JPS6239757A - Method and instrument for measuring ion activity - Google Patents

Abstract

PURPOSE:To measure the activity of one kind or plural kinds of ions by using one measuring instrument, by respectively applying a reference liquid and a liquid to be inspected to the surfaces of the ion selection layers of at least a pair of sheet like ion selection electrodes separated electrically to each other. CONSTITUTION:Sheet like ion selection layers 115, liquid imparting parts for imparting a reference liquid and a liquid to be inspected to the surfaces of respective selection layers 115 and a bridge 19 for bringing both liquids to a mutually electrical continuity state are provided to the uppermost part. The electrodes 11a-11c are arranged so as to direct the selection layers 115 to the downside and the reference liquid and the liquid to be inspected imparted from above is once moved to the parts below the surfaces of the selection layers 115. Thereafter, said liquids are raised to the surface positions of the selection layers 115 from the surfaces of the selection layers 115 through liquid rising guide passages 15a-15c of which the top parts of the side walls are set apart so as to have a gap accompanying no generation of a capillary phenomenon to the surfaces of the selection layers 115 to impart both liquids to the surfaces of the selection layers 115. Subsequently, the potential difference between electrodes 11a-11c is measured in such a state that both liquids are brought to a mutually electrical continuity state by the bridge 19.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention utilizes botensiometry to measure the activity (or concentration) of specific ions in aqueous liquids, particularly biological fluids (blood, urine, saliva, etc.). [Background of the Invention] Liquids (tap water, river water, sewage, industrial wastewater, etc.) Measures the activity of specific ions contained in droplets of biological body fluids (whole blood, plasma, serum, urine, saliva, etc.) using a sheet-shaped ion activity measurement device. A method to do this is already known.

That is, a reference liquid and a test liquid are applied to the surface of each ion-selective layer of a pair of sheet-like ion-selective electrodes that are electrically separated from each other and have an ion-selective layer on the top, and then the two liquids are connected to each other by a bridge. This method measures the ion activity of the test liquid by measuring the potential difference between each ion selection electrode in an electrically conductive state.

An example of such an ion activity measuring device is:

Japanese Patent Application Laid-open No. 52-142588 (US 405338)
1) (US stands for United States patent), Japanese Patent Publication No. 584148
Publication No. (US4273639), JP 58-2118
For example, the ion activity measuring device described in US Pat. No. 4,437,970 can be mentioned.

These ion activity measuring instruments basically have a pair of sheet-like ion-selective electrodes arranged with the ion and selective layer facing upward, and a liquid spotting hole 1:1 (standard solution and exposed) on top of the electrodes. The reference solution and test solution are applied from above onto each ion-selective layer using a pipette, etc., through the solution spotting holes, and both ions are applied. A method is used to measure ion activity by measuring the potential difference generated between selected electrodes. Furthermore, as an improved version of the ion activity measurement device described above, a plurality of ion selection electrode pairs are incorporated into the ion activity measurement device, and the reference solution and test solution are applied once each. There are also known devices that allow the activities of multiple types of ions to be measured by adjusting the number of ions.

The method for measuring ion activity using a pair of sheet-like ion-selective electrodes as described above is a simple and simple method, but according to the inventor's study, there are various problems in manufacturing the measuring instrument and performing the measuring operation. It turned out there was a problem.

The first problem is that the ion-selective layer is easily damaged by the tip of the pipette normally used to apply the reference and test solutions. Since the ion-selective layer is not a solid but a jelly-like membrane, it is easily scratched when the tip of a pipette comes into contact with its surface.
Alternatively, such deterioration of the shape of the ion selective layer, which causes deformation, causes measurement errors, and in extreme cases, measurement becomes impossible.

The second problem is that the silver chloride layer of the ion-selective electrode easily deteriorates. Most ion-selective electrodes use a silver/silver chloride electrode (half cell) as an internal reference electrode, but in that case, if the ion activity measurement device is left in a bright room, light incident from the liquid spotting hole will The silver chloride layer tends to change in quality, and as a result, the electrode tends to deteriorate.

