WO2007052377A1

WO2007052377A1 - Micropump and micro fluid chip

Info

Publication number: WO2007052377A1
Application number: PCT/JP2006/306547
Authority: WO
Inventors: Shunro Nishiwaki; Kenichi Tayama; Kiyohide Maguchi; Tomiiti Hasegawa; Toshio Yoshida; Yudai Furukawa
Original assignee: Niigata Tlo Corporation
Priority date: 2005-11-02
Filing date: 2006-03-29
Publication date: 2007-05-10
Also published as: JP4528330B2; JPWO2007052377A1

Abstract

[PROBLEMS] To improve operability of a micropump for very low flow rate utilizing a membrane permeation flow caused by electric effect of a flow passing through a micro region. [MEANS FOR SOLVING PROBLEMS] A micropump for very low flow rate comprising a shell having a through hollow portion, and a porous membrane interposed between a plus electrode and a minus electrode and so arranged in the hollow portion as to divide it into two, and utilizing electroosmosis effect of a flow passing through the porous membrane, characterized in that a bypass channel for filling liquid is arranged to communicate with the lower space of the hollow portion divided into two by the porous membrane, and an air vent channel is arranged to communicate with the atmosphere from the lower space. In the micropump, the inlet of the air vent channel opening to the inside of the lower space has a height from the bottom face of the lower space which is preferably set to be larger than the height of the outlet of the bypass channel opening to the inside of the lower space from the bottom face of the lower space.

Description

Technical field

The present invention relates to a micro flow micro pump and a micro fluid chip using the pump. More specifically, the present invention relates to a micro-flow micropump excellent in operability and a microfluidic chip in which the pump can be detachably disposed.

Background art

[0002] Recently, micro-channels, reaction vessels and ports, etc. have been built into the substrate, as known under the name Micro 'Total' Analysis' Systems (TAS) or Love 'on-Chip'. A microdevice configured to perform various operations such as chemical reaction, synthesis, purification, extraction, generation and Z or analysis of a substance in a microstructure is proposed and partially put into practical use. Yes. A structure having a microstructure such as a microchannel, a port, and a reaction vessel manufactured for such a purpose is collectively called a “microfluidic chip” or simply “microchip”. The material, structure, and manufacturing method of the microfluidic chip are disclosed in, for example, Patent Document 1 and Patent Document 2.

[0003] A microchannel or reaction vessel in a microfluidic chip handles a fluid (mainly a liquid such as a chemical solution or a sample). For this purpose, a function for controlling the flow and transfer of the fluid is required. In particular, a small functional component built in a microfluidic chip is called a fluid control element. Common fluid control elements include microvalves and micropumps.

An example of a micropump used for a microfluidic chip is described in Patent Document 3. This micropump is a micropump for micro flow rate that uses the flow through the membrane by the electrical effect passing through the micro region. As shown in FIG. 19, the micropump 200 of Patent Document 3 is sometimes used while being placed on the upper surface of the microfluidic chip 1. The PDMS substrate 3 in the microfluidic chip 1 is formed with a fine channel 5 and ports 7 and 9 communicating with the fine channel. For example, a glass facing substrate 10 is permanently bonded to the lower surface side of the PDMS substrate 3. The micro pump 100 is placed on the upper surface of the port 7. The micropump 200 has an outer shell 203 and a positive electrode 2 built in the outer shell 203. 05 and a negative electrode 207 and a porous membrane 209 interposed between the electrodes. A liquid storage space 211 is formed in the upper part of the plus electrode 205, and a tube 213 for feeding the liquid into the liquid storage space 211 is fixed with an appropriate adhesive.

FIG. 20 is an exploded perspective view of the positive electrode 205 and the negative electrode 207 shown in FIG. 19 and the porous film 209 interposed between the electrodes. The porous membrane 209 is actually supported by the support 217. Circular openings 219 and 221 are disposed on the plus electrode 205 and the minus electrode 207, respectively. The circular openings 219 and 221 have substantially the same radius as the circular opening of the support 217, i.e. the circular region where the porous membrane 209 faces the flow, and all centers are on the same axis. It is located.

[0006] When a voltage of several VDC to several tens of volts (for example, 5V to 15V) is applied between the electrodes 205 and 207 around the porous membrane 209, the liquid flows toward the positive electrode 205 side minus the electrode 207 side. . Accordingly, the liquid in the liquid storage space 211 passes through the porous membrane and is pushed out into the port 7. The flow rate by the porous membrane pump can be varied by 0. 02mm ^³ Zs~0. 14mm ³ Zs of within range. The flow rate is roughly proportional to the applied voltage. The advantage of using such a micropump is that no pulsating flow occurs.

FIG. 21 is a partial schematic cross-sectional view showing a usage example of the conventional micropump 200 as shown in FIG. The conventional micropump 200 uses the driving liquid 223 supplied from the tube 213 into the liquid storage space 211 to push out another sample liquid 225 prefilled in the port 7 to the fine channel 5 and send it. May be used for liquefaction purposes. In this case, if the driving liquid 223 is not filled in the space 215 between the lower electrode 207 and the port 7, the sample liquid in the port 7 cannot be pushed out and sent to the microchannel 5. . Force due to the volume of the space 215 As mentioned above, the flow rate by the porous membrane pump is about 0.1 μLZs to 100 μLZs, so it takes a considerable time to fill the space 215 with the driving liquid 223. This could delay analysis work.

Patent Document 1: Japanese Patent Application Laid-Open No. 2000-27813

Patent Document 2: Japanese Patent Laid-Open No. 2001-157855

Patent Document 3: International Publication No. 2005Z052379 Pamphlet

Disclosure of the invention Problems to be solved by the invention

Accordingly, an object of the present invention is to improve the operability of a micro pump for micro flow rate using a flow through a membrane by an electrical effect passing through a micro region.

Means for solving the problem

[0010] The invention of claim 1 as a means for solving the above-mentioned problems is arranged such that an outer shell having a through-hole and a hollow part are vertically divided into the hollow part. In a micro flow micropump comprising a porous membrane interposed between a plus electrode and a minus electrode and utilizing an electroosmotic flow effect passing through the porous membrane,

A liquid-filling bypass flow path communicating with the lower space of the hollow portion divided by the porous membrane is disposed, and an air vent flow path communicating with the atmosphere from the lower space is disposed! / Provided is a micropump characterized by squeezing.

[0011] According to the present invention, the liquid such as the driving liquid is rapidly passed through the liquid filling bypass channel communicating with the lower space of the hollow portion divided into two by the porous membrane of the outer shell of the micropump. The lower space can be filled. At this time, the air in the lower space escapes to the atmosphere through the air vent flow path, so that there is no obstacle to filling the lower space with liquids such as driving liquid. As a result, it becomes possible to fill the lower space with a liquid such as a driving liquid in an extremely short time, and like a conventional micropump, a voltage is applied to the lower space for a long time. Since the slow and redundant operation filled with liquids is no longer necessary, the operability or use of the micropump can be dramatically improved.

[0012] The invention of claim 2 as means for solving the above-mentioned problem is that the height of the inlet of the air vent channel that opens to the inside of the lower space from the bottom surface of the lower space is the lower space. 2. The micropump according to claim 1, wherein a height of the outlet of the bypass channel opened inside is lower than a bottom surface of the lower space.

[0013] According to the present invention, since the height of the lower space outlet of the liquid-filling bypass channel is equal to or higher than the height of the lower space inlet of the air vent channel, the air in the lower space is surely received. It can be guided to the air vent channel.

[0014] The invention of claim 3 as means for solving the above-mentioned problem is that the bypass flow path is formed outside the outer shell or in the wall of the outer shell, and the air vent flow path is the outer shell. Outside The microphone port pump according to claim 1 or 2, wherein the microphone port pump is formed in a wall of the outer shell or the outer shell.

