JPH0476428B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention is applicable to aqueous liquid samples such as alcoholic beverages, beverages,
An ion activity measurement device for quantitatively analyzing the activity (or concentration) of specific ions in tap water, especially biological fluids (blood, urine, saliva, etc.) by potentiometry, and an ion activity measurement method using the same It is related to.

(Prior art) Slide-type ion activity measuring instruments that can spot a liquid sample and measure the activity of specific ions contained therein are disclosed in JP-A-58-211648 and JP-A-59. -30055, Japanese Patent Application No. 59-11744, etc.

Among these, the ion activity measurement device described in Japanese Patent Application Laid-Open No. 58-211648 and Japanese Patent Application No. 59-11744 has multiple sets of ion activity measuring devices having an ion selective layer in the outermost layer that selectively responds to specific ions. Selection electrode pairs are provided, the lower parts of these ion selection electrode pairs are fixed to the lower support frame, and the upper part has at least one liquid supply hole penetrating through the ion selection electrode pairs at a position corresponding to each of the ion selection electrode pairs. Each ion selective layer is covered with a water-impermeable material layer having a material for supplying liquid so that the shape and area of the liquid contact area are constant, and a cotton bandage is placed on the water-impermeable material layer. A pair of porous liquid distribution members made of cloth, polyester mesh, or the like communicate each pair of liquid supply holes provided at a position corresponding to each one of the plurality of ion selection electrode pairs. The pair of porous liquid distribution members are arranged such that the upper frame has a pair of liquid spotting holes and at least a pair of air vent holes respectively penetrating the pair of porous liquid distribution members, and aligns the lower support frame. Provided on the liquid distribution member. In addition, these ion activity measurement instruments have a method for achieving electrical continuity (liquid path) between the sample liquid that is spotted into one of the pair of liquid spotting holes and the reference liquid that is spotted and supplied to the other of the pair of liquid spotting holes. A porous bridge (strand of fibers) is usually provided on the upper frame.

In the ion activity measuring instrument configured in this way, for example, if the plurality of ion-selective electrode pairs respond to Na, K, and Cl, for example,
When a reference solution with known activities of these ions is spotted on one of a pair of liquid spotting holes and a sample solution with unknown activities of said ions is spotted on the other, both solutions become porous liquids. It penetrates the distribution member and reaches the corresponding ion-selective electrode via the liquid supply hole. On the other hand, the interfaces of both liquids come into contact (liquid junction) near the center of the porous bridge, establishing electrical continuity. As a result,
A potential difference corresponding to the difference in the activity of each ion between the sample solution and the reference solution is generated between the electrodes of each ion-selective electrode pair, so if this potential difference is measured, the measured value and the ion activity of the reference solution can be calculated. Using a calibration curve determined in advance (the principle is based on Nernst's equation), the activities of Na, K, and Cl ions in the sample solution can be determined at the same time.
Can be measured sequentially or at any time.

As mentioned above, this type of ion activity measurement device can measure multiple ion activities by simply applying a small amount of the sample solution and reference solution once, so it is useful for the analysis of aqueous liquid samples, especially blood, etc. It is extremely useful in clinical analysis of samples taken from the human body.

However, when whole blood is dripped and supplied as a sample liquid to such an ion activity measurement device, hemolysis occurs within the porous liquid distribution member, making accurate measurement of ion activity sometimes impossible. Furthermore, providing such a porous liquid distribution member in an ion activity measuring instrument complicates the manufacturing process thereof.

(Object of the Invention) In view of the above-mentioned problems, the present invention has been devised to provide a multi-item product that does not cause hemolysis even when whole blood is used as a sample solution, and can be manufactured more easily than conventional products. The object of the present invention is to provide an ion activity measuring instrument for measurement and an efficient method for measuring ion activity using the same.

(Structure of the Invention) In the ion activity measuring device according to the present invention, at least one of the pair of liquid spotting holes provided in the upper frame is provided at a position corresponding to the liquid supply hole of the water-impermeable member. The present invention is characterized by comprising a liquid supply through hole and a connecting portion that connects these liquid supply through holes to each other so that liquid can be distributed to each of a plurality of ion selection electrode pairs.

In addition, the first method of the ion activity measurement method according to the present invention uses this ion activity measurement instrument,
By relatively moving the dot supply means and this ion activity measuring device at least when dot supplying the sample liquid, the dot supply of the liquid and the ion selection electrode are carried out through the through-hole for liquid supply and the connection part. It is characterized in that distribution and supply are performed substantially simultaneously.

