JP3842677B2 - Electroosmotic pump - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electroosmotic flow pump for feeding a minute amount of solution using electroosmotic flow.
[0002]
[Prior art]
Capillary electrophoresis devices and HPLC systems that are used for microseparation analysis of ecological substances such as proteins, peptides, and nucleic acids use electroosmotic flow pumps that send a small amount of liquid using electroosmotic flow. Yes.
[0003]
FIGS. 1A and 1B show the configuration of a conventional electroosmotic pump, respectively. The conventional electroosmotic flow pump of FIG. 1A includes a liquid feeding tank 101 in which a solution is placed, a first electrode 102 immersed in the solution in the liquid feeding tank 101, and one end of the liquid feeding tank 101. A capillary tube 103 that is immersed in the solution and the other end forms a projecting port, a second electrode 104 mounted on the inner peripheral portion in the vicinity of the other end of the capillary tube 103, and the capillary tube 103. A DC power supply device 105 that applies a predetermined DC high voltage between the first electrode and the second electrode so as to generate an electroosmotic flow in a direction from the liquid tank 101 side toward the other end side of the capillary tube 103. And.
[0004]
In addition, the conventional electroosmotic flow pump of FIG. 1 (B) was immersed in the first and second liquid feeding tanks 106 and 107 into which the solution was put, respectively, and the solution in the first liquid feeding tank 106. The first electrode 108, the second electrode 109 immersed in the solution in the second liquid feeding tank 107, and both ends are immersed in the first and second liquid feeding tanks 108 and 109, respectively. A capillary tube 111 with a branching portion having a branching portion 110 formed of a three-way joint and a DC power supply device 112 that applies a predetermined DC high voltage between the first electrode 108 and the second electrode 109 are provided.
[0005]
[Problems to be solved by the invention]
The conventional electroosmotic pumps of FIGS. 1 (A) and 1 (B) can send a minute amount of solution, but send a mixture of two solutions with a continuous composition change. There is a problem that (gradient feeding) is not possible.
[0006]
An object of the present invention is to provide an electroosmotic pump capable of supplying a gradient.
[0007]
Another object of the present invention is to provide an electroosmotic flow pump which can continuously change the composition of a mixed solution with a simple configuration.
[0008]
[Means for Solving the Problems]
The electroosmotic flow pump of the present invention includes a first liquid feeding tank containing a first solution, a first electrode immersed in the first solution in the first liquid feeding tank, and a second electrode. A second liquid feeding tank containing the solution, a second electrode immersed in the second solution in the second liquid feeding tank, a liquid feeding path, and a power supply device. The liquid feeding path includes first to third tube portions whose one ends are connected so as to be able to communicate with each other, and a third electrode is disposed at the inner center portion of the first to third tube portions. A joint tube, a first capillary tube having one end immersed in the first solution in the first liquid feeding tank and the other end connected to the other end of the first tube portion of the three-way joint tube; Is composed of a second capillary tube which is immersed in the second solution in the second liquid feeding tank and the other end of which is connected to the other end of the second tube portion of the three-way joint tube. As a power supply device, between the first electrode and the third electrode and between the second electrode and the third electrode, the electroosmotic flow in the direction toward the three-way joint tube is generated in the first and second capillary tubes. A direct current power supply device for applying a predetermined direct current high voltage between the electrodes is used. And the electroosmotic flow pump of this invention discharges the mixed solution which mixed the 1st solution and the 2nd solution from the other end of the 3rd pipe part of a three-way joint pipe. According to the electroosmotic pump of the present invention, the DC high voltage applied between the first electrode and the third electrode and between the second electrode and the third electrode is arbitrarily adjusted. In addition, a minute amount of a mixed solution in which the mixing ratio of the first solution and the second solution is continuously changed can be fed (that is, gradient feeding becomes possible).
[0009]
Therefore, as a DC power supply device, a DC high voltage is applied between a first DC power supply that applies a DC high voltage between the first electrode and the third electrode, and between the second electrode and the third electrode. It is preferable to use a second DC power source that applies a voltage, and the first DC power source and the second DC power source can be separately voltage-adjusted.
[0010]
The capillary tube used, it is possible to use fused silica capillaries with a fixed positive charge or negative charge relief Le to the inner wall portion.
[0011]
The gradient liquid feeding can also be obtained by using another electroosmotic flow pump of the present invention. Another electroosmotic pump according to the present invention includes a first pump unit, a second pump unit, and a connected output line.
