JPS6355023B2 - - Google Patents

Description

Detailed Description of the Invention The present invention is for measuring a sample that can be introduced into a capillary for measurement, and has an inlet and an outlet through which an electrolyte flows, a reference electrode inside, and a capillary and an electrolyte. Such a device is known, for example, from Austrian Patent No. 278,710, which relates to a capillary body with an electrolyte distribution chamber connected via a liquid bridge. In such mechanisms, the distribution chamber is integrated into a rotatable three-way switching valve. The three-way valve mentioned above is
Three switching states are possible: in the first state, both the entrance and exit of the distribution chamber are closed, in the second state, these holes are connected to the corresponding electrolyte channels, and in the third state, the electrolyte is closed. The inlet is closed and the outlet is connected to an opening located near the measuring capillary. Via the rotatable switching valve, it is thus possible to form an electrolyte bridge between the capillary channel through which the sample passes and the distribution chamber in which the reference electrode is located and, if necessary, to block it. The latter condition is essential for cleaning the sample capillary in the known configuration. In addition to the mechanical weakness of the rotating parts, this known device has the decisive problem that the distribution chamber is quite large, resulting in high electrolyte consumption and increased fouling of the chamber. Furthermore, depending on the structure of the above-mentioned known device, bubbles are likely to be generated due to temperature changes within the electrolyte solution, but the generated bubbles are difficult to escape and make the communication between the distribution chamber and the sample flow path unstable and unreliable. measurement becomes impossible.

The object of this invention is to improve the above-mentioned type of capillary body so as to avoid the above-mentioned problems of the known structure, and to quickly and reliably eliminate air bubbles that tend to occur in the above-mentioned mechanism for measurement. This is an attempt to eliminate the influence of

To achieve this, the present capillary body has an electrolyte inlet in the distribution chamber located at a lower position than the outlet when the capillary body is assembled, and a substantially conical shape is formed between the distribution chamber and the capillary tube to bridge the electrolyte. A communication channel is provided with a tip of which the opening in the vicinity of the capillary preferably corresponds to a hole of 0.01 to 0.1 mm. Due to the above-described unique mechanism of introduction and withdrawal of the electrolyte, harmful air bubbles in the distribution chamber with the reference electrode are continuously evacuated during operation of the device. When the sample is sucked into the capillary, a suction force is generated in the communication path through the above-mentioned tapered communication path for electrolyte bridging that opens into the capillary, and a suction force is generated within the communication path. A small amount of electrolyte, determined by the size of the pores, is sucked into the capillary itself. Any air bubbles or dirt that may remain in the communication channel are therefore drawn into the sample capillary channel by the subsequent inflowing electrolyte, and then into the sample, where the amount of electrolyte required for the measurement is absorbed. is introduced. The entire mechanism does not require any mechanically moving parts and the electrolyte consumption is at most 2~2~2 for each sample.
It can be formed to be limited to up to 3μ. Since the communication channel or the tip of the channel leading to the capillary pore is cleaned every time the electrolyte is withdrawn, the possibility of contamination and therefore of erroneous measurements is very small. be.

A further characteristic embodiment of the present invention is that the communication passage includes a connection port with a distribution chamber attached to the outside of the capillary body. This allows a free selection of the capillary body dimensions, since the distribution chamber is mounted externally with electrodes protruding into the interior of the chamber.

Another solution of the invention, which has proven to be advantageous in some applications, is that the distribution chamber is integrated into the capillary body itself, together with an inlet and an outlet for the electrolyte. According to this, the amount of electrolyte for bridging the electrolyte between the distribution chamber and the capillary tube can be kept very small, and furthermore, the amount of the electrolyte for bridging the electrolyte between the distribution chamber and the capillary tube can be kept very low, and the amount of connecting material or connecting parts for bridging the electrolyte between the distribution chamber and the capillary can be kept very low. All of that becomes useless.

