阅读说明：本技术 微流动气控芯片 (Micro-flow air control chip ) 是由 周侗 顾志鹏 刘仁源 王伟 张意如 于 2020-04-30 设计创作，主要内容包括：本发明提供的一种微流动气控芯片,涉及微流控技术领域,包括：气控层,气控层的内表面开设至少一个微阀室和至少一个微泵室；流控层的内表面开设至少一条微流通道,每条微流通道包括至少两条不连续的单元流道；隔膜层密封装配在气控层和流控层之间,微阀室和微泵室与外部连通；隔膜层为柔性薄膜,微阀室对应覆盖相邻单元流道的一部分,微泵室对应覆盖微流通道的首端或末端,隔膜层在负压状态下朝向微阀室和/或微泵室的内腔形变,在微泵室、微阀室和单元流道之间形成通路。该气控芯片不会出现泄露,还可减少高集成芯片中微泵/微阀结构的数量,在优化了结构冗杂性的同时,也有效的提升了气控芯片的可靠性,降低了成本。(The invention provides a micro-flow pneumatic control chip, which relates to the technical field of micro-flow and comprises the following components: the inner surface of the pneumatic control layer is provided with at least one micro valve chamber and at least one micro pump chamber; the inner surface of the flow control layer is provided with at least one micro-flow channel, and each micro-flow channel comprises at least two discontinuous unit flow channels; the diaphragm layer is hermetically assembled between the pneumatic control layer and the flow control layer, and the micro valve chamber and the micro pump chamber are communicated with the outside; the diaphragm layer is a flexible film, the micro valve chamber correspondingly covers a part of the adjacent unit flow channel, the micro pump chamber correspondingly covers the head end or the tail end of the micro flow channel, and the diaphragm layer deforms towards the inner cavity of the micro valve chamber and/or the micro pump chamber under the negative pressure state to form a passage among the micro pump chamber, the micro valve chamber and the unit flow channel. The pneumatic control chip has the advantages that leakage cannot occur, the number of micropump/micro valve structures in a high integrated chip can be reduced, the reliability of the pneumatic control chip is effectively improved while the structural redundancy is optimized, and the cost is reduced.)

1. A microfluidic pneumatic chip, comprising:

the inner surface of the pneumatic control layer is provided with at least one micro valve chamber and at least one micro pump chamber;

the inner surface of the flow control layer is provided with at least one micro-flow channel, and each micro-flow channel comprises at least two discontinuous unit flow channels;

a diaphragm layer sealingly fitted between the gas control layer and the fluidic layer, the micro-valve chamber and the micro-pump chamber communicating with the outside; the diaphragm layer is a flexible film, the micro valve chamber correspondingly covers a part of the adjacent unit flow channel, the micro pump chamber correspondingly covers the head end or the tail end of the micro flow channel, the diaphragm layer deforms towards the micro valve chamber and/or the inner cavity of the micro pump chamber under the negative pressure state, and a passage is formed among the micro pump chamber, the micro valve chamber and the unit flow channel.

2. A microfluidic pneumatic chip according to claim 1, further comprising:

the first air path and/or the second air path;

the first air path and/or the second air path are/is arranged in the air control layer; one end of the first air path is communicated with the micro valve chamber, the other end of the first air path is communicated with the outside, one end of the second air path is communicated with the micro pump chamber, and the other end of the second air path is communicated with the outside.

3. A microfluidic pneumatic chip according to claim 2, further comprising:

the interface groove is formed in the outer portion of the pneumatic control layer, and the first air path and the second air path are communicated with the interface groove.

4. The microfluidic pneumatic chip of claim 1, wherein the micro valve chamber and/or the micro pump chamber is a cambered groove formed in an inner surface of the pneumatic control layer.

5. The microfluidic pneumatic chip of any one of claims 1-4, wherein each of the microfluidic channels is associated with two of the micropump chambers, and the two micropump chambers respectively cover a head end and a tail end of the microfluidic channel.

