CN115445680B - Micro-fluidic valve and micro-fluidic device - Google Patents

Abstract

The embodiment of the disclosure provides a micro-fluidic valve and a micro-fluidic device, wherein the micro-fluidic valve comprises a micro-fluidic communication unit and at least one micro-fluidic valve control unit; the micro-flow communication unit is provided with at least one micro-flow channel communicated with the receiving hole; the micro flow valve control unit includes: a first chamber filled with a first solution and a second chamber filled with a second solution, wherein the side wall of the first chamber is provided with at least one through hole; each through hole is covered with an elastic membrane for preventing the first solution from passing through; the elastic membrane can elastically stretch out of the first chamber; the elastic membrane can extend into the receiving hole so as to block the corresponding micro-flow channel; a semi-permeable membrane allowing water molecules to pass through in two directions is arranged between the first chamber and the second chamber at intervals; the electrode assembly is disposed in the second chamber and is in contact with the second solution. The micro-fluidic valve in the embodiment of the disclosure can form a solution concentration difference by controlling the electrode assembly to generate an osmotic pressure for driving the elastic membrane to block the micro-fluidic flow channel. No need of gas and liquid pump, small size, simple structure and low power consumption.

Description

Micro-fluidic valve and micro-fluidic device

Technical Field

The application relates to the technical field of environmental protection monitoring equipment, in particular to a micro-fluidic valve and a micro-fluidic device.

Background

At present, the micro-fluidic chip has more applications on environmental monitoring equipment. Micro-flow sampling is carried out from the environmental water body through the micro-fluidic chip, and then component analysis is carried out on the sampling liquid.

Microfluidic valves are important components for controlling the flow of liquids in microfluidic flow channels. However, the existing micro-fluidic valves basically use an air pump or a liquid pump as a power source for driving the valves to open and close, the valve volume is difficult to reduce, and the micro-fluidic valve is difficult to achieve. In addition, the valve needs the mutual matching of the dynamic and static mechanical parts, is relatively complex in mechanical structure, and is not beneficial to the miniaturization of the micro-fluidic valve.

Disclosure of Invention

In view of the above-mentioned shortcomings of the prior art, it is an object of the present application to provide a microfluidic valve and a microfluidic device to solve the problems in the related art.

According to a first aspect of the present disclosure, there is provided a microfluidic valve comprising: the micro-flow communication unit and at least one micro-flow valve control unit; the micro-flow communication unit is provided with at least one micro-flow channel; each micro-flow channel is provided with two open ends and an open accommodating hole; the micro flow valve control unit includes: the device comprises a first chamber filled with a first solution, wherein the side wall of the first chamber is provided with at least one through hole; each through hole is covered with an elastic membrane for preventing the first solution from passing through; the elastic membrane can be elastically stretched out of the first chamber; each through hole corresponds to one receiving hole in position, so that the elastic membrane extends into the receiving hole to block the corresponding micro-flow channel; the second chamber is filled with a second solution and communicated with the first chamber; the first solution and the second solution both have positive ions and negative ions of preset substances; the semi-permeable membrane is partitioned between the first chamber and the second chamber and allows water molecules to pass through in two directions; and the electrode assembly is arranged in the second chamber and is in contact with the second solution.

In some embodiments of the first aspect, the microfluidic communication unit and the microfluidic valve control unit are separately disposed and are separately enclosed by respective housings.

In some embodiments of the first aspect, the two open ends of each of the microfluidic channels are connected to a liquid inlet and a liquid outlet of the microfluidic chip, respectively.

In some embodiments of the first aspect, the microfluidic communication unit is arranged with a plurality of accommodating portions, each accommodating portion is provided with one microfluidic flow channel and a receiving hole communicated with the microfluidic flow channel; each accommodating part is correspondingly embedded with the micro-flow valve control unit.

In some embodiments of the first aspect, each of the microfluidic valve control units defines a plurality of through-holes, each through-hole being covered with one of the elastic membranes; the micro-flow communication unit is provided with a plurality of micro-flow channels and receiving holes communicated with the micro-flow channels, and each receiving hole corresponds to one through hole.

In some embodiments of the first aspect, the electrode assembly includes a first polarity electrode and a second polarity electrode to which a voltage is applied.