[0015] According to the present invention, the bypass channel can be formed outside the outer shell or in the wall of the outer shell, and the air vent channel can also be formed outside the outer shell or in the wall of the outer shell. So you can choose a convenient combination.

[0016] The invention of claim 4 as a means for solving the above-mentioned problem is that the bypass flow path formed outside the outer shell is disposed through the lower space of the outer shell. A second hole serving as a bypass channel outlet, a first groove whose lower end communicates with the second hole, and a first shielding sheet that shields the second hole and the first groove; The first groove is formed on either the outer wall surface of the outer shell or the adhesive surface side of the first shielding sheet, and the upper end of the first groove Is communicated with the first hole disposed through the upper space of the outer shell and shielded by the first shielding sheet, or communicated with the atmosphere at the upper end of the first shielding sheet. And

The air vent channel formed outside the outer shell has a third hole serving as an air vent channel inlet penetrating the lower space of the outer shell, and a lower end of the third hole. A second groove that communicates with the second hole and a second shielding sheet that shields the third hole and the second groove, and the second groove is formed on the outer wall surface of the outer shell. Or the upper end of the second groove is disposed so as to penetrate through the upper space of the outer shell, and the second shielding sheet is attached to the second shielding sheet. Communicating with the fourth hole shielded by the shielding sheet, or communicating with the atmosphere at the upper end of the second shielding sheet,

The height of the third hole from the bottom surface of the lower space is equal to or higher than the height of the second hole from the bottom surface of the lower space,

When the first groove communicates with the first hole and the second groove communicates with the fourth hole, the position of the first hole of the lower space bottom force is the fourth position from the bottom of the lower space. 4. The micropump according to claim 3, wherein the position is lower than the position of the hole.

[0017] According to the present invention, the bypass flow channel or the air vent flow channel can be formed outside the outer shell in various modes, so that a convenient mode can be appropriately selected.

[0018] The invention of claim 5 as a means for solving the above-mentioned problems is formed in the wall of the outer shell. The bypass channel formed is composed of a second hole serving as a bypass channel outlet disposed in a lower space of the outer shell and a first groove, and a lower end of the first groove is The upper end of the first groove communicates with the atmosphere on the upper end surface of the outer shell, or opens to the inner side of the upper space of the outer shell. Or communicates with a first hole that opens toward the outside of the outer shell,

The air vent channel formed in the wall of the outer shell includes a third hole serving as an air vent channel inlet disposed in a lower space of the outer shell and a second groove, and the second groove. The lower end of the groove communicates with the third hole, and the upper end of the second groove communicates with the atmosphere on the upper end surface of the outer shell, or the upper space of the outer shell. It opens to the inside by force or communicates with the fourth hole that opens to the outside of the outer shell,

The first groove communicates with the first hole opening toward the inside of the upper space of the outer shell, and the second groove opens to the inside of the upper space of the outer shell. 4. The micropump according to claim 3, wherein, when communicating with the hole, the position of the first hole from the bottom surface of the lower space is lower than the position of the fourth hole of the bottom space bottom force.

According to the present invention, the bypass channel or the air vent channel can be formed in the wall of the outer shell in various modes, so that a convenient mode can be appropriately selected.

[0020] The invention of claim 6 as means for solving the above-mentioned problem is that the inner diameter force of the inlet (third hole) of the air vent channel opened inside the lower space is opened inside the lower space. The micropump according to any one of claims 1 to 5, wherein the micropump is larger than an inner diameter of an outlet (second hole) of the bypass flow path.

[0021] According to the present invention, since the inner diameter of the inlet (third hole) of the air vent channel is larger than the inner diameter of the outlet (second hole) of the bypass channel, bubbles are introduced into the inlet of the air vent channel. Escape to the atmosphere smoothly without stagnating in the (third hole).

[0022] The invention according to claim 7 as means for solving the above-mentioned problem is that the shape of the first groove and the second groove is any shape selected from the group consisting of a linear shape and a meandering shape. The micropump according to any one of claims 1 to 6, wherein the micropump is provided. [0023] According to the present invention, the shape of the groove can be selected as a straight line or a meandering shape as appropriate, and the shape can be selected. It has the advantage that it can be done.

[0024] The invention of claim 8 as means for solving the above-mentioned problem is that the outer shell is formed of polydimethylsiloxane (PDMS) or glass, and the first shielding sheet and the second shielding sheet. The micropump according to any one of claims 1 to 7, wherein PDMS force is also formed.

[0025] According to the present invention, the PDMS shielding sheet can be self-adsorbed to the outer wall surface of the outer shell by forming the outer shell with PDMS or glass force.

[0026] The invention of claim 9 as means for solving the above-mentioned problem further comprises a diaphragm for closing the lower space in the vicinity of the end of the lower space of the outer shell. A micropump according to any one of -8 is provided.

[0027] According to the present invention, when the driving liquid and the sample liquid cannot form a clear interface and are mixed with each other, a buffer solution is conventionally interposed between the driving liquid and the sample liquid.力力 The driving force of electroosmotic flow can be transmitted to the sample liquid through the diaphragm without using a buffer solution. As a result, all the various problems associated with the use of buffer solutions can be solved.

[0028] The invention of claim 10 as means for solving the above-mentioned problems is arranged such that the outer shell having a through-hole and a hollow portion are divided into two in the vertical direction inside the hollow portion. In a micro flow micropump comprising a porous membrane interposed between a plus electrode and a minus electrode and utilizing an electroosmotic flow effect passing through the porous membrane,

There is a diaphragm for sealing the upper space in the vicinity of the end of the upper space of the hollow portion divided into two by the porous membrane, and near the end of the lower space of the hollow portion divided into two by the porous membrane There is provided a micropump having a diaphragm for sealing the lower space, and the sealed upper space and lower space are filled with a predetermined amount of driving liquid, respectively.

According to the present invention, the driving liquid is hermetically filled in the upper space and the lower space, respectively. Apply a voltage between the electrodes to reduce the amount of driving fluid in the upper space with a large amount of driving fluid. After moving the sample solution to the lower space with the drive liquid, turn the micropump over to make the lower space with a large amount of drive liquid the upper space, and the upper part where the drive liquid is low If the space is placed in the original port opening as the lower space and a voltage is applied between the electrodes, the driving liquid can be moved from top to bottom again. As a result, complicated driving liquid supply operation can be omitted, and the driving liquid is completely prevented from being contaminated or denatured by dust, microorganisms, carbon dioxide, etc. in the atmosphere. Since the replacement or replenishment of the drive fluid is unnecessary, it is possible to save the cost of the drive fluid. The overall device configuration is simplified, and the device cost is also reduced.

[0030] The invention of claim 11 as a means for solving the above-mentioned problems is made of polydimethylsiloxane having one or more ports opened to the atmosphere and a fine channel communicating with the ports. Over a microfluidic chip comprising a substrate and a counter substrate bonded to the surface of the polydimethylsiloxane substrate that is bonded to the fine channel,

A microfluidic chip, wherein the micropump according to any one of claims 1 to 10 is detachably mounted on an upper surface of an opening of at least one of the ports.

[0031] According to the present invention, after the microfluidic chip is used, by removing the PDMS substrate force micropump, these micropumps can be reused in another microfluidic chip, which greatly reduces the cost. Can be realized.

[0032] The invention of claim 12 as means for solving the above-mentioned problems is characterized in that a sample solution replenishment path for replenishing a sample solution in the open port on a substrate on which the open port is formed, 12. The microfluidic chip according to claim 11, further comprising an air vent path for venting air from the open port.

[0033] According to the present invention, by using the sample solution replenishment path, the sample solution can be directly replenished into the port while the micro-bump remains mounted on the port. , Air venting path force Since air is vented, stable micropump operation is performed.

