JPS61102550A - Instrument for measuring ionic activity - Google Patents

Abstract

PURPOSE:To obtain a measuring instrument which can be easily produced and can measure always exactly ionic activity by adhering the end edge of the ion selective electrode layer of an ion selecting electrode pair to the upper part of a supporting plate. CONSTITUTION:The measuring instrument is constituted of the ion selecting electrode pair 20 consisting of a pair of ion selecting electrodes 21, 22 disposed on the supporting plate 10 and a porous bridge 50 which conducts electrically the sample liquid and reference liquid spotted respectively to both electrodes 21, 22. The end edge of at least the ion selective electrode layer of the electrode pair 20 is adhered by an adhesive agent 30 to the upper part of the plate 10. The reference electrode and sample electrode arrive respectively at the electrodes 21 and 22 when the reference electrode having the known activity of ions and the sample liquid having the unknown activity are respectively spotted to spotting holes 41 and 42. On the other hand, the boundary faces of both liquids contact with each other to establish the electrical conduction therebetween the therefore the potential difference corresponding to the difference of the ionic activity between the reference liquid and the sample liquid is generated near the center of the bridge 50. The ionic activity in the sample liquid is calculated if the potential difference is measured.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to aqueous liquid samples, such as alcoholic beverages and beverages.

Water flow, especially biological fluids (blood, urine, ll1lil fluid, etc.)
Botensiome the busyness (or concentration) of a specific ion inside]
This invention relates to an ion activity measuring instrument for constant φ analysis at the edge.

(Prior art) A slide-type activity measuring instrument capable of spotting a liquid sample and measuring the concentration of specific ions contained therein is disclosed in No. 1988-211648, etc. Disclosed.

Generally, in such ion activity measuring instruments, an ion selective layer that selectively responds to specific ions is provided as the outermost layer.
At least one pair of ion-selective electrodes
No. 156848, etc.) is placed on a support plate, and one electrode on each electrode of the ion-selective electrode pair is placed on the support plate.
An upper lid is provided with a pair of spotting holes, and electrical continuity between the sample liquid dispensed to one spot of the spotting hole pair and the reference solution dispensed to the other of the spotting hole pair is provided. A porous bridge (such as strands of fibers) that achieves (liquid junction) is provided on the top lid.

Conventionally, when fixing an ion-selective electrode pair on a support plate, at least a contact layer is provided between the ion-selective electrode pair and the upper cover, as shown in Japanese Patent Laid-Open No. 58-211648. The ion-selective electrode pair is fixed to the upper cover using one water-impermeable member (at least one of which has an adhesive layer on both sides), and then the upper cover is fixed integrally with the support plate. Ta.

However, when trying to attach double-sided tape, etc. to the top surface of the ion-selective electrode pair placed on the support plate, the ion-selective electrode pair is pulled away from the support plate due to the effects of electrostatic attraction, mechanical vibration, wind, etc. Extreme care must be taken as it often lifts up and shifts from its correct position. Therefore, it has been difficult to easily manufacture an ion activity measuring device in which an ion-selective electrode pair is fixed on a support plate using such means.

Also, by such means, Japanese Patent Application Laid-Open No. 58-15684
When an ion-selective electrode pair as shown in No. 8 is fixed on a support plate, the side surface and support in the direction in which the two ion-selective electrodes of the ion-selective electrode pair are lined up (hereinafter referred to as the "longitudinal direction") If a gap is created between the body plate and the sample liquid or reference liquid may penetrate into this gap during measurement of ion activity M, the edge of the ion selective electrode layer having a multilayer structure existing on the side surface During this time, a short circuit occurs due to the sample liquid or reference liquid, and as a result, accurate measurement of ion activity becomes difficult.

(Purpose of 5.) This application is easy to manufacture in view of the problems of the above-mentioned conventional technology.
It is an object of the present invention to provide an ion activity ffi measurement instrument that enables accurate measurement of ion activity at all times.