In some embodiments of the first aspect, the structure of the first and second polarity electrodes is configured as at least one of: 1) The first polar electrode and the second polar electrode are both provided with connecting columns which extend out of the micro-flow valve control unit; 2) The first polarity electrode and the second polarity electrode are overlapped; 3) The first polar electrode and the second polar electrode are in a sheet shape, a column shape or a plate shape; 4) The first and second polarity electrodes comprise a metal pattern; 5) The first polarity electrode and the second polarity electrode respectively comprise a plurality of branches which are arranged at intervals, and the branches of the first polarity electrode and the second polarity electrode are arranged in a staggered mode and are insulated from each other.

In some embodiments of the first aspect, each branch of the first and second polarity electrodes is columnar or plate-shaped; the first polar electrode and the second polar electrode take a titanium wire or a graphite rod as a framework, and porous carbon slurry is coated on the surface of the framework.

In some embodiments of the first aspect, the predetermined substance is an electrolyte.

According to a second aspect of the present disclosure, there is provided a microfluidic device comprising: the micro-fluidic chip is provided with at least one pair of liquid inlet holes and liquid outlet holes; the microfluidic valve of any one of the first aspect, wherein the open ends of each microfluidic channel are connected to the liquid inlet and outlet holes, respectively; and the valve controller is electrically connected with the electrode assembly in the at least one micro-fluidic valve control unit and used for outputting an electric signal to the electrode assembly so as to control the on-off of the corresponding micro-fluidic valve.

As described above, in the embodiments of the present disclosure, a microfluidic valve and a microfluidic device are provided, where the microfluidic valve includes a microfluidic communication unit and at least one microfluidic valve control unit; the micro-flow communication unit is provided with at least one micro-flow channel which is communicated with the receiving hole; the micro flow valve control unit includes: a first chamber filled with a first solution and a second chamber filled with a second solution respectively, wherein the side wall of the first chamber is provided with at least one through hole; each through hole is covered with an elastic membrane for preventing the first solution from passing through; the elastic membrane can be elastically stretched out of the first chamber; the elastic membrane can stretch into the accommodating hole so as to block the corresponding microfluidic flow channel; a semi-permeable membrane allowing water molecules to pass through in two directions is arranged between the first chamber and the second chamber at intervals; an electrode assembly is disposed in the second chamber and is in contact with the second solution. The micro-fluidic valve in the embodiment of the disclosure can form a solution concentration difference by controlling the electrode assembly, so as to generate a driving pressure for driving the elastic membrane to block the micro-fluidic flow channel. No need of gas and liquid pump, small size, simple structure and low power consumption.

Drawings

Fig. 1 shows a schematic structural diagram of a microfluidic valve according to an embodiment of the present disclosure.

Fig. 2 shows a schematic perspective view of a microfluidic valve according to an embodiment of the present disclosure.

FIG. 3 is a schematic perspective view of the micro flow valve control unit in the embodiment of FIG. 2.

FIG. 4 shows an exploded view of the microfluidic valve control unit of the embodiment of FIG. 2.

Fig. 5A shows a schematic cross-sectional view of a microfluidic valve in an undeformed state of an elastic membrane according to an embodiment of the present disclosure.

Fig. 5B shows a schematic cross-sectional view of a microfluidic valve in an embodiment of the present disclosure, wherein the elastic membrane is in an elastically stretched state.

FIG. 6A shows a schematic view of an electrode assembly according to an embodiment of the present disclosure.

Fig. 6B shows a schematic structural view of an electrode assembly in yet another embodiment of the present disclosure.

Fig. 6C shows a schematic structural view of an electrode assembly in yet another embodiment of the present disclosure.

Fig. 7 shows a schematic perspective view of a microfluidic valve according to another embodiment of the present disclosure.

Fig. 8 shows a schematic perspective view of a microfluidic valve according to still another embodiment of the present disclosure.

Fig. 9 is a schematic perspective view showing the micro flow communication unit and the micro flow valve control unit separated from each other and the micro flow valve control unit in the embodiment of fig. 8.

Fig. 10 shows a schematic perspective view of the microfluidic communication unit in the embodiment of fig. 8.

Detailed Description

Embodiments of the present application are described below with specific examples, and other advantages and effects of the present application will be readily apparent to those skilled in the art from the disclosure herein. The present application is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present application. It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

Embodiments of the present application will be described in detail below with reference to the accompanying drawings so that those skilled in the art to which the present application pertains can easily carry out the present application. The present application may be embodied in many different forms and is not limited to the embodiments described herein.

