in the circuit simulator unit 8. Then, based on the estimation results, the cause of the potential abnormality is identified and signs of abnormality are detected.

[0094] <Technical effect> As described above, the analytical device of this embodiment can identify the cause of an abnormality or detect signs of an abnormality by simulating the current provided in the flow path through which the sample solution and the reference flow pass, in addition to simulating the potential. This makes it possible to supplement information that cannot be analyzed using only potential information with current information, improving the accuracy of abnormality determination through simulation and enabling more accurate identification of the cause of an abnormality and detection of signs of an abnormality.

[0095] [Fifth embodiment] In the fifth embodiment, a method for identifying the cause of an abnormality or detecting signs of an abnormality will be described, by measuring disturbances such as temperature, vibration, and static electricity in and around the flow path through which the sample liquid or reference liquid flows, and simulating the potential including the effects of the measured disturbances.

[0096] <Analyzer> 8 shows the configuration of an analytical device 100 according to the fifth embodiment. The analytical device 100 is provided with sensors 801, 802, 803, 804, and 805 that measure disturbances in and near the flow paths through which the sample liquid and reference liquid flow.

[0097] For example, the analytical device 100 includes a means for measuring the temperature (for example, the ambient temperature) of the flow path, the electrode, or the liquid transfer mechanism. The circuit simulator unit 8 can simulate an electrical signal based on the equivalent circuit model and the temperature.

[0098] Examples of disturbances measured by these sensors include temperature, vibration (acceleration and / or angular velocity), static electricity, etc. Parameters representing these disturbances are, for example, C in FIG. x (t), R x (t), V x (t), L x (t), etc., can be incorporated into an equivalent circuit. A specific method for converting the disturbances into these electrical parameters can be appropriately designed by a person skilled in the art. Furthermore, the positions at which sensors 801, 802, 803, 804, and 805 should be attached in the analysis device 100 to measure these disturbances can also be appropriately designed by a person skilled in the art.

[0099] <Analysis method> In addition to the analysis methods described in the first and second embodiments, the analysis device of the fifth embodiment uses parameters obtained by simulating the potential, including the effects of disturbances caused by sensors, to identify the cause of potential abnormalities and detect signs of abnormalities.

[0100] <Technical effect> As described above, the analytical device of this embodiment measures disturbances such as temperature, vibration, and static electricity in and around the flow paths through which the sample liquid and reference flow pass, and simulates the potential including the effects of the measured disturbances, thereby identifying the cause of an abnormality or detecting signs of an abnormality. This makes it possible to supplement disturbance information that cannot be analyzed using potential information alone with sensor information, improving the accuracy of anomaly determination through simulation and enabling more accurate identification of the cause of an abnormality and detection of signs of an abnormality.

[0101] [Sixth embodiment] In the sixth embodiment, a method for generating pseudo potential waveforms that reflect various states of the device when it is difficult to collect field data will be described.

[0102] <Analyzer> The analyzer of the sixth embodiment can be the same as the analyzer 100 described in the first to fifth embodiments. That is, the sixth embodiment can be implemented in combination with any of the first to fifth embodiments.

[0103] <Analysis method> First, the simulated potential V corresponding to the normal state is calculated by the method described in Example 1. sim (t) is calculated. Then, the simulated potential V sim (t) parameter is changed to a value outside the normal range, and a new simulated potential V is calculated using the changed parameter. sim (t) is calculated. This new simulated potential V sim (t) can be treated as an example of an abnormal potential waveform. In this way, the analysis device 100 generates a simulated signal that simulates a specific abnormal state.

[0104] This allows multiple examples of abnormal potential waveforms to be collected. It is also possible to create a dataset of abnormal potential waveforms by randomly inputting parameter values ​​within a predetermined range (but outside the normal range).

[0105] In addition, the simulated potential V when the parameter values ​​are randomly changed within the normal range sim By acquiring multiple (t), a data set of normal potential waveforms can also be created.

[0106] <Technical effect> As described above, the analysis device of this embodiment can generate examples of normal or abnormal potential waveforms. The generated potential waveforms can be used as substitutes for field data. This makes it possible to consider methods for analyzing abnormalities from waveform information even when it is difficult to collect field data. Specifically, it becomes possible to consider classification models for potential waveforms using supervised learning and to consider threshold settings used to identify the cause of abnormalities and detect signs of abnormalities. [Explanation of symbols]

[0107] 1...Electrolyte analysis unit 2...Electrical signal acquisition unit 3...Input section 4...Control unit 5...Concentration calculation section 6...Abnormality determination section 7…Display section 8...Circuit simulator section 9…Storage section 10…Potential analysis section 100…Analyzer 101-103...Ion selective electrodes (electrodes) 104...Reference electrode 105...Pinch valve (liquid transfer mechanism) 106... Vacuum suction nozzle (liquid delivery mechanism) 107... Sipper nozzle (liquid delivery mechanism) 108...Dilution liquid supply nozzle (liquid delivery mechanism) 109...Internal standard solution supply nozzle (liquid delivery mechanism) 110...Dilution tank (liquid transfer mechanism) 111...Waste liquid tank (liquid transfer mechanism) 112...Vacuum pump (liquid delivery mechanism) 120...Liquid junction (liquid transfer mechanism) 121~127 Solenoid valves (liquid transfer mechanism) 131... Syringe pump for internal standard solution (liquid delivery mechanism) 132...Dilution liquid syringe pump (liquid delivery mechanism) 133... Sipper syringe pump (liquid delivery mechanism) 141...Internal standard solution bottle (liquid delivery mechanism) 151...Dilution liquid bottle (liquid transfer mechanism) 161...Reference electrode solution bottle (liquid delivery mechanism) 170…Connection 601~604...Electrode 701~704…Ammeter 801~805...Sensor

