Microfluidic chip

Abstract

The present invention discloses a microfluidic chip. The microfluidic chip includes: a chip body, on which a sample extraction unit and fluid pipelines are provided, and the sample extraction unit is used for extracting reactants; a reaction unit, which is adhesively arranged on the chip body, and a reaction area is provided on the reaction unit. The reaction area on the reaction unit is connected to the fluid pipelines on the chip body, and the reactants and reaction reagents can be transported to the reaction area through the fluid pipelines to complete the reaction within the reaction area. The microfluidic chip of the present invention has the characteristics of functional integration, efficient reaction, simple fabrication, and low cost, and can be used for large-scale commercial applications.

Description

Technical Field

[0001] The present invention relates to a biochemical reaction chip, and particularly to a microfluidic chip. Background Art

[0002] Microfluidics technology integrates basic operation units such as sample preparation, reaction, separation, and detection in the processes of biological, chemical, and medical analysis onto a chip at the micron scale, and automatically completes the entire analysis process. Due to its great potential in the fields of biology, chemistry, medicine, etc., it has developed into a brand-new research field that intersects multiple disciplines such as biology, chemistry, medicine, fluid, electronics, materials, and machinery.

[0003] Since the 1990s, biochip technology has always been a research hotspot due to its huge application and market prospects. The US government and the industrial circle have invested nearly $2 billion in total in the research, development, and industrialization of biochips mainly based on gene chips in the past 10 years. The investment intensity in Europe and Japan is also increasing. Motorola, HP, IBM, and Hitachi are all developing gene chip technology. Almost all multinational pharmaceutical companies have invested heavily in using gene chips for ultra-high-throughput screening of new drugs and research on pharmacogenetics, pharmacogenomics, etc. The injection of a large amount of funds has greatly accelerated the development speed of biochip technology. DNA microarray technology has become increasingly mature and gradually shows advantages in various application fields. At the same time, the research on microarray technologies such as protein chips and cell chips is also in the ascendant.

[0004] However, whether it is a DNA microarray or a protein or cell chip, they only complete one step in biochemical analysis - making the obtained biological samples act on the molecules or cells fixed on the chip. For a long time, people have been eager to integrate sample preparation, biochemical reaction, and final result detection into a single system, so as to get rid of the boring labor in experiments. This is what is usually called a Lab-on-a-chip or a Micro Total Analytical System.

[0005] The lab-on-a-chip is the result of the further improvement of gene chip technology and protein chip technology and their expansion into the entire field of biochemical analysis systems. It represents the highest stage of the development of biochip technology. Based on analytical chemistry, relying on microelectromechanical processing technology, characterized by a microchannel network structure, and targeting life science as its main current application, its goal is to integrate the functions of an entire laboratory, including sampling, dilution, reagent addition, reaction, separation, detection, etc., on a microchip, and it can be used multiple times. Therefore, it has a wider range of applicability and application prospects compared to microarrays. It is expected that the technology of biochip micro total analysis systems will be widely applied in aspects such as forensic evidence collection at crime scenes, space exploration, agricultural product quality detection, and environmental detection. Summary of the Invention

[0006] The object of the present invention is to provide a microfluidic chip with integrated functions, efficient reactions, simple fabrication, and low cost.

[0007] To achieve the above object, the specific technical solution of the microfluidic chip of the present invention is as follows:

[0008] A microfluidic chip, which includes: a chip body, on which a sample extraction unit and fluid pipelines are provided, and the sample extraction unit is used for extracting reactants; a reaction unit, which is adhesively disposed on the chip body, and a reaction area is provided on the reaction unit. The reaction area on the reaction unit is connected to the fluid pipelines on the chip body, and reactants and reaction reagents can be transported to the reaction area through the fluid pipelines to complete the reaction within the reaction area.