Furthermore, a second method of the ion activity measuring method according to the present invention uses this ion activity measuring instrument, and at least when a sample liquid is dripped, one of the liquid supply through holes is connected to the other. By tilting this ion activity measurement device so that it is located above the liquid supply through-holes and dot-feeding the liquid to the liquid supply through-holes located at the uppermost position, these liquid supply through-holes are Further, the method is characterized in that the spotting supply of the liquid and the distributed supply of the liquid to the ion-selective electrode are performed substantially simultaneously through the connecting portion.

The liquid supply through-holes in the ion activity measurement device of the present invention may have a somewhat larger diameter than the liquid supply holes provided in the water-impermeable member. This is preferable in terms of supplying the required amount of liquid.

The connecting portion is capable of communicating the liquid supply through-holes by means of liquid. Therefore, it is sufficient that the diameter of the connecting portion is such that a capillary phenomenon occurs, but it is also possible to have a diameter that is approximately the same as that of the liquid supply through hole. Further, the connecting portion does not necessarily need to penetrate the upper frame. The non-penetrating connecting portion can also have a larger diameter than the liquid supplying through hole.

(Effects of the Invention) In the ion activity measurement device of the present invention, at least one of the pair of liquid spotting holes is a through-hole for liquid supply provided at a position corresponding to the liquid supply hole of the water-impermeable member. and a connecting portion that connects these liquid supply through holes, making it possible to distribute liquid to each ion selection electrode without providing a porous liquid distribution member under the liquid supply holes. Therefore,
Even when whole blood is used as the sample liquid, the ionic activity of the sample liquid can be measured without causing hemolysis by dotting the sample liquid into the liquid spotting hole. Also,
Since the ion activity measuring device of the present invention does not include a porous liquid distribution member, its manufacture is simpler than that of conventional devices.

The ion activity measuring method according to the present invention uses the ion activity measuring instrument having the structure described above, and involves relatively moving the liquid spotting means (for example, a micropipette) and the ion activity measuring instrument, or tilting the latter. The ion activity can be measured without using a porous liquid distribution member by simultaneously performing spot supply of liquid and distributed supply to each ion selection electrode pair through the liquid supply through hole and the connecting part. This is an excellent method for measuring ion activity in whole blood.

(Embodiments) Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is an exploded perspective view of an ion activity measuring instrument that is an embodiment of the present invention, and FIG. 2 is a perspective view of the instrument after assembly. The ion activity measurement device shown in these drawings includes a lower support frame 100; three types of ion selection electrode pairs 201 (same ion selection electrodes 211 and 2);
21), 202 (consisting of 212 and 222)
203 (consisting of 213 and 223); liquid supply holes 311, 312, 313, 321, 322, 3 penetrating each of the ion selection electrodes;
23; an upper frame 400; and a porous bridge (preferred specific example: a twisted thread bridge made of polyethylene terephthalate fiber) 500.
A pair of liquid spotting holes 410 and 4 are provided in the upper frame 400.
20; recessed portions 451, 452, 455; and ion selection electrodes 211, 212, 213, 221,
Measurement probe insertion ports 461, 462, 463, 471, 47 penetrating through 222, 223, respectively
2,473 are provided. In addition, the recessed portion 45
1 and 452, both ends of the porous bridge 500 are fixed.

The liquid spotting hole 410 is the liquid supply hole 311, 312, 3
It consists of liquid supply through holes 411, 412, 413 provided at positions corresponding to 13, respectively, and connecting parts 414, 415 that connect these liquid supply through holes, and similarly, the liquid spotting hole 420 is a liquid supply hole. 321,
Liquid supply through holes 421, 422, 423 provided at positions corresponding to 322, 323, respectively, and connecting portions 424, 4 that connect these liquid supply through holes.
It consists of 25.

Figures 3A to 3C show the spot supply of a sample liquid and each ion selective layer of each ion selective electrode pair in the first method of the ion activity measuring method of the present invention using the above ion activity measuring instrument. This figure shows the operation for distributing and supplying.

In this method, first, as shown in FIG. 3A, a sample liquid 700 is dotted and supplied from the tip of a spotting supply means (e.g., a micropipette) 600 to the liquid supplying through hole 423 of the liquid spotting hole 420. Continue spot supply while moving the spot supply means in the direction of the arrow (or move the ion activity measurement device in the opposite direction), and as shown in Figures 3B and 3C, the sample liquid is transferred to the connecting portion 425 and It is continuously distributed to the supply through hole 422, the connecting portion 424, and the liquid spot attachment through hole 421. The speed of relative movement between the dot supply means and the ion activity measuring instrument at this time is determined empirically based on the viscosity of the sample liquid and the like. Further, as long as the liquid is supplied so as to communicate with each of the large diameter portions and the small diameter portions, the spot supply may be performed intermittently. Further, the direction of the relative movement does not need to be constant, and may be a reciprocating movement.