[0034] The invention of claim 13 as means for solving the above-mentioned problems is that the sample solution replenishment path has an open / close valve and a replenishment pump for feeding a sample solution from a sample solution tank into the port. Provided to control the on-off valve and the replenishment pump when replenishing the sample solution. 13. The microfluidic chip according to claim 12, further comprising a control device.

[0035] According to this invention, the control device automates the replenishment of the sample solution by operating the on-off valve provided in the sample solution replenishment path and the replenishment pump.

The invention's effect

[0036] According to the micropump of the present invention, the liquids such as the driving liquid are rapidly lowered through the liquid filling bypass passage communicating with the lower space of the hollow portion divided into two by the porous membrane of the outer shell. The partial space can be filled. At this time, the air in the lower space escapes to the atmosphere through the air vent flow path, so that it does not become an obstacle when filling the lower space with liquids such as driving liquid. As a result, it becomes possible to fill the lower space with a liquid such as a driving liquid in an extremely short time, and like a conventional micropump, a voltage is applied to the lower space over a long period of time. Since the slow and redundant operation of filling liquids is no longer necessary, the operability or usability of the micropump can be dramatically improved.

[0037] If the driving liquid and the sample liquid cannot form a clear interface and are mixed with each other, a buffer solution is conventionally interposed between the driving liquid and the sample liquid. By disposing the diaphragm at the end of the space, the driving force of the electroosmotic flow can be transmitted to the sample liquid through the diaphragm without using a buffer solution. As a result, all the various problems associated with the use of buffer solutions can be solved.

[0038] Furthermore, by sealing each of the upper space and the lower space with a diaphragm and filling each sealed space with a predetermined amount of driving liquid, not only the complicated driving liquid supply operation can be omitted, but also the driving liquid can be removed. Pollution and alteration by atmospheric dust, microorganisms, carbon dioxide, etc. are completely prevented. Since it is not necessary to put in and out the drive fluid, or to replace or replenish the drive fluid, not only can the cost for the drive fluid be saved, but the overall device configuration is simplified, resulting in a lower device cost.

[0039] Further, by forming the outer shell of the micropump with PDMS or glass, it becomes possible to self-adsorb to the PDMS substrate of the microfluidic chip, and even if the microfluidic chip itself is discarded after use. The micropump of the present invention can be reused any number of times by allowing it to self-adsorb on another new microfluidic chip. As a result, expensive The cost of a simple micropump is greatly reduced and extremely economical.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings. FIG. 1 is a schematic sectional view of an example of a micropump 20 according to the present invention. As shown in FIG. 1, the micropump 20 of the present invention is basically disposed between the outer shell 23, the upper electrode 25, and the lower electrode 27 in the same manner as the conventional micropump shown in FIGS. And an interstitial porous membrane 29. Further, the electrode-equipped porous membrane 29 is arranged so that the hollow portion of the outer shell 23 is divided into two vertically, and as a result, an upper space 31 and a lower space 33 are formed with the electrode-equipped porous membrane 29 as a boundary. The Although not shown, the upper electrode 25 is connected to the positive side of the DC power source, and the lower electrode 27 is connected to the negative side of the DC power source. However, depending on the purpose, plus and minus can be reversed. The outer shell 23 is sometimes called a pump holder. In order to allow the micropump 20 to be stably placed on the upper surface of the microfluidic chip 1 (see FIG. 19), the lower part of the outer shell 23 is formed with a flange portion 35 having an enlarged outer diameter and having a predetermined thickness. It is preferable. However, the arrangement of the flange portion 35 is not an essential requirement of the present invention. The outer shell 23 is preferably formed from PDMS. When the outer shell 23 is made of PDMS, the micropump 20 can be self-adsorbed to the PDMS substrate 3 by placing it on the upper surface of the port 7 of the PDMS substrate 3 of the microfluidic chip 1. As a result, the micropump 20 can be detached from the PDMS substrate 3. In a conventional micro-mouth fluid chip, the micropump and the like are discarded together with the chip after use. However, according to the present invention, the micropump 20 is detached from the PDMS substrate 3 after the microfluidic chip 1 is used. As a result, these micropumps 20 can be reused in another microfluidic chip, and a significant cost reduction can be realized.

In FIG. 1, a first hole 37 that penetrates the side wall on the upper space 31 side of the outer shell 23 is opened, and a second hole 39 that penetrates the side wall on the lower space 33 side is opened. A first groove 41 having a predetermined width and depth for communicating the first hole 37 and the second hole 39 is provided on the outer wall surface of the outer shell 23. The first hole 37, the second hole 39, and the first groove 41 can be formed by known and conventional means. The first shielding sheet 43 covering the first hole 37, the second hole 39, and the first groove 41 is adhered to the outer wall surface of the outer shell 23. 1st hole 37 and 2nd hole 39 sealed with this shielding sheet 43 The first groove 41 constitutes a liquid-filling bypass channel that communicates between the upper space and the lower section. The inner diameters of the first hole 37 and the second hole 39 may be lmm as an example. Other inner diameters can be employed. The material of the first shielding sheet 43 is not particularly limited. In order to enable self-adsorption with the outer shell 23 made of PDMS, the first shielding sheet 43 is also preferably formed from PDMS. The thickness and size of the first shielding sheet 43 are not particularly limited. The thickness and the size are sufficient to seal the first hole 37, the second hole 39, and the first groove 41. The no-pass channel is not limited to the driving liquid for the micropump, but can also be used for filling liquids such as liquid reagents and samples.

In FIG. 1, a fourth hole 47 is formed through the side wall of the outer shell 23 on the upper space 31 side at a position different from the first hole 37. Similarly, a third hole 45 penetrating the side wall on the lower space 33 side is formed at a position different from the second hole 39. A second groove 49 having a predetermined width and depth that allows the third hole 45 and the fourth hole 47 to communicate with each other is disposed on the outer wall surface of the outer shell 23. The third hole 45, the fourth hole 47, and the second groove 49 can be formed by a known and conventional method. The inner diameter of the fourth hole 47 can be lmm as an example. The inner diameter of the third hole 45 can be 2 mm as an example. If the inner diameter of the third hole 45 is smaller than the outer diameter of the bubble, there is a possibility that bubbles will accumulate around the third hole 45 and will not be discharged. In order to efficiently vent the air, the inner diameter of the third hole is preferably larger than the inner diameters of the other holes. Needless to say, other inner diameters can be used. A second shielding sheet 51 that covers the third hole 45, the fourth hole 47, and the second groove 49 is adhered to the outer wall surface of the outer shell 23. The third hole 45, the fourth hole 47, and the second groove 49 sealed by the second shielding sheet 51 constitute an air vent channel for extracting the air in the lower space into the atmosphere. The material of the second shielding sheet 51 is not particularly limited, but the second shielding sheet 51 is also preferably made of PDMS so that it can self-adsorb with the PDMS outer shell 23. The thickness and size of the second shielding sheet 51 are not particularly limited. Have enough thickness and size to seal the third hole 45, the fourth hole 47 and the second groove 49 !.

What is important is that the fourth hole 47 is located above the height of the first hole 37. If the height position of the fourth hole 47 is the same as or lower than the height position of the first hole 37, the fourth hole 47 is below the level of the driving liquid filled in the upper space 31. And air vent flow I can't serve as a road.

[0044] The height position of the third hole 45 may be the same force as the height position of the second hole 39, or above it. In FIG. 1, the height position of the third hole 45 is higher than the height position of the second hole 39, but the electrode-equipped porous film 29 is inclined, and the upper portion of the porous film 29 is inclined. Is positioned so as to be substantially the same as the height of the third hole 45, the air in the lower space 33 is guided to the third hole 45 along the slope of the porous membrane 29 and completely and smoothly in the atmosphere. Will not be able to stay in the lower space 33.