In a particularly preferred embodiment of the present invention, the communicating pore to the capillary tube is formed with a hose tip material molded from a polymeric material, and the tip material is adhered to the communicating path in the vicinity of the capillary tube. They are joined in a reliable manner and have pear-shaped enlarged portions near the communicating pores. Experience has shown that a pear-shaped enlargement at the tip of such a passageway has an unexpected effect. That is, a portion of the sample may flow into the communication channel, but it is ensured that it remains within this enlarged section, which acts as a mixing chamber. Such an enlarged portion within the hose tip may be at most 2~
Since it is just something with a volume of 3μ,
When the electrolyte is later taken out, that is, when the next sample is drawn into the capillary, the inside of the tube is cleaned as sufficient electrolyte flows out. In particular, if a polymer hose material such as polyethylene or polytetrafluoroethylene is used for the hose tip material, virtually no sample remains on the wall surface of the enlarged portion. Furthermore, the pear-shaped enlarged portion at the tip of the hose can be formed very easily by heating the polymeric hose and stretching it appropriately. This is because materials such as those described above tend to expand in cross section rather than shrink under these conditions.

Now, as an embodiment of the present invention for simplifying the cleaning work required when the communicating pore connected to the capillary tube is blocked or for avoiding the above-mentioned blockage itself, a device similar to that described above is installed in the conical tip region of the communicating channel. Some devices incorporate a removable built-in body having a substantially conical tip, and a pore communicating with the capillary tube is formed between the tip of the built-in body and the tip of the communicating path. The advantage of this embodiment is that if the pores communicating with the capillaries become soiled or clogged, the assembly can be easily removed for easy cleaning. An even more decisive advantage is that the communicating pores with an almost annular cross-section
This is less likely to cause blockage due to a single impurity than when the capillary body has a circular cross section with the same cross-sectional area, and this has a favorable effect on the installation period of the disposable capillary body.

In a further characteristic embodiment of the invention, the tip of such an assembly has a smaller cone angle than the tip of the communication channel, which limits the flow rate and also influences the blockage of dirt. The smallest part of the communicating pores will be the one directly at the transition to the capillary.

Another measure of the present invention is that a plurality of longitudinal pleat grooves are formed at the conical tip of the built-in body, and the communication path and the conical tip of both ends of the built-in body are connected to each other. The size and shape of the free cross section of the pore communicating with the capillary tube can be selected within a wide range by simply changing the number, size, or structure of the grooves, without adjusting the attachment.

According to yet another measure of the invention, the built-in body can be adjusted in the axial direction between the distal end portion of the communication and the connecting body by means of a screw mechanism. According to the above, in addition to the above-mentioned advantages, the assembled body can be accurately positioned even if there is an error in manufacturing or assembly, so that the flow rate of the electrolyte through the communication channel can be adjusted according to the relative position between the two tips. Precise determination is possible through adjustment. In addition to the above, other conventional methods may be used to securely assemble the assembly within the communication passage, but of course, in all cases, such fixed assembly itself will ensure that the flow within the communication passage is not affected. Care must be taken to avoid interference.

Particularly, the present invention relates to a capillary body having a substantially disk shape, provided with a capillary tube passing through in the axial direction, and having a shape such that both ends can connect separate capillary bodies one after another. Yet another preferable solution is such that when the capillary body is assembled, the communicating path is substantially perpendicular to the capillary tube and connected from diagonally above. This method allows the bubbles generated in the electrolyte bridge to rise to the distribution chamber in an extremely simple and reliable manner, and furthermore, the bubbles are bubbled from the distribution chamber through the electrolyte introduction/removal mechanism disclosed in the present invention. is sent out continuously.

According to a still further preferred solution, an installation incorporating a capillary body according to the invention is provided with an electrolyte circulation path connected to the inlet/outlet of the distribution chamber, which circulation path is preferably provided with a pump, such as a peristaltic pump. In some cases, a gate valve is included before and after the distribution chamber, and an electrolyte storage container is also included. Since a certain amount of electrolyte is stored in the storage container, this invention, combined with the fact that electrolyte consumption is kept to a very small amount, allows automatic measurements to be carried out over a long period of time without any problems. You get it.