6. The microfluidic pneumatic chip of any one of claims 1-4, wherein each of the micro pump chambers covers a head end and a tail end of the adjacent micro flow channels, and the micro flow channels are adjacent to each other end to form a closed loop structure.

7. The microfluidic pneumatic chip of any one of claims 1-4, further comprising:

and the fixing chamber is arranged on the inner surface of the flow control layer and communicated with the microfluidic channel.

8. The microfluidic pneumatic chip of claim 7, wherein the first ends of the microfluidic channels are in communication with the same fixed chamber, and the second ends of the microfluidic channels are covered by the pumping chambers.

9. The microfluidic pneumatic chip of claim 8, further comprising:

a third gas path;

the third air path is arranged in the air control layer and is opposite to the fixed cavity.

10. The microfluidic pneumatic chip of claim 7, wherein the first ends of the microfluidic channels are in one-to-one correspondence with the fixed chambers, and the same one of the micropump chambers is covered by the end of the microfluidic channels.

Technical Field

The invention relates to the technical field of microfluidics, in particular to a micro-fluidic pneumatic control chip.

Background

The Micro-fluidic chip (Micro fluidics) can integrate basic operation units of sample preparation, reaction, separation, detection and the like in the processes of biological, chemical and medical analysis on a single micron-scale chip, and automatically complete the whole analysis process. The chip is based on the transportation and control of microfluidic liquid in a microchannel, so that the existing microfluidic pneumatic control chip integrates a large number of micropumps and microvalves in order to realize the effective transportation and control of the microfluidic liquid.

However, the existing micro-flow pneumatic control chip has a complex internal structure due to the massive construction of its internal micro-pumps and micro-valves, which directly results in a relatively complex manufacturing process of the chip and a high manufacturing cost.

Disclosure of Invention

The invention aims to provide a micro-flow pneumatic control chip to solve the technical problem of complex internal structure of the chip in the prior art.

The invention provides a micro-flow pneumatic control chip, which comprises:

the inner surface of the pneumatic control layer is provided with at least one micro valve chamber and at least one micro pump chamber;

the inner surface of the flow control layer is provided with at least one micro-flow channel, and each micro-flow channel comprises at least two discontinuous unit flow channels;

a diaphragm layer sealingly fitted between the gas control layer and the fluidic layer, the micro-valve chamber and the micro-pump chamber communicating with the outside; the diaphragm layer is a flexible film, the micro valve chamber correspondingly covers a part of the adjacent unit flow channel, the micro pump chamber correspondingly covers the head end or the tail end of the micro flow channel, the diaphragm layer deforms towards the micro valve chamber and/or the inner cavity of the micro pump chamber under the negative pressure state, and a passage is formed among the micro pump chamber, the micro valve chamber and the unit flow channel.

Further, the micro-flow pneumatic control chip further comprises:

the first air path and/or the second air path;

the first air path and/or the second air path are/is arranged in the air control layer; one end of the first air path is communicated with the micro valve chamber, the other end of the first air path is communicated with the outside, one end of the second air path is communicated with the micro pump chamber, and the other end of the second air path is communicated with the outside.

Further, the micro-flow pneumatic control chip further comprises:

the interface groove is formed in the outer portion of the pneumatic control layer, and the first air path and the second air path are communicated with the interface groove.

Further, the micro valve chamber and/or the micro pump chamber are arc-surface grooves formed in the inner surface of the pneumatic control layer.

Furthermore, each microfluidic channel is matched with two micropump chambers, and the two micropump chambers respectively cover the head end and the tail end of the microfluidic channel correspondingly.

Furthermore, each micro-pump chamber correspondingly covers the head end and the tail end of the adjacent micro-flow channels, and the plurality of micro-flow channels are adjacent end to form a closed loop structure.

Further, the micro-flow pneumatic control chip further comprises:

and the fixing chamber is arranged on the inner surface of the flow control layer and communicated with the microfluidic channel.

