Container for collecting test liquid and electrochemical measurement method

Abstract

To provide technology capable of electrochemically measuring analyte concentration stably and accurately.SOLUTION: A container for collecting test liquid comprises a function of collecting a fixed amount of test liquid, and a holding mechanism that detachably holds an electrochemical sensor equipped with a solid electrode, and is configured so that the test liquid can be collected with the electrochemical sensor attached to the holding mechanism. By collecting the test liquid with the electrochemical sensor attached, the solid electrode is immersed in the test liquid, and by holding the test liquid, the solid electrode is kept immersed in the test liquid.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a vessel for collecting a test liquid and an electrochemical measurement method. [Background technology]

[0002] It has been proposed to electrochemically measure the concentration of a test substance in a test solution by using an electrochemical sensor equipped with a working electrode having an electrode film made of a material containing diamond (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-281356 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to provide a technique for performing electrochemical measurement of a test substance concentration stably and with high accuracy. [Means for solving the problem]

[0005] According to one aspect of the present disclosure, A function of drawing up a fixed amount of test liquid; A holding mechanism for detachably holding an electrochemical sensor equipped with a solid electrode, The holding mechanism is configured to be capable of drawing up the test liquid in a state in which the electrochemical sensor is attached to the holding mechanism, With the electrochemical sensor attached, the test liquid is drawn up to immerse the solid electrode in the test liquid, and the test liquid is held to maintain the solid electrode immersed in the test liquid. A vessel for collecting the test liquid is provided.

[0006] According to another aspect of the present disclosure, preparing a container for collecting the test liquid; Attaching an electrochemical sensor to a holding mechanism of the container; a step of drawing a certain amount of test liquid into the container with the electrochemical sensor attached to the holding mechanism, and immersing a solid electrode mounted on the electrochemical sensor in the test liquid; holding the container so that the test liquid is stationary while maintaining the solid electrode immersed in the test liquid; measuring a concentration of a test substance in the test liquid electrochemically using the electrochemical sensor; An electrochemical measurement method is provided, comprising: Effect of the Invention

[0007] According to the present disclosure, it is possible to provide a technique for performing stable, highly accurate electrochemical measurement of the concentration of a test substance. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1(a) is a diagram showing an example of the schematic configuration of a container for drawing up a test liquid in one embodiment of the present disclosure, showing a longitudinal section of the container with an electrochemical sensor attached to a holding mechanism, and FIG. 1(b) is a diagram showing the container shown in FIG. 1(a) as viewed from above. [Diagram 2] FIG. 2(a) is a vertical cross-sectional view of a modified example of a scooping container according to one embodiment of the present disclosure, and FIG. 2(b) is a top view of the container shown in FIG. 2(a). [Diagram 3] FIG. 3(a) is a vertical cross-sectional view of yet another modified example of the sump container according to one embodiment of the present disclosure, and FIG. 3(b) is a top view of the container shown in FIG. 3(a). [Figure 4]Figure 4(a) is a diagram showing an example of the schematic configuration of a sump container in a modified example of one aspect of the present disclosure, and is a diagram showing a vertical cross-section of the container when viewed from the front with an electrochemical sensor attached to the holding mechanism, Figure 4(b) is a diagram showing a vertical cross-section of the container shown in Figure 4(a) when viewed from the side, Figure 4(c) is a diagram showing a vertical cross-section of the container shown in Figure 4(a) when viewed from the back (the side opposite to the front), and Figure 4(d) is a diagram showing the container shown in Figure 4(a) when viewed from the top. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The present disclosure has been made in consideration of the above-mentioned circumstances, and relates to a technique that enables stable and accurate electrochemical measurement of a test substance concentration in a test solution.

[0010] <One aspect of the present disclosure> Hereinafter, one embodiment of the present disclosure will be described with reference to the drawings.

[0011] (1) Configuration of the container for collecting the test liquid 1(a) and 1(b) show an example of the schematic configuration of a vessel 100 for sampling a test liquid (hereinafter also referred to as vessel 100) according to this embodiment. An example of the test liquid is ozone water in which ozone (O3) is dissolved in water (tap water, etc.). When the test liquid is ozone water, an example of the test substance to be measured is ozone dissolved in the ozone water (dissolved ozone).

[0012] The container 100 is configured to, for example, draw and hold a certain amount of test liquid from a flow path through which the test liquid flows, with an electrochemical sensor 20 (hereinafter also referred to as "sensor 20") attached to a holding mechanism 110 described below. The flow path is, for example, a conveying line (piping) through which ozone water generated by an ozone water generating device (not shown) flows. A specific embodiment of the container 100 will be described later.