A third problem is that the terminal (probe) for measuring the potential difference generated between the ion selection electrodes is easily contaminated.

A sheet-like ion-selective electrode is generally used in the form of an electrode formed on the surface of a plastic sheet support. To measure ion activity using an ion-selective electrode, it is necessary to measure the potential difference between a pair of ion-selective electrodes as described above. For this purpose, an area for electrical connection (for example, an extension of the silver layer) is provided at the end of the conductive site of the ion-selective electrode (the silver layer in the case of a silver/silver chloride electrode). Then, the potential difference is measured by bringing a terminal of a separately prepared potential difference measuring device into contact with that region. In this case, if the arrangement is such that the normal ion selective layer is on the upper side, the surface of the electrical connection area will naturally also be directed upward, and the terminal of the potentiometer will be in contact with the surface of the electrical connection area from above. Placed. Therefore, there is a problem in that the potential difference measurement terminal is likely to be contaminated by the reference liquid or test liquid applied from above.

Fourth, there is a problem that the measurement system of the potentiometric measuring device used in combination with the ion activity measuring device tends to be complicated. In other words, 1. If the arrangement is such that the normal ion selective layer is on the upper side, the surface of the electrical connection area is also directed upward as described above, and the terminal of the potentiometric measuring device contacts the surface of the electrical connection area from above. It is arranged like this. For this reason, if wiring of the potential difference measurement system is to be carried out without difficulty, the wiring needs to be carried out upward or towards the sides. On the other hand, it is advantageous to place the measuring instrument of the potentiometric measuring device below the ion activity measuring instrument, in order to avoid contact with the reference liquid and test liquid, and to save space occupied by the device. becomes. Therefore, when using a conventional ion activity measurement device that assumes an operation in which the ion selective layer is placed on the north side and a reference solution or test solution is applied thereon, the measurement system of the potentiometric measurement device used in combination with it The measurement system tends to become complicated, and the measurement system requires a large amount of space.

Fifth, in the conventional method, when a large number of test items are measured simultaneously, there is a difference in the contact time of the reference liquid or test liquid to each electrode surface, which is one of the causes of measurement errors.

[Object of the Invention] An object of the present invention is to provide a method for measuring the activity of one or more types of ions using one instrument, and an ion activity measuring instrument that can be advantageously used in the measurement method. It is in.

In particular, the purpose of the present invention is to provide an ion activity measurement method that can solve all of the problems listed in L that are likely to occur in hitherto known ion activity measurement methods and measuring instruments used therefor, and An object of the present invention is to provide an ion activity measuring instrument that can be advantageously used in a measuring method.

[Summary of the Invention] The present invention provides a method for applying a reference liquid and a test liquid to the surface of each ion-selective layer of at least a pair of sheet-like ion-selective electrodes that are electrically separated from each other and that have an ion-selective layer on the top. In a method for measuring the ionic activity of a test liquid, the method comprises: (1) measuring the potential difference between each ion selection electrode in a state in which both liquids are electrically connected to each other through a bridge;

Each sheet-shaped ion-selective electrode is arranged so that the ion-selective layer is on the lower side, and each liquid applied from the J: direction is moved to a position below the surface of the ion-selective layer, and then the ion-selective layer is Each liquid is raised to the surface position of the ion selective layer through a liquid rising guide path in which the top of the side wall is separated from the surface of the ion selective layer by a gap that does not cause capillarity to the surface. The method of measuring ion activity is characterized in that each liquid is applied to the surface of an ion selective layer.

The method for measuring ion activity described above consists of at least a pair of sheet-like ion-selective electrodes that are electrically separated from each other and have an ion-selective layer at the outermost part, and a reference liquid and a sample to be detected on the surface of each ion-selective layer. In an instrument for measuring ion activity of a test liquid, which has a liquid application part for applying a liquid and a bridge for electrically conducting both liquids, each sheet-shaped ion-selective electrode has an ion-selective layer on the bottom side. The liquid applying section includes an upper liquid applying opening, a descending passageway that moves the liquid to a position below the surface of the ion selective layer, and a horizontal direction that moves the liquid immediately below the surface of the ion selective layer. and a liquid rising guide path for raising the liquid to the surface position of the ion selective layer (however, the top of the side wall of this liquid rising guide path must be accompanied by the occurrence of capillary action with respect to the surface of the ion selective layer). This can be advantageously carried out by using an ion activity measuring instrument characterized in that the ion activity measuring device includes the following:

In this specification, a gap in which no capillary phenomenon occurs with respect to the surface of the ion-selective layer is defined as a gap in which the liquid moves against its own weight to fill the gap between the ion-selective layer and the top of the side wall of the liquid upward guide path. means a gap larger than the gap that can be penetrated. The above-mentioned gap varies depending on the surface tension of the liquid and the surface condition of the material of the contacting member, but is generally 50 #Lm or more.

[Effects of the Invention] By using the ion activity measuring method and measuring instrument of the present invention, the above-mentioned problems that tend to occur in hitherto known ion activity measuring methods and measuring instruments used therein can be solved all at once. can be achieved.

That is, by using the ion activity measuring method and measuring instrument of the present invention, physical deterioration due to contact with the pipette tip of the ion selective layer of the ion selective electrode, and chemical deterioration of the electrode portion of the ion selective electrode due to exposure to light can be avoided. can be effectively avoided.

In addition, in the ion activity measuring method and measuring instrument of the present invention, the surface of the electrical connection area is placed facing downward, so wiring for potential difference measurement downward to the liquid supply system above is easily realized. I'll do it. Therefore.

Contamination of the potential difference measuring terminal is prevented, and the measurement system of the potential difference measuring device can be simplified.

Furthermore, in the ion activity measuring method and measuring instrument of the present invention,
Since the top of the side wall of the liquid rising guide path is separated from the surface of the ion selective layer by a gap that does not cause capillary action, an oily substance is used as a plasticizer in the ion selective layer. In this case, there is no risk that these substances will come into contact with or flow out to the top of the side wall, resulting in uneven distribution, and the spaces on the liquid rising guide paths adjacent to each other through the above-mentioned gap are open at least in relation to each other. Therefore, the ion activity measurement method and measuring instrument of the present invention are unlikely to cause measurement errors caused by the generation of air bubbles. It also has the effect of

Furthermore, in the ion activity measuring method and measuring instrument of the present invention, the presence of the liquid rising guide path makes the contact area and contact time of the reference liquid or test liquid to each electrode surface uniform.

The ion activity measuring device of the present invention also has the advantage that the sheet-like ion selection electrode and the device frame are less likely to be distorted during manufacturing and assembly of the device. As a result, an ion activity measuring instrument capable of measuring ion activity with high accuracy is obtained.

Detailed Description of the Invention J The ion activity measuring method and measuring instrument of the present invention will be described in detail with reference to the ion activity measuring instrument shown in the accompanying drawings.

FIG. 1 is a perspective view showing an example of the ion activity measuring instrument of the present invention. FIG. 1A is an elevational sectional view taken along the line II of the ion activity measuring device shown in FIG. 1, and FIG. 1B is a bottom view of the ion activity measuring device shown in FIG. FIG. 1C is an enlarged view of the circled portion X of the elevational cross-sectional view shown in FIG. 1A, and FIG. FIG. 3 is a diagram schematically showing the state of adhesion.

FIG. 2 is a diagram showing each constituent member separated in order to explain in detail each member constituting the ion activity measuring instrument shown in FIG. 1.

The ion activity measurement device of the embodiment shown in these figures includes three pairs of sheet-like ion selective electrodes each having an ion selective layer on the top (the pair of ion selective electrodes are connected to a reference liquid electrically separated from each other). 11a, llb, and llc, each consisting of a combination of an ion-selective electrode for the test liquid and an ion-selective electrode for the test liquid, are arranged so that the ion-selective layer is on the lower side. In this arrangement, the sheet-like ion-selective electrode is constructed such that, as shown in FIG.
, electrolyte layer 114. Each layer of the ion selection layer 115 is laminated.

The sheet-like ion-selective electrode configured in this manner is placed in an inverted state within the measurement instrument.