Reference throughout this specification to "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," or the like, means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. Furthermore, the particular features, structures, materials, or characteristics illustrated may be combined in any suitable manner in any one or more embodiments or examples. Moreover, various embodiments or examples and features of different embodiments or examples presented in this application can be combined and combined by those skilled in the art without contradiction.

Furthermore, the terms "first", "second" are used merely to denote an object and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the expressions of this application, "plurality" means two or more unless explicitly defined otherwise.

In order to clearly explain the present application, components that are not related to the description are omitted, and the same reference numerals are given to the same or similar components throughout the specification.

Throughout the specification, when a device is referred to as being "connected" to another device, this includes not only the case of being "directly connected" but also the case of being "indirectly connected" with another element interposed therebetween. In addition, when a device "includes" a certain constituent element, unless otherwise specified, it means that the other constituent element is not excluded, but may be included.

Although the terms first, second, etc. may be used herein to refer to various elements in some examples, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, the first interface and the second interface are represented. Also, as used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context indicates otherwise. It will be further understood that the terms "comprises," "comprising," "includes" and/or "including," when used in this specification, specify the presence of stated features, steps, operations, elements, modules, items, species, and/or groups, but do not preclude the presence, or addition of one or more other features, steps, operations, elements, modules, items, species, and/or groups thereof. The terms "or" and/or "as used herein are to be construed as inclusive or meaning any one or any combination. Thus, "a, B or C" or "a, B and/or C" means "any of the following: a; b; c; a and B; a and C; b and C; A. b and C ". An exception to this definition will occur only when a combination of elements, functions, steps or operations are inherently mutually exclusive in some way.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the singular forms "a", "an" and "the" include plural forms as long as the words do not expressly indicate a contrary meaning. The term "comprises/comprising" when used in this specification is taken to specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but does not exclude the presence or addition of other features, regions, integers, steps, operations, elements, and/or components.

Although not defined differently, including technical and scientific terms used herein, all terms have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terms defined in commonly used dictionaries are to be additionally interpreted as having meanings consistent with technical documents related to and the message prompted at present, and must not be excessively interpreted as having ideal or very formulaic meanings unless defined otherwise.

There is a need for miniaturisation of microfluidic devices. However, the existing microfluidic valves are basically powered by an air pump or a liquid pump to drive the valves to open and close, so that the valve volume is difficult to reduce, and the miniaturization target is difficult to realize. In addition, the mechanical valve needs the matching of a movable mechanical part and a static mechanical part, so that the structure is complicated, and the miniaturization of the micro-fluidic valve is not facilitated.

In view of this, embodiments of the present disclosure provide a microfluidic valve, which can drive the opening and closing of the valve by controlling a solution concentration difference to generate an osmotic pressure, so as to omit power sources such as an air pump and a liquid pump, and solve the problems of the related art.

Fig. 1 is a schematic diagram illustrating a schematic structural diagram of a microfluidic valve according to an embodiment of the present disclosure.

It should be noted that fig. 1 is only for illustrating the structural principle of the microfluidic valve 1, and it is not meant that the structure of the microfluidic valve 1 is limited by the size, layout, and the like in the drawings.

In fig. 1, the microfluidic valve 1 includes amicrofluidic communication unit 12 and a microfluidicvalve control unit 11. In fig. 1, themicro-flow communication unit 12 and the micro-flowvalve control unit 11 are exemplarily shown as one unit for convenience of describing the principle, and in an actual example, the number of themicro-flow communication unit 12 and the micro-flowvalve control unit 11 may be changed according to the requirement, and is not limited thereto.

Themicro-flow communication unit 12 is provided with at least onemicro-flow channel 121. Each of themicrofluidic flow paths 121 has both ends opened and has an open receiving hole. In some embodiments, two ends of themicrofluidic channel 121 may be respectively connected to a liquid inlet and a liquid outlet of the microfluidic chip, and an internal channel of the microfluidic chip is connected between the liquid inlet and the liquid outlet. Sealing rings can be arranged between the two open ends of themicro-flow channel 121 and the corresponding liquid inlet hole and the corresponding liquid outlet hole to ensure the sealing communication effect. Alternatively, in some embodiments, themicrofluidic channel 121 may be an internal channel of the microfluidic chip. In a possible example, the diameter of themicrofluidic channel 121 is 50 micrometers to 200 micrometers, and the cross-sectional shape of themicrofluidic channel 121 may be rectangular or circular.