Next, the present invention will be described in more detail based on some embodiments shown in the drawings.

The capillary body 1 shown in FIG.
It has a structure in which similar capillary bodies are successively connected to both end faces of the capillary tube by a method not shown. A notch 4 is provided in the lower part of the disc-shaped capillary body 1 in the assembled state,
The cut is used for mutual alignment and fixed assembly of the capillary bodies having the above shape.

A sample introduced into the capillary tube 3 or hole;
A communication passage 5 is provided to form an electrolyte bridge with a distribution chamber (not shown), and this communication passage 5 preferably has a width of 0.01 to 0.1 mm in the vicinity of the capillary tube 3.
It has a capillary communicating pore 7 with a substantially conical tip 6 having a width of only . A hose connection port 8 is inserted into the outer end of the communication passage 5, and is used to communicate the communication passage 5 with a distribution chamber (not shown).

When the capillary body 1 is assembled, the communication passage 5 enters the capillary tube 3 substantially perpendicularly from diagonally above, and if air bubbles are generated in the communication passage 5 or its tip 6, , the bubbles rise within the electrolyte and are sent out through the distribution chamber entrance/exit of the present invention, which is not shown. When a sample is sucked into the capillary tube 3, a small amount of electrolyte is sucked from the communication path 5 or its tip 6 through the fine communication pores 7, so even if small bubbles are generated in the above-mentioned area, it will not occur again. leak at the same time.

The difference between the capillary body 1 shown in FIG. 2 and the one shown in FIG. It is that you are. The hose tip material 9 is preferably fixed in the vicinity of the capillary tube 3 in the communication path 5 by a reliable method such as adhesive, and has a pore 7 communicating with the capillary tube 3 of only 0.01 to 0.1 mm. It is something. FIG. 3 shows such a hose tip 9 enlarged. As shown in the figure, a pear-shaped enlarged portion 10 is provided near the communicating pore 7. This enlarged portion is easily formed by pulling a raw material hose made of a polymeric material and simultaneously heating it appropriately. This is because when the above-mentioned operation is performed on the above-mentioned material, the cross-section does not shrink but rather expands as shown.

In the mechanism according to the invention, the enlarged section 10 has great advantages. That is, even if a part of the sample is mixed in from the capillary tube 3 through its communicating pore 7, the enlarged portion acts as a mixing chamber and is reliably blocked. Since the volume of the enlarged part 10 is only 2 to 3 microns at most, when the electrolyte is taken out from this part next time, such dirt and small air bubbles that may occur in the communicating pores 7 will be removed. At the same time, it is sent back into the capillary tube 3. These things always happen. Particularly when using a hose material using a polymer such as polyethylene or polytetrafluoroethylene, there is virtually no sample remaining on the wall surface of the hose tip material 9.

FIG. 4 shows an example of a configuration including a control electrode, in which not only a conical tip 6 and a communication passage 5 for bridging an electrolyte with a communicating pore 7 but also a capillary 3 are connected to the capillary 3 through the communication passage for bridging an electrolyte. The connected distribution chamber 11 itself is built into the capillary body. Into the distribution chamber 11 a suitable output pole, preferably of the calomel type or of the Ag/AgCl type, is inserted, which is connected through a conductor 13 to signal processing and calculation electronics, not shown here.

The distribution chamber 11 is connected to an electrolyte circulation path (not shown), and when the capillary body is assembled, the electrolyte inlet is located at a lower position than the outlet in the distribution chamber 11. Both the electrolyte inlet 14 and the outlet 15 are provided with a hose connection port 8 for connection to the electrolyte circulation path. Due to the mechanism of the electrolyte inlet/outlet section in the distribution chamber 11 as described above, together with the advantages of the communication passage 5 or the communication pore 7 with the capillary tube 3 as described above, air bubbles that impair the reliability of measurement results are generated. can be prevented from remaining in the electrolyte bridge by a simple method.

