JPS58223741A - Electrode structural body - Google Patents

Abstract

PURPOSE:To obtain reliable data, by forming a passage, an ion electrode part and a comparison electrode part on a main body and combining said body with the main body with a packing material in one body. CONSTITUTION:Titled device is provided with a liquid sample passage 4 formed in main bodies 1, 1', an ion sensitive membrane 5 detecting an ion material in the liquid sample which is dispenced at an optional position and forms a part of the passage wall and at least one ion electrode part constituted by the membrane 5 and an electrically conductive body ( I )7 connecting electrically with the membrane 5. Further, at least one comparison electrode part constituted by a membrane for comparison 8 forming a part of the passage wall which is placed in the neighborhood of the position of the membrane 5 and an electrically conductive body (II)9 connecting electrically with the membrane 8, are provided in this structural body.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a flow cell type electrode assembly for measuring ion concentration in a liquid sample.

[Technical background of the invention and its problems]

An analyzer incorporating an ion-selective electrode with an ion-selective membrane is widely used to measure the concentration of ions or the activity of ions in a solution; As can be seen, just by dipping the electrode in the solution #1
The concentration or activity of the desired L ion can be displayed almost instantaneously.

Among these types of analyzers, devices incorporating 70 cells are capable of continuous measurement of a large number of samples, and are used in the fields of clinical chemistry and biochemistry, where the amount of sample liquid is extremely small. It is widely applied in

However, Kotobuki has found that in ion concentration analyzers used in the biochemical field, the stability of the ion-selective electrode built into the test liquid over its lifetime is still insufficient. , compared to ion concentration analyzers used in the physical and chemical fields, the number of specimens processed is far greater.

There are other inconveniences.

Furthermore, since the test liquid in the biochemical field is usually a body fluid such as blood or urine, the inner walls of the liquid delivery piping, the inside of the flow cell, and the membrane surface of the electrode group are heavily contaminated. In such a state, the response of the electrode group becomes slow, resulting in a decrease in sample processing capacity.

For this reason, once a certain amount of sample processing has been completed, the procedures of (1) replacing only the ion-sensitive membrane of the deteriorated electrode with a new one, and (2) replacing the entire electrode with a new one have been carried out.

However, in the method (2), the work of pasting the membrane or fitting the membrane is complicated, and furthermore, the work of refilling the internal electrolyte accompanying the work of replacing the membrane is unavoidable. In order to replace the entire electrode, the internal reference electrode made of silver provided inside the electrode must also be discarded at the same time, resulting in an expensive method. Furthermore, in this method, the work of installing a new electrode in the 70-cell is complicated because care must be taken to ensure the condition of the fasteners and to avoid accidents such as leakage of the sample solution. In addition to the above, ■.

With method (2), it is difficult to completely remove the dirt that has adhered to the inside of the 70-cell, so even if the electrodes and ion-sensitive membrane are replaced, the calibration curve and response speed may be affected by the dirt that remains inside the flow cell. It often had a negative impact on

Furthermore, conventional ion electrodes mainly involve pasting an ion-sensitive membrane on one end of a cylindrical hollow body, filling the interior with electrolyte, and then inserting and fixing an internal reference electrode of steel/silver chloride obtained by electrolysis. Because they are manufactured through a complicated process, it takes a long time to make them.

[Purpose of the invention]

The present invention eliminates the above-mentioned problems, that is, the troublesome work associated with replacing the membrane and replacing the electrode when the ion electrode deteriorates, and also simplifies the electrode manufacturing process. The purpose of the present invention is to provide an ion electrode structure in which the membrane can be easily replaced at any time and reliable data can be obtained.

[Summary of the invention]

The electrode assembly of the present invention is an assembly-structured electrode assembly consisting of a main body of an organic polymer material, and includes a liquid sample passage formed within the main body; and a liquid sample passage formed in the main body; at least one ion electrode portion comprising an ion sensitive membrane that senses ionic species in the liquid sample forming a part thereof and a conductor (I) electrically connected to the ion sensitive membrane; at least one comparison electrode section comprising a comparison membrane installed close to the sensitive membrane and forming a part of the wall surface of the passage, and a conductor (n) electrically connected to the comparison membrane; It is characterized by a structure consisting of.