[0013] The sensor 20 can be a three-electrode sensor equipped with a working electrode 21, a counter electrode 22, and a reference electrode 23, or a two-electrode sensor equipped with a working electrode 21 and a counter electrode 22. In this embodiment, an example in which the sensor 20 is a three-electrode sensor will be described. In this specification, the working electrode 21, the counter electrode 22, and the reference electrode 23 are also collectively referred to as a sensor electrode 26. In this manner, the sensor 20 is equipped with a plurality of electrodes, and the plurality of electrodes equipped with the sensor 20 are all solid electrodes (separately). The arrangement of the electrodes 21, 22, and 23 is not particularly limited, and can be appropriately changed depending on the test liquid, the test substance, and the shapes of the electrodes 21, 22, and 23. The shape, material, and the like of the electrodes 21, 22, and 23 equipped with the sensor 20 are appropriately determined depending on the test substance. When the test substance is dissolved ozone, at least the working electrode 21, preferably the working electrode 21, the counter electrode 22, and the reference electrode 23 can be diamond electrodes. A diamond electrode is an electrode having an electrode film made of a material containing diamond, for example, an electrode having an electrode film on its surface made of polycrystalline diamond doped with boron.

[0014] The sensor 20 is fitted with a measuring device 24 having, for example, a potentiostat function. The measuring device 24 is configured to be mountable on the sensor 20 and is electrically connected to the sensor electrode 26 via a conductor wiring (not shown) provided on the sensor 20. The measuring device 24 is configured to control the voltage applied to the sensor electrode 26 and to measure the current value (current value generated by the electrochemical reaction) flowing between the working electrode 21 and the counter electrode 22 in response to an electrochemical reaction generated at the working electrode 21 by the application of the voltage. For example, the measuring device 24 is configured to be able to generate an electrochemical reaction on the surface of the working electrode 21 by sweeping the potential of the working electrode 21 with the potential of the reference electrode 23 as a reference while applying a voltage between the working electrode 21 and the counter electrode 22 while bringing the sensor electrode 26 into contact with the test liquid, and to measure the current value flowing between the working electrode 21 and the counter electrode 22 at that time. The measuring device 24 has a display unit 25 and is configured to be able to display data indicating the concentration of the test substance obtained by measurement on the display unit 25. In addition, the measuring device 24 may be configured to be capable of transmitting data indicating the concentration of the test substance obtained by measurement to a computer equipped with communication functions (such as a smartphone, tablet, PC, etc.) via wireless communication means or wired communication means, etc.

[0015] (One embodiment of the container) One embodiment of the container 100 will now be described.

[0016] The container 100 is configured so that the test liquid can be drawn into the container 100 with the sensor 20 attached to the holding mechanism 110 described later. The container 100 is made of a material (chemically stable material) that does not corrode even when it comes into contact with the test liquid containing ozone. The container 100 is preferably made of a transparent or translucent resin. It is more preferable that the container 100 is made of a material with excellent heat insulation properties, so that the temperature of the test liquid drawn into the container 100 is less likely to change. Specific materials for the container 100 must be selected in consideration of the reactivity with the test liquid to be contained, and examples of such materials include UV-cured acrylic resin, silicone rubber, fluorine-based resin (polytetrafluoroethylene (PTFE), polychlorotrifluoroethylene (PCTFE), etc.), aromatic polyether ketone (PEEK) resin, ABS resin, polyethylene, polypropylene, polycarbonate, etc.

[0017] The container 100 is formed, for example, in a cylindrical shape, and an opening 101 (see FIG. 1(b)) is provided at the upper end of the container 100 as an inlet and outlet for the test liquid. The opening 101 is formed of a hole having a cross-sectional shape of a circle, an ellipse, a rectangle, or the like. The cross-sectional area (opening area) of the opening 101 can be adjusted as appropriate as long as it is large enough to allow at least the sensor 20 to pass through. The container 100 is formed with a space 102 that holds the sample liquid and brings it into contact with the sensor electrode 26, and the electrochemical measurement of the dissolved ozone concentration is performed in this space 102. Examples of electrochemical measurement include linear sweep voltammetry (LSV measurement), cyclic voltammetry (CVM measurement), and chronoamperometry (CA measurement).

[0018] The container 100 is provided with a holding mechanism 110 that holds the sensor 20 in a detachable (attachable and detachable) manner. The holding mechanism 110 holds the sensor 20 so that the sensor electrode 26 is immersed (the sensor electrode 26 is in contact with the test liquid) in the test liquid drawn into the container 100. The holding mechanism 110 is made of a material that will not corrode even when it comes into contact with the test liquid containing ozone. The holding mechanism 110 is formed in a shape that allows the sensor 20 to be held, for example, by fitting (the holding mechanism 110 is provided with a fitting holding portion 112 that fits and holds the sensor 20).