[0012]
The first pump unit includes first and second liquid feeding tanks each containing a first solution, a first electrode immersed in the first solution in the first liquid feeding tank, A second electrode immersed in the first solution in the second liquid feeding tank, a first capillary tube having one end immersed in the first solution in the first liquid feeding tank, and one end Includes a second capillary tube immersed in the first solution in the second liquid-feeding tank, and first to third tube portions whose one ends are connected so as to communicate with each other. The other end of each of the second capillary tubes includes a first three-way joint tube connected to the first and second tube portions. In addition , gels holding charges having different polarities are fixed inside the first and second capillary tubes by chemical bonds, and the first three-way joint is also provided inside the first and second capillary tubes. A first direct current power source for applying a predetermined direct current high voltage is provided between the first electrode and the second electrode so as to generate an electroosmotic flow in a direction toward the tube. Similarly, the second pump unit includes third and fourth liquid feeding tanks each containing a second solution, and a third liquid immersed in the second solution in the third liquid feeding tank. Electrode, a fourth electrode immersed in the second solution in the fourth liquid feeding tank, and a third capillary having one end immersed in the second solution in the third liquid feeding tank A tube, a fourth capillary tube having one end immersed in the second solution in the fourth liquid-feeding tank, and first to third tube portions connected to each other so as to communicate with each other. In addition, each of the third and fourth capillary tubes has a second three-way joint tube connected to the first and second tube portions at the other end. In addition , gels holding charges having different polarities are fixed inside the third and fourth capillary tubes by chemical bonds, and a second three-way joint is placed inside the third and fourth capillary tubes. A second direct current power source for applying a predetermined direct current high voltage is provided between the third electrode and the fourth electrode so as to generate an electroosmotic flow in a direction toward the tube. The connection output pipe is configured to output the combined outputs from the third pipe portions of the first and second three-way joint pipes. Also in this electroosmotic flow pump, by applying a DC high voltage to be applied between the first electrode and the second electrode and between the third electrode and the fourth electrode, the first solution and The gradient solution feeding of the second solution can be easily realized. In this pump as well, it is preferable to use the first DC power supply and the second DC power supply that are separately voltage adjustable.
[0013]
Further, the connection output pipe line includes a third three-way joint pipe having first to third pipe parts that are connected so that one ends thereof can communicate with each other, and a third pipe part of the first three-way joint pipe, A first connecting pipe that connects the first pipe part of the third three-way joint pipe, a third pipe part of the second three-way joint pipe, and a second pipe part of the third three-way joint pipe And a second connecting pipe connecting the two.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 2 is a block diagram showing the configuration of an embodiment of the electroosmotic pump 1 according to the present invention. This electroosmotic flow pump 1 includes a first liquid feeding tank 2 in which a first solution A is placed, and a first electrode 3 immersed in the first solution A in the first liquid feeding tank 2. A second liquid supply tank 4 in which the second solution B is put, a second electrode 5 immersed in the second solution B in the second liquid supply tank 4, and a liquid supply path 6 And a DC power supply device 7. The liquid supply path 6 includes first to third pipe portions 8a to 8c, one end of which is connected so as to be able to communicate with each other, and a tip is disposed at the inner central portion of the first to third pipe portions. A three-way joint tube 8 having three electrodes 9 is provided. The first to third electrodes 3, 5 and 9 are each made of platinum.
[0015]
Further, the liquid feeding path 6 has one end 10 a immersed in the first solution A in the first liquid feeding tank 2 and the other end 10 b connected to the other end of the first pipe portion 8 a of the three-way joint pipe 8. The first capillary tube 10 and one end 11a are immersed in the second solution B in the second liquid feeding tank 4, and the other end 11b is connected to the other end of the second tube portion 8b of the three-way joint tube 8. And a second capillary tube 11 connected thereto. The first and second capillary tubes 10 and 11 are composed of fused silica capillary tubes in which a gel holding a positive or negative charge is fixed inside by a chemical bond. In place of such a capillary tube, a capillary tube filled with silica gel may be used, or an inner wall surface coated with a polymer having a charge may be used. For example, the inner diameters of the first and second capillary tubes 10 and 11 are 75 μm, but the present invention is not limited to this.