As is clear from FIG. 1A, the liquid attachment part for applying the reference liquid and the test liquid to the surface of the ion selection layer of the ion selection electrode has an upper liquid application opening 12 and an ion selection part for applying the liquid to the surface of the ion selection layer of the ion selection electrode. A descending passage 13 for moving the layer to a position below the surface.
A horizontal passage 14 for moving the liquid horizontally directly below the surface of the ion-selective layer, and a liquid rising guide path 15a, 1 for moving the liquid from a position directly below each ion-selective electrode.
It is composed of 5b and 15c. Liquid rising guide path 15
a, 15b, and 15c, the tops of the side walls are separated from the surface of the ion-selective layer by gaps that do not cause capillarity to the surface of the ion-selective layer. That is, as shown in FIGS. 1A and 1C, the liquid ascending guide path 15a.

At the top of 15b and 15c, there is an opening 2 larger than the guide path.
5 is provided. By providing this space, as schematically shown in FIG. 1D, the liquid rising after passing through the horizontal passage 14 can select ions without causing capillary action on the surface of the ion-selective layer. Contact the electrode surface. Therefore, it is possible to prevent the liquid from spreading in the horizontal direction on the surface of the ion selective layer due to capillary action, and liquid leakage does not occur.

The spaces on the adjacent liquid rising guide paths are open at least in relation to each other through a gap that does not cause capillarity to the surface of the ion selective layer. Further, the gap above the top of the side wall of the liquid rising guide path may communicate with the outside of the measuring instrument via a space other than the liquid rising guide path. Embodiments in which they are in communication are also included in the present invention.

The horizontal passage 14 is filled with a liquid transporting member 16 (such as a linear band, cotton gauze, or a non-woven fabric having continuous gaps) that has continuous fine gaps that can cause capillary action (herein referred to as porous). Filling the porous member for liquid transfer is particularly advantageous when the reference liquid and test liquid are small amounts.

Three pairs of ion selection electrodes 11a, 11b, 11c are housed in an upper frame 18 made of plastic and are normally in a fixed state. This upper frame body 18 is provided with a liquid application opening 12, which extends across the two single liquid application openings (a reference liquid application opening and a test liquid application opening). the liquid applied to each liquid application opening (
A bridge 19 (for example, a yarn bridge such as a heated polyethylene terephthalate fiber yarn (spun yarn)) is provided for electrically conducting the reference liquid and the test liquid to each other.

Although not shown in the figure, a small protrusion area is provided around the liquid application opening 12 to prevent the liquid supplied at one point from overflowing to the outside of the opening and to easily and reliably apply the liquid. It can be used as a guide.

A sheet-like first intermediate member (spacer) 26 is provided at the lower part of the upper frame 18. A part of the descending passage 13 for the liquid supplied at the zero point and the upper space 25 of the liquid rising guide passage are formed by this first intermediate member (spacer) 26. It is formed in the shape of an opening in the intermediate member 26.

Furthermore, a sheet-like water-impermeable second intermediate member (for example, a plastic mask) is disposed below the first intermediate member 26.
A descending passage 13 for the liquid supplied at the zero point where 20 is provided.
A portion of the liquid ascending guide paths 15a, 15b, and 15c are formed in the shape of an opening in the sheet-like water-impermeable second intermediate member 20. The first intermediate member 26 and the water-impermeable second intermediate member 20 are sequentially attached to the lower surface of the upper frame 18 by adhesive (pressure-sensitive adhesive, heat-sensitive adhesive, etc.), heat fusion, or physical retainer. It is desirable that they be joined.

A lower frame 21 made of plastic is disposed below the water-impermeable sheet-like second intermediate member 20 .

The horizontal passage 14 is formed in the lower frame 21 as a recess. This horizontal passage 14 is filled (accommodated) with a liquid transfer porous member 16 as desired.The liquid transfer porous member 16 may be fixed to the horizontal passage 14.