Furthermore, the head ends of the micro flow channels are correspondingly communicated with the same fixed chamber, and the micro pump chambers are correspondingly covered with the tail ends of the micro flow channels one by one.

Further, the micro-flow pneumatic control chip further comprises:

a third gas path;

the third air path is arranged in the air control layer and is opposite to the fixed cavity.

Furthermore, the head ends of the micro flow channels are communicated with the fixed chambers in a one-to-one correspondence mode, and the same micro pump chamber is correspondingly covered with the tail ends of the micro flow channels.

In the above technical solution, when a positive pressure is input to the micro pump chamber or the micro valve chamber, the membrane layer adheres to the inner surface of the fluidic layer to inhibit the microfluidic liquid from flowing in the microfluidic channel. When negative pressure is input into the micro pump chamber or the micro valve chamber, the diaphragm layer deforms towards the micro valve chamber or the micro pump chamber, the micro-flow liquid is sucked into a vacuum area between the diaphragm layer and the flow control layer, and even under the limit pressure, the diaphragm layer can deform to be attached to the wall surface of the inner cavity wall of the micro pump chamber or the micro valve chamber, so that the micro pump chamber is filled with the micro-flow liquid. The micro-flow liquid flow is indirectly controlled by controlling the deformation of the diaphragm layer, the problem that reactants are leaked to the atmosphere can not occur in the control process, and therefore the problem of reactant waste or pollution can not be caused. And the structure of the micropump chamber is directly used as a reaction chamber or a liquid storage chamber, so that the number of the micropump chambers or the micropump chambers in a complex microfluidic system can be greatly reduced. The diaphragm layer can reduce the whole pressure of gas accuse system, reduces and reveals the risk. Therefore, the structure of the pneumatic control chip optimizes the structural redundancy, effectively improves the reliability of the pneumatic control chip and reduces the requirements and cost of the production process.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a perspective view of a microfluidic pneumatic chip according to one embodiment of the present invention;

FIG. 2 is a side view of the microfluidic pneumatic chip of FIG. 1;

FIG. 3 is an exploded view of the microfluidic pneumatic chip of FIG. 1;

FIG. 4 is a perspective view of a fluidic layer provided in accordance with one embodiment of the present invention;

FIG. 5 is a cross-sectional view of the microfluidic pneumatic chip of FIG. 1;

FIG. 6 is a cross-sectional view 2 of the microfluidic pneumatic chip of FIG. 1;

FIG. 7 is a cross-sectional view of the microfluidic pneumatic chip of FIG. 1;

FIG. 8 is a diagram of a state of deformation of a membrane layer according to an embodiment of the present invention;

FIG. 9 is a diagram of a state of deformation of a membrane layer provided in accordance with an embodiment of the present invention 2;

FIG. 10 is a diagram of a state of deformation of a membrane layer provided in accordance with an embodiment of the present invention 3;

FIG. 11 is a diagram of a state of deformation of a diaphragm layer provided in accordance with an embodiment of the present invention 4;

FIG. 12 is an assembled perspective view of a fluidic layer provided in accordance with another embodiment of the present invention;

FIG. 13 is a perspective view of a microfluidic pneumatic chip according to another embodiment of the present invention;

FIG. 14 is a side view of the microfluidic pneumatic chip of FIG. 13;

FIG. 15 is an exploded view of the microfluidic pneumatic chip of FIG. 13;

FIG. 16 is a perspective view of a fluidic layer with fixed chambers provided by one embodiment of the present invention;

fig. 17 is a plan view of the fluidic layer shown in fig. 16;

FIG. 18 is an assembled perspective view of the fluidic layer shown in FIG. 16;

FIG. 19 is a perspective view of a fluidic layer with fixed chambers provided in accordance with another embodiment of the present invention;

fig. 20 is a plan view of the fluidic layer shown in fig. 19;

FIG. 21 is a perspective view of an assembly of fluidic layers with fixed chambers provided in accordance with yet another embodiment of the present invention;

fig. 22 is a perspective view of an assembly of fluidic layers with fixed chambers according to yet another embodiment of the present invention.