[0009] Furthermore, the chip body includes a fitting piece unit, a pipeline piece unit, and a control valve piece unit that are stacked. A sample extraction fitting is provided on the fitting piece unit, fluid pipelines are provided on the pipeline piece unit, and control valve components for controlling the on / off of the fluid pipelines are provided on the control valve piece unit.

[0010] Furthermore, after the pipeline piece unit and the fitting piece unit are stacked, a sample extraction area and a waste liquid discharge area are formed. The sample extraction fitting is disposed in the sample extraction area, the waste liquid discharge fitting is disposed in the waste liquid discharge area, and the fluid pipelines on the pipeline piece unit are respectively connected to the sample extraction area and the waste liquid discharge area.

[0011] Furthermore, a pipeline disconnection point is provided on the fluid pipeline of the pipeline piece unit, a pipeline connection hole is provided at the position corresponding to the pipeline disconnection point on the control valve piece unit, the pipeline connection hole is connected to the fluid pipeline near the pipeline disconnection point, and the through - connection of the fluid pipeline on the pipeline piece unit at the pipeline disconnection point is achieved through the pipeline connection hole.

[0012] Further, an opening and closing valve is provided at a position on the control valve sheet unit corresponding to the pipeline connection hole. The opening and closing valve can control the opening and closing of the pipeline connection hole to achieve the connection and disconnection of the corresponding fluid pipeline on the pipeline sheet unit.

[0013] A microfluidic chip, which includes a chip body and a reaction sheet. A sample extraction area, a waste liquid discharge area, and fluid pipelines are provided on the chip body. A reaction area is provided on the reaction sheet. The reaction sheet is attached to the chip body, and the reaction area is connected to the fluid pipelines. The reaction reagent and the reactants extracted from the sample extraction area can be transported to the reaction area through the fluid pipelines to complete the reaction within the reaction area.

[0014] Further, the chip body includes a fitting sheet and a pipeline sheet stacked together. The fitting sheet and the pipeline sheet form a sample extraction area and a waste liquid discharge area in combination. A sample extraction fitting is provided in the sample extraction area, and a waste liquid discharge fitting is provided in the waste liquid discharge area.

[0015] Further, it includes at least two fitting sheets stacked together.

[0016] Further, it includes a top sheet stacked with the fitting sheet. A sample addition port is provided at a position on the top sheet corresponding to the sample extraction fitting.

[0017] Further, fluid pipelines are provided on the pipeline sheet. The fluid pipelines are respectively connected to the sample extraction area, the waste liquid discharge area, and the reaction area on the reaction sheet.

[0018] Further, it includes a valve hole sheet stacked with the pipeline sheet. A pipeline disconnection point is provided on the fluid pipeline of the pipeline sheet. A valve hole is provided at a position on the valve hole sheet corresponding to the pipeline disconnection point. The valve hole on the valve hole sheet is connected to the fluid pipeline near the pipeline disconnection point on the pipeline sheet. The connection of the fluid pipeline on the pipeline sheet at the pipeline disconnection point is achieved through the valve hole.

[0019] Further, a channel sheet is stacked between the pipeline sheet and the valve hole sheet. A group of transition connection holes is provided on the channel sheet. The group of transition connection holes is provided corresponding to the pipeline disconnection point on the pipeline sheet and the valve hole on the valve hole sheet. The group of transition connection holes includes two adjacent connection holes. Each connection hole is respectively connected to the fluid pipelines on both sides of the pipeline disconnection point on the pipeline sheet. The fluid pipeline on the pipeline sheet is connected to the valve hole on the valve hole sheet through the group of transition connection holes on the channel sheet.

[0020] Further, it includes a bottom sheet stacked with the valve hole sheet. The bottom sheet has elasticity. Applying an external force at a position on the bottom sheet corresponding to the valve hole on the valve hole sheet can cause the bottom sheet to deform to block the valve hole on the valve hole sheet, so as to disconnect the connection of the fluid pipeline at the pipeline disconnection point.