[0045] The first groove 41 that allows the first hole 37 and the second hole 39 to communicate with each other can be formed in a straight line as shown in FIG. 2 (A), but FIG. 2 (B) It can also be formed in a meandering shape as shown in FIG. Compared to the straight groove, the meandering groove has an advantage that the pressure loss can be controlled because the entire distance of the groove becomes longer. As a result, it is possible to effectively prevent a disadvantageous situation in which the driving fluid flows backward from the lower space 33 to the upper space 31. The number of times of meandering is not limited to the illustrated embodiment, and any number of times can be selected. Further, the meandering is not limited to the crank shape as shown in the figure, but may be a curved shape having a predetermined curvature. Although not specifically shown, the second groove 49 for communicating the third hole 45 and the fourth hole 47 is also completely different from the embodiment shown in FIGS. 2 (A) and 2 (B). It can be configured similarly. The width and depth of the first groove 41 and the second groove 49 can be selected as appropriate within a range of several tens / z m to several hundred μm, for example. The lengths of the first groove 41 and the second groove 49 can be appropriately selected within a range of several mm to several tens of mm.

[0046] Alternatively, instead of disposing the first groove 41 and the second groove 49 on the outer wall surface of the outer shell 23, as shown in FIG. The first groove 41A (or the second groove 49A) can also be formed on the bonding surface side of the shielding sheet 51A). In this case, the first groove 41A (or the second groove 49A) is formed on the first shielding sheet 43A (or the second shielding sheet 51A) by a known photolithography method using a resist mold or the like. It can be easily formed on the adhesive side. The first groove 41A (or the second groove 49A) is easily aligned with the first hole 37 and the second hole 39 (or the third hole 45 and the fourth hole 47) at both ends of the first groove 41A (or the second groove 49A). In order to achieve this, the recesses 53 and 55 can be formed. However, this recess may be omitted. A portion of groove 41A (or 49A) is connected to first hole 37 and second hole 39 (or third hole 45 and fourth hole 47). If crossed, it is a force that can function as a bypass passage for driving liquid filling (or an air vent passage).

[0047] FIG. 4 shows the first shielding sheet 43A and the second shielding sheet 51A having the first groove 41A and the second groove 49A shown in FIG. FIG. 5 is a cross-sectional view of a state where it is adhered to 23A, and FIG. 5 is a perspective view thereof.

FIG. 6 is a schematic plan view of another embodiment of the second shielding sheet, and FIG. 7 is a partial schematic sectional view of a micropump of the present invention using the second shielding sheet. As shown in FIG. 6, in the second shielding sheet 51B, the upper end side of the second groove 49B extends to the end portion of the sheet to form an air outlet 57. As a result, there is no need to provide a fourth hole 47 that penetrates the air in the side wall of the upper space 31 of the outer shell 23B.

FIG. 8 is a partial schematic cross-sectional view of another embodiment of the micropump of the present invention. In this embodiment, in the first shielding sheet 43B, the upper end side of the first groove 41B is extended to the upper end portion of the sheet to form a liquid (for example, driving liquid) injection port 59. Therefore, since it is not necessary to drill the first hole 37 for injecting liquid into the bypass channel in the side wall of the upper space 31 of the outer shell 23C, not only the manufacture of the micropump is facilitated, but also the liquid inlet By inserting a syringe into 59, liquid can be easily fed into the lower space 33.

FIG. 9 is a partial schematic cross-sectional view of still another embodiment of the micropump of the present invention. In this micropump 20D, the first groove 41C serving as a no-pass channel for feeding liquids such as driving liquid to the lower space 33 and the second groove 49C serving as an air vent channel are formed in the outer shell 23D. Located in the wall. Accordingly, in this embodiment, the second hole 39 and the third hole 45 have only a length that reaches the first groove 41C and the second groove 49C that are not through holes. According to this embodiment, since it is not necessary to use the first shielding sheet and the second shielding sheet, the micropump 20D having a clean structure can be obtained. The liquid inlet 59 and the air outlet 57 are both open on the upper end surface of the outer shell 23D, but the present invention is not limited to this, and the first hole communicating with the first groove 41C is provided in the upper space. It can be opened to the inside, or can be opened to the outside of the outer shell by force, and similarly, the fourth hole communicating with the second groove 49C can be opened to the inside of the upper space, Or open the outer shell by force. Tochidaru.

FIG. 10 is a partial schematic cross-sectional view of still another embodiment of the micropump of the present invention. In the micropump 20E, a diaphragm 61 is disposed near the lower end of the lower space 33. For example, the diaphragm 61 can be fixed to the inner wall of the lower end of the lower space 33 by an annular diaphragm holder 62. Needless to say, the diaphragm 61 can be disposed in the microphone port pump 20E by a mode other than that illustrated. The diaphragm 61 also forms a material force having flexibility or flexibility such as a thermoplastic synthetic resin (eg, polyethylene, polyester, nylon, methyl methacrylate) or rubber (eg, silicone rubber, latex rubber, etc.). It is preferable that The film thickness of the diaphragm 61 is 0.03mn! ~ Lmm or so. The shape of the diaphragm 61 is not limited to the dome shape having an elliptical cross section as shown in the figure, but the volume of the protruding portion can be changed by changing the shape of the diaphragm, which may be circular, cone-shaped or irregular. Anything that can be done! ,.

[0052] If the driving liquid and the sample liquid do not form a clear interface and are mixed with each other, it is necessary to use a buffer solution to separate the driving liquid and the sample liquid. However, the following problems exist in the use of buffer solutions.

(a) the buffer may alter or contaminate the sample liquid;

(b) Separation with the buffer solution may not be successful, and in some cases the drive solution may be contaminated by mixing with the sample liquid;

( _c ) When starting the micropump, replenishing the sample liquid, performing maintenance, etc., the three types of liquids must be removed and handled, and the work becomes complicated; and

(d) It is necessary to provide a special pipe line to hold the buffer solution, the structure becomes complicated, and it becomes difficult to incorporate it into the microphone tip.

As shown in FIG. 10, the use of the diaphragm 61 in the micropump of the present invention makes it unnecessary to use a buffer, and as a result, all the problems (a) to () are solved.

[0053] The electrode-containing porous membrane 29 itself used in the micropump of the present invention is a known member described in Patent Document 3. For example, the electrodes can be installed by packing around the porous membrane. The porous membrane can be supported by a support. The porous membrane is, for example, a nickel metal filter or a polycarbonate filter. Polycarbonate filters are also commercially available as Sansho Kashima Co., Ltd. as a membrane filter. This membrane is made of polycarbonate film and is a track-etched screen filter recommended for any analysis where the sample is observed on the membrane surface. The polycarbonate filter has a pore size of 2 m, 5 m or 12 μm and a thickness of 11 μm. On the other hand, the nickel metal filter has a pore size of 5 μm and a thickness of 1 O / zm. When a voltage of several VDC to several tens of volts (for example, 2V to 15V) is applied between the electrodes before and after the membrane, the liquid flows from the anode side to the cathode side. If the polarity of the applied voltage is reversed, the flow direction of the liquid can be reversed. The flow rate by the porous membrane pumps 0. 02mm ³ Zs~0. Can be varied within the range of 14 mm ³ Zs. The flow rate is roughly proportional to the applied voltage.

[0054] The driving liquid used in the micropump of the present invention can be any liquid that can cause electroosmotic flow. As an example, it is possible to use a liquid in which fine particles having a particle size of 0.01 μm to 0.5 μm having a property of withstanding electricity in a liquid are suspended. Specifically, a colloidal solution (for example, a polystyrene colloid solution or a silica colloid solution) in which fine particles are separated in a solution can be used as a driving liquid. Also, no electrolysis will occur.

Electrolyte solution that is treated like V, pure water or purified water can also be used.