The measurement equipment shown in FIG. 5 incorporates a capillary body 1 according to the present invention, constructed in the same manner as described above, and equipped with a capillary reference electrode, for example sensitive to different ions. These are summarized in Unit 17. When a negative pressure is applied to the hose 18, the sample is introduced into the unit 17 from the direction of the arrow 19. The distribution chamber 11 in the illustrated embodiment is assembled outside the capillary body 1, and the hose portion 2
It is connected to the communication path 5 in the capillary body 1 via the capillary body 1 . An output electrode 12 is inserted into the distribution chamber 11 and connected to a signal processing arithmetic device by a method not shown.

The distribution chamber 11 furthermore has an inlet 14 and an outlet 15 for its electrolyte circulation, although the configuration of the connections is only shown conceptually here.

Two hose valves 21, one peristaltic pump 22, and a hose are assembled into the electrolyte circulation path made of elastic hoses via connectors 23, and are also used for electrolyte storage. A container 24 is also included.

According to the above-mentioned mechanism of the present invention, since the electrolyte consumption for each measurement is small and a storage container is provided, it is possible to automatically perform a very large number of measurements continuously. The mechanism that prevents the generation of bubbles within the liquid bridge increases the precision and reproducibility of each measurement, producing very good results.

In yet another embodiment shown in FIG. 6, the capillary body 1 is formed substantially in the shape of a disk,
It is provided with a capillary tube 3 penetrating in the axial direction, and is configured such that similar capillary bodies are connected in succession via a centering projection 25. In the state shown in the figure, cuts 4 are provided in the lower part of the disk-shaped capillary body 1, and these cuts are used for mutual alignment of several capillary bodies and for common fixation assembly. .

In the illustrated embodiment, a communication passage 5 is provided for bridging the electrolyte between the distribution chamber 11 built into the capillary body 1 and the capillary tube 3, and the communication tube has a substantially conical shape near the capillary tube 3. It has a shaped tip 6.
A built-in body 27 having a similar conical tip 28 at a position corresponding to the conical tip 6 of the communication passage 5
is assembled into the communication path 5 via a screw mechanism 26.

In the communication passage 5, the inlet is located at a lower position than the outlet, and the inlet and outlet are each provided with a hose connection port 8 fitted on the outside of the capillary body 1. Therefore, the inflow of the electrolytic solution into the distribution chamber 11 occurs at a lower point than the outflow in the assembled state of the capillary body, and the air bubbles that tend to be generated in the corresponding area can be reliably sent out in a simple manner. .
A suitable output electrode 12 is inserted into the ceiling of the distribution chamber 11 and sealed by a sealing ring 29.

The tip 28 of the built-in body 27 has a cone angle smaller than the tip of the communication path 5, and
7 and the communication passage 5 forms the communication pore 7, which has an annular cross section perpendicular to the axis of the integrated body at the opening of the communication passage 5 toward the capillary tube 3. . The cross-sectional area of the communicating pore 7 can be easily changed by rotating the built-in body 27 using the screw mechanism 26. Therefore, manufacturing and assembly errors can be tolerated to a large extent. In order to facilitate rotation, a groove 30 shown in FIGS. 7 and 8 is provided in the ceiling of the built-in body 27 for the insertion of a screwdriver.
In both Figures 7 and 8, a notch 31 is shown at the thread groove 26 portion of the assembled body, and this is for securing a flow path at the thread groove 26 portion within the communicating path 5.

If a blockage occurs in the communication pore 7, the built-in body 27 can be easily removed, so that both the distal end 28 of the built-in body and the distal end 6 of the communication passage can be properly cleaned. In this case, since the cross-section of the flow path is annular, blockage is less likely to occur even if the communicating pores have a very small cross-sectional area.

FIG. 7 shows a conical tip 28 of the built-in body 27.
A plurality of longitudinally extending corrugated grooves 32 are shown formed therein. In this example, even if the tip 28 is completely pushed into the tip 6 of the communication path 5, it will not be blocked because the plurality of communicating pores 7 are formed at certain intervals.