[0021] Further, an eluent inlet, a PCR reagent inlet, a hydrophobic exhaust area, a marker inlet, and a reactant outlet are provided on the fluid pipeline. A first fluid pipeline is provided between the sample extraction area and the hydrophobic exhaust area. A second fluid pipeline is provided between the PCR reagent inlet and the hydrophobic exhaust area. A third fluid pipeline is provided between the hydrophobic exhaust area and the reaction area. A fourth fluid pipeline is provided between the reaction area and the reactant outlet. A fifth fluid pipeline is provided between the marker inlet and the reactant outlet. Waste liquid discharge pipelines are provided between the sample extraction area and the waste liquid discharge area, between the reaction area and the waste liquid discharge area, and between the reactant outlet and the waste liquid discharge area.

[0022] Further, there are two third fluid pipelines between the hydrophobic exhaust area and the reaction area.

[0023] Further, a first valve hole is formed on the valve hole sheet corresponding to the first fluid pipeline, a second valve hole is formed corresponding to the third fluid pipeline, a third valve hole is formed corresponding to the fourth fluid pipeline, and a fourth valve hole is formed corresponding to the waste liquid discharge pipeline.

[0024] Further, the reaction sheet and the bottom sheet are stacked. Reaction area connection holes are formed on the valve hole sheet and the bottom sheet. A reactant inlet is formed in the reaction area on the reaction sheet. The reactant inlet is connected to the fluid pipeline through the reaction area connection hole.

[0025] Further, the material of the reaction sheet is polypropylene, and the material of the chip body is polyethylene terephthalate.

[0026] Further, the shape of the reaction area on the reaction sheet is S-shaped.

[0027] Further, a reaction sheet heat dissipation port is provided on the chip body corresponding to the position of the reaction sheet. The reaction sheet is connected to the external environment through the reaction sheet heat dissipation port on the chip body.

[0028] The microfluidic chip of the present invention has the following advantages:

[0029] 1) The reaction unit and the chip body are designed in a split type. On the premise of realizing the integrated function of the microfluidic chip, materials and manufacturing processes can be flexibly selected based on the different functional positions of the reaction unit and the chip body, reducing the overall manufacturing difficulty and cost of the microfluidic chip and improving the use effect of the microfluidic chip.

[0030] 2) The chip body with a multi-layer stacked design reduces the processing difficulty, can be manufactured standardly, and is convenient for batch production and assembly of the microfluidic chip.

[0031] 3) The fluid pipeline and control valve with a hierarchical design achieve refined control of the flow of reaction fluid on the microfluidic chip, ensuring the smooth progress of the reaction on the microfluidic chip.

[0032] 4) Only the extraction and amplification steps are integrated on the microfluidic chip. While achieving the effect of integration, it can also ensure good usage effects and facilitate commercial applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic structural diagram of a specific example of the microfluidic chip of the present invention;

[0034] Figure 2 is Figure 1 the schematic structural diagram of the microfluidic chip in after removing the additional components;

[0035] Figure 3 is Figure 1 the perspective view of the pipeline of the microfluidic chip in ;

[0036] Figure 4 is Figure 3 the partial enlarged view of the pipeline connection in ;

[0037] Figure 5 is Figure 1 the exploded view of the microfluidic chip in ;

[0038] Figure 6 is Figure 5 the schematic structural diagram of the top sheet in ;

[0039] Figure 7 is Figure 5 the schematic structural diagram of the accessory sheet in ;

[0040] Figure 8 is Figure 5 the schematic structural diagram of the pipeline sheet in ;

[0041] Figure 9 is Figure 5 the schematic structural diagram of the channel sheet in ;

[0042] Figure 10 is Figure 5 the schematic structural diagram of the valve hole sheet in ;

[0043] Figure 11 is Figure 5 the schematic structural diagram of the bottom sheet in ;

[0044] Figure 12 is Figure 5 the schematic structural diagram of the reaction sheet in . DETAILED DESCRIPTION OF THE EMBODIMENTS

[0045] In order to better understand the purpose, structure and function of the present invention, the following further describes a microfluidic chip of the present invention in detail with reference to the accompanying drawings.