The electrode structure of the present invention will be explained in detail based on an example cross-sectional view shown in FIG. In the figure, 1.1' is a main body 12 made of an organic polymeric material with a plate-like or block-like shape, and the two are brought into contact with each other via a backing material 2 at a combination surface A, and a fastener 3 to form a liquid-tight integral structure as a whole. Examples of organic polymer materials used include polyvinyl chloride, polycarbonate, and acrylic resin.

Although styrene resin can be used, polyvinyl chloride is preferable from the viewpoint of processability and cost. Moreover, XXXX''1 is preferable as the backing material.

4 is a liquid sample passage having an inlet 4' and an outlet 4N. The passageway is formed, for example, by machining a groove of a predetermined shape on the contact surface of the main body 1 with the main body 1', and combining this with the main body 1'.

The liquid sample flows in through the inlet 4' and exits through the outlet 4'y.

5 is an ion-sensitive membrane that seals the opening on the passage 4 side of the through hole 6 bored from the outer surface of the main body l at an arbitrary predetermined position to the passage 4, and therefore constitutes a part of the wall surface of the passage 4. be. A conductor is provided in the through-hole 6 sealed with the ion-sensitive membrane 5 to electrically connect with the ion-sensitive membrane 5 and to guide electrical signals from the layer to an external measurement system (not shown). (■) 7 is inserted and fixed, and the ion electrode part is constituted as a whole.

The ion-sensitive membrane used is based on polymeric materials such as polyvinyl chloride, polyurethane, silicone rubber, and epoxy resin. (for N&+), nonactin (for NH,+),
Methyltetradedecyl ammonium chloride (CJ-
), etc., in a predetermined amount.

Reference numeral 8 denotes a comparison membrane that seals the opening on the passage 4 side of the through hole 6' formed by the passage 4t from the outer surface of the ion electrode part IK at a position close to it, and thus constitutes a part of the wall surface of the passage 4. It is.

The inside of this through-hole 6' is electrically connected to the comparison membrane 8 in the same way as the ion electrode part.
A conductor (■
) 9 is inserted and fixed, and the reference electrode section is constituted as a whole.

As the comparative membrane 8, nine membranes were used in which the base material used in the production of the ion-sensitive membrane 50 was made to contain powders such as AgC and KC.

As the conductor (I) and (n), Au HP tv
Metals such as Ag, Cu, Nl, alloys thereof, Nesa glass, or various conductive plastics are used, but among these, Cu is preferred because it is easily available and inexpensive.

The ion electrode section and the comparison electrode section are formed as follows. That is, first, the conductor (I) and the conductor (II) are inserted and fixed into the through holes 6 and 6' of the main body 1 to a depth that takes into account the thickness of the six films to be formed, and then the through holes 6 and 6' are fixed. , 6' on the passage 4 side, the above-mentioned ion-sensitive membrane and a membrane agent prepared by dissolving the comparative membrane material in, for example, tetrahydrofuran are injected, and then cured to form a membrane.

In this case, the following embodiments can be adopted regarding the conductors (I) and (II). The first method is to use the metal wire or metal rod 11 as it is (FIG. 2), and the second method is to use a thin metal plate 12 with approximately the same cross section as the through holes 6, 6', as shown in FIG.
A method of attaching the metal wire IIJ13 to the metal wire by welding or soldering and inserting it into the through holes 6 and 6' (in this case,
It is economical because the membrane area can be reduced and the amount of conductor used can be reduced. ), thirdly, as shown in Fig. 4, after inserting and fixing the thin metal wires 14 into the through holes 6, 6', electroless plating, vapor deposition, etc. are applied to the openings on the passage 4 side. Then, a method of forming a metal film 15 in the gap between the thin wire 14 and the through holes 6, 6', or a method of injecting Nesa glass into the gap can be applied.

The electrode structure of the present invention first includes the above-mentioned passage 4 in the main body 1.
, an ion electrode section, and a comparison electrode section are formed, and then combined and integrated with the main body 1' via the backing material 2.