Similarly, the reference liquid is also applied to the other liquid spotting hole 410.
Can be supplied on a spot basis. At this time, it is also possible to supply the reference liquid at the same time as the sample liquid by arranging the tip of the spot supply means for the reference liquid parallel to the tip of the spot supply means for the sample liquid and moving them in conjunction with each other. be. However, by providing a porous liquid distribution member below the liquid spotting hole for the reference liquid, the spotting supply of the reference liquid may be performed without the above-mentioned relative movement.

FIG. 4 shows the spot supply of a sample liquid and the distributed supply to each ion selective layer of an ion selective electrode pair in the second method of measuring ion activity of the present invention using a similar ion activity measuring device. It shows the operations to be performed.

In this method, the ion activity measuring device is tilted so that the liquid supply through-hole 423 of the liquid spotting hole 420 is located above the liquid supplying through-holes 421 and 422, and the spotting supply means 600 is The sample liquid 700 is dot-supplied from the tip to the liquid supply through-hole 423, and is continuously supplied to the connecting part 425, liquid supply through-hole 422, connecting part 424, and liquid supply through-hole 421 by the action of gravity. distribute. The inclination angle θ between the ion activity measuring instrument and the horizontal plane at this time is determined empirically based on the viscosity of the sample liquid and the like. Further, the reference liquid can also be supplied to the liquid spotting hole 410 at the same time as the sample liquid, as in the first method described above, or by using other means.

In either of these two methods, the result is that the reference liquid is distributed in the liquid receiving holes 311, 312, 313 and the sample liquid is distributed in the liquid supply holes 321, 322, 323, while both liquids are distributed in the porous bridge 500. diffuse through the interior and surface of the two and come into contact with each other near the center, forming a liquid junction. Therefore, for example, the ion selective electrode pairs 201, 202, 203 each have Na
, K and Cl, then
Between the ion selective electrodes 211 and 221,
Na, K, between the reference solution and the sample solution between 2 and 222, and between 213 and 223, respectively.
Since a potential difference occurs corresponding to the difference in each ion activity of Cl, the measurement probe insertion ports 561 and 56
2,563, 571, 572, 573 and contact each electrode, and measure the potential difference, the ion activity in the sample liquid can be determined as in the conventional multi-item ion activity measuring instrument. Quantity can be measured.

FIG. 5A is a plan view showing the shape of the liquid spotting hole 410 in the ion activity measuring device, and FIGS. FIG.

The liquid spotting hole 410B shown in FIG.
The liquid supply through hole 41 is provided outside of 14B and 415B.
It has a non-penetrating concave connecting portion 416B inscribed in 1B to 413B.

A liquid spotting hole 410C shown in FIG. 5C is provided with a non-penetrating concave connecting portion 416C having a larger diameter than the concave connecting portion 416B.

The liquid spotting holes 410D-F shown in FIGS. 5D-F have non-penetrating concave connecting portions 416D-F and do not have penetrating connecting portions. The diameter of the connecting portion 416D shown in FIG.
The connecting portion 41 shown in FIG. 5E is narrower than the diameter of E.
The diameter of the connecting portion 4 shown in FIG.
The diameter of 16F is wider than the diameter of liquid supply through holes 411F to 413F.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing an ion activity measuring device which is an embodiment of the present invention, FIG. 2 is a perspective view showing the assembled state, and FIGS. 3A to 3C are views showing the ion activity measuring device described above. An explanatory diagram showing the operations for spotting and dispensing the sample liquid in the first method of the ion activity measurement method of the present invention to be used, and FIG. 5A is a plan view showing the shape of the liquid spot hole of the ion activity measuring instrument, and 5B to 5F are explanatory diagrams showing the operations for performing the ion activity measurement device. It is a top view which shows the shape of the liquid spot hole in the example of a partial change of a measuring instrument. 100... lower support frame, 201, 202, 20
3...Ion selective electrode pair, 211, 212, 21
3... One ion selection electrode, 221, 222,
223...Other ion selective electrode, 300...Water impermeable member layer, 311, 312, 313...One liquid supply hole, 321,322,323...Other liquid supply hole, 400...Upper frame ,410,420...
...liquid spot hole, 411, 412, 413, 421,
422, 423, 411B-F, 412B-F,
413B-F...through hole for liquid supply, 414, 41
4B, 414C, 415, 415B, 415C,
416B-F, 424, 425...Connection part, 45
1,452,455...concavity, 461,46
2,463...One measurement probe insertion port, 4
71,472,473...Other measurement probe insertion port, 500...Porous bridge (twisted thread bridge), 600... Spot supply means, 700... Sample liquid.