[0055] The method of using the micropump 20 to 20D of the present invention is as follows. First, the target sample solution is injected into port 7 of microfluidic chip 1 (see Fig. 19). Thereafter, the opening of the lower space 33 of the outer shell 23 (or 23A, 23B, 23C, 23D) of the micropump 20 (or 20A, 20B, 20C, 20D, 20E) of the present invention is aligned with the opening of the port 7. Then, the micro pump 20 is placed on the PDMS substrate 3. Since the outer shell 23 is formed of PDMS, the microphone pump 20 can self-adsorb with the PDMS substrate 3. Next, the driving liquid is filled in the upper space 31 of the outer shell 23. The driving fluid flows from the first hole 37 (or the driving fluid inlet 59) into the lower space 33 through the second hole 39 through the bypass channel (first groove) 41 (or 41A to 41D). The air in the lower space 33 is released from the third hole 45 through the air vent channel (second groove) 49 (or 49A to 49D) to the atmosphere through the fourth hole 47 (or air outlet 57). as a result In addition, the lower space 33 can be filled with the driving liquid simultaneously with filling the upper space 31 with the driving liquid. When filling the driving fluid from the upper space 31 to the lower space 33, pressure can be applied to the upper space as necessary. Further, the first hole 37 and the fourth hole 47 or the air outlet 57 can be sealed as necessary. When the upper space 31 and the lower space 33 are filled with the driving liquid, when a predetermined DC voltage is applied to the electrodes 25 and 27, the driving liquid in the upper space 31 permeates into the lower space 33 through the porous film 29. The sample solution in the port 7 is fed into the microchannel 5 by the pressure of the electroosmotic flow at that time. It is preferable that the driving solution and the sample solution do not mix and form a clear interface.

In the case of the micropump 20E of the present invention, when a predetermined DC voltage is applied to the electrodes 25 and 27, the driving liquid in the upper space 31 permeates into the lower space 33 through the porous film 29. Since the diaphragm 61 swells to the port 7 side and the volume of the port 7 decreases, the driving force of the driving liquid is transmitted to the sample solution through the diaphragm 61. Since the driving solution and the sample solution are separated by the diaphragm 61, the micro pump 20E is useful when the sample solution and the driving solution are mixed with each other. Needless to say, the micropump having the diaphragm 61 can be used even when the driving solution and the sample solution do not mix and form a clear interface.

[0057] Bypass flow path (first groove) 41 (or 41A) and air vent flow path (second groove) 49 (or 49 A, 49B, 49C) pressure loss is fine flow path 5 (see Fig. 10) If it is larger, the driving liquid in the lower space 33 does not flow backward from the bypass flow path 41 or the air vent flow path 49 to the upper space 31 even if the electroosmotic flow is caused. However, if the inner diameter of the bypass channel 41 or the air vent channel 49 is increased in order to facilitate the flow of the driving fluid or bubbles, backflow may occur. Inlet 59) and hole 47 (or air outlet 57) need to be sealed.

FIG. 11 is a partial schematic cross-sectional view of still another embodiment of the micropump of the present invention. In this embodiment, the bypass flow path (first groove) 41 (or 41A) and air vent flow path (second groove) 49 (or 49A, 49B, 49C) shown in FIGS. Instead, driving liquid supply pipes 63 and 65 and air vent pipes 67 and 69 are arranged on the outer shell 23E. The driving fluid supply pipes 63 and 65 are connected to the driving fluid source via on-off valves VI and V2, respectively. Also The air vent pipes 67 and 69 open to the driving liquid recovery container 71 via the on-off valves V3 and V4, respectively. A lid 73 covering the upper space 31 is placed on the upper end surface of the outer shell 23E. The lid 73 can be used without the force used to prevent the driving fluid in the upper space 31 from being contaminated by dust, microorganisms, carbon dioxide, etc. in the atmosphere. Electrodes 25 and 27 are connected to a DC power source 64 via a switching switch 62. The DC power source 64 may be a power source device that obtains a DC power source through a converter in addition to a primary battery or a secondary battery. Further, voltage adjusting means such as a variable resistor can be provided. In the case of the micropump shown in FIG. 11, the outer shell 23E may be made of synthetic resin or metal in addition to PDMS.

As shown in FIG. 11, the micropump 20 F is placed on the upper opening of the port 75 of the microchip 73. Like the conventional microchip 1, the microchip 73 includes an upper surface substrate 77 and a lower surface substrate 79, and the upper surface substrate 77 has a microchannel 81 for feeding a material solution. Microchannel 81 communicates with port 75! /

As shown in FIG. 12, the microchip 73 is characterized in that the upper substrate 77 further has two flow paths communicating with the port 75 in addition to the microchannel 81. One is a supply line 83 for supplying a sample solution to the port 75, and the other is an air vent line 85. As shown in the figure, the replenishment line 83 is open near the bottom of the port 7 and the air vent line 85 is open at the top of the port 7. That is, since the air vent pipe 85 is constituted by a groove formed on the upper surface of the upper surface board 77, it is sealed by the joint 87 attached so as to cover it.

The operation of the micropump 20F mounted on the microchip 73 as shown in FIG. 11 will be described with reference to FIGS. 13 and 14. The supply line 83 communicates with a sample solution tank 93 with a hand pump 91 via a supply pipe 89 having an on-off valve V5. The air vent line 85 opens to the sample solution recovery container 97 via an air vent pipe 95 having an on-off valve V6. For example, the air vent pipe 95 may be formed of a transparent member such as glass at the vertical portion so that the rise in the liquid level can be visually observed. Since the above-described on-off valves V1 to V6 affect the operation of the microphone pump, it is preferable to use a precise structure that does not leak when closed. In addition, the microchannel 81 has start-up work and Open / close valve to prevent the replenished sample solution from flowing downstream during replenishment work

V7 is provided.

[0062] When starting in a state in which neither the upper space 31 nor the lower space 33 of the pump main body 20F is filled with the driving liquid and the sample solution is filled in the port 75, First, the open / close valves VI and V2 and the sample solution tank 93 are also closed by the open / close valve V8 and the open / close valve V7 leading to the microchannel 81, and the open / close valves V4, V5 and V6 are opened. To feed the sample solution to port 75. When the sample solution comes out from the front end side of the air vent line 95, the air in the port 75 is pushed out, so the on-off valve V6 is closed. The sample solution accumulates in the port 75, and the diaphragm 61 is pushed upward, for example, as shown by the broken line in FIG. In this figure, the deformation of the diaphragm 61 is exaggeratedly drawn. When a sufficient amount of sample solution has accumulated in the port 75, the liquid supply from the sample solution tank 93 is stopped and the on-off valve V5 is closed.

Next, the on-off valves VI and V2 communicating with the driving fluid tank 99 and the on-off valves V3 and V4 for venting air are opened, and the driving fluid is supplied to the upper space 31 and the lower space 33 of the micropump 20F. On-off valve V3, V4 force When the driving fluid comes out, the air venting is finished, so the on-off valves V1 to V4 are closed and the operation preparation of the micro pump 20F is completed. In order to sufficiently vent the air in the vicinity of the porous thin film 29 and the electrodes 25 and 27, it is preferable to perform the above-described driving liquid supply operation again after preparing the micro pump for a while.

[0064] In the above, the sample solution is filled before the filling of the driving liquid. When the driving liquid is supplied with the on-off valve V4 opened, the diaphragm 61 swells downward due to the weight of the driving liquid. This is because the sample solution cannot be supplied sufficiently. However, if the sample solution is supplied with the on-off valve V2 set to “low” and V4 set to “open” after that, the supply of the driving fluid to the lower space 30 is stopped at a predetermined amount. This is possible because the driving fluid is pushed out from the on-off valve V4. Any method can be used as long as the upper space 31, the lower space 33, and the port 75 are filled with liquid in a state where air is removed.