[0016]
The DC power supply device 7 is provided between the first electrode 3 and the third electrode 9 so as to generate an electroosmotic flow in the direction toward the three-way joint tube 8 in the first and second capillary tubes 10 and 11. In order to apply a predetermined DC high voltage between the second electrode 5 and the third electrode 9, respectively, first and second DC power supplies HV1 and HV2 are provided. The first DC power supply HV1 and the second DC power supply HV2 can be adjusted separately. Incidentally, the DC voltage to be applied is a high voltage of about 7 kV at the maximum, for example. If the voltage adjustment is finely adjusted by using a computer, the composition of the first and second solutions A and B is continuously changed (with a gradient), and the three-way joint. A minute amount (several hundred nL to several hundred pL / min) of the mixed solution can be fed from the third tube portion 8 c of the tube 8. In this circuit configuration, the first and second DC power supplies HV1 and HV2 are connected so that the third electrode 9 becomes a common electrode. That is, if the first and second electrodes 3 and 5 are positive (+) electrodes, the first and second DC power supplies HV1 and HV2 are connected so that the third electrode 9 becomes a negative (-) electrode. Has been. In this case, the first and second capillary tubes 10 and 11 are each composed of a fused silica capillary tube in which a gel holding a negative charge is fixed inside by a chemical bond. If the first and second electrodes 3 and 5 are negative (−) electrodes, the first and second DC power supplies HV1 and HV2 are connected so that the third electrode 9 becomes a positive (+) electrode. To do. In this case, the first and second capillary tubes 10 and 11 may be constituted by fused silica capillary tubes in which a gel holding a positive charge is fixed by a chemical bond inside.
[0017]
Before starting the liquid feeding, the first and second capillary tubes 10 and 11 are preliminarily filled with an appropriate liquid to be replaced with the first and second solutions A and B. Then, after replacing the liquid to be replaced with the first and second solutions A and B, the gradient liquid feeding is started.
[0018]
FIG. 3 shows a schematic configuration of an electrophoresis apparatus obtained by developing the electroosmotic flow pump according to the embodiment shown in FIG. In this example, a third capillary tube 12 is further provided in the third tube portion 8 c of the three-way joint tube 8, a waste liquid tank 13 is provided at the tip of the third capillary tube 12, and a fourth electrode is disposed in the waste liquid tank 13. 14 is provided. The apparatus also includes a third DC power supply HV3 that applies a DC high voltage between the third electrode 9 and the fourth electrode 14. In this apparatus, electrophoresis is generated in the third capillary tube 12 by applying a voltage from the third DC power source HV3, and the sample molecules are separated in the third capillary tube 12.
[0019]
FIG. 4 is a block diagram showing a schematic configuration of another electroosmotic pump 21 to which the present invention is applied. Another electroosmotic pump according to the present invention includes a first pump unit, a second pump unit, and a connected output line. The first pump unit was immersed in the first and second liquid feeding tanks 22 and 24 in which the first solution A was put, respectively, and the first solution A in the first liquid feeding tank 22. The first electrode 23, the second electrode 25 immersed in the first solution A in the second liquid feeding tank 24, and one end in the first solution A in the first liquid feeding tank 22 Are connected to the first capillary tube 30 immersed in the first capillary tube 30 and one end of the second capillary tube 31 immersed in the first solution A in the second liquid-feeding tank 24 so as to communicate with each other. First and third tube portions 28a to 28c, and the other ends of the first and second capillary tubes 30 and 31 are connected to the first and second tube portions 28a and 28b. 1 three-way joint pipe 28. Inside the first and second capillary tubes 30 and 31, gels containing charges having different polarities are fixed inside by chemical bonds. In this example, a gel having a (−) charge is fixed inside by a chemical bond inside the first capillary tube 30, and a (+) charge is inside the second capillary tube 31. The gel is fixed inside by chemical bonds. Also, an electroosmotic flow in the direction toward the first three-way joint tube 28 is generated inside the first and second capillary tubes 30 and 31 between the first electrode 23 and the second electrode 25. A first DC power supply HV11 for applying a predetermined DC high voltage is provided.
[0020]
Similarly, the second pump unit includes the third and fourth liquid feeding tanks 32 and 34 each containing the second solution B, and the second solution B in the third liquid feeding tank 32. The immersed third electrode 33, the fourth electrode 35 immersed in the second solution in the fourth liquid feeding tank 34, and the second solution in the third liquid feeding tank 32 at one end. The third capillary tube 40 immersed in B, the fourth capillary tube 41 immersed in the second solution B in the fourth liquid feeding tank 34, and one end thereof can communicate with each other. The first to third tube portions 38a to 38c are connected, and the other ends of the third and fourth capillary tubes 40 and 41 are connected to the first and second tube portions 38a and 38b. And a second three-way joint pipe 38. Inside the third and fourth capillary tubes 40 and 41, gels containing charges having different polarities are fixed inside by chemical bonds. In this example, a gel having a (−) charge is fixed inside by a chemical bond inside the third capillary tube 40, and a (+) charge is inside the fourth capillary tube 41. The gel is fixed inside by chemical bonds. The electroosmotic flow in the direction toward the second three-way joint tube 38 is generated inside the third and fourth capillary tubes 40 and 41 between the third electrode 33 and the fourth electrode 35. A second DC power supply HV12 for applying a predetermined DC high voltage is provided.