Reference numerals:

1. a pneumatic control layer; 2. a fluidic layer; 3. a separator layer;

11. a micro-valve chamber; 12. a micropump chamber; 13. a first gas path; 14. a second gas path;

15. an interface slot; 21. a microfluidic channel; 22. a unit flow channel; 23. the chamber is fixed.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

As shown in fig. 1 to fig. 3, the micro-fluidic pneumatic chip provided in this embodiment includes:

the air control layer 1, wherein at least one micro valve chamber 11 and at least one micro pump chamber 12 are arranged on the inner surface of the air control layer 1;

the device comprises a flow control layer 2, wherein at least one micro-flow channel 21 is formed in the inner surface of the flow control layer 2, and each micro-flow channel 21 comprises at least two discontinuous unit flow channels 22;

a diaphragm layer 3, wherein the diaphragm layer 3 is hermetically assembled between the air control layer 1 and the flow control layer 2, and the micro valve chamber 11 and the micro pump chamber 12 are communicated with the outside; the diaphragm layer 3 is a flexible film, the micro valve chamber 11 correspondingly covers a part of the adjacent unit flow channel 22, the micro pump chamber 12 correspondingly covers the head end or the tail end of the micro flow channel 21, the diaphragm layer 3 deforms towards the micro valve chamber 11 and/or the inner cavity of the micro pump chamber 12 in a negative pressure state, and a passage is formed among the micro pump chamber 12, the micro valve chamber 11 and the unit flow channel 22.

As shown in fig. 4 to 12, the microfluidic pneumatic chip includes a pneumatic control layer 1, a membrane layer 3, and a fluidic control layer 2, where the membrane layer 3 is a flexible film, and the flexible film does not need to be bonded by a chemical agent like a hard membrane, so that the leakage risk and the processing cost can be reduced, and the microstructure is not damaged. The high-elasticity film with stable performance is preferred, the high-elasticity film has small elasticity modulus and easy deformation, the requirement on air pressure in the deformation process is low, the requirement on an air control system can be reduced, and the leakage risk is reduced. Wherein the high elasticity film can be thickened properly for optimizing the sealing performance between the pneumatic control layer 1 and the flow control layer 2.

Sealing modes such as double-sided adhesive, mechanical pressing, bonding and the like can be adopted between the diaphragm layer 3 and the pneumatic control layer 1 and the flow control layer 2. After the pneumatic control layer 1, the diaphragm layer 3 and the fluidic control layer 2 are assembled, the pressure state of the inner cavity of the micro-pump chamber 12 may be controlled, and preferably, the pressure state (one of the pressure states) of the inner cavity of the micro-pump chamber 12 may be selectively controlled, so that the corresponding portion of the diaphragm layer 3 is deformed toward the inner cavity of the micro-pump chamber 12 by the pressure difference, and the vacuum space formed between the diaphragm layer 3 and the fluidic control layer 2 by the deformation may be used as a reaction chamber or a liquid storage chamber. Similarly, the pressure state of the inner cavity of the micro valve chamber 11 can be controlled, so that the corresponding part of the diaphragm layer 3 deforms towards the inner cavity of the micro valve chamber 11 due to the pressure difference, and the vacuum space formed between the diaphragm layer 3 and the flow control layer 2 due to the deformation can be used for communicating the adjacent unit flow channels 22 in the micro flow channel 21.