[0065] In this way, with the respective liquids supplied to the upper space 31, the lower space 33 and the port 75, only the on-off valves VI and V7 are opened, and a predetermined voltage is applied between the electrodes 25 and 27. Then, operate the microphone pump. Open / close valve VI is set to “open” to keep the driving fluid head h constant. It is for maintaining. As a result, the fine particles in the driving liquid pass through the porous film 29, and accordingly, the driving liquid flows from the upper space 31 to the lower space 33 minutely. As a result, the diaphragm 61 swells downward, the volume of the lower space 33 increases, the volume of the port 75 decreases, and the sample solution is sent out from the port 75 to the microchannel 81. Since the diaphragm 61 is incompressible, the flow rate of the driving solution and the flow rate of the sample solution always match.

[0066] With the operation of the micropump 20F, the volume of the lower space 33 increases, and eventually the diaphragm 61 approaches the original shape shown by the solid line in FIG. 14, so the operation is stopped at a predetermined timing, and the sample solution Perform replenishment work. This is because the on-off valve V5 of the supply pipe 89 and the air vent Z of the lower space 33 are opened, and the other on-off valve is closed and the hand pump Just activate 91. As a result, the sample solution pumped to the port 75 pushes up the diaphragm 61 and pushes the driving liquid in the lower space 30 to the driving liquid collection container 71 through the air vent Z driving liquid discharge pipe 69 and the open / close valve V4. When the predetermined amount is supplied, the on-off valves V4 and V5 are closed, the on-off valve V7 is opened, and the operation of the micropump 20F is resumed.

FIG. 15 is a schematic diagram showing another embodiment of a microchip on which the micropump of the present invention is mounted. The port 75 is enlarged so as to penetrate the bottom substrate 81 of the microchip 73. Specifically, a through hole is provided in the lower surface substrate 81, and a cup-shaped container 101 is disposed below the through hole. The inside of the container 101 is an enlarged port 75. The size and shape of the diaphragm 61 are appropriately selected according to the depth of the expansion port 75. In this way, by increasing the depth of the expansion port 75, the operable period can be extended by one sample solution replenishment.

FIG. 16 is a schematic diagram showing still another embodiment of a microchip on which the micropump of the present invention is mounted. In the above embodiment, the sample solution is manually replenished with the hand pump 91. In the embodiment of FIG. 16, the replenishment pump 103 that operates with a predetermined actuator is used. Further, in this embodiment, there is provided a control device 105 that controls the operation of the replenishment pump 103 and the on-off valves V1 to V7 and the open / close operation as necessary, and performs the replenishment operation at a predetermined timing. The timing of the replenishment operation is as follows: (A) Measuring the operation time of the micro pump, (B) Measuring the total flow rate with a flow meter, etc. For example, a method of measuring with a sensor can be considered. Such a configuration makes it possible to operate a microphone port pump that has been automated for a long time.

FIG. 17 is a schematic cross-sectional view of still another embodiment of the micropump of the present invention. This micropump 20G is configured vertically symmetrically. That is, the porous membrane 27 and the pair of electrodes 25 and 27 are arranged so as to divide the inside of the outer shell 23F into two equal parts. In this case, it is not necessary to incline the porous membrane or the electrode, and it may be attached in a horizontal state. This is because there is no need to vent the air. A diaphragm 61a is fixed to the upper end of the upper space 31 of the outer shell 23F divided into two equal parts by the porous film 27, and a diaphragm 61b is fixed to the lower end of the lower space 33, respectively. A driving liquid 223 is hermetically filled in the closed upper space 31 defined by the diaphragm 61a and the porous film 27. Similarly, the driving liquid 223 is hermetically filled in the closed lower space 33 defined by the diaphragm 61b and the porous film 27. What is important here is that the amount of driving fluid in one closed space is larger than the amount of driving fluid in the other closed space. For example, as shown in the drawing, there is a driving liquid in the closed upper space 31 as the diaphragm 61a bulges outward from the outer shell 23F, whereas in the closed lower space 33, the diaphragm 61a There is only the amount of driving fluid that 61b sinks inward of the outer shell 23F. It is easy to make a difference in the amount of drive fluid in each space. Since the inner volume of the outer shell 23F is known, an amount of driving fluid corresponding to the bisected amount is injected into the closed upper space 31 and the closed lower space 33 by a known and conventional means such as a syringe. Thereafter, a voltage is applied to the electrode to generate an electroosmotic flow, and the driving liquid in one space is moved into the other space. The amount of driving fluid in the destination space increases, and conversely, the amount of driving fluid in the source space decreases. In other words, the pressure in the movement destination space increases, so that the diaphragm bulges, while the pressure in the movement source space decreases, so that the diaphragm is recessed. Therefore, in the micropump 20G in this embodiment, the driving liquid is always kept in a sealed state in the pump, and the driving liquid is not put in and out, replaced or replenished except in special cases.

[0070] A method of using the micropump 20G will be described with reference to FIGS. 18A to 18C. The sealed micropump 20G shown in Fig. 17 is placed in alignment with the upper opening of the port 75 of the microchip 73. The microchip itself is not limited to the illustrated embodiment, and any microchip having a port and a microchannel can be used. For example, in Figure 19 Of course, the microchip 1 can be used. When placed in the upper part of the opening of the port 75, the direction of the amount of driving fluid in the upper space 31 must be greater than the amount of driving fluid in the lower space 33. This can be easily confirmed by looking at the appearance of the diaphragm. In other words, the bulging side should be on the top and the concave side should be on the bottom. In the case of the macro chip 73 shown in FIG. 18A, the sample solution 225 is injected into the port 75 after the micropump 20G is arranged. Since the method for injecting the sample solution into the port 75 has already been described in detail, it will be omitted here. In the case of a microchip that does not have a mechanism such as the supply line 83, a sample solution is injected into the port in advance, and then the micropump 20G is disposed. Connect the upper electrode 25 side to the positive side of the DC power supply and the lower electrode 27 to the negative side, and apply a predetermined voltage.

By applying voltage, an electroosmotic flow is generated through the porous membrane 29, and the driving liquid 223 in the upper space 31 moves toward the lower space 33 by force. With this movement, the diaphragm 61b in the lower space 33 swells downward, the volume of the lower space 33 increases, the volume of the port 75 decreases, and the sample solution 225 is sent from the port 75 to the microchannel 81. Since the 6 lb diaphragm is incompressible, the flow rate of the driving fluid and the sample solution always match. As shown in FIG. 18B, the application of voltage is stopped when the downward bulge of the diaphragm 61b in the lower space 33 reaches the limit.

[0072] After that, the micropump 20G is removed from the microchip 73, and the micropump 20G is turned upside down (that is, turned over) so as to be aligned with the upper opening of the port 75 of the microchip 73 and disposed again. FIG. 18C shows a state in which the micropump 20G is turned over and aligned with the upper opening of the port 75 of the microphone mouth chip 73 and rearranged. The former lower space 33 is now located on the upper side, and the upper space 31 is located on the lower side. In this case, since the electrode is also turned upside down, when applying a voltage, the electrode 27 must be connected to the positive side and the electrode 25 must be connected to the negative side. Thus, when a voltage is applied between the electrodes, an electroosmotic flow is generated again, and the driving liquid 223 flows from the upper side to the lower side, so that the sample solution 225 in the port 75 can be sent to the microchannel 81. Therefore, the sample solution delivery work can be efficiently performed by repeating the operations shown in FIGS. 18A to 18C. [0073] By using the micropump 20G shown in FIG. 17, not only the complicated driving liquid supply operation as shown in FIGS. 11 to 16 can be omitted, but the driving liquid is dust and microbes in the atmosphere. It is completely prevented from being contaminated or altered by carbon dioxide gas. Since there is no need to put in and out the drive fluid, or to replace or replenish it, not only can the cost of the drive fluid be saved, but the overall configuration of the device is simplified, resulting in lower device costs.

[0074] As described above, specific embodiments of the micropump of the present invention have been described with reference to the drawings. The micropump of the present invention is not limited to the illustrated embodiments, and various modifications are possible. Can be applied. For example, in the illustrated embodiment, the first shielding sheet and the second shielding sheet are described as separate sheets, but the first shielding sheet and the second shielding sheet are one continuous sheet. It can also be.