[0019] When measuring the ozone concentration in ozone water (concentration of dissolved ozone in water) electrochemically, if there is a flow (movement) in the test liquid (ozone water), the amount of the test substance (ozone) supplied to the sensor electrode 26 in the test liquid changes due to the movement of the test liquid, which may result in unstable concentration measurement results or low concentration measurement accuracy. For this reason, in order to measure the ozone concentration in ozone water electrochemically, it is necessary to measure the test liquid in a stationary state while contacting it with the sensor electrode 26. Note that "keeping the test liquid in a stationary state" here means that the test liquid is in a state where there is substantially no flow.

[0020] It has also been reported that the half-life of ozone (the time it takes for the ozone concentration to be reduced to half) is about twenty minutes even for stationary ozone water. For this reason, when electrochemically measuring the ozone concentration, it is necessary to measure the ozone concentration as soon as possible after drawing the ozone water into the container 100.

[0021] According to the container 100, by drawing up the test liquid with the sensor 20 attached to the holding mechanism 110, the sensor electrode 26 mounted on the sensor 20 can be filled with the test liquid, and the sensor electrode 26 can be immersed in the test liquid (hereinafter also referred to as the "immersed state of the sensor electrode 26"). According to the container 100, by holding the test liquid in the container 100 with the sensor 20 attached to the holding mechanism 110, the test liquid in the container 100 can be brought into a stationary state while maintaining the immersed state of the sensor electrode 26. Therefore, according to the container 100, with the sensor 20 attached to the holding mechanism 110, the stationary test liquid can be brought into contact with the sensor electrode 26 simply by drawing up the test liquid immediately before the concentration measurement. According to the container 100, the concentration measurement can be carried out immediately after the test liquid drawn into the container 100 is brought into a stationary state. As a result, even when the test substance is ozone, the concentration measurement can be carried out stably and with high accuracy.

[0022] The container 100 has a function of drawing a certain amount of the test liquid from a flow path through which the test liquid flows. For example, one or more drainage ports 103 are provided on the side of the container 100 at a certain height from the bottom, and the container 100 can thus have a function of drawing a certain amount of the test liquid. That is, the container 100 is configured to draw a certain amount of the test liquid by discharging the test liquid that is drawn in excess of the drawn test liquid (hereinafter also referred to as "excess liquid") from the drainage port 103. Note that instead of providing the drainage port 103, a scale line may be provided on the container 100, and the excess liquid may be discharged from the opening 101 or the like in accordance with the scale line, thereby drawing a certain amount of the test liquid. In this way, by providing the drainage port 103, the amount of the test liquid drawn into the container 100 can be always kept constant, and as a result, the amount of the test liquid when the concentration measurement is performed can be always kept constant. This makes it possible to prevent the measurement conditions from changing between different measurements when the concentration measurements are performed multiple times, i.e., to keep the measurement conditions constant between different measurements, thereby making it possible to perform the concentration measurements more stably and with higher accuracy.

[0023] The amount of the test liquid drawn into the container 100 can be adjusted by adjusting the installation position (height position) of the drainage outlet 103 on the side surface of the container 100. That is, the lower the installation position of the drainage outlet 103 (the closer to the bottom end of the container 100), the smaller the amount of the test liquid drawn, and the higher the installation position of the drainage outlet 103 (the closer to the top end of the container 100), the larger the amount of the test liquid drawn. The amount of the test liquid drawn and placed in the container 100 (the amount of the test liquid drawn and held in the container 100) can be, for example, 20 ml or more and 200 ml or less. This allows the test liquid to be drawn reliably with the sensor 20 attached to the holding mechanism 110, and allows the concentration measurement in the container 100 to be reliably performed with high accuracy. If the amount of the test liquid drawn and placed in the container 100 is less than 20 ml, the test liquid may not be able to fill the area around the sensor electrode 26, or the measurement accuracy of the concentration may be reduced. Furthermore, when the amount of test liquid to be drawn and placed in the container 100 exceeds 200 ml, it may not be possible to draw the test liquid with the sensor 20 attached to the holding mechanism 110. For example, when a measurer grasps one end (upper end) of the sensor 20 attached to the holding mechanism 110 (the measuring device 24 attached to the sensor 20) and draws the test liquid, the sensor 20 may fall off the holding mechanism 110 or the sensor 20 may fall off the measuring device 24.