Ion selection electrodes 11a, 1 are provided on both sides of the lower frame 21.
1b, 11c, each electrical connection area 22a, 22b,
A notch 23 is provided to expose the portion 22c downward (see FIG. 1B). The notches 23 may be formed individually to suit each of the plurality of pairs of ion-selective electrodes, and the electrical connection areas of all the ion-selective electrodes can be formed in a pair of notches provided on both sides of the instrument. An example of the latter is shown in the drawing.

The f-section frame 21 is located on the lower surface of the water-impermeable second intermediate member 20.
It is preferable that they be joined by an adhesive (pressure-sensitive adhesive, heat-sensitive adhesive, etc.), heat fusion, or a physical engagement material.

Note that as long as it is possible to fill the ion selective electrode and, if desired, fill the porous member for liquid transfer, the upper frame,
Of course, all or part of the first intermediate member, the water-impermeable second intermediate member, and the lower frame may be integrally molded. In addition, an upper frame body, a first intermediate member,
There is no particular need to integrate the water-impermeable second intermediate member and the lower frame, and any one of the upper frame, the first intermediate member, the water-impermeable second intermediate member, and the lower frame It can also be constructed from a plurality of members.

The upper frame, the first intermediate member, the water-impermeable second intermediate member, and the lower frame can be manufactured from any desired shape-retentive material, but various properties such as moldability and impact strength are taken into consideration. Then, it is preferable to form it from a plastic material, and for example, a known method such as a method of putting a plastic material into a desired mold and molding it, or a drawing method using a sheet-like plastic material can be used.

That is, as illustrated in FIGS. 1 and 2, a sheet-like ion selective electrode is placed between an L part frame body having an opening at a position corresponding to the opening for each liquid handle, and a position corresponding to the opening. and an opening at a position corresponding to the front opening of the liquid rising guide path, and the latter opening is made larger than the top opening of the liquid rising guide path so as to prevent it from coming into contact with the rising liquid. a water-impermeable second intermediate member having an opening at a position corresponding to the descending passage and the liquid rising guide passage; and a lower frame having a recessed portion forming a horizontal passage. An ion activity measuring instrument equipped with a bridge fixed to the upper frame so as to cross the opening of the upper frame can be particularly effectively used in carrying out the ion activity measuring method of the present invention.

FIG. 3 shows another embodiment of the ion activity measuring instrument of the present invention,
Similar to FIG. 2 above, this is a diagram showing each constituent member separately so as to explain in detail each member constituting the ion activity measuring instrument.

Also in the ion activity measurement device of the embodiment shown in this figure,
Three pairs of sheet-like ion selective electrodes 31a, 31b, and 31c each having an ion selective layer on the top are arranged so that the ion selective layer is on the lower side.

The three pairs of ion selection electrodes 31a, 31b, and 31c are housed in an upper frame 38 made of plastic, and are normally in a fixed state. This upper frame 38 is provided with a liquid application opening 32 .

In the example of FIG. 3, three pairs of ion selection electrodes are distributed into one pair and two pairs on the left and right sides of the liquid application opening 32.

With this configuration, the distance between the liquid application opening 32 and the farthest ion selection electrode is
This is advantageous when using a highly viscous liquid as a sample because it is closer than the measuring instrument shown in the example.

A plastic bridge support member 52 having two openings 51 at positions corresponding to the liquid application openings 32 is placed at the bottom of the upper frame 38 . A bridge 39 is provided across the openings of the two openings 51 to electrically conduct the liquids (reference liquid and test liquid) applied to each part of the liquid application opening. It is equipped.

A sheet-like first intermediate member 46 is provided on the lower side of the bridge support member 52. A descending passage 3 for the liquid supplied at the zero point is provided.
Part of 3, upper spaces 45a and 45 of the liquid rise guide path
b is formed in the first intermediate member 46 in the shape of an opening.

Furthermore, a sheet-like water-impermeable second intermediate member (for example, a plastic mask) 40 is provided below the first intermediate member 46. A part of the descending passage 33 for the liquid supplied at zero point, Liquid rising guide paths 35a, 35b and 35
c is formed in the shape of an opening in this sheet-like water-impermeable second intermediate member 40 . Liquid rising guide path 35a, 3
5b, 35c and their relationships with the upper spaces 45a, 45b are similar to those in the embodiments shown in FIGS. 1 to 1D above. The first intermediate member 46 and the water-impermeable second intermediate member 40 are coated with an adhesive (pressure-sensitive adhesive, heat-sensitive adhesive, etc.) on the lower surfaces of the bridge support member 52 and the upper frame 38.
, heat fusion, or physical engagement material.