[0075] When forming the first groove and the second groove, an aspect of being arranged on the outer wall surface of the outer shell, an aspect of being arranged on the shielding sheet, and an aspect of being arranged in the wall of Z or the outer shell as appropriate You can combine them conveniently. For example, the first groove is disposed on the outer wall surface of the outer shell, the second groove is disposed on the shielding sheet, and conversely, the first groove is disposed on the shielding sheet, and the second groove is disposed. It is possible to adopt a mode in which the outer shell is disposed on the outer wall surface.

[0076] The groove shape can also be a combination of a linear shape and a meandering shape. For example,

Both the first groove and the second groove can be straight grooves or serpentine grooves, or one can be a straight groove and the other can be a serpentine groove.

[0077] The size of the micropump itself is not an essential requirement of the present invention! /. An appropriate size can be selected according to the application. Depending on the specific size of the micropump, the size of the sheet, hole and groove can be adjusted and changed appropriately to the optimum values.

[0078] The shape of the outer shell 23 is not limited to a cylindrical shape, and may be a prismatic shape. Further, the material of the outer shell 23 is not limited to PDMS, and can be glass, synthetic resin, or metal that can self-adhere with the PDMS substrate 3.

[0079] When saline is used as the driving liquid used in the micropump of the present invention, electrolysis occurs after voltage application, and bubbles are generated and the flow rate is decreased with time. In the colloidal polystyrene solution and the colloidal silica solution, such bubbles are not generated and the flow rate is not reduced over time, and the flow rate is constant. Example 1

(1) A microfluidic chip 1 having a cross-sectional structure as shown in FIG. 19 was produced. The facing substrate 10 was made of glass with a thickness of 1 mm, and the substrate 3 was made of PDMS with a thickness of 2 mm. The width and height of microchannel 5 were 200 m each, and the length (distance) was 50 mm. The inner diameter of port 9 was lmm. The inner diameter of port 7 was 9 mm.

(2) A micropump 20A shown in FIG. 4 was produced. Micro pump 20A PDMS outer shell 23A outer diameter is 20mm, height is 18mm, upper space 31 inner diameter is 13mm, lower space 33 inner diameter is 10mm, flange 35 outer diameter is 30mm, height Was 2 mm. A first hole 37 (inner diameter lmm) was drilled at a position 5 mm from the upper end of the outer shell 23A, and a second hole 39 (inner diameter lmm) was drilled at a position 6 mm from the lower surface of the flange portion 35. Similarly, a fourth hole 47 (inner diameter lmm) is drilled at a position 2 mm from the upper end of the outer shell 23A, and a third hole 45 (inner diameter 2 mm) is formed at a position 7.9 mm from the bottom surface of the flange portion 35. Drilled. As the porous membrane 29, a polycarbonate porous membrane having a pore diameter of 2 μm, the number of pores of 1.500000, and a thickness of 11 m was used. Electrodes 25 and 27 were connected to the upper surface side and lower surface side of this porous membrane via packing, respectively. The outer diameter of the electrode-equipped porous membrane 29 was 13 mm. An electrode-equipped porous membrane 29 was attached in an inclined manner in the hollow portion of the outer shell 23A. Next, concave portions 53 and 55 (inner diameter of 100 m, concave portion interval of 7 mm) and first groove 41A (width 100 / zm, depth 100 / zm, length 8.lm m) are formed! The first shielding sheet 43A made of PDMS was self-adsorbed on the outer wall surface of the outer shell 23A in alignment with the first hole 37 and the second hole 39. Similarly, recessed portions 53 and 55 (inner diameter 100 / ζ πι, recessed portion interval 7 mm) and second groove 49 mm (width 1000 / ζ πι, depth 100 m, length 8. lmm) are formed. The second shielding sheet 51A made of PDMS was self-adsorbed on the outer wall surface of the outer shell 23A in alignment with the third hole 45 and the fourth hole 47.

(3) Port 7 of the microfluidic chip 1 was filled with an oily sample liquid colored in red. Thereafter, the opening of the lower space 33 of the micropump 20A was aligned with the upper surface of the opening of the port 7, and the micropump 20A was self-adsorbed to the PDMS substrate 3.

(4) Colloidal solution in which silica particles (particle size: 0.09 m) are dispersed at a concentration of 1% in ion exchange water (distilled water from which ions have been removed) in the hollow upper space 31 of the micropump 20A. Was filled as a driving fluid. The same colloidal solution was injected from the first hole 37 with a syringe. It was confirmed that the colloidal solution flows from the first hole 37 through the first groove 41A into the hollow lower space 33 through the second hole 39. The time required for the hollow space 33 to be filled with the colloidal solution was 10 seconds.

(5) When the lower space 33 is filled with the colloidal solution, the fourth hole 47 is sealed. When a DC voltage of 15 V is applied to the positive electrode 25 and the negative electrode 27, an electroosmotic flow from the hollow upper space 31 to the hollow lower space 33 is generated, and accordingly, the oily colored liquid in the port 7 is fine. It was confirmed that the liquid was fed to port 9 through channel 5. A clear interface existed between the driving liquid and the oily coloring liquid.

Example 2

[0081] The micropump 20A in Example 1 was separated from the microfluidic chip force of Example 1 and self-adsorbed on the upper surface of the port 7 of another microfluidic chip having the same flow path structure, and the same silica as in Example 1 When a liquid feeding experiment was performed using a colloidal solution, the same result as in Example 1 was obtained. In addition, liquid leakage from the adhesive interface between the micropump 20A and the PDMS substrate 3 did not occur. From this, it can be understood that the micropump according to the present invention can be effectively used repeatedly as an external micropump in a microfluidic chip. Example 3

A micropump 20E shown in FIG. 10 was produced by the same method as described in Example 1. For the diaphragm 61, a 0.3 mm thick polypropylene dome-shaped film was used. This film was fixed to the inner wall surface at the lower end of the lower space with a synthetic resin ring. Port 7 of the microfluidic chip 1 was filled with physiological saline colored red. Thereafter, the micropump 20E was placed on the upper surface of the opening of the port 7. At this time, the diaphragm 61 was deformed so as to enter the lower space 33. In the same manner as in Example 1, the same driving fluid as that used in Example 1 was filled in the upper space and lower space of the micro pump 20E, and a DC voltage of 15 V was applied to the positive electrode 25 and the negative electrode 27. However, an electroosmotic flow from the hollow upper space 31 to the hollow lower space 33 is generated, and accordingly, the diaphragm 61 gradually swells downward, and accordingly the colored physiological saline in the port 7 flows into the fine flow path. It was confirmed that the liquid was fed to port 9 via 5.

Industrial applicability [0083] The micropump of the present invention is used to collect and isolate various cells and to clone specific cells in the immunological field, hematology field, medical field, genetic engineering field, applied life science field, and the like. Effective use in microfluidic chips used for purposes such as proliferation, sorting of cells expressing specific antigens on the cell surface, body membrane cell body analysis, cell chromosome analysis, and urinary formation classification can do.

Brief Description of Drawings

FIG. 1 is a partial schematic cross-sectional view of an example of an embodiment of a micropump according to the present invention.

2 is a partial schematic plan view showing an example of the shape of the first groove formed on the outer wall surface of the outer shell of the micropump in FIG. 1. FIG.

FIG. 3 is a schematic plan view of another embodiment of the first shielding sheet or the second shielding sheet.

4 is a partial schematic cross-sectional view of another embodiment of the micropump of the present invention using the shielding sheet shown in FIG.

5 is a partial schematic perspective view of the micropump shown in FIG.

FIG. 6 is a schematic plan view of still another embodiment of the second shielding sheet.

7 is a partial schematic cross-sectional view of another embodiment of the micropump of the present invention using the shielding sheet shown in FIG.