[0024] The drainage port 103 is configured as a hole (opening) whose cross-sectional shape is circular, elliptical, rectangular, etc. The cross-sectional area (opening area) of the drainage port 103 can be appropriately adjusted according to the shape and size of the container 100, the amount of the test liquid to be drawn into the container 100, etc., as long as the cross-sectional area (opening area) of the drainage port 103 is large enough to discharge excess liquid.

[0025] A mechanism for suppressing the flow of the sample liquid drawn (hereinafter, also referred to as a "flow suppression mechanism") is preferably provided inside the container 100 so as not to interfere with the sensor 20 in a state where it is attached to the holding mechanism 110. For example, a plate-shaped member as the flow suppression mechanism is preferably provided (fixed) on at least one of the inner peripheral side surface and the bottom surface of the container 100 so as not to interfere with the sensor 20 in a state where it is attached to the holding mechanism 110. Examples of the flow suppression mechanism include a plate-shaped member 104a (see FIG. 1(a)) provided on the inner peripheral side surface of the container 100 along a direction from the lower end side to the upper end side of the container 100, a ring-shaped plate-shaped member 104b (see FIGS. 2(a) and 2(b)) provided on the inner peripheral side surface of the container 100, and a plate-shaped member (or rod-shaped member) 104c (see FIGS. 3(a) and 3(b)) provided on the bottom surface of the container 100. In this specification, the plate-like members 104a, 104b, and 104c serving as flow suppression mechanisms are also collectively referred to as plate-like member 104. It is sufficient that one or more plate-like members 104 are provided on at least one of the inner peripheral side surface and the bottom surface of the container 100.

[0026] As described above, by providing the flow suppression mechanism in the container 100, the test liquid drawn into the container 100 can be quickly brought to a stationary state. This shortens the time required from drawing the test liquid into the container 100 to starting the concentration measurement. Furthermore, by providing the flow suppression mechanism in the container 100, the test liquid drawn into the container 100 can be reliably brought to a stationary state, and the stationary state of the test liquid can also be reliably maintained. As a result, the concentration measurement can be performed more stably and with higher accuracy.

[0027] The holding mechanism 110 preferably includes a mechanism (positioning mechanism) configured to position the sensor electrode 26 at a fixed position in the container 100 when the sensor 20 is attached. For example, it is preferable that a member (positioning member) 111 configured to be abutted by the tip (lower end) of the sensor 20 is provided (fixed) as a positioning mechanism on at least one of the inner circumferential surface (inner circumferential side surface) and the bottom surface of the container 100. As shown in FIG. 1(a), the holding mechanism 110 holds the sensor 20 at a position where the tip (lower end) of the sensor 20 abuts (butts) against the positioning member 111, so that the sensor electrode 26 is positioned at a fixed position in the container 100. This makes it possible to position the sensor electrode 26 at a fixed position in the container 100 even when the sensor 20 is detached or replaced with another sensor 20 (of the same type). As a result, when concentration measurements are performed multiple times, it is possible to reliably prevent the measurement conditions from changing between different measurements, and it is possible to perform concentration measurements more stably and with higher accuracy.

[0028] Moreover, the holding mechanism 110 preferably includes a mechanism (fixing mechanism) for fixing the sensor electrode 26 at a fixed position in the container 100 when the sensor 20 is attached. That is, the holding mechanism 110 preferably holds the sensor 20 so that the sensor electrode 26 does not move during the concentration measurement. For example, even if the measurer performs the concentration measurement while holding the measuring device 24 attached to the sensor 20, the holding mechanism 110 preferably holds the sensor 20 so that the sensor electrode 26 does not move in the test liquid during the concentration measurement. As the fixing mechanism, for example, a member 113 (see FIG. 1(b)) for fixing the fitting holding part 112 of the sensor 20 in the holding mechanism 110 can be provided. As another example, as the fixing mechanism, a member for fixing the sensor 20 may be provided inside the container 100 (at least one of the inner circumferential side surface and the bottom surface). By fixing the sensor electrode 26 so as not to move during the concentration measurement, the concentration measurement can be performed more stably and with high accuracy.

[0029] (2) Electrochemical measurement method A method for electrochemically measuring the concentration of a test substance in a test liquid using the above-mentioned container 100 will now be described.

[0030] First, the above-mentioned container 100 is prepared (container preparation). Then, the sensor 20 is attached to the holding mechanism 110 included in the container 100 (attaching the electrochemical sensor). At this time, the sensor 20 is attached to the holding mechanism 110 so that the sensor electrode 26 mounted on the sensor 20 is located inside the container 100, that is, so that the sensor electrode 26 is immersed in the test liquid when the test liquid is drawn into the container 100. Also, at this time, the sensor 20 is attached to the holding mechanism 110 so that the lower end of the sensor 20 abuts against a positioning member 111 provided on at least one of the inner circumferential side surface and the bottom surface of the container 100.