[0021]
In addition, the connection output pipe line includes a third three-way joint pipe 50 including first to third pipe portions 50a to 50c that are connected so that one ends thereof can communicate with each other, and the first three-way joint pipe 28. A first connecting pipe 51 that connects the third pipe part 28c and the first pipe part 50a of the third three-way joint pipe 50; a third pipe part 38c of the second three-way joint pipe 38; The three-way joint pipe 50 can be configured with a second connecting pipe 52 that connects the second pipe portion 50b. This electroosmotic pump 21 is also applied when a DC high voltage having the polarity shown is applied between the first electrode 23 and the second electrode 25 and between the third electrode 33 and the fourth electrode 35. The gradient solution feeding of the first solution A and the second solution B whose concentration changes according to the direct current high voltage can be easily realized. Even in this pump, the first DC power supply HV11 and the second DC power supply HV12 can be separately voltage-adjusted.
[0022]
As shown in FIG. 4, when the first and third electrodes 23 and 33 are (+) poles and the second and fourth electrodes 25 and 35 are (−) poles, the first and third electrodes The capillary tubes 30 and 40 have a flow path in which (−) charged gel is fixed, and the second and fourth capillary tubes 31 and 41 have a flow in which (+) charged gel is fixed. Use the road. When the polarity of each electrode is reversed, the charge of the fixed gel is also reversed.
[0023]
For the test of the structure shown in FIG. 4, fused silica capillaries having an inner diameter of 75 μm were used as the first and third capillary tubes 30 and 40. Then, in a tube into which allyl groups were introduced in advance by a dynamic coating method, 0.8 mmol of methacrylamide, 0.2 mmol of sodium allyl sulfonate, 0.6 mmol of piperazine diacrylamide was added in 1 mL of 50 mM phosphate buffer. A monomer aqueous solution containing 70 mg of ammonium sulfate was polymerized using an initiator system consisting of ammonium veloxonisulfate and N, N, N ′, N′-tetramethylethylenediamine to obtain a (−) charged gel, 1 capillary tubes 30 and 40 were prepared. Similarly, in the tube, an aqueous monomer solution containing 0.4 mmol piperazine diacrylamide, 0.2 mmol diallyldimethylammonium chloride, 1.0 mmol methacrylamide, and 70 mg ammonium sulfate was polymerized to obtain a (+) charged gel. Thus, second and fourth capillary tubes 31 and 41 were prepared. The first to fourth capillary tubes 30, 31, 40 and 41 are each 6 cm in length, and fused silica in which a detection window is provided in the third tube portion 50 c of the third three-way joint tube 50. Connect the capillary tube attached to the visible ultraviolet spectrometer, remove one end of this capillary tube, introduce 1% thiourea aqueous solution into the first three-way joint tube 28 side by the drop method, reconnect it, and connect between the electrodes. A voltage of 0.5 to 3.0 kV was applied. As a result, it was confirmed that the electroosmotic flow generation efficiency was 10 cm / min per 1 kVlcm.
[0024]
【The invention's effect】
According to the first electroosmotic pump of the present invention, the direct-current high voltage applied between the first electrode and the third electrode and between the second electrode and the third electrode is arbitrarily adjusted. By doing so, there is an advantage that a minute amount of a mixed solution in which the mixing ratio of the first solution and the second solution is continuously changed can be fed with a simple configuration.
[0025]
Moreover, according to the 2nd electroosmotic flow pump of this invention, gradient liquid feeding can be performed with big power by using two pump units.
[0026]
Moreover, according to the structure of this invention, the whole shape of a pump can be reduced in size to the magnitude | size of the case of a cassette tape, or the size below it.
[Brief description of the drawings]
FIGS. 1A and 1B are diagrams showing the configuration of a conventional electroosmotic flow pump, respectively.
FIG. 2 is a block diagram showing a configuration of an embodiment of an electroosmotic pump according to the present invention.
FIG. 3 shows a schematic configuration of an electrophoresis apparatus in which the electroosmotic flow pump according to the embodiment shown in FIG. 2 is developed.