The micro flowvalve control unit 11 includes: afirst chamber 111, asecond chamber 112, anelastic membrane 115, asemi-permeable membrane 113, and anelectrode assembly 114. Thefirst chamber 111 is filled with afirst solution 1111, and thesecond chamber 112 is filled with asecond solution 1121. Thefirst solution 1111 and thesecond solution 1121 both have positive ions and negative ions of a predetermined substance therein. The predetermined substance is an electrolyte, such as sodium chloride (NaCl), which dissolves in water to form Na⁺ And Cl^- Ions, thefirst solution 1111 and thesecond solution 1121 correspond to saline. The preset threshold is sodium chloride, which is only an example, and other types of substances including, but not limited to, other soluble salts such as sodium sulfate, magnesium sulfate, etc. are also possible, but not limited thereto.

Thefirst chamber 111 and thesecond chamber 112 are disposed in communication with each other and in a sealed communication state to prevent thefirst solution 1111 and thesecond solution 1121 from being lost. Thesemi-permeable membrane 113 is partitioned between thefirst chamber 111 and thesecond chamber 112, and thesemi-permeable membrane 113 allows water molecules to pass through in both directions and restricts the passage of predetermined substances. Therefore, when there is a difference in the predetermined substance concentration between thefirst solution 1111 and thesecond solution 1121, the transfer of water from the low concentration chamber to the high concentration chamber may occur, as indicated by an arrow a in fig. 1. It should be noted that, in the embodiment of the present disclosure, the water molecule transfer is achieved by using the concentration difference between the two chambers, which is very fast, so that the response speed of opening or closing the valve can be faster. In practical application, the response speed of the micro-fluidic valve can be further improved by selecting proper voltage, electrode shape and size, solution concentration and the like, the response speed of the micro-fluidic valve is not poor or even exceeds the response speed of some mechanical valves, and the structure simplification and the low cost can be both considered.

At least one throughhole 1112 is formed in the side wall of thefirst chamber 111, and the throughhole 1112 is covered with anelastic membrane 115 for preventing thefirst solution 1111 from passing through. Specifically, when the concentration of the predetermined substance in thesecond solution 1121 is lower than that of thefirst solution 1111, based on the principle of concentration balance, the water in thesecond chamber 112 will be transferred to thefirst chamber 111 with higher concentration of the predetermined substance, so that the volume of thefirst solution 1111 in thefirst chamber 111 is increased. As the volume of thefirst solution 1111 increases to fill thefirst chamber 111 and continues to increase, theelastic membrane 115 is squeezed and elastically and extensibly deformed outward of thefirst chamber 111, as indicated by the arrow B. The receiving hole opened by themicrofluidic communication unit 12 is disposed corresponding to the throughhole 1112, so that theelastic membrane 115 can extend from the receiving hole into themicrofluidic flow channel 121. The elastic material of theelastic membrane 115 may be configured to stretch to block themicrofluidic channel 121, thereby closing themicrofluidic channel 121. Then, if the predetermined substance concentration of thesecond solution 1121 in thesecond chamber 112 is higher than that of thefirst solution 1111, the water will be transferred from thefirst chamber 111 to thesecond chamber 112, the volume of thefirst solution 1111 in thefirst chamber 111 decreases, theelastic membrane 115 is reset under the elastic force, and themicrofluidic channel 121 is conducted.