The micro valve chambers 11 and/or the micro pump chambers 12 are arc-shaped grooves, preferably spherical grooves, that is, concave dome-shaped grooves, formed on the inner surface of the pneumatic control layer 1. When the magnitude of the negative pressure is limited, the diaphragm layer 3 may be bonded to the inner cavity wall of the micro-valve chamber 11 or the inner cavity wall of the micro-pump chamber 12 in the negative pressure state, and the shape and structure of the reaction chamber or the liquid storage chamber may be determined by the shape and structure of the micro-pump chamber 12. In addition, other matched microstructures including a reagent pre-buried groove, a microelectrode, a silicon column, a chromatography material, a reagent mixing structure and the like can be added at the corresponding position of the micro-pump chamber 12 of the flow control layer 2 according to requirements. The membrane layer 3 may be surface treated according to the liquid properties and flow requirements, but is not limited thereto.

With continued reference to fig. 5-7, the microfluidic pneumatic chip further includes: a first gas circuit 13 and/or a second gas circuit 14; the first air path 13 and/or the second air path 14 are/is arranged inside the air control layer 1; one end of the first air passage 13 is communicated with the micro valve chamber 11, the other end of the first air passage 13 is communicated with the outside, one end of the second air passage 14 is communicated with the micro pump chamber 12, and the other end of the second air passage 14 is communicated with the outside. The micro valve chamber 11 and the micro pump chamber 12 are communicated with the outside, and the micro pump chamber 11 and the micro pump chamber 12 can be realized by arranging the first air passage 13 and the second air passage 14 in the air control layer 1, so that the air pressure state of the micro pump chamber 12 or the micro valve chamber 11 can be stably and effectively controlled.

As shown in fig. 13 to 15, the micro flow pneumatic control chip further includes: the interface slot 15 is arranged outside the pneumatic control layer 1, and the first air passage 13 and the second air passage 14 are communicated with the interface slot 15. The interface slot 15 can be used for centralizing a plurality of first air paths 13 and second air paths 14, and is uniformly controlled by the air path positive and negative pressure switching module, so that the operation is convenient. The external air source can provide high-frequency positive and negative air pressure switching effect to meet different requirements of reagent transportation, mixing and the like. A person skilled in the art may set a specific air path structure or number of the first air path 13 or the second air path 14 according to a requirement, and is not limited herein.

It should be noted that the fluidic layer 2 may be provided with a plurality of microfluidic channels 21, the microfluidic channels 21 may work alone or in combination, and in combination with this, the pneumatic control layer 1 may also be provided with a plurality of microfluidic chambers 11 or micropump chambers 12. For example, as shown in fig. 5, each of the micro flow channels 21 is associated with two micro pump chambers 12, and the two micro pump chambers 12 respectively cover the head end and the tail end of the micro flow channel 21. Alternatively, as shown in fig. 12, each of the micro pump chambers 12 covers the head end and the tail end of the adjacent micro flow channel 21, and a plurality of the micro flow channels 21 are adjacent to each other end to form a closed loop structure. The skilled person can arrange the matching structure between the microfluidic channel 21 and the microvalve chamber 11 and the micropump chamber 12 according to the requirement, and the invention is not limited herein.

Taking the structure shown in fig. 1 to 11 as an example, the microfluidic pneumatic chip has two micro-pump valves, which are respectively located at the head end and the tail end of a microfluidic channel 21, and can form a vacuum space between the diaphragm layer 3 and the fluidic layer 2 as a reaction chamber or a liquid storage chamber by deformation of the corresponding portion of the diaphragm layer 3 toward the two micro-pump valves. As shown in fig. 5, when positive pressure is input to the micro valve chamber 11 and the micro pump chamber 12, the diaphragm layer 3 is attached to the inner surface of the flow control layer 2, the diaphragm layer 3 blocks the adjacent cell flow channel 22, and also blocks the space between the micro flow channel 21 and the micro pump chamber 12, so that the micro valve chamber 11 is controlled to be in a closed state, and the micro flow liquid cannot flow in the micro flow channel 21.