FIG. 4 is a block diagram showing a schematic configuration of another electroosmotic pump to which the present invention is applied.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Electroosmotic flow pump 2 1st liquid feeding tank 3 1st electrode 4 2nd liquid feeding tank 5 2nd electrode 6 Liquid feeding path 7 DC power supply device 8a-8c 1st thru | or 3rd pipe part 8 Three sides Joint tube 9 Third electrode 10 First capillary tube 11 Second capillary tube HV1 First DC power source HV2 Second DC power source

Claims (5)

A first liquid feeding tank containing a first solution;
A first electrode immersed in the first solution in the first liquid feeding tank;
A second liquid-feeding tank containing the second solution;
A second electrode immersed in the second solution in the second liquid feeding tank;
A three-way joint pipe having first to third pipe portions whose one ends are connected to each other so as to communicate with each other, and a third electrode disposed at an inner center portion of the first to third pipe portions;
A first capillary tube having one end immersed in the first solution in the first liquid feeding tank and the other end connected to the other end of the first tube portion of the three-way joint tube;
A second capillary tube having one end immersed in the second solution in the second liquid feeding tank and the other end connected to the other end of the second tube portion of the three-way joint tube;
In order to generate an electroosmotic flow in the direction toward the three-way joint tube in the first and second capillary tubes, between the first electrode and the third electrode and between the second electrode and the second electrode. A DC power supply device that applies a predetermined DC high voltage between each of the three electrodes,
The first and second capillary tubes are fused silica capillaries in which a gel holding a positive or negative charge is fixed to the inner wall part by chemical bonding,
An electroosmotic pump characterized by discharging a mixed solution obtained by mixing the first solution and the second solution from the other end of the third pipe portion of the three-way joint pipe.   The DC power supply device includes a first DC power source that applies a DC high voltage between the first electrode and the third electrode, and a DC current between the second electrode and the third electrode. 2. The electroosmotic pump according to claim 1, further comprising a second DC power source that applies a high voltage, wherein the first DC power source and the second DC power source can be separately voltage-adjusted. . First and second liquid feeding tanks each containing a first solution;
A first electrode immersed in the first solution in the first liquid feeding tank;
A second electrode immersed in the first solution in the second liquid feeding tank;
A first capillary tube having one end immersed in the first solution in the first liquid feeding tank;
A second capillary tube having one end immersed in the first solution in the second liquid feeding tank;
First to third tube portions having one ends connected so as to communicate with each other, and the other ends of the first and second capillary tubes are connected to the first and second tube portions, respectively. A first three-way joint pipe,
It said first and second internal each polarity different for Ruge Le of the capillary are fixed by chemical bonding,
Further, a predetermined amount is provided between the first electrode and the second electrode so as to generate an electroosmotic flow in the direction toward the first three-way joint tube inside the first and second capillary tubes. A first pump unit configured to include a first DC power source that applies a DC high voltage of;
Third and fourth liquid feeding tanks each containing a second solution;
A third electrode immersed in the second solution in the third liquid feeding tank;
A fourth electrode immersed in the second solution in the fourth liquid feeding tank;
A third capillary tube having one end immersed in the second solution in the third liquid feeding tank;
A fourth capillary tube having one end immersed in the second solution in the fourth liquid feeding tank;
The first to third tube portions, one end of which is connected so as to communicate with each other, and the other ends of the third and fourth capillary tubes are connected to the first and second tube portions, respectively. A second three-way joint pipe,
The third and fourth respective polarities of the interior of the capillary tube different for Ruge Le are fixed by chemical bonding,
Further, a predetermined amount is provided between the third electrode and the fourth electrode so as to generate an electroosmotic flow in the direction toward the second three-way joint tube inside the third and fourth capillary tubes. A second pump unit configured to include a second direct current power source for applying a direct current high voltage;
An electro-osmotic flow pump comprising: a connecting output line for outputting outputs from the third pipe portions of the first and second three-way joint pipes. The electroosmotic pump according to claim 3 , wherein the first DC power source and the second DC power source can be separately voltage-adjusted. A third three-way joint pipe provided with first to third pipe parts, the connected output pipes being connected so that one ends thereof can communicate with each other;
A first connecting pipe connecting the third pipe part of the first three-way joint pipe and the first pipe part of the third three-way joint pipe; and the second three-way joint pipe 4. The electroosmotic pump according to claim 3 , wherein the electroosmotic pump comprises a second connecting pipe that connects the third pipe section and the second pipe section of the third three-way joint pipe. .

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