Theelectrode assembly 114 is disposed in thesecond chamber 112 and contacts thesecond solution 1121. Theelectrode assembly 114 can adjust the concentration difference between thefirst solution 1111 and thesecond solution 1121 to control theelastic membrane 115 to block or conduct themicrofluidic flow channel 121, so as to switch the open/close state of the microfluidic valve 1. Specifically, theelectrode assembly 114 may include afirst polarity electrode 1141 and asecond polarity electrode 1142, such as a positive electrode and a negative electrode, and when theelectrode assembly 114 is energized to form a voltage between thefirst polarity electrode 1141 and thesecond polarity electrode 1142, the positive and negative ions of the predetermined substance in thesecond solution 1121 may be adsorbed, so as to reduce the concentration of the predetermined substance in thesecond solution 1121. Of course, although the positive and negative ions of the predetermined substance in thefirst solution 1111 are also attracted, the predetermined substance concentration of thefirst solution 1111 is maintained unchanged because thesemipermeable membrane 113 cannot reach thesecond chamber 112, so that the predetermined substance concentration of thesecond solution 1121 is lower than that of thefirst solution 1111, and theelastic membrane 115 is driven to elastically stretch to block themicrofluidic flow channel 121. Alternatively, by removing the voltage, for example, by shorting thefirst polarity electrode 1141 and thesecond polarity electrode 1142 or disconnecting the power supply, theelastic membrane 115 may be restored to conduct themicrofluidic flow channel 121. For thesecond solution 1121 and thefirst solution 1111, they may be named differently based on their functions, for example, thesecond solution 1121 may also be referred to as an electrode liquid, and thefirst solution 1111 may be referred to as a draw liquid.

In some embodiments, the control signal may be formed by, for example, a switching circuit to control the power supply to apply/remove the voltage to theelectrode assembly 114 to achieve different states of the microfluidic valve 1. Since themicrofluidic channel 121 is connected to the internal channel of the microfluidic chip or directly used as the internal channel of the microfluidic chip, the liquid flow in the internal channel of the microfluidic chip is controlled by the microfluidic valve 1.

It should be noted that, although fig. 1 exemplarily shows a side wall of themicrofluidic channel 121 as a side wall of thefirst chamber 111, so that in a possible embodiment, themicrofluidic communication unit 12 and the microfluidicvalve control unit 11 may be an integrated device, in other embodiments, themicrofluidic communication unit 12 and the microfluidicvalve control unit 11 may be separately disposed and respectively enclosed by respective housings.

As shown in fig. 2, a schematic perspective view of a microfluidic valve according to an embodiment of the present disclosure is shown.

In fig. 2, themicrofluidic communication unit 22 and the microfluidicvalve control unit 21 of the microfluidic valve are separately arranged, and the functional relationship between them is the cooperation of theelastic membrane 215 and the receivinghole 222 of themicrofluidic channel 221. As shown in fig. 2, 3 and 4, fig. 3 shows a schematic perspective view of the microfluidicvalve control unit 21 in the embodiment of fig. 2. Fig. 4 shows a schematic exploded view of the microfluidicvalve control unit 21 of the embodiment of fig. 2.

In fig. 2, 3 and 4, the miniflowvalve control unit 21 may take the shape of a square, the bottom of which is provided with theelastic membrane 215. Thefirst polarity electrode 2141 and thesecond polarity electrode 2142 included in the electrode assembly 214 may extend beyond the microfluidicvalve control unit 21 to facilitate connection to a power source for applying a voltage. Specifically, thefirst polarity electrode 2141 and thesecond polarity electrode 2142 may be formed of a connecting post and a main body portion. The top of the microfluidicvalve control unit 21 extends out of thefirst connection post 21411 of thefirst polarity electrode 2141 and thesecond connection post 21421 of thesecond polarity electrode 2142 in the electrode assembly 214, and thefirst connection post 21411 and thesecond connection post 21421 may be cylindrical in shape as an example. As shown in fig. 4, the package case of the micro flowvalve control unit 21 may include anupper case 2122 and alower case 2112 combined with each other to form a receiving space. The top of theupper shell 2122 is provided with a first connectingpost 21411 and a second connectingpost 21421 extending and protruding therefrom. The firstmain portion 21412 of thefirst polarity electrode 2141 and themain portion 21422 of thesecond polarity electrode 2142 may be plates stacked on top of each other, as shown in fig. 4 and 6A. And referring to fig. 4, 5A and 5B, asemi-permeable membrane 213 is disposed under the first andsecond polarity electrodes 2141 and 2142 to divide the receiving space into afirst chamber 211 and asecond chamber 212 which are distributed up and down. The bottom of thelower case 2112 is provided with a through hole (shown in fig. 5A and 5B) and anelastic membrane 215 covering the through hole. Although theelastic membrane 215 in fig. 2, 3 and 4 is exemplarily elastically stretched outward, it may be in an undeformed flat plate shape in other examples, which are not illustrated as a limitation.