[0031] Once the attachment of the sensor 20 is complete, the measuring device 24 is attached to the sensor 20 and the sensor 20 and the measuring device 24 are electrically connected.

[0032] With the sensor 20 attached to the holding mechanism 110, for example, ozone water is drawn as a test liquid from a flow path through which the ozone water flows (drawing of the test liquid). The measurer can draw the test liquid while, for example, holding the measuring device 24 attached to the sensor 20. When drawing the test liquid, any test liquid that has been drawn in excess (excess liquid) of the drawn test liquid is discharged from the drainage port 103. As a result, a certain amount of test liquid (for example, 20 ml or more and 200 ml or less) is drawn into the container 100. Furthermore, as the test liquid is drawn into the container 100, the sensor electrode 26 is filled with the test liquid, and the sensor electrode 26 is immersed in the test liquid.

[0033] Once the sampling of the test liquid is completed and the sensor electrode 26 is immersed in the test liquid, the container 100 is held so that the sampled test liquid is stationary while maintaining the immersion of the sensor electrode 26 (holding the container).

[0034] When the test liquid in the container 100 becomes stationary, the test liquid is maintained in a stationary state while electrochemically measuring the concentration of the test substance contained in the test liquid (electrochemical measurement). Specifically, while maintaining the stationary test liquid in contact with the sensor electrode 26, a voltage is applied between the working electrode 21 and the counter electrode 22 by controlling the voltage applied from the measuring device 24 to the sensor electrode 26, and the potential of the working electrode 21 is swept based on the potential of the reference electrode 23, and the current value flowing between the working electrode 21 and the counter electrode 22 at that time is measured. After the current value is measured by the measuring device 24, a process required for calculating the ozone concentration is performed based on the measured current value by a computer device or the like.

[0035] When the electrochemical measurement is completed, the measuring device 24 is removed from the sensor 20, and the sensor 20 is removed from the holding mechanism 110. Then, the test liquid in the container 100 is discharged from the opening 101, etc. Then, if necessary, the inside of the container 100 after the test liquid has been discharged is cleaned, and the removed sensor 20 is cleaned, etc. Note that the test liquid in the container 100 may be discharged with the measuring device 24 still attached.

[0036] (3) Effects According to this aspect, one or more of the following effects can be obtained.

[0037] (a) With the container 100, with the sensor 20 attached to the holding mechanism 110, simply drawing up the test liquid immediately before carrying out the concentration measurement can bring the test liquid in a stationary state into contact with the sensor electrode 26. Furthermore, with the container 100, the concentration measurement can be carried out immediately after the test liquid drawn into the container 100 has reached a stationary state. As a result, even when the test substance is ozone, it is possible to carry out the concentration measurement stably and with high accuracy.

[0038] (b) The container 100 has a function of drawing up a constant amount of test liquid, i.e., the amount of test liquid drawn into the container 100 is always constant, so that the amount of test liquid when performing concentration measurement can always be kept constant. This makes it possible to keep the measurement conditions constant between different measurements when performing concentration measurements multiple times, and as a result, it becomes possible to perform concentration measurements more stably and with higher accuracy.

[0039] (c) By providing a flow suppression mechanism inside the container 100, the test liquid drawn into the container 100 can be quickly and reliably brought to a stationary state. In addition, the stationary state of the test liquid can be reliably maintained. As a result, it becomes possible to perform concentration measurement more stably and with higher accuracy.

[0040] (d) The holding mechanism 110 includes a mechanism (positioning mechanism) for holding the sensor electrode 26 at a fixed position in the container 100 when the sensor 20 is attached, so that the sensor electrode 26 can be positioned at a fixed position in the container 100 even if the sensor 20 is detached or replaced. This ensures that the measurement conditions are consistent between different measurements when concentration measurements are performed multiple times. As a result, concentration measurements can be performed more stably and with higher accuracy.

[0041] (e) The holding mechanism 110 is formed in a shape that allows the sensor 20 to be fitted and held, which makes it possible to easily attach and detach the sensor 20 to and from the holding mechanism 110. Furthermore, the holding mechanism 110 is provided with a mechanism for fixing the sensor electrode 26 to a fixed position in the container 100 when the sensor 20 is attached, i.e., the holding mechanism 110 holds the sensor 20 so that the sensor electrode 26 does not move during concentration measurement, which makes it possible to perform the concentration measurement with even greater stability and accuracy.