A lower frame 41 made of plastic is disposed below the sheet-like water-impermeable second intermediate member 40 .

The horizontal passage 34 is formed in the lower frame 41 as a recess. Then, this horizontal passage 34 is filled with a liquid transfer porous member 36 if desired. Note that the liquid transfer porous member 36 may be fixed to the horizontal passage 34.

Ion selection electrodes 31a, 3 are provided on both sides of the lower frame 41.
A notch 43 is provided to expose the electrical connection area of each of 1b and 31c downward (see FIG. 1B).

The lower frame body 41 is on the lower surface of the water-impermeable second intermediate member 40,
It is preferable that they be joined by an adhesive (pressure-sensitive adhesive, heat-sensitive adhesive, etc.), a heat-fusion blade, or a physical engagement material.

The upper frame, the bridge support member, the first intermediate member, the water-impermeable second intermediate member, and the lower frame as long as they are capable of accommodating the ion-selective electrode and filling the optional liquid transport porous member. Of course, all or part of the body may be formed as a body. Further, as in the above example, each member may be composed of a plurality of members, and each member may be formed of any material. That is, in the ion activity measuring instrument composed of the members shown in FIG. 3, the upper frame 18 shown in FIG. 2 has a different arrangement of the liquid application opening, and
This is an example in which the upper frame body 38 has an opening at a position corresponding to the opening for each liquid handle, and the bridge support member 52 has an opening at a position corresponding to the opening.

The measuring instrument shown in FIG. 3 has an embodiment in which the upper frame body and the bridge support member are divided as described above.

Since each member has a simple shape, it has the advantage of being easy to manufacture.

In addition, in the measuring instrument shown in Fig. 3, the thread bridge is not fixed to the upper frame but is fixed to an independent bridge support plate (bridge support member). No distortion occurs in the upper frame during the mounting operation, and therefore no distortion spreads to the ion selection electrode. Therefore, the assembly accuracy during the manufacture of the instrument is improved, and as a result, there is an advantage that highly accurate ion activity measurement can be easily obtained.

FIG. 4 shows another embodiment of the ion activity measuring instrument of the present invention,
Similar to FIGS. 2 and 3 above, this is a diagram showing each constituent member separately so as to explain each member constituting the ion activity measuring instrument in detail.

In the example shown in FIG. 4, the upper frame 48 and the bridge support member 61 are provided independently, similar to the example shown in FIG.

In the example of FIG. 4, the bridge support member 61 has a large opening 62 and, in addition to its function as a bridge support member, the first intermediate member 26 shown in FIGS. An upper space 62 of the liquid guide path corresponding to the space 25 is provided.

Therefore, as an intermediate member, the opening 5 corresponding to the descending passage
3 and the openings 55a, 55b corresponding to the liquid flow industry inner path,
It has only a water-impermeable intermediate member 50 having a diameter of 55c.

That is, the ion activity measurement device constructed from the respective members shown in FIG. The latter opening is located at a position corresponding to the top surface of the liquid rising guide path and at a position corresponding to the top surface opening of the liquid rising guide path, and the latter opening is arranged to prevent the liquid from coming into contact with the rising liquid. A container comprising a bridge support member having a larger opening, a water-impermeable intermediate member having an opening corresponding to the descending passage and the liquid ascending guide passage, and a lower frame having a recess forming a horizontal passage. FIG. 3 shows an embodiment in which the bridge is fixed to the bridge support member so as to cross the opening of the bridge support member.

Note that, as shown in FIGS. 5A and 5B, a liquid transfer porous member 64 is placed on the liquid rising guide path in each of the embodiments shown in FIGS. 1 to 4. FIG. 5A is a diagram corresponding to FIG. 1D, and
FIG. 5B is a perspective view of the liquid transfer porous member 64.