(Structure of the Invention) The ion activity M measuring instrument according to the present invention is characterized in that at least the fraction of the ion selective electrode layer of the selective electrode pair is adhered to the upper part of the support plate.

Preferably, a partition is provided on the support plate so as to accurately position the ion-selective electrode pair, and an edge of the ion-selective electrode layer of the ion-selective ffl pole pair is adhered to the wall of the partition. .

As a means for bonding the ion-selective electrode pair onto the support plate, a hot-melt adhesive is preferable, and paraffin is particularly preferable because it has excellent electrical insulation and does not have an adverse effect on the electrode constituent materials. However, it is also possible to adhere the ion-selective electrode pair onto the support plate without using these adhesives. For example, the support plate may be formed from a thermoplastic material and heat-sealed to the side surface of the ion-selective electrode pair where the edge of the ion-selective electrode layer is present. Alternatively, a solution prepared by dissolving an ion-selective membrane material having the same function as the outermost layer of the ion-selective electrode layer in an appropriate solvent is applied to the required side surfaces, h, and a portion of the support plate of the ion-selective electrode pair. The membrane may be applied so that they are in contact with each other, and after the solvent has evaporated, the side surface is covered with an ion selective membrane and at the same time it is adhered onto the support.

11 if a partition is provided on the top surface of the support plate.
Cut section and ion selection゛? ! Tripolar pair ion selection type 1! i
? This is achieved by filling the gap remaining between the edges of the J with a hot melt adhesive, a solution of an ion-selective substance, or the like.

The adhesive means described above is used to bond at least the entire edge of the ion-selective electrode layer onto the support plate. ! ! However, other parts of the ion-selective electrode pair (for example, a part consisting only of a metal layer) as long as it does not interfere with ion activity m measurement.
It can also be coated with. That is, as long as a region where the sample solution and reference solution can be dotted, and a region where conductive contact with the terminal of the potential measuring means remains, - the surface of the ion-selective electrode pair is not covered with the adhesive means. It's okay.

and its main effects will be explained.

FIG. 1 is an exploded perspective view of a device for measuring active mass according to the first embodiment/II aspect of the present invention, and FIG. 2 is a perspective view of the device before disassembly. The ion activity measuring instrument shown in these drawings includes a support plate 10 having a pair of partitions 11. An ion-selective electrode pair 20 consisting of the same specific ion-selective electrodes 21 and 22, each of whose electrophoretic layers are insulated from each other by a scratch groove or cut groove. An adhesive 30 for bonding the "longitudinal" side surface area of the ion-selective electrode pair, that is, the side surface area where the edge of the ion-selective electrode layer is present, to the opposing wall surface of the partition section 11.
An upper lid 40 provided with one-point attachment holes 41 and 42 and protrusions 43 and 44 forming porous bridge fusion parts. and a porous bridge (preferred specific example: polyethylene terephthalate fiber ms twisted yarn bridge) 50. The porous bridge 50 is fixed onto the top cover 50 by softening or melting the projections 43 and 44, as shown in Japanese Patent Application No. 59-117348. In addition, ion selective electrode pair 20
The support plate 10 and the top cover 40 to which the They are adhered to each other via adhesive means, but these means are not shown.

In order to adhere the ion-selective electrode pair 20 onto the support plate 10, the electrode pair 20 is placed in the groove between the partitions 11, and between the wall surface of the partition 11 and the side surface of the electrode pair 20 in the "longitudinal direction". After pouring enough bacterial adhesive 30 into the gap to fill the gap, the adhesive 30 is allowed to solidify. When using a hot melt adhesive as the adhesive 30,
Assimilation is achieved by pouring the adhesive in hot liquid form and allowing it to cool to room temperature. Note that in FIG. 1, due to the drawing structure, the adhesive 30 is provided on the wall surface of the partition portion 11 of the support 10, and the ion selective electrode pair 20 is shown separated from the adhesive 30. As is clear from
This drawing does not show one stage of the ion activity measuring device manufacturing process.