[0042] (f) Since the amount of test liquid placed in container 100 is between 20 ml and 200 ml, it is possible to reliably draw up the test liquid while sensor 20 is attached to holding mechanism 110, and it is possible to perform concentration measurement in container 100 with even greater stability and accuracy.

[0043] (4) Variations This aspect can be modified as in the following modified examples. In the following description of the modified examples, the same components as those in the above aspect are denoted by the same reference numerals, and the description thereof will be omitted. The above aspect and the following modified examples can be combined in any combination.

[0044] For example, the container 100 can be modified as follows. The container 100A according to this modification is configured so that the sensor electrode 26 mounted on the sensor 20 and the electrode provided on the cradle are electrically connected by placing the container 100A on a cradle connected to the measuring device 24. An example of a schematic configuration diagram of the container 100A according to this modification is shown in FIG. 4(a) to FIG. 4(d). As shown in FIG. 4(a) to FIG. 4(d), the container 100A further includes an electric wiring 120 and a metal electrode 121 in addition to a function of drawing up a certain amount of test liquid from a flow path through which the test liquid flows and a holding mechanism 110. Note that FIG. 4(a) to FIG. 4(d) show the container 100A without the drainage port 103, the flow suppression mechanism, the positioning mechanism, the fixing mechanism, and the like. However, it goes without saying that the container 100A may also include these, like the above-mentioned container 100.

[0045] The electrical wiring 120 is configured to be electrically connectable to the sensor electrode 26. For example, the electrical wiring 120 is configured to be electrically connectable to the sensor electrode 26 (the working electrode 21, the counter electrode 22, and the reference electrode 23) via a conductor wiring (not shown) provided in the sensor 20. The electrical wiring 120 is covered with a resin material or the like to be insulated. The metal electrode 121 is provided on the outer surface (the outer peripheral side surface or the outer peripheral bottom surface) of the container 100A and is connected to the electrical wiring 120. Note that Figs. 4(a) to 4(d) show an example in which the metal electrode 121 is provided on the outer peripheral side surface of the container 100A. The metal electrode 121 is configured to be electrically connectable to an electrode provided in a cradle (not shown) to which the measuring device 24 (measuring device) is connected.

[0046] The container 100A is configured such that, by mounting the sensor 20 on the holding mechanism 110, the sensor electrode 26 and the metal electrode 121 are electrically connected via the electrical wiring 120 and the conductor wiring provided on the sensor 20. The container 100A is also configured such that, by placing the container 100A on a cradle connected to the measuring device 24, the sensor electrode 26 and the electrode provided on the cradle are electrically connected via the electrical wiring 120 and the conductor wiring (not shown) provided on the sensor 20, and as a result, the sensor electrode 26 and the measuring device 24 are electrically connected.

[0047] A method for electrochemically measuring the concentration of a test substance in a test liquid using the container 100A will be described below. First, the container 100A having the above-mentioned configuration is prepared (preparation of container). Then, the sensor 20 is attached to the holding mechanism 110 provided in the container 100A (attachment of electrochemical sensor). By attaching the sensor 20 to the holding mechanism 110, the sensor electrode 26 and the metal electrode 121 are electrically connected via the electrical wiring 120 and the conductor wiring provided in the sensor 20. After the attachment of the sensor 20 is completed, a certain amount of the test liquid is drawn with the sensor 20 attached to the holding mechanism 110 (drawing of test liquid). After the drawing of the test liquid is completed, the container 100A with the sensor 20 attached to the holding mechanism 110 and the test liquid held therein is placed on a cradle to which the measuring device 24 is connected (placement on cradle). At this time, the container 100A is placed on the cradle so that the metal electrode 121 and the electrode of the cradle are electrically connected. As a result, the sensor electrode 26 and the electrode of the cradle are electrically connected via the metal electrode 121, the electrical wiring 120, and the conductor wiring provided on the sensor 20, and as a result, the sensor electrode 26 and the measuring device 24 are electrically connected, and electrochemical measurement (such as applying a voltage to the sensor electrode 26) can be performed. The container 100A is placed on the cradle, and when the test liquid drawn while maintaining the immersion state of the sensor electrode 26 becomes stationary, electrochemical measurement is performed. That is, when the test liquid in the container 100A becomes stationary, the concentration of the test substance contained in the test liquid is electrochemically measured while maintaining the stationary state of the test liquid (electrochemical measurement).