FIG. 8 is a partial schematic cross-sectional view of another embodiment of a micropump according to the present invention.

FIG. 9 is a partial schematic cross-sectional view of still another embodiment of the micropump according to the present invention.

FIG. 10 is a partial schematic cross-sectional view of still another embodiment of the micropump according to the present invention.

FIG. 11 shows a configuration of an example of an embodiment of a micropump device in which a micropump according to the present invention is mounted on a microfluidic chip, where (a) is a longitudinal sectional view and (b) is a plan view.

FIG. 12 is a partial cross-sectional view showing the main part of the micropump in FIG. 11, where (a) is a view from the a arrow in FIG. 11 (b) and (b) is a view from the b arrow in FIG. is there.

13 is a schematic diagram showing a pump system using the micropump device of FIG.

FIG. 14 is a view schematically showing a liquid flow in a pump system using the micropump device of FIG. 11.

FIG. 15 is a schematic diagram showing a micropump device and a pump system according to another embodiment of the present invention. FIG. 16 is a schematic view showing a micropump device and a pump system according to still another embodiment of the present invention.

FIG. 17 is a partial schematic cross-sectional view of another embodiment of a micropump according to the present invention.

FIG. 18A is a partial schematic cross-sectional view for explaining the operation of the micropump of FIG.

FIG. 18B is a partial schematic cross-sectional view illustrating the operation of the micropump of FIG.

18C is a partial schematic cross-sectional view illustrating the operation of the micropump in FIG.

FIG. 19 is a partial schematic cross-sectional view of an example of a conventional micropump shown in Patent Document 3.

20 is an exploded perspective view of the positive electrode 205 and the negative electrode 207 shown in FIG. 19 and the porous membrane 209 interposed between the electrodes.

FIG. 21 is a partial schematic sectional view showing an example of use of the conventional micropump 200 shown in FIG.

Explanation of symbols

1 Microfluidic chip

3 PDMS substrate

5 Fine channel

7 ports

9 port

10 facing board

20, 20A-20G Micro pump of the present invention

23, 23A-23E Outer shell

25 Upper electrode

27 Bottom electrode

29 Porous membrane

31 Upper space

33 Lower space

35 Flange

37 1st hole

39 Second hole , 41A 41C 1st groove, 43A, 43B 1st shield sea- 卜 3rd hole

4th hole

, 49A 49C Second groove

, 51A 51B 2nd shielding sea small, 55 concave

Air outlet

Liquid inlet

, 61a, 61b diaphragm

Diaphragm holder

Sample solution supply path

Air vent

Sample solution supply tube

Sample solution tank

Control device

-V7 On-off valve

Release valve

Conventional micropump plus electrode

Negative electrode

Porous membrane

Liquid storage space

Liquid feeding tube

Lower space

Porous membrane support

Aperture

Aperture 223 Driving liquid 225 Sample liquid

Claims

The scope of the claims

[1] An outer shell having a through-hole, and a porous membrane disposed inside the hollow so as to divide the hollow into two vertically, and interposed between a plus electrode and a minus electrode, In the micro-flow micropump using the electroosmotic flow effect passing through the porous membrane, a liquid-filling bypass channel communicating with the lower space of the hollow portion divided by the porous membrane is disposed. A micropump characterized by having an air vent channel communicating with the atmosphere from the lower space!

[2] Height force of bottom surface force of the lower space at the inlet of the air vent channel opened inside the lower space Bottom force of the lower space at the outlet of the bypass channel opened inside the lower space The micropump according to claim 1, wherein the micropump is at least a height of

[3] The bypass flow path is formed outside the outer shell or in the wall of the outer shell, and the air vent flow path is formed outside the outer shell or in the wall of the outer shell. The micropump according to claim 1 or 2, wherein

[4] The bypass channel formed outside the outer shell has a second hole serving as a bypass channel outlet disposed through the lower space of the outer shell, and a lower end of the bypass channel. A first groove that communicates with the second hole, and a first shielding sheet that shields the second hole and the first groove. The first groove is formed outside the outer shell. It is formed either on the wall surface or on the bonding surface side of the first shielding sheet, and the upper end of the first groove is disposed so as to penetrate through the upper space of the outer shell, and Communicates with the first hole shielded by one shielding sheet, or communicates with the atmosphere at the upper end of the first shielding sheet,

The air vent channel formed outside the outer shell has a third hole serving as an air vent channel inlet penetrating the lower space of the outer shell, and a lower end of the third hole. A second groove that communicates with the second hole and a second shielding sheet that shields the third hole and the second groove, and the second groove is formed on the outer wall surface of the outer shell. Or the upper end of the second groove is disposed so as to penetrate through the upper space of the outer shell, and the second shielding sheet is attached to the second shielding sheet. Communicating with the fourth hole shielded by the shielding sheet, or communicating with the atmosphere at the upper end of the second shielding sheet, The height of the third hole from the bottom surface of the lower space is equal to or higher than the height of the second hole from the bottom surface of the lower space,

[5] The bypass channel formed in the outer shell wall includes a second hole serving as a bypass channel outlet disposed in a lower space of the outer shell and a first groove. The lower end of the first groove communicates with the second hole, and the upper end of the first groove communicates with the atmosphere on the upper end surface of the outer shell, or It opens to the inner side of the upper space of the outer shell or communicates with the first hole that opens toward the outer side of the outer shell,

The first groove communicates with the first hole opening toward the inside of the upper space of the outer shell, and the second groove opens to the inside of the upper space of the outer shell. 4. The micropump according to claim 3, wherein when communicating with the hole, the position of the first hole from the bottom surface of the lower space is lower than the position of the fourth hole of the bottom space bottom force.

[6] The inner diameter of the inlet (third hole) of the air vent channel opened inside the lower space is the inner diameter of the outlet (second hole) of the bypass channel opened inside the lower space. The micropump according to claim 1, wherein the micropump is larger than the micropump.

[7] The shape of each of the first groove and the second groove is any one selected from the group consisting of a linear shape and a meandering shape. Micro pump.

[8] The outer shell is formed of polydimethylsiloxane (PDMS) or glass force, and the first shielding sheet and the second shielding sheet are formed of PDMS. The micropump according to any one of claims 1 to 7.

9. The micropump according to any one of claims 1 to 8, further comprising a diaphragm that closes the lower space in the vicinity of an end of the lower space of the outer shell.

[10] An outer shell having a penetrating hollow portion, and a porous membrane interposed between the plus electrode and the minus electrode, arranged inside the hollow portion so as to divide the hollow portion into two vertically In the micropump for micro flow rate utilizing the electroosmotic flow effect passing through the porous membrane, a diaphragm for sealing the upper space in the vicinity of the end of the upper space of the hollow portion divided into two by the porous membrane And having a diaphragm for sealing the lower space in the vicinity of the end of the lower space of the hollow portion divided into two by the porous membrane, and each of the sealed upper space and lower space has a predetermined amount. A micropump characterized by being filled with a driving fluid.

[11] One or more ports opened to the atmosphere, a polydimethylsiloxane substrate having a fine channel communicating with the port, and a facing surface bonded to a surface of the polydimethylsiloxane substrate formed with a fine channel In a microfluidic chip comprising a substrate,

A microfluidic chip, wherein the micropump according to any one of claims 1 to 10 is detachably mounted on an opening upper surface of at least one of the ports.

[12] A substrate on which the opening port is formed is further formed with a sample solution supply path for supplying a sample solution in the opening port and an air vent path for extracting air in the opening port. 12. The microfluidic chip according to claim 11, wherein:

[13] The sample solution replenishment path is provided with an on-off valve and a replenishment pump for feeding the sample solution from the sample solution tank into the port, and when the sample solution is replenished, the on-off valve, the replenishment pump, 13. The microfluidic chip according to claim 12, further comprising a control device for operating.