Although various typical embodiments of the measuring instrument of the present invention shown in the accompanying drawings have been shown so far, it goes without saying that the ion activity measuring instrument of the present invention is not limited to these embodiments. For example, a preferred embodiment of the ion activity measuring instrument of the present invention is an ion activity measuring instrument in which the characteristic configurations shown in each embodiment are mutually combined.

In the measuring instrument of the present invention, the bridge and the liquid transfer member can be appropriately selected from (porous) materials having continuous fine gaps that can cause capillary action. Porous materials for bridges include membrane filters made of heating threads, filter paper, filter paper laminated with a single layer of hydrophobic organic polymer on both sides as described in JP-A-55-20499, and porous materials for liquid transfer members. Line color obi cloth,
In addition to the cotton gauze nonwoven fabric, various types of heatable woven fabrics, heatable knitted fabrics, membrane filters, filter papers, etc. can be used.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an example of the ion activity measuring instrument of the present invention. Figure 1A is a three-dimensional cross-sectional view of the ion activity measuring instrument shown in Figure 1 taken along line I-I, and Figure 1B is a bottom view of the ion activity measuring instrument shown in Figure @1. 1C is an enlarged view of the circled part X of the three-dimensional cross-sectional view shown in FIG. FIG. FIG. 2 is a diagram showing each constituent member separated in order to explain in detail each member constituting the ion activity measuring instrument shown in FIG. 1. FIG. 3 shows another embodiment of the ion activity measuring instrument of the present invention,
Similar to FIG. 2 above, this is a diagram showing each constituent member separated so as to explain each member constituting the ion activity measuring instrument in detail. FIG. 5S4 is a diagram showing still another embodiment of the ion activity measuring instrument of the present invention, with each component separated, similar to FIGS. 2 and 3 above. FIG. 5A is a diagram schematically showing the state of adhesion of liquid to the surface of the ion selective electrode in still another embodiment of the ion activity measuring instrument of the present invention. Figure 5B is 5A of L.
FIG. 2 is a perspective view of a porous liquid transfer member used in the embodiment shown. 11a, llb, 11C: ion selection electrodes 31a, 31
b, 31c: Ion selective electrode 111 Niblast sheet support 112: Metallic silver vapor deposited layer 113: Silver chloride layer 114: Electrolyte layer 115: Ion selective layer 12.32: Liquid application opening 13.33: Liquid Descending passage 14.34: Liquid horizontal passage z 15 a, 15b, 15c: Liquid rising guide passage 25:
Spaces 35a, 35b, 35c of liquid rise guide path 1: liquid rise guide paths 45a, 45
b: Spaces 55a, 55b, 55c on the liquid rising guide path:
Liquid rising guide path 62: Space on liquid rising guide path 16.36: Porous member for liquid transfer -18, 38,
48: Upper frame 19. 39 Ni bridge support member 26. 46: First intermediate member (spacer) 61 Ni bridge support member (spacer) 20. 40: Water impermeable second intermediate member (mask) 50: Water impermeable Transparent intermediate member (mask) 21.41: Lower frame 22a, 22b, 22C: Electrical connection area of ion selective electrode 23.43: Notch 64: Porous member for liquid transfer Patent applicant: Fuji Photo Film Co., Ltd. Agent
Patent Attorney Yasushi Yanagawa Figure 5A Figure 5B

Claims (1)