[0046] In theory, a microfluidic chip can integrate multiple basic operation units such as sample preparation, reaction, separation, and detection in the processes of biology, chemistry, and medical analysis. However, due to the limitations of technological development, integrating too many operation steps on a single microfluidic chip will instead reduce the accuracy and precision of experimental results, and significantly degrade the overall performance of the chip. Therefore, it can only be used in laboratory research and cannot be applied commercially on a large scale. The microfluidic chip in this invention only integrates the sample extraction and reaction operation units. On the premise of achieving miniaturization and integration, it can ensure good performance and can be widely used in various commercial instruments, such as DNA integrated detectors, PCR amplifiers, etc.

[0047] Compared with the existing integrated microfluidic chips, the microfluidic chip in this invention consists of two parts: one is the chip body, and the other is the reaction unit. Among them, the chip body is the main part of the microfluidic chip, which can integrate sample extraction, fluid pipelines, reaction reagents, etc.; the reaction unit is a dedicated reaction area for implementing the reaction steps. In this invention, the chip body and the reaction unit are two independently designed components, and their materials and shapes can be flexibly designed according to needs. Combining the formed chip body and reaction unit together constitutes the microfluidic chip of this invention.

[0048] This design is based on the consideration that most biochemical reactions have special requirements for the materials and shapes of reaction vessels, and these special materials may not be suitable for mass-producing the chip body, or special shapes may not be convenient to fabricate on a conventional chip body. For example, there may be problems such as high processing difficulty, high material cost, and poor performance. Taking the PCR reaction as an example, using a reaction vessel made of PP material (polypropylene) can significantly improve the reaction effect. However, compared with conventional chip materials, PP material has problems such as high processing difficulty and high material cost, and is not suitable for application to the entire microfluidic chip. The microfluidic chip of this invention solves this problem well by designing the chip body and the reaction unit separately, and only using PP material to make the reaction unit, which significantly improves the performance of the microfluidic chip.

[0049] [[ID=⑨]]In addition, the separate design of the reaction unit can also make the shape of the reaction area more flexible without considering the processing complexity of the chip body, because many auxiliary structures such as fluid pipelines inevitably need to be designed on the chip body. Still taking the PCR reaction as an example, through experimental verification, an S-shaped reaction area can significantly improve the reaction effect. If such a reaction area is fabricated on the chip body, not only the problem of the chip processing mold needs to be solved, but also the problem of sealing the reaction area needs to be solved, which increases the overall processing difficulty of the chip. In this invention, however, this reaction shape can be conveniently fabricated on the reaction unit because there are almost no additional auxiliary structures on the reaction unit, greatly reducing the complexity of the manufacturing process.

[0050] Meanwhile, the independently designed reaction unit also facilitates precise temperature control because the reactions in the microfluidic chip have more stringent temperature requirements, while the existing reaction units integrated on the chip body are not ideal in terms of temperature control. In this invention, an independent reaction unit is adopted, and a temperature control device can be flexibly designed for this reaction unit, and the contact between the temperature control device and the reaction unit is made more convenient, greatly improving the temperature control effect of the reaction unit.

[0051] Regarding the chip body of this invention, to further reduce the manufacturing difficulty, the chip body can be composed of multiple groups of sheet units stacked together. For example, it can be composed of a top sheet unit, a fitting sheet unit, a pipe sheet unit, a channel sheet unit, a valve hole sheet unit, and a bottom sheet unit stacked and combined in sequence. Thus, the complex structure of the chip body can be decomposed and realized by different sheet units. For example, the installation spaces of each fitting unit are made on the top sheet unit and the fitting sheet unit, the basic fluid pipelines are made on the pipe sheet unit and the channel sheet unit, and the fluid pipeline control valves are made on the valve hole sheet unit and the bottom sheet unit, facilitating the standardized and batch production in the factory. Stacking and processing the batch-produced sheet units together can complete the manufacturing of the chip with a complex structure. There are various ways to stack and process the sheet units, such as bonding, keying, etc.