FIG. 3A shows the support plate 10, the ion selection electrode pair 20, and the adhesive 3 of the ion activity measuring instrument shown in FIGS. 1 and 2.
FIG. 2 is a sectional view showing the relationship with 0; As shown in this drawing, the distance between the pair of partitions 11 is the "
It is slightly wider than the width between the side surfaces in the longitudinal direction, and the height of the wall surface of the partition section 11 is approximately equal to the height of the ion selection electrode pair 20. The gap between the "longitudinal" side surface of the ion-selective electrode pair 20 and the wall surface of the partition section 11 is filled with an adhesive 30, and the "longitudinal" side surface of the ion-selective electrode pair 20 is filled with the adhesive 30. 30.

FIGS. 3B and 3C are cross-sectional views showing the relationships among the members in a partially modified example of the embodiment (equivalent members are given the same reference numerals as in the embodiment).

In the modification shown in FIG. 3B, the distance between the opposing wall surfaces of the pair of partitions 11 is the width between the sides of the ion-selective electrode pair 20 in the "longitudinal direction" at the bottom surface of the wall surfaces, that is, the width of the ion-selective electrode layer. The width is approximately equal to the width between the opposing edges, and this interval becomes wider toward the top of the wall surface. With this configuration, it is possible to accurately position the ion selection electrode pair 20. Moreover, the volume of the V-shaped groove formed between the "longitudinal" side surface of the ion-selective electrode pair 20 and the wall surface of the partition part 11 is approximately constant, and therefore the depth of the adhesive 30 is also approximately constant. Lateral burial is achieved more reliably.

In the modified example shown in FIG. 3C, the height of the wall surface of the partition portion 11 is slightly higher than the height of the ion-selective electrode pair 20, and the adhesive 30 is applied only to the entire side surface area of the ion-selective electrode pair 20 in the "longitudinal direction". It also covers part of its surface.

Such a configuration is for ion selection (water pair 20 is connected to support plate 1).
Although it is preferable for more secure adhesion on 0,
On the surface, it is necessary to prevent the adhesive 30 from covering the contact area between the sample liquid and reference liquid and the potential measuring means.

Next, the operation of the ion activity measuring instrument according to this embodiment will be explained.

When a reference liquid with a known activity (or concentration) of a specific ion is spotted in the spotting hole 41 and a sample liquid with an unknown activity of the ion is spotted in the spotting hole 42, the reference liquid The sample liquid reaches one ion selection electrode 21 of the ion selection electrode pair 20 that generates a potential corresponding to the activity of the ion, and the sample liquid reaches the other ion selection +Itl 122. On the other hand, the interface between the two liquids comes into contact (liquid junction) near the center of the porous bridge 50, establishing electrical continuity. As a result, a potential difference corresponding to the difference in ion activity between the sample liquid and the reference liquid is generated between the ion selection electrodes 21 and 22, so if this potential difference is measured, the measured value and the difference between the reference liquid and the sample liquid are measured. The ion activity in the sample solution can be determined using a calibration curve (the principle is based on Nernst's equation) determined in advance from the ion activity (2).

FIG. 4 is a perspective view showing a multi-item measurement type ion activity measuring instrument capable of measuring three different types of ions according to another embodiment of the present invention.

The ion activity measurement device shown in this drawing has a pair of spotting holes 410.
and 420 and two pairs of air 1 holes 461 and 471.
462 and 412 and recessed regions 451 , 452 and 455 , a pair of outer frame partitions 110 and a pair of central partitions 111 . and three types of ion-selective electrode pairs 201, 202, and 203 (
For example, a support plate 1 to which xaO, KO, and ciO are adhered (selectively corresponding to xaO, KO, and ciO, respectively) with an adhesive 300
00. Both ends of a porous bridge (strand bridge) 500 are fused to the fused portions 480 and 490 of the recessed areas 451 and 452.

The members other than the support plate 100 and the upper M400 are constructed in the same manner as the ion activity measuring instrument described in JP-A-58-211648.