Prior to the experiment, microfluidic liquid may be stored in the reservoir formed between the membrane layer 3 and the fluidic layer 2, where it is not able to flow in the microfluidic channel 21, ready for the experiment. The mode of storing the micro-flow liquid in the liquid storage chamber in advance can be realized by arranging a related infusion passage on the micro-flow pneumatic control chip, or the micro-flow pneumatic control chip is stored in advance before the pneumatic control layer 1, the diaphragm layer 3 and the flow control layer 2 are assembled, and the micro-flow pneumatic control chip can be set by a person skilled in the art according to needs, and is not described herein.

In an experiment, in order to introduce the micro-flow liquid into the reaction chamber from the liquid storage chamber, the positive pressure of the micro-valve chamber 11 can be switched to negative pressure, at this time, the part of the diaphragm layer 3 corresponding to the micro-valve chamber 11 deforms towards the micro-valve chamber 11 due to the action of the negative pressure, so that the adjacent unit flow channels 22 are communicated, and the micro-flow channels 21 communicated with the adjacent unit flow channels 22 can be used for the micro-flow liquid to flow in the micro-flow channels. At this time, the microfluidic liquid can be introduced from the liquid storage chamber into the reaction chamber through the microfluidic channel 21 by adjusting the pressure difference between the liquid storage chamber and the reaction chamber.

Specifically, referring to fig. 6 and 7 in combination with fig. 8 to 11, the input air pressure of the micro pump chamber 12 as the reaction chamber can be controlled to be changed from positive pressure to negative pressure, and the portion of the diaphragm layer 3 corresponding to the micro pump chamber 12 is deformed toward the micro pump chamber 12 by the negative pressure, so as to form the reaction chamber in the micro pump chamber 12. At the same time, the microfluidic liquid can be sucked into the reaction chamber under negative pressure via the microfluidic channel 21 and the microvalve chamber 11. In addition, the air pressure of the liquid storage chamber can be controlled to be higher than that of the reaction chamber, and the microfluidic liquid can be pushed into the reaction chamber through the microfluidic channel 21 and the microvalve chamber 11 by the pressure difference between the liquid storage chamber and the reaction chamber, instead of independently changing the air pressure of the reaction chamber from positive pressure to negative pressure. After the drainage is completed, the micro valve chamber 11 is switched back to positive pressure, and the adjacent unit flow channel 22 is closed, that is, the micro flow channel 21 is closed.

In an experiment, in order to guide the micro-flow liquid back to the liquid storage chamber from the reaction chamber, the positive pressure of the micro-valve chamber 11 can be switched to negative pressure, and at the moment, the part, corresponding to the micro-valve chamber 11, of the diaphragm layer 3 deforms towards the micro-valve chamber 11 under the action of the negative pressure, so that the adjacent unit flow channels 22 are communicated, and the micro-flow channels 21 communicated with the adjacent unit flow channels 22 can be used for the micro-flow liquid to circulate in the micro-flow channels. At this point, the pressure difference between the reaction chamber and the reservoir chamber is adjusted to allow the microfluidic liquid to be conducted back from the reaction chamber to the reservoir chamber through the microfluidic channel 21.

Similarly, the input air pressure of the micro pump chamber 12 serving as the reservoir can be controlled to be changed from positive pressure to negative pressure, and the portion of the diaphragm layer 3 corresponding to the micro pump chamber 12 is deformed toward the micro pump chamber 12 by the negative pressure, thereby forming the reservoir in the micro pump chamber 12. At the same time, the microfluidic liquid can be sucked into the liquid storage chamber under negative pressure via the microfluidic channel 21 and the microvalve chamber 11. In addition, the pressure of the reaction chamber can be controlled to be higher than that of the liquid storage chamber, and the microfluidic liquid can be pushed into the liquid storage chamber through the microfluidic channel 21 and the microvalve chamber 11 by the pressure difference between the reaction chamber and the liquid storage chamber instead of independently changing the pressure of the liquid storage chamber from positive pressure to negative pressure. After the drainage is completed, the micro valve chamber 11 is switched back to positive pressure, and the adjacent unit flow channel 22 is closed, that is, the micro flow channel 21 is closed.