[0048] In the container 100A as well, with the sensor 20 attached to the holding mechanism 110, the test liquid in a stationary state can be brought into contact with the sensor electrode 26 simply by drawing up the test liquid immediately before performing the concentration measurement. Also, in the container 100A as well, the concentration measurement can be performed immediately after the test liquid drawn into the container 100A becomes stationary. As a result, even when the test substance is ozone, it is possible to perform the concentration measurement stably and with high accuracy. In this way, the same effects as those of the above-mentioned embodiment can be obtained in this modified example as well.

[0049] Furthermore, according to the configuration of container 100A, after the test liquid is drawn up with sensor 20 attached to holding mechanism 110, electrochemical measurement can be performed simply by placing container 100A on a cradle to which measuring device 24 is connected.

[0050] <Other aspects> The above describes the aspects and modifications of the present disclosure in detail. However, the present disclosure is not limited to the above aspects and modifications, and various modifications are possible without departing from the spirit and scope of the present disclosure.

[0051] For example, in the above-mentioned aspects and variations, the test liquid is ozone water and the test substance is dissolved ozone in the ozone water, but this is not necessarily limited to this and can be applied to other types of test liquids and specific components as long as the concentration can be measured using an electrochemical reaction.

[0052] <Preferred aspects of the present disclosure> Preferred aspects of the present disclosure will be described below.

[0053] (Appendix 1) According to one aspect of the present disclosure, A function of drawing up a fixed amount of test liquid; A holding mechanism for detachably holding an electrochemical sensor equipped with a solid electrode, The holding mechanism is configured to be capable of drawing up the test liquid in a state in which the electrochemical sensor is attached to the holding mechanism, With the electrochemical sensor attached, the test liquid is drawn up to immerse the solid electrode in the test liquid, and the test liquid is held to maintain the solid electrode immersed in the test liquid. A vessel for collecting the test liquid is provided.

[0054] (Appendix 2) The container according to claim 1, preferably comprising: One or more drainage ports are provided on a side surface of the container at a certain height from the bottom surface, The test liquid is configured to be drawn up in a constant amount by discharging the test liquid drawn up in excess from the drain port.

[0055] (Appendix 3) The container according to claim 1 or 2, preferably A mechanism for suppressing the flow of the test liquid is provided so as not to interfere with the electrochemical sensor in a state where it is attached to the holding mechanism.

[0056] (Appendix 4) The container according to claim 3, preferably comprising: The mechanism for suppressing the flow of the test liquid is a plate-like member fixed to at least one of the inner circumferential side surface and the bottom surface of the container.

[0057] (Appendix 5) The container according to any one of appendixes 1 to 4, preferably The holding mechanism includes a positioning mechanism configured to position the solid electrodes in fixed positions when the electrochemical sensor is attached.

[0058] (Appendix 6) The container according to claim 5, preferably comprising: the positioning mechanism is a member that is fixed to at least one of an inner circumferential surface and a bottom surface of the container and is configured to come into contact with a tip of the electrochemical sensor; The holding mechanism is configured to hold the electrochemical sensor at a position where the tip of the electrochemical sensor abuts against the member, thereby positioning the solid electrode in a fixed position.

[0059] (Appendix 7) The container according to any one of appendixes 1 to 6, preferably It is formed in a cylindrical shape with an opening at the top.

[0060] (Appendix 8) The container according to any one of appendices 1 to 7, preferably The amount of the test liquid to be pumped and stored is 20 ml or more and 200 ml or less.

[0061] (Appendix 9) The container according to any one of appendixes 1 to 8, preferably The holding mechanism is formed in a shape capable of fitting and holding the electrochemical sensor, and includes a mechanism for fixing the solid electrode in a fixed position when the electrochemical sensor is attached.

[0062] (Appendix 10) The container according to any one of appendixes 1 to 9, preferably It is made of transparent or translucent resin.

[0063] (Appendix 11) According to another aspect of the present disclosure, A step of preparing a container for collecting a test liquid according to any one of appendix 1 to 10; Attaching an electrochemical sensor to a holding mechanism of the container; a step of drawing a certain amount of test liquid into the container with the electrochemical sensor attached to the holding mechanism, and immersing a solid electrode mounted on the electrochemical sensor in the test liquid; holding the container so that the test liquid is stationary while maintaining the solid electrode immersed in the test liquid; measuring a concentration of a test substance in the test liquid electrochemically using the electrochemical sensor; An electrochemical measurement method is provided, comprising:

[0064] (Appendix 12) According to yet another aspect of the present disclosure, A function of drawing up a fixed amount of test liquid; a holding mechanism for detachably holding an electrochemical sensor equipped with a solid electrode; an insulating coated electrical wiring configured to be connectable to the solid electrode when the electrochemical sensor is attached to the holding mechanism; A metal electrode provided on the outer peripheral surface and connected to the electrical wiring; Equipped with The electrochemical sensor is attached to the holding mechanism, so that the solid electrode and the metal electrode are electrically connected via the electrical wiring. The holding mechanism is configured to be capable of drawing up the test liquid in a state in which the electrochemical sensor is attached to the holding mechanism, The test liquid is pumped up while the electrochemical sensor is attached to the solid electrode, thereby immersing the solid electrode in the test liquid, and the test liquid is held in place to maintain the solid electrode immersed in the test liquid. A vessel for collecting the test liquid is provided.