Claims (1)

[Claims] 1. (a) a lower support frame, (b) a plurality of ion-selective electrode pairs disposed on the lower support frame, and (c) an ion-selective electrode disposed on the plurality of ion-selective electrode pairs. (d) a water-impermeable member having one liquid supply hole at a position corresponding to each of the water-impermeable members; (e) an upper frame having a pair of liquid spotting holes penetrating through the liquid spotting holes; (e) a porous hole through which the reference liquid spotted on one of the liquid spotting holes and the sample liquid spotted on the other are brought into contact and electrically conductive; In the ion activity measuring instrument comprising a liquid bridge, at least one of the liquid spotting holes connects the liquid supply through holes provided at positions corresponding to the liquid supply holes to each other. An ion activity measuring instrument comprising: a connecting portion that can be connected to distribute liquid to each of the plurality of ion-selective electrode pairs. 2. (a) a lower support frame, (b) a plurality of ion-selective electrode pairs disposed on the support frame, and (c) a position corresponding to each of the ion-selective electrodes on the plurality of ion-selective electrode pairs. (d) a pair of liquids placed on the water-impermeable member and penetrating the water-impermeable member at positions that coincide with the liquid supply holes; an upper frame having a spotting hole; (e) a porous bridge that electrically conducts through contact with the reference liquid spotted on one of the liquid spotting holes and the sample liquid spotted on the other side; , at least one of the liquid spotting holes is connected to a liquid supply through hole provided at a position corresponding to the liquid receiving hole, and these liquid supply through holes are connected to each other to form each of the plurality of ion selection electrode pairs. A reference solution whose ionic activity of a specific ion is known is dispensed into one liquid spot hole of an ion activity measurement device consisting of a connecting part that can distribute the liquid to the other liquid spot, and A sample liquid whose ionic activity of the ions is unknown is dot-supplied to the deposition hole, and the dot-supplied reference liquid and sample liquid are respectively passed through the liquid supply hole to one of the plurality of pairs of ion-selective electrodes and The reference liquid and the sample liquid are brought into contact with each other in the porous bridge to form a liquid junction, and a probe is contacted with each of the electrical connection terminal portions of the plurality of pairs of ion-selective electrodes to form a liquid junction between the two electrodes. In an ion activity measuring method comprising measuring a potential difference and calculating the ionic activity of a specific ion in the sample liquid from the measured potential difference, at least a spot supplying means and a By relatively moving the ion activity measuring device, it is possible to substantially spot-feed the liquid through the liquid supply through-hole and the connecting portion and distribute the liquid to the ion-selective electrode pair through the liquid supply hole. A method for measuring ion activity characterized by simultaneously carrying out. 3. (a) a lower support frame, (b) a plurality of ion-selective electrode pairs disposed on the support frame, and (c) a position corresponding to each of the ion-selective electrodes on the plurality of ion-selective electrode pairs. (d) a pair of liquids placed on the water-impermeable member and penetrating the water-impermeable member at positions that coincide with the liquid supply holes; an upper frame having a spotting hole; (e) a porous bridge that electrically conducts through contact with the reference liquid spotted on one of the liquid spotting holes and the sample liquid spotted on the other side; , at least one of the liquid spotting holes is connected to a liquid supply through hole provided at a position corresponding to the liquid supply hole, respectively, and these liquid supply through holes are connected to each other to form each of the plurality of ion selection electrode pairs. A reference solution whose ionic activity of a specific ion is known is dispensed into one liquid spot hole of an ion activity measurement device consisting of a connecting part that can distribute the liquid to the other liquid spot, and A sample liquid whose ionic activity of the ions is unknown is dot-supplied to the deposition hole, and the dot-supplied reference liquid and sample liquid are respectively passed through the liquid supply hole to one of the plurality of pairs of ion-selective electrodes and The reference liquid and the sample liquid are brought into contact with each other in the porous bridge to form a liquid junction, and a probe is contacted with each of the electrical connection terminal portions of the plurality of pairs of ion-selective electrodes to form a liquid junction between the two electrodes. In an ion activity measuring method comprising measuring a potential difference and calculating the ionic activity of a specific ion in the sample liquid from the measured potential difference, the ion activity measurement method is performed at least when the sample liquid is spot-supplied. Tilt the device so that one liquid supply through hole in one of the spotting holes is located above the other liquid supply through holes, and apply the liquid to the liquid supply through hole located at the uppermost position. By depositing and supplying the ion, the liquid is spotted and supplied through these liquid supply through-holes and the connecting portion, and the liquid is distributed and supplied to the ion selection electrode through the liquid supply hole at substantially the same time. Activity measurement method.