[Claims] 1. A reference liquid and a test liquid are applied to the surface of each ion-selective layer of at least a pair of sheet-like ion-selective electrodes having an ion-selective layer on the top, which are electrically separated from each other. In a method for measuring the ion activity of a test liquid, which consists of measuring the potential difference between each ion-selective electrode while both liquids are electrically connected to each other by a bridge, each sheet-like ion-selective electrode is The selective layer is placed on the lower side, and each liquid applied from above is moved to a position below the surface of the ion selective layer, and then capillary action occurs on the surface of the ion selective layer. Applying each liquid to the surface of the ion-selective layer by raising each liquid to the surface position of the ion-selective layer through a liquid rising guide path in which the top of the side wall is separated from the surface of the ion-selective layer by a gap that does not interfere with the liquid. A method for measuring ion activity characterized by: 2. A patent claim characterized in that the liquid moved to a position below the surface of the ion-selective layer is moved in a horizontal direction to just below the surface of the ion-selective layer, and then raised to the surface position of the ion-selective layer. The method for measuring ionic activity according to item 1. 3. The method for measuring ion activity according to claim 2, wherein the horizontal movement of the liquid is performed through a porous member for liquid transfer. 4. The ion according to any one of claims 1 to 3, wherein the liquid rises to the surface of the ion selective layer while being guided by a porous member for transporting the liquid. How to measure activity. 5. at least a pair of sheet-like ion selective electrodes electrically separated from each other and having an ion selective layer on the top; a liquid applying section for applying a reference liquid and a test liquid to the surface of each ion selective layer; In an instrument for measuring the ion activity of a test liquid having a bridge for electrically conducting both liquids to each other, each sheet-like ion-selective electrode is arranged with the ion-selective layer facing downward, and the liquid applying part is , an upper liquid application opening, a descending passageway that moves the liquid to a position below the ion-selective layer surface, a horizontal passageway that moves the liquid horizontally just below the ion-selective layer surface, and a liquid then ion-selective layer surface. A liquid rising guide path (however, the top of the side wall of this liquid rising guide path is separated from the surface of the ion selective layer by a gap that does not cause capillary action) to rise to the surface of the layer. An ion activity measuring instrument characterized by comprising: 6. The ion activity measuring instrument according to claim 5, wherein the horizontal passage is filled with a porous member for liquid transfer. 7. The ion activity measuring instrument according to claim 5, characterized in that a porous member for liquid transfer is placed on or in the liquid rising guide path. 8. The ion activity measuring instrument according to claim 6, characterized in that a porous member for liquid transfer is placed on or in the liquid rising guide path. 9. Claims 5 to 9, characterized in that the space above the top of the side wall of the liquid rising guide path communicates with the outside of the measuring instrument via a space other than the liquid rising guide path. The ion activity measuring device according to any of Item 8. 10. Sheet-like ion selective electrodes are arranged in an upper frame body having openings at positions corresponding to the liquid application openings, at positions corresponding to the openings, and at positions corresponding to the upper surface openings of the liquid rising guide path, respectively. a first intermediate member having an opening, the latter opening being larger than the top opening of the liquid ascending guide so as not to come into contact with the rising liquid; a descending passage and a liquid rising guide; a water-impermeable second intermediate member having an opening at a position corresponding to the lower frame, and a lower frame having a recess forming a horizontal passage, the bridge extending across the opening in the upper frame; The ion activity measuring instrument according to any one of claims 5 to 8, wherein the ion activity measuring instrument is fixed to the upper frame body. 11. An upper frame body in which the sheet-like ion selective electrode has an opening at a position corresponding to each liquid application opening, a bridge support member having an opening at a position corresponding to the opening, and a bridge support member corresponding to the opening. The latter opening is larger than the upper opening of the liquid rising guide so as to prevent it from coming into contact with the rising liquid. a water-impermeable second intermediate member having an opening at a position corresponding to the descending passage and the liquid rising guide passage; and a lower frame having a recessed portion forming a horizontal passage. 8. The ionizing device according to any one of claims 5 to 8, characterized in that the bridge is fixed to the support member so as to cross the opening of the bridge support member. Quantity measuring instruments. 12. Sheet-like ion selective electrodes are arranged in an upper frame body having openings at positions corresponding to the respective liquid application openings, at positions corresponding to the openings, and at positions corresponding to the upper surface openings of the liquid ascending guide path. a bridge support member having an opening, the latter opening being larger than the upper opening of the liquid ascending guideway so as not to come into contact with the rising liquid; a water-impermeable intermediate member having an opening at a corresponding location and a lower frame having a recess forming a horizontal passage; The ion activity measuring instrument according to any one of claims 5 to 8, wherein the ion activity measuring instrument is fixed to a member.