Reference may be made to fig. 5A and 5B, which are schematic cross-sectional views of themicrofluidic communication unit 22 and the microfluidicvalve control unit 21 shown in fig. 2 to 4, taken in a longitudinal direction after they are combined. The difference is that theelastic membrane 215 in fig. 5A is in an undeformed state, and themicrofluidic channel 221 is in an open state. Referring again to fig. 5B, theelastic membrane 215 is in a state of being elastically stretched to block themicrofluidic channel 221 from the receivinghole 222. Specifically, in the case where no voltage is applied to the electrode assembly 214, theelastic membrane 215 is in an unstretched state, i.e., as shown in fig. 5A. Further, when a voltage is applied to the electrode assembly 214, the predetermined concentration of the second solution (such as NaCl) begins to decrease, and water in the second solution is transferred into the high concentration of the first solution, so as to enter thefirst chamber 211, and the pressure generated thereby presses theelastic membrane 215 to be deformed by elastic expansion so as to block themicrofluidic channel 221. As shown in fig. 5B.

In some embodiments, the shape, number and size of the first polarity electrode and the second polarity electrode in the electrode assembly can be changed, so that the adsorption efficiency of the first polarity electrode and the second polarity electrode on ions is changed, the dead volume of the electrode solution in the second chamber is reduced, the solution concentration is changed more quickly, and the response speed of the valve can be optimized.

In some embodiments, the structure of the first and second polarity electrodes is configured as at least one of the following.

1) The first polar electrode and the second polar electrode are both provided with connecting columns which extend out of the micro-flow valve control unit; 2) The first polarity electrode and the second polarity electrode are overlapped; 3) The first polar electrode and the second polar electrode are in a sheet shape, a column shape or a plate shape; 4) The first and second polarity electrodes comprise a metal pattern; 5) The first polarity electrode and the second polarity electrode respectively comprise a plurality of branches which are arranged at intervals, and the branches of the first polarity electrode and the second polarity electrode are arranged in a staggered mode and are insulated from each other.

The above-described first polarity electrode and second polarity electrode may be used in combination, and a plurality of examples will be described below.

For example, in the example of fig. 6A, a schematic top view of a plate-shaped body in which a first polarity electrode and a second polarity electrode are stacked is shown, and thefirst polarity electrode 2141 and thesecond polarity electrode 2142 respectively have afirst connection column 21411 and asecond connection column 21421 extending outward of the miniflow valve control unit, and respectively havemain body portions 21412, 21422.

For another example, in the example of fig. 6B, thefirst polarity electrode 3141 and thesecond polarity electrode 3142 may have afirst connection column 31411 and asecond connection column 31421, respectively, which are provided to extend outward of the micro flow valve control unit. The first andsecond polarity electrodes 3141 and 3142 include metal patterns, and particularly, thebody portions 31412 and 31422 of the first andsecond polarity electrodes 3141 and 3142 are metal patterns, which may be manufactured by a screen printing or doctor blade process. The metal patterns of thefirst polarity electrode 3141 and thesecond polarity electrode 3142 may each include a plurality of branches arranged at intervals, such as the illustrated fishbone shape, or may be a fork shape. The branches of thefirst polarity electrode 3141 and thesecond polarity electrode 3142 are alternately arranged and insulated from each other, so that the overall layout can be more compact and the volume of the first chamber can be reduced.

For another example, in the example of fig. 6C, thefirst polarity electrode 4141 and thesecond polarity electrode 4142 may each include a plurality of branches arranged at intervals, the plurality of branches are arranged at intervals in a staggered manner, and each branch is in a column shape. Alternatively, each branch may be plate-shaped, and may be shown as a side of a plate-shaped branch in the illustration. In a possible example, the first andsecond polarity electrodes 4141 and 4142 (including each branch) may be a titanium wire or a graphite rod as a skeleton, and a porous carbon slurry is coated on a surface of the skeleton. Wherein the thickness of the porous carbon portion is controllable, e.g., between 100-500 microns.

Although the elastic membrane and the micro flow channels may be in a one-to-one correspondence relationship, in other embodiments, the number relationship between the micro flow valve control unit and the elastic membrane, the number relationship between the micro flow communication unit and the micro flow channels, and the number relationship between the micro flow valve control unit and the micro flow communication unit may also be varied.