When measuring the ion concentration in a liquid sample, the electrode assembly configured in this manner is configured to include each necessary mechanism, such as a liquid feeding pump that feeds the sample to the passage 4, an ion electrode section, a comparative A potentiometer and an ion concentration calculation display may be connected to each electrode section.

In addition, although the figure illustrated the case where there is one ion electrode part and one comparison electrode part, in the electrode structure of the present invention,
No problem will arise even if a plurality of ion electrode sections and comparison electrode sections are provided as necessary.

[Embodiments of the invention]

A passage 4, an inlet 4', and an outlet 4#, which are grooves 2 cm deep, are machined on the surface of a transparent polyvinyl chloride block, which is a rectangular parallelepiped with a length of 10 m, a width of 25 mg, and a thickness of 10 m. In addition, holes for fasteners 3 and diameter 2 holes are provided at the four corners.
The main body 1 was formed by drilling simple through holes 6 and 6'.

A copper wire with a diameter of 2 mm and a length of 30 tm is inserted into the through holes 6 and 6', and the distance to the opening on the passage 4 side of the through holes 6 and 6' is 300 μm.
I inserted and fixed it so that it would be a city.

Next, a membrane agent for a potassium ion-sensitive membrane was prepared by dissolving 50 parts of polyvinyl chloride, 49 parts of dioctyl adipate, and 1 part of palinomycin in tetrahydrofuran, and 70 parts of polyvinyl chloride and 30 parts of potassium chloride were dissolved in 7 ran of tetrahydrofuran. A membrane agent for comparative membranes was prepared.

These membrane agents were injected into the openings of the through holes 6 and 6' with a syringe to a thickness of 300 μm, thereby forming an ion-sensitive membrane 5 and a comparative membrane 8.

After each layer is sufficiently stabilized, a Teflon sheet with a thickness of 0.05 rm is used as the backing material 2.
The main body 1' made of transparent polyvinyl chloride with a thickness of 3 mm is stacked one on top of the other and tightened with a fastener 3 of M1, 5 bolts and nuts to form the electrode structure of the present invention having the structure as shown in FIG.

In the passage 4 of this electrode structure, there is a concentration IF'M-10-"
When a KC solution of M was poured and the potassium ion concentration was measured, the temperature was 37. OC shows a Nernst response, and its slope is 60.5 mV/d e c ad
e.

Good characteristics were obtained with a 95-chip response time of less than 5 seconds.

・” [Effects] As clearly shown in the above explanation, the electrode structure of the present invention eliminates the need to manufacture and process the flow cell and ion electrode bodies separately and combine them as in the past. , - It can be manufactured through a consistent process, reducing the processing cost.Also, even if the electrode characteristics deteriorate and need to be replaced, for example, it does not have the conventional internal reference electrode made of silver, but instead is made of a conductor made of an inexpensive material. Therefore, even if the feather cost and the above-mentioned processing cost are combined, the cost is greatly reduced compared to the conventional method, and it is effective in making it durable for disposable use.Furthermore, when the electrode deteriorates, there is no need to replace the conventional membrane or reuse the electrolyte. It is possible to avoid the complicated work of filling, and also avoid the work of removing dirt inside the conventional 70-cell, so it is useful and has the effect of greatly reducing maintenance for the user.In addition, it is easy to process. It also has the effect of making it possible to use multiple electrodes.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of the electrode structure of the present invention, and shows the positional relationship of each component. 2nd~
Figure 4 shows the conductor (I) of the electrode structure in Figure 1, respectively;
This is a book that shows the aspect of (II).

Claims (1)

[Claims] An assembled electrode assembly consisting of a main body of an organic polymeric material, comprising: a liquid sample passage formed within the core body; a part of the wall surface of the passage installed at any location of the passage; at least one ion electrode portion comprising an ion-sensitive membrane that senses ionic species in the liquid sample forming a liquid sample; and a conductor (I) electrically connected to the ion-sensitive membrane; at least one comparative electrical conductor (n) that is installed close to the position of the comparative film and forms a part of the wall surface of the passage, and a conductor (n) that is electrically connected to the comparative film; An electrode structure characterized by having a structure consisting of.