Claims

1. An analytical device for analyzing characteristics of a conductive liquid, comprising: a flow path to which a liquid is supplied; an electrode provided in the flow channel and in contact with the liquid; a liquid delivery mechanism for introducing a liquid into the flow channel; an electrical signal acquiring unit for acquiring an electrical signal output from the electrode; a storage unit that stores a model that represents the liquid in the flow path, the electrodes, and the liquid delivery mechanism as an electric circuit; a circuit simulator unit capable of simulating the electrical signal based on the model; Equipped with An analytical device characterized in that the electrical state changes of the liquid in the flow path, the electrodes, and the liquid delivery mechanism are estimated by simulating the electrical signal in the circuit simulator section.

2. the model represents dynamic behavior of the liquid in the flow channel, the electrodes, and the liquid delivery mechanism based on an operation sequence; the storage unit stores a time chart of the operation sequence. The analytical device according to claim 1 .

3. 2. The analytical device of claim 1, wherein the electrodes comprise ion-selective electrodes that respond to the concentration of specific ions.

4. 2. The analytical device according to claim 1, wherein the model represents a change in circuit configuration due to an electrochemical phenomenon occurring at a solid-liquid interface or a liquid-liquid interface.

5. The analyzer according to claim 1 , wherein the cause of the abnormality is identified based on the estimated change in state.

6. The analyzer according to claim 1 , wherein a sign of an abnormality is detected based on the estimated change in state.

7. 2. The analysis device according to claim 1, wherein the state change is estimated based on the voltage, electrical resistance, capacitance, and inductance calculated by the simulation of the electrical signal and threshold information stored in the memory unit.

8. 2. The analysis device according to claim 1, further comprising a circuit simulator input unit that receives input of the model or parameters used in the simulation from the circuit simulator unit or the storage unit.

9. The analyzing device according to claim 1 , wherein the electrical signal acquiring unit, the circuit simulator unit, and the storage unit are connected via a communication network.

10. The analytical device has a plurality of the electrodes, the circuit simulator unit is capable of simulating the electrical signal for each of the electrodes; The analytical device according to claim 1 .

11. a means for measuring a current flowing through the flow path, the electrode, or the liquid delivery mechanism; the circuit simulator unit is capable of simulating the current based on the model; the analysis device estimates the state change by simulating the electrical signal and the current in the circuit simulator unit; The analytical device according to claim 1 .

12. a means for measuring a temperature related to the flow path, the electrode, or the liquid delivery mechanism; the circuit simulator unit is capable of simulating the electrical signal based on the model and the temperature; The analytical device according to claim 1 .

13. 2. The analyzer according to claim 1, wherein a simulated signal is generated to simulate a specific abnormal state.

14. A state detection method performed by an analyzer for analyzing characteristics of a conductive liquid, comprising: The analysis device a flow path to which a liquid is supplied; an electrode provided in the flow channel and in contact with the liquid; a liquid delivery mechanism for introducing a liquid into the flow channel; an electrical signal acquiring unit for acquiring an electrical signal output from the electrode; a storage unit that stores a model that represents the liquid in the flow path, the electrodes, and the liquid delivery mechanism as an electric circuit; a circuit simulator unit capable of simulating the electrical signal based on the model; Equipped with The state detection method includes: a step in which the electrical signal acquiring unit acquires a potential waveform based on a potential associated with the liquid supplied to the flow channel; the circuit simulator unit acquires an approximate waveform based on the model and the acquired potential waveform, and acquires parameters related to voltage, electrical resistance, capacitance, and inductance associated with the approximate waveform; a step in which the analysis device compares the acquired parameters with threshold information related to the parameters stored in the storage unit; a step of estimating an electrical state change of the analysis device based on the result of the comparing step; A state detection method comprising:

15. the model represents dynamic behavior of the liquid in the flow channel, the electrodes, and the liquid delivery mechanism based on an operation sequence; the storage unit stores a time chart of the operation sequence. The state detection method according to claim 14 .

16. 15. The state detection method according to claim 14, wherein the step of estimating an electrical state change of the analytical device includes a step of estimating an electrical state change of the liquid in the flow path, the electrodes, and the liquid delivery mechanism.

17. the storage unit stores a plurality of the models; the circuit simulator unit acquires the approximate waveform for each of the models; the analysis device estimates the state change by evaluating the similarity between each of the approximate waveforms and the electrical signal. The state detection method according to claim 14 .

18. The condition detection method according to claim 14 , further comprising a step in which the analysis device identifies a cause of the abnormality based on the estimated change in condition.

19. The condition detection method according to claim 14 , further comprising a step in which the analyzer detects a sign of abnormality based on the estimated change in condition.

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