[0052] The chip body in this invention mainly integrates a sample extraction unit, a fluid pipeline unit, and a waste liquid discharge unit. Of course, according to needs, a reagent storage unit can also be integrated on the chip body. Among them, the sample extraction unit can complete the extraction of the sample, the fluid pipeline unit can realize the flow of the reaction fluid on the chip body, the waste liquid discharge unit can absorb the excess reaction fluid on the chip body, and the reagent storage unit can pre-store the required reagents according to needs. It should be noted that the reagent storage unit is not a necessary unit on the chip body, and an external reagent container can also be used as an alternative.

[0053] Taking DNA extraction as an example, the sample extraction unit can adopt various extraction methods, such as extraction using FTA paper. As a patented technology of Whatman, FTA paper is uniquely applied to the collection, transportation, purification, and storage of DNA and RNA at room temperature. All operations are completed on a single card, making it very suitable for application on miniaturized and integrated microfluidic chips. Additionally, the existing magnetic bead extraction method can also be used. Magnetic bead nucleic acid extraction is a new type of nucleic acid extraction technology with nano-bio magnetic beads as the carrier. Nucleic acid molecules can specifically recognize and bind to the silanol groups on the surface of the magnetic beads, and aggregate or disperse under the action of an external magnetic field, completely getting rid of the manual operation processes such as centrifugation and supernatant extraction in the traditional nucleic acid extraction process, thereby realizing the automated extraction of nucleic acids. Thus, the sample extraction unit on the microfluidic chip of the present invention can adopt any method capable of automatically extracting samples to meet the requirements of integration and automation.

[0054] The fluid pipeline unit is mainly used to connect the various component units on the microfluidic chip to enable the flow of samples and reagents between the component units. For the fluid pipeline unit, it mainly includes two aspects. One is the driving of the fluid, that is, how to drive the samples and reagents to flow in the fluid pipeline, and the other is the control of the fluid, that is, how to control the flow direction of the samples and reagents in the fluid pipeline.

[0055] In the microfluidic chip of the present invention, a micro pump is mainly used to achieve the driving of the fluid. Among them, the micro pump can adopt mechanical micro pumps, such as centrifugal force micro pumps, thermo-dynamic micro pumps, electrostatic micro pumps, pneumatic micro pumps, electromagnetic micro pumps, piezoelectric micro pumps, bimetallic memory alloy micro pumps, etc. Mechanical micro pumps can provide low-flow fluid transportation matching the fluid channels on the microfluidic chip, and are particularly suitable for the simple interface assembly of polymer material chips. Of course, according to the actual situation, non-mechanical micro pumps can also be used to achieve the driving of the flow on the microfluidic chip, such as electric field force-driven pumps, capillary action micro pumps, biological action micro pumps, magneto-hydrodynamic pumps, light-driven pumps, gravity-driven pumps, chemical action micro pumps, etc.

[0056] For the control of the fluid flow on the microfluidic chip, in the present invention, it is achieved through the special design of the fluid pipeline and the micro valve structure used in cooperation. Among them, multiple fluid pipelines are provided on the chip body, and each fluid pipeline will be connected to a certain operation or reaction area on the microfluidic chip so that the fluid reagent can flow to the operation or reaction area through this fluid pipeline. The fluid connection between two operation or reaction areas requires the corresponding fluid pipelines to be fluid-connected first. On the chip body of the present invention, a flow connection hole is provided between two corresponding fluid pipelines, and opening or closing this flow connection hole can achieve the connection or disconnection of the two fluid pipelines.