For example, as shown in fig. 7, each of the micro flowvalve control units 51 may be formed with a plurality of through holes, for example, two through holes. Each through hole is covered with one of theelastic membranes 515, which is exemplarily shown as twoelastic membranes 515 arranged in the transverse direction in fig. 7. Accordingly, themicrofluidic communication unit 52 is provided with a plurality ofmicrofluidic channels 521 and receivingholes 522 communicating with the microfluidic channels, for example, two microfluidic channels arranged laterally in the figure, where the receiving hole of each microfluidic channel corresponds to one of the through holes. Therefore, the micro flowvalve control unit 51 can control the blockage or the conduction of the twomicro flow channels 521. In some embodiments, the microfluidicvalve control unit 51 may be provided with only one first chamber, and the twoelastic membranes 515 may correspond to the same first chamber, so as to synchronously perform elastic expansion or recovery to synchronously control the blockage or conduction of two microfluidic channels. Alternatively, in other embodiments, the micro flowvalve control unit 51 may be provided with two first chambers, and the twoelastic membranes 515 may belong to different first chambers, so that the blocking or the communication of two micro flow channels may be controlled independently.

For example, as shown in fig. 8, 9 and 10, a structure of a microfluidic valve according to another embodiment of the present disclosure is shown. Fig. 8 shows a schematic combined perspective structure of the microfluidic valve in this embodiment. Fig. 9 is a schematic perspective view showing the separated and disassembled structure of each micro-flow valve control unit and the micro-flow communication unit in the present embodiment. Fig. 10 is a schematic perspective view of a microfluidic communication unit according to the present embodiment.

In this embodiment, as shown in fig. 10, themicrofluidic communication unit 62 is arranged with a plurality of receivingportions 623, and each receivingportion 623 may be a concave portion. Each receivingportion 623 is provided with themicrofluidic channel 621 and a receivinghole 622 communicating with themicrofluidic channel 621, and in the figure, the receivinghole 622 is provided on the bottom surface of the receivingportion 623 and communicates with themicrofluidic channel 621 therebelow. As shown in fig. 8 and 9, eachaccommodating portion 623 is embedded with one micro flowvalve control unit 61. Compared with the embodiment shown in fig. 7, in the embodiments shown in fig. 8 to 10, the volume of themicrofluidic communication unit 62 and the number of the microfluidicvalve control units 61 are increased, so that the number of controllable channels of themicrofluidic channels 621 is increased, and the operation of a larger number of microfluidic chips is conveniently controlled.

A microfluidic device may also be provided in embodiments of the present disclosure.

The microfluidic device comprises: the micro-fluidic chip is provided with at least one pair of liquid inlet holes and liquid outlet holes; the microfluidic valve of any one of the preceding embodiments, wherein the open ends of each microfluidic channel are connected to the inlet well and the outlet well, respectively;

and the valve controller is electrically connected with the electrode assembly in the at least one micro-fluidic valve control unit and used for outputting an electric signal to the electrode assembly so as to control the on-off of the corresponding micro-fluidic valve. In some embodiments, the valve controller may be implemented by, for example, an MCU or other processing chip, or may be implemented by a processing chip in cooperation with a circuit (e.g., a switching circuit) to control the opening and closing of the microfluidic valve according to a preset timing sequence or a trigger condition.

In a specific application example, the microfluidic device may be mounted as a component or a constituent unit to an environmental monitoring apparatus, such as an environmental water sample monitoring apparatus. The environmental water sample monitoring equipment takes the liquid to be detected from the environment, sends the sampling liquid into the microfluidic chip through the microfluidic valve, and further performs component analysis through optical detection and other means.

In addition, it can be understood that the microfluidic device in the embodiments of the present disclosure may also be applied to fields such as biomedicine, synthesis and screening of new drugs, food and commodity inspection, environmental monitoring, criminal science, military science, and aerospace science, such as applications of nucleic acid separation and quantification, DNA sequencing, gene mutation and gene differential expression analysis, protein screening, drug research, etc., in the biomedicine field, and the application is very wide and has a very high commercial value.