FIG. 5 shows the support plate 100 and ion selection electrode pairs 201, 202, and 2 of the ion activity measuring instrument shown in FIG.
3 is a cross-sectional view showing the relationship between 03 and adhesive 300. FIG.

In this embodiment, the outer frame partition 110 and the medium heat t
The T-cut portion 111 serves as the ion-selective electrode pair 201 , 202
and 203, both have a structure similar to the cut section shown in FIG. 3B described above, and the cross section of the central partition section 111 is approximately an isosceles triangle. It is preferable to securely fix each ion selection electrode pair horizontally or each ion selection electrode pair on the support plate using the configuration shown in FIG. 3A or 3C described above. It is also possible to adhere to jij.

In the ion activity measuring instrument shown in this embodiment, one sample solution and one reference solution are poured into the spotting holes 410 and 420, respectively.
By the action of a liquid distribution member (not shown), both liquids are distributed to each ion-selective electrode pair by simply applying the liquid to each ion-selective electrode pair. The corresponding three types of ion activities, for example, Na
O, KO, C reaction e) can be measured.

Note that the present invention is not limited to these actual IM embodiments, but can be applied to a multi-item measurement type ion activity measuring instrument having a plurality of porous bridges as described in Japanese Patent Application No. 59-117347. It is also applicable.

(Effects of the Invention) In the ion activity measurement device according to the present invention, at least the edge of the ion selective electrode layer of the ion selective electrode pair is adhered to the support plate and covered with an adhesive or the like. It can be reliably fixed in a precise position and there is no risk of liquid junctions occurring at the edges of the ion-selective electrode layer. Therefore, the ion activity measuring instrument made by Wooden Science makes it possible to measure the ion activity with high accuracy. Furthermore, the single ion activity ff) measuring device of the present invention can be manufactured more easily than similar conventional devices.

[Brief explanation of drawings]

Fig. 1 is a perspective exploded view showing an ion activity measuring instrument which is a partial embodiment of the present invention, Fig. 2 is a perspective view not showing its shape before disassembly, and Fig. 3∆ is a partially enlarged view. FIG. 2 is a sectional view taken along the line 3-3; FIGS. 3B and 3C are sectional views similar to FIG. 3A showing a partial modification thereof; and FIG. 4 is another part of the present invention. ! ! FIG. 5 is a sectional view taken along the line 5-5 in FIG. 4 showing an enlarged part of the device. 10.100...Support plate 11...Partition part 110...Outer frame partition part 111...Central partition part 20.201.202,203...Ion selection electrode pair 21.22... Ion selective electrode 30.300...Adhesive 40,400...
Top lid 41.410,42,420... points arrived
Hole 50.500...Porous bridge (twisted bridge) 1st

Claims (1)

[Scope of Claims] 1) At least one pair of ion-selective electrodes arranged on a support plate, and a sample liquid spotted on one electrode of the pair of ion-selective electrodes and a sample solution spotted on the other electrode of the pair of ion-selective electrodes. In the ion activity measurement device having a porous bridge that electrically conducts with the reference liquid, an edge of at least the ion-selective electrode layer of the ion-selective electrode pair is adhered to and covered with the upper part of the support plate. An ion activity measuring instrument characterized by: 2) At least a pair of partitions are provided on the support plate, and the edges of the ion-selective electrode layer are adhered to and covered with the walls of the partitions. The ion activity measuring device according to item 1. 3) The distance between the opposing wall surfaces of the at least one pair of partitions is approximately equal to the width between the opposing edges of the ion selective electrode layer of the ion selective electrode pair at the lower part of the wall surface, and the distance between the opposing edges at the upper part The ion activity measuring instrument according to claim 2, wherein the ion activity measuring instrument is wider than the width. 4) According to any one of claims 1 to 3, the edge of the ion-selective electrode layer is bonded to the upper part of the support plate with a hot-melt adhesive. The ion activity measurement device described. 5) The ion activity measuring instrument according to claim 4, wherein the hot-melt adhesive is paraffin.