[0057] The opening or closing of the flow connection holes can be achieved in various ways. For example, an elastic structure layer is provided on one side of the flow connection holes. By applying an external force to the position corresponding to a certain flow connection hole on the elastic structure layer, the elastic structure layer can seal the flow connection hole, achieving the closing of the flow connection hole. Correspondingly, the two fluid pipelines are in a disconnected state at the flow connection hole, and the fluid reagent cannot flow between the two fluid pipelines. When the external force is removed, the elastic structure layer can automatically reset, opening the flow connection hole. Correspondingly, the two fluid pipelines will be in a connected state through the flow connection hole, and the fluid reagent can flow between the two fluid pipelines. Among them, the external force applied to the elastic structure layer can be realized by a solenoid valve, a pneumatic piston, etc.

[0058] Therefore, in the microfluidic chip of the present invention, the reaction unit and the chip body are designed separately. On the premise of realizing the integrated functions of the microfluidic chip, materials and manufacturing processes can be flexibly selected based on the different functional positions of the reaction unit and the chip body, reducing the overall manufacturing difficulty and cost of the microfluidic chip and improving the use effect of the microfluidic chip. At the same time, the chip body with a multi-layer laminated design reduces the processing difficulty, can be manufactured standardly, facilitating the batch production and assembly of the microfluidic chip, and the fluid pipelines and control valves with a hierarchical design achieve the refined control of the flow of the reaction fluid on the microfluidic chip, ensuring the smooth progress of the reaction on the microfluidic chip.

[0059] The following Figures 1 to 12 will describe a preferred embodiment of the microfluidic chip of the present invention in conjunction with the attached

[0060] As Figures 1 to 3 shown, in this embodiment, the microfluidic chip mainly integrates two steps of DNA extraction and PCR amplification, and can be applied to DNA integrated detection equipment. Subsequent steps such as electrophoresis separation are realized by other equipment. It should be noted that in this embodiment, the reagents are not integrated onto the microfluidic chip but are connected to an external reagent kit.

[0061] As Figure 5 shown, the microfluidic chip includes a top sheet 1, a fitting sheet 2, a pipeline sheet 3, a channel sheet 4, a valve hole sheet 5, a bottom sheet 6, and a reaction sheet 7 that are sequentially stacked. Among them, the top sheet 1, the fitting sheet 2, the pipeline sheet 3, the channel sheet 4, the valve hole sheet 5, and the bottom sheet 6 have the same size and shape, and are laminated to form the chip body. The chip body is the bearing component of the microfluidic chip, and a sample extraction area 8, fluid pipelines 9, and a waste liquid discharge area 10 are integrated on the chip body; the reaction sheet 7 is attached to the chip body and is the reaction component of the microfluidic chip. A reaction area 11 is formed on the reaction sheet, and the reaction area 11 on the reaction sheet 7 is connected to the fluid pipelines 9 on the chip body.

[0062] Among them, it is preferred that the materials of the top plate 1, accessory plate 2, pipe plate 3, channel plate 4, valve hole plate 5 and bottom plate 6 that constitute the chip body are PET material (polyethylene terephthalate). Among them, PET material has excellent physical and mechanical properties in a wide temperature range, and the long-term use temperature can reach 120°C. It has excellent electrical insulation properties, and even under high temperature and high frequency, its electrical properties are still good. It has good creep resistance, fatigue resistance, friction resistance and dimensional stability. It is very suitable as the main material of the chip and has the advantages of easy processing and low price.

[0063] Preferably, the reaction chip 7 is made of PP (polypropylene). PP has a low density and superior strength, stiffness, hardness, and heat resistance to low-pressure polyethylene. It can be used up to approximately 150°C, exhibits excellent dielectric properties and high-frequency insulation, and is unaffected by humidity. However, it becomes brittle at low temperatures, is not wear-resistant, and is susceptible to aging. PP is difficult to process and is not suitable for use as the main material for the chip. However, for PCR reactions, using PP as a reaction vessel significantly improves reaction efficiency. Therefore, in this embodiment, the reaction chip 7 is made of PP.