In summary, the present disclosure provides a microfluidic valve and a microfluidic device, where the microfluidic valve includes a microfluidic communication unit and at least one microfluidic valve control unit; the micro-flow communication unit is provided with at least one micro-flow channel which is communicated with the receiving hole; the micro flow valve control unit includes: a first chamber filled with a first solution and a second chamber filled with a second solution respectively, wherein the side wall of the first chamber is provided with at least one through hole; each through hole is covered with an elastic membrane for preventing the first solution from passing through; the elastic membrane can be elastically stretched out of the first chamber; the elastic membrane can stretch into the receiving hole so as to block the corresponding micro-flow channel; a semi-permeable membrane allowing water molecules to pass through in two directions is arranged between the first chamber and the second chamber at intervals; an electrode assembly is disposed in the second chamber and is in contact with the second solution. The microfluidic valve in the embodiment of the disclosure can form a solution concentration difference by controlling the electrode assembly, so as to generate a driving pressure for driving the elastic membrane to block the microfluidic flow channel. No need of gas and liquid pump, small size, simple structure and low power consumption.

The above embodiments are merely illustrative of the principles and utilities of the present application and are not intended to limit the application. Any person skilled in the art can modify or change the above-described embodiments without departing from the spirit and scope of the present application. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical concepts disclosed in the present application shall be covered by the claims of the present application.

Claims (9)

1. A microfluidic valve, comprising:

the micro-flow communication unit and at least one micro-flow valve control unit;

the micro-flow communication unit is provided with at least one micro-flow channel; each micro-flow channel is provided with two open ends and an open accommodating hole;

the micro flow valve control unit includes:

the device comprises a first chamber filled with a first solution, wherein the side wall of the first chamber is provided with at least one through hole; each through hole is covered with an elastic membrane for preventing the first solution from passing through; the elastic membrane can be elastically stretched out of the first chamber; each through hole corresponds to one receiving hole in position, so that the elastic membrane extends into the receiving hole to block the corresponding micro-flow channel;

the second chamber is filled with a second solution and communicated with the first chamber; the first solution and the second solution both have positive ions and negative ions of preset substances;

the semi-permeable membrane is partitioned between the first chamber and the second chamber and allows water molecules to pass through in two directions;

an electrode assembly disposed in the second chamber and in contact with the second solution;

the electrode assembly includes first and second polarity electrodes to which a voltage is applied, the first and second polarity electrodes constituting positive and negative electrodes.

2. The microfluidic valve according to claim 1, wherein the microfluidic communication unit and the microfluidic valve control unit are separately disposed and are respectively encapsulated by respective housings.

3. The microfluidic valve of claim 1, wherein the two open ends of each microfluidic channel are connected to a liquid inlet and a liquid outlet of the microfluidic chip, respectively.

4. The microfluidic valve according to claim 1, wherein the microfluidic communicating unit is arranged with a plurality of receiving portions, each receiving portion is provided with a microfluidic channel and a receiving hole communicated with the microfluidic channel; each accommodating part is correspondingly embedded with the micro-flow valve control unit.

5. The microfluidic valve of claim 1, wherein each of the microfluidic valve control units forms a plurality of through holes, each of the through holes being covered with one of the elastic membranes; the micro-flow communication unit is provided with a plurality of micro-flow channels and receiving holes communicated with the micro-flow channels, and each receiving hole corresponds to one through hole.

6. The microfluidic valve of claim 1, wherein the first and second polarity electrodes are structurally configured to be at least one of:

the first polar electrode and the second polar electrode are both provided with connecting columns which extend out of the micro-flow valve control unit;

the first polarity electrode and the second polarity electrode are overlapped;

the first polar electrode and the second polar electrode are in a sheet shape, a column shape or a plate shape;

the first and second polarity electrodes include a metal pattern;

the first polarity electrode and the second polarity electrode respectively comprise a plurality of branches which are arranged at intervals, and the branches of the first polarity electrode and the second polarity electrode are arranged in a staggered mode and are insulated from each other.

7. The microfluidic valve according to claim 6, wherein each branch of the first and second polarity electrodes is columnar or plate-shaped; the first polar electrode and the second polar electrode take a titanium wire or a graphite rod as a framework, and porous carbon slurry is coated on the surface of the framework.

8. Microfluidic valve according to claim 1, wherein the predetermined substance is an electrolyte.

9. A microfluidic device, comprising:

the micro-fluidic chip is provided with at least one pair of liquid inlet holes and liquid outlet holes;

the microfluidic valve of any one of claims 1 to 8, wherein the open ends of each microfluidic channel are connected to the inlet and outlet wells, respectively;

and the valve controller is electrically connected with the electrode assembly in the at least one micro-fluidic valve control unit and used for outputting an electric signal to the electrode assembly so as to control the on-off of the corresponding micro-fluidic valve.

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