Finally, in place of the notch 31, it is also possible to ensure free circulation within the communication path 5 by using, for example, a through hole provided in the upper part of the built-in body or in the threaded part inside the communication path. It is.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the capillary body of the present invention, FIG. 2 is a sectional view showing another embodiment of the present invention, and FIG. 3 is a sectional view of the capillary body of the present invention.
FIG. 4 is a diagram showing still another aspect of the present invention, FIG. 5 is a diagram showing a measurement equipment incorporating a capillary body according to the present invention, and FIG. 6 is a diagram showing a further embodiment of the present invention. A sectional view showing yet another aspect,
FIG. 7 is an enlarged view of the assembled body in FIG. 6, and FIG. 8 is a view taken in the direction of the arrows in FIG. 1...Capillary body, 3...Capillary tube, 5...Communication path, 7
... Communication pore, 9 ... Hose tip material, 11 ... Distribution chamber, 12 ... Reference electrode, 14 ... Electrolyte inlet, 15 ... Electrolyte solution outlet, 17 ... Measurement unit.

Claims (1)

[Scope of Claims] 1. A capillary body for measuring a sample introduced into a capillary tube, comprising an electrolyte distribution chamber equipped with a reference electrode;
An electrolyte bridging communication passage is provided between the distribution chamber and the capillary tube and has a conical tip that becomes a communication pore for the capillary tube in the vicinity of the capillary tube, and the distribution chamber has an electrolyte inlet and an electrolyte solution inlet. A capillary body for a capillary reference electrode, characterized in that an outflow port is arranged such that the inflow port is lower than the outflow port when the capillary body is assembled. 2 The capillary communicating pores are substantially 0.01 to 0.1
A capillary body for a capillary reference electrode according to claim 1, having a diameter of mm. 3. The capillary body has a hose port for connection to the electrolyte bridging communication path, and communicates with the electrolyte distribution chamber provided outside via the connection hose port. A capillary body for a capillary reference electrode according to item 1. 4. A capillary body for a capillary reference electrode according to claim 1, wherein the distribution chamber is incorporated into the capillary body itself together with an electrolyte inlet, an electrolyte outlet and a communication passage for electrolytic crosslinking. 5. A patent characterized in that a nozzle tip material molded from a polymeric material is disposed within the electrolyte bridging communication passage, and has a pear-shaped cross-section enlarged in the vicinity of the capillary communication pore. A capillary body for a capillary reference electrode according to any one of claims 1 to 4. 6. A removable built-in body having a substantially conical tip is provided in the conical tip region of the electrolyte bridging communication passage, and the distal end of the built-in body and the distal end of the electrolyte bridging communication passage are connected to the 5. A capillary body for a capillary reference electrode according to any one of claims 1 to 4, characterized in that the capillary body has a pore communicating with the capillary. 7. The capillary body for a capillary reference electrode according to claim 6, wherein the distal end of the assembled body has a smaller cone angle than the distal end of the electrolyte bridging communication path. 8. The capillary body for a capillary reference electrode according to claim 6 or 7, characterized in that the conical tip portion of the built-in body has a plurality of pleated grooves in the longitudinal direction. 9. The capillary reference according to any one of claims 6 to 8, wherein the assembled body is adjustable in axial position with respect to the distal end of the electrolyte bridging communication path by a screw mechanism. Capillary body for electrodes. 10 A capillary body having a substantially disk shape, having a capillary tube penetrating in the axial direction, and having a shape such that both end faces can connect separate capillary bodies in sequence, and in an assembled state, the electrolyte bridging communication passage is 5. The capillary body for a capillary reference electrode according to claim 4, wherein the capillary body is connected from diagonally above, substantially perpendicular to the capillary tube. 11. An electrolyte circulation path including a pump, an electrolyte storage container, and/or a gate valve attached to each of the upstream and downstream sides of the distribution chamber is connected to the entrance/exit of the electrolyte distribution chamber. A capillary body for a capillary reference electrode according to any one of claims 1 to 10.