[0064] Specifically, if Figure 5 and Figure 6 As shown, the top sheet 1 is the upper encapsulation sheet of the microfluidic chip, primarily serving to seal the chip body. Corresponding to the internal structure of the microfluidic chip in this embodiment, the top sheet 1 is formed with a sample addition port 12, a hydrophobic vent 13, a heat dissipation port 14 for the reaction chip, a reagent addition port 15, and a reactant delivery port 16.

[0065] The sample addition port 12 is connected to the sample extraction area 8 on the chip body. The sample to be processed can be added to the chip through the sample addition port 12. A sealing cover 17 is provided at the sample addition port 12; the hydrophobic exhaust port 13 is connected to the hydrophobic exhaust area 18 on the fluid pipeline 9 in the chip body. The hydrophobic exhaust port 13 is provided with a hydrophobic exhaust accessory 19 for exhausting the fluid pipeline 9; the reaction plate heat dissipation port 14 is connected to the reaction plate 7 attached to the chip body, and is used to connect the reaction plate 7 with the external environment to facilitate heat dissipation; the reagent addition port 15 is connected to the reagent inlet on the fluid pipeline 9 in the chip body, and is used to add reaction reagents to the fluid pipeline 9. There are multiple reagent addition ports 15, each reagent addition port 15 corresponds to a reagent; a connecting conduit 20 is provided at the reactant delivery port 16, and the reactant delivery port 16 can be connected to subsequent reaction equipment through the connecting conduit 20, such as a capillary, for delivering the reactants on the microfluidic chip to the subsequent equipment.

[0066] like Figure 5 andFigure 7 As shown, the accessory sheet 2 is located below the top sheet 1 and is used to provide installation space for various accessories on the microfluidic chip, such as sample extraction accessories, waste liquid discharge accessories, etc. Among them, considering the processing difficulty, the thickness of the accessory sheet 2 should not be too large. Therefore, in order to ensure that each accessory has sufficient installation space, the number of accessory sheets 2 can be multiple, such as two, three, etc. As Figure 5 shown, in this embodiment, two accessory sheets 2 are provided.

[0067] Corresponding to the internal structure of the microfluidic chip in this embodiment and the structure of the above-mentioned top sheet 1, a sample extraction accessory installation area 21, a hydrophobic exhaust port 13, a reaction sheet heat dissipation port 14, a reagent addition port 15, a reactant delivery port 16, and a waste liquid discharge accessory installation area 22 are formed on the accessory sheet 2. Among them, the sample extraction accessory installation area 21 corresponds to the sample addition port 12 on the top sheet 1 and is used to hold the sample extraction accessory; the waste liquid discharge accessory installation area 22 is used to hold the waste liquid discharge accessory.

[0068] It should be noted that in this embodiment, the sample extraction accessory preferably uses an FTA test paper. As a patented technology of Whatman Company, the FTA test paper is uniquely applied to the collection, transportation, purification and storage of DNA and RNA at room temperature, and all work is completed on one card. Of course, the sample extraction accessory can also use a similar magnetic bead method extraction component, etc., as long as it can achieve sample extraction. In addition, the waste liquid discharge accessory preferably uses a paper with fluid absorption function, etc., for convenient installation.

[0069] As Figure 5 and Figure 8 shown, the pipeline sheet 3 is located below the accessory sheet 2 and is a carrier sheet for the fluid pipeline 9. The fluid reagent mainly flows in the fluid pipeline 9 on the pipeline sheet 3 to achieve flow between each functional area. At the same time, the pipeline sheet 3 and the accessory sheet 2 also provide installation space for each accessory to facilitate the connection of each accessory to the fluid pipeline 9.