As can be seen, when a positive pressure is input to the micro pump chamber 12 or the micro valve chamber 11, the diaphragm layer 3 is in close contact with the inner surface of the flow control layer 2, and the microfluidic liquid is inhibited from flowing in the microfluidic channel 21. When negative pressure is input into the micro pump chamber 12 or the micro valve chamber 11, the diaphragm layer 3 deforms towards the micro valve chamber 11 or the micro valve chamber 12, and the micro-flow liquid is sucked into a vacuum area between the diaphragm layer 3 and the flow control layer 2, and even can deform to be attached to the wall surface of the inner cavity wall of the micro pump chamber 12 or the micro valve chamber 11 under the limit pressure, so that the micro-flow liquid is filled in the middle of the micro pump chamber 12. The micro-flow liquid flow is indirectly controlled by controlling the deformation of the diaphragm layer 3, the problem that reactants are leaked to the atmosphere can not occur in the control process, and therefore the problem of reactant waste or pollution can not be caused. And the structure of the micro-pump chamber 12 is directly used as a reaction chamber or a liquid storage chamber, so that the number of the micro-valve chambers 11 or the micro-pump chambers 12 in a complex micro-fluidic system can be greatly reduced. The diaphragm layer 3 can reduce the whole pressure of the air hole system and reduce the leakage risk. Therefore, the structure of the pneumatic control chip optimizes the structural redundancy, effectively improves the reliability of the pneumatic control chip and reduces the cost.

Referring to fig. 16 to 22, the micro flow pneumatic chip further includes: and the fixing chamber 23 is arranged on the inner surface of the fluidic layer 2, and the fixing chamber 23 is communicated with the microfluidic channel 21. As shown in fig. 18, the microfluidic pneumatic chip has a micro pump valve and a fixed chamber 23, the fixed chamber 23 is located at the head end of the microfluidic channel 21, the micro pump valve is located at the tail end of the microfluidic channel 21, the vacuum space formed between the diaphragm layer 3 and the fluidic layer 2 can be used as a reaction chamber by deforming the corresponding portion of the diaphragm layer 3 toward the micro pump valve, and the microfluidic liquid is stored in the fixed chamber 23 in advance.

In addition, as shown in fig. 21, the head ends of the plurality of micro flow channels 21 are correspondingly communicated with the same fixed chamber 23, and the plurality of micro pump chambers 12 are correspondingly covered with the tail ends of the plurality of micro flow channels 21. At this time, the micro-flow pneumatic control chip may further be provided with a third air path (not shown) in a matching manner; the third air path is arranged in the air control layer 1 and is opposite to the fixed chamber 23. The fixed chamber 23 located in the middle of the plurality of microfluidic channels 21 may be used for fluid buffering, reagent reaction, etc. to avoid waste and contamination, the fixed chamber 23 may not be communicated with the atmosphere, and therefore, the pressure applied to the membrane layer 3 may be controlled by the pressure output from the third air path, thereby controlling the degree of sealing and isolation of the fixed chamber 23.

In addition, the fixed chamber 23 is located on the flow control layer, the third air path is communicated with the diaphragm layer 3 and is opposite to the fixed chamber 23, and liquid suction or liquid discharge can be realized through pressure exerted on the diaphragm layer 3 by the third air path. For example, in the initial state, positive pressure is applied to the diaphragm layer 3, and the diaphragm layer 3 deforms toward the fixed chamber 23, so that a positive pressure liquid discharge effect is achieved; and negative pressure is applied to the diaphragm layer 3, and the diaphragm layer 3 is restored to be flat, so that the negative pressure liquid absorption effect is realized.