[0065] (Appendix 13) According to yet another aspect of the present disclosure, Providing a vessel for collecting the test liquid described in Appendix 12; a step of mounting an electrochemical sensor on a holding mechanism of the container and electrically connecting a solid electrode mounted on the electrochemical sensor and a metal electrode of the container via an electrical wiring of the container; a step of drawing a certain amount of test liquid into the container with the electrochemical sensor attached to the holding mechanism, and immersing the solid electrode in the test liquid; a step of mounting the electrochemical sensor on the holding mechanism and placing the container holding the test liquid on a cradle connected to an electrochemical measurement device, and electrically connecting the metal electrode and an electrode provided on the cradle; a step of keeping the test liquid stationary while maintaining the solid electrode immersed in the test liquid; measuring a concentration of a test substance in the test liquid electrochemically using the electrochemical sensor; An electrochemical measurement method is provided, comprising: [Explanation of symbols]

[0066] 20 Electrochemical Sensors 100,100A Container for collecting test liquid 103 Drain 104a,104b,104c Flow suppression mechanism 110 Retention mechanism 111 Positioning mechanism 113 Fixing member

Claims

1. A function of drawing up a fixed amount of test liquid; A holding mechanism for detachably holding an electrochemical sensor equipped with a solid electrode, The holding mechanism is configured to be capable of drawing up the test liquid in a state in which the electrochemical sensor is attached to the holding mechanism, With the electrochemical sensor attached, the test liquid is drawn up to immerse the solid electrode in the test liquid, and the test liquid is held to maintain the solid electrode immersed in the test liquid. A container for collecting the test liquid.

2. One or more drainage ports are provided on a side surface of the container at a certain height from the bottom surface, 2. The test liquid pick-up container according to claim 1, configured to pick up a constant amount of the test liquid by discharging an excess of the test liquid picked up from the drain port.

3. 3. The sample liquid scooping container according to claim 1, wherein the mechanism for suppressing the flow of the sample liquid is provided so as not to interfere with the electrochemical sensor in a state where it is attached to the holding mechanism.

4. 4. The sample liquid scooping vessel according to claim 3, wherein the mechanism for suppressing the flow of the sample liquid is a plate-like member fixed to at least one of an inner peripheral side surface and a bottom surface of the vessel.

5. 3. The sample liquid pick-up container according to claim 1, wherein the holding mechanism includes a positioning mechanism configured to position the solid electrode in a fixed position when the electrochemical sensor is attached.

6. the positioning mechanism is a member that is fixed to at least one of an inner circumferential surface and a bottom surface of the container and is configured to come into contact with a tip of the electrochemical sensor; The holding mechanism is configured to hold the electrochemical sensor at a position where the tip of the electrochemical sensor abuts against the member, thereby positioning the solid electrode in a fixed position. A vessel for collecting a test liquid according to claim 5.

7. 3. The vessel for scooping up a test liquid according to claim 1, which is formed in a cylindrical shape having an opening at the top.

8. 3. The test liquid scooping container according to claim 1, wherein the amount of the test liquid scooped and stored is 20 ml or more and 200 ml or less.

9. The holding mechanism is formed in a shape capable of fitting and holding the electrochemical sensor, and includes a mechanism for fixing the solid electrode in a fixed position when the electrochemical sensor is attached.

3. A vessel for collecting a test liquid according to claim 1 or 2.

10. 3. The sample liquid scooping container according to claim 1 or 2, which is made of a transparent or translucent resin.

11. A step of preparing a vessel for collecting a test liquid according to claim 1; Attaching an electrochemical sensor to a holding mechanism of the container; a step of drawing a certain amount of test liquid into the container with the electrochemical sensor attached to the holding mechanism, and immersing a solid electrode mounted on the electrochemical sensor in the test liquid; holding the container so that the test liquid is stationary while maintaining the solid electrode immersed in the test liquid; measuring a concentration of a test substance in the test liquid electrochemically using the electrochemical sensor; The electrochemical measurement method according to claim 1,

Images