Alternatively, as shown in fig. 22, the head ends of the plurality of microfluidic channels 21 are in one-to-one correspondence with the plurality of fixed chambers 23, and the same one of the micropump chambers 12 is covered with the tail ends of the plurality of microfluidic channels 21. At this time, the fixed chambers 23 located at different ends of the micro pump chamber 12 can be used for sample adding (fluid input) and sampling (fluid output), respectively, and the fixed chambers 23 can be communicated with the atmosphere in this state, which is not described herein again.

Thus, the fixed chamber 23 may store microfluidic liquid instead of the reaction chamber formed by the membrane layer 3. Positive pressure is input into the micro valve chamber 11 and the micro pump chamber 12, at the moment, the diaphragm layer 3 is attached to the inner surface of the flow control layer 2, the diaphragm layer 3 seals the adjacent unit flow channels 22, and simultaneously seals the space between the micro flow channel 21 and the micro pump chamber 12 and the fixed chamber 23, the micro valve chamber 11 is controlled to be in a closed state, and micro flow liquid cannot flow in the micro flow channel 21.

Prior to the experiment, the microfluidic liquid may be stored in the fixed chamber 23, and at this time, the microfluidic liquid cannot flow in the microfluidic channel 21, so as to be ready for the experiment. Similarly, the mode of storing the microfluidic liquid in the fixed chamber 23 in advance may be implemented by forming a relevant infusion path on the microfluidic pneumatic control chip, or by storing the microfluidic liquid in the fixed chamber 23 in advance before the assembly of the pneumatic control layer 1, the diaphragm layer 3, and the fluidic control layer 2, which may be set by a person skilled in the art as required and will not be described herein.

In an experiment, in order to introduce the micro-flow liquid into the reaction chamber from the fixing chamber 23, the positive pressure of the micro-valve chamber 11 can be switched to negative pressure, and at this time, the part of the diaphragm layer 3 corresponding to the micro-valve chamber 11 deforms towards the micro-valve chamber 11 due to the action of the negative pressure, so that the adjacent unit flow channels 22 are communicated, and the micro-flow channels 21 communicated with the adjacent unit flow channels 22 can be used for the micro-flow liquid to flow in the micro-flow channels. At this time, the microfluidic liquid can be introduced from the fixed chamber 23 into the reaction chamber through the microfluidic channel 21 by adjusting the difference in air pressure between the fixed chamber 23 and the reaction chamber. Specifically, as shown in fig. 16 to 18, the input air pressure of the micro pump chamber 12 as the reaction chamber can be controlled to be changed from positive pressure to negative pressure, and the portion of the diaphragm layer 3 corresponding to the micro pump chamber 12 is deformed toward the micro pump chamber 12 by the negative pressure, thereby forming the reaction chamber in the micro pump chamber 12. At the same time, the microfluidic liquid can be sucked into the reaction chamber under negative pressure via the microfluidic channel 21 and the microvalve chamber 11.

In an experiment, in order to guide the micro-flow liquid back to the fixing chamber 23 from the reaction chamber, the positive pressure of the micro-valve chamber 11 can be switched to negative pressure, and at this time, the part of the diaphragm layer 3 corresponding to the micro-valve chamber 11 deforms towards the micro-valve chamber 11 under the action of the negative pressure, so that the adjacent unit flow channels 22 are communicated, and the micro-flow channels 21 communicated with the adjacent unit flow channels 22 can be used for the micro-flow liquid to circulate in the micro-flow channels. By adjusting the pressure difference between the reaction chamber and the fixing chamber 23, the microfluidic liquid can be guided back from the reaction chamber to the fixing chamber 23 through the microfluidic channel 21. Similarly, the pressure of the reaction chamber can be controlled to be higher than that of the fixed chamber 23, and the microfluidic liquid can be pushed into the fixed chamber 23 through the microfluidic channel 21 and the microvalve chamber 11 by the pressure difference between the reaction chamber and the fixed chamber 23. After the drainage is completed, the micro valve chamber 11 is switched back to positive pressure, and the adjacent unit flow channel 22 is closed, that is, the micro flow channel 21 is closed.