[0070] Corresponding to the internal structure of the microfluidic chip in this embodiment and the structure of the above-mentioned accessory sheet 2, a fluid pipeline 9, a sample extraction accessory installation area 21, a reaction sheet heat dissipation port 14, and a waste liquid discharge accessory installation area 22 are formed on the pipeline sheet 3. Among them, the sample extraction accessory installation area 21 on the accessory sheet 2 and the pipeline sheet 3 and the sample extraction accessory together form the sample extraction area 8; the waste liquid discharge accessory installation area 22 on the accessory sheet 2 and the pipeline sheet 3 and the waste liquid discharge accessory together form the waste liquid discharge area 10; a reagent inlet, a hydrophobic exhaust area 18, and a reactant outlet 23 are provided on the fluid pipeline 9, and the fluid pipeline 9 can connect each functional area to facilitate the flow of reaction fluid between each functional area.

[0071] Corresponding to the DNA extraction and PCR amplification operations integrated on the microfluidic chip, the reagent inlets on the fluid conduit 9 include an eluent inlet 30 and a PCR reagent inlet 31. Corresponding to the subsequent electrophoresis and detection operations, the reagent inlets on the fluid conduit 9 may also include a marker inlet 32. The eluent inlet 30 on the fluid conduit 9 is connected to the sample extraction area 8, allowing the eluent inputted from the eluent inlet 30 to flush out the reactants extracted from the sample extraction area 8. The PCR reagent inlet 31 is connected to the reaction area 11 on the reaction chip 7. The PCR reagent inputted from the PCR reagent inlet 31 can flow into the reaction area 11 on the reaction chip 7 together with the reactants flushed from the sample extraction area 8 to perform the PCR reaction. The marker inlet 32 is connected to the reactant outlet 23 on the fluid conduit 9. The marker can be inputted through the marker inlet 32 and then transported along the fluid conduit 9 to the reactant outlet 23. Thereafter, the marker can be transported via the reactant outlet 23, the reactant delivery port 16, and the connecting conduit 20 to the subsequent reaction equipment.

[0072] like Figure 3 and Figure 8 As shown, in this embodiment, the fluid conduits 9 on the duct sheet 3 include: a first fluid conduit 33 connecting the sample extraction area 8 and the hydrophobic venting area 18; a second fluid conduit 34 connecting the PCR reagent inlet 31 and the hydrophobic venting area 18; a third fluid conduit 35 connecting the hydrophobic venting area 18 and the reaction area 11; a fourth fluid conduit 36 connecting the reaction area 11 and the reactant outlet 23; a fifth fluid conduit 37 connecting the marker inlet 32 and the reactant outlet 23; and a waste liquid discharge conduit 38 connecting the sample extraction area 8 and the waste liquid discharge area 10, the reaction area 11 and the waste liquid discharge area 10, and the reactant outlet 23 and the waste liquid discharge area 10. Preferably, there are two third fluid conduits 35 connecting the hydrophobic venting area 18 and the reaction area 11 to facilitate sufficient filling of the reaction area 11 with the reactants.

[0073] In this embodiment, Figure 8 As shown, the fluid pipeline 9 between any two functional areas on the pipeline sheet 3 is not through-connected, but disconnected, that is, a pipeline disconnection point 24 is formed on the fluid pipeline 9. The fluid cannot flow directly between the functional areas through the fluid pipeline 9 on the pipeline sheet 3, but must rely on the channel sheet 4 and valve hole sheet 5 described below to facilitate precise control of the flow of fluid on the microfluidic chip.

[0074] like Figure 5 and Figure 9As shown, the channel sheet 4 is located below the duct sheet 3 to provide a transition connection for the fluid pipelines 9 on the duct sheet 3, thereby achieving precise control of the fluid flow within the microfluidic chip. Corresponding to the internal structure of the microfluidic chip in this embodiment and the structure of the duct sheet 3 described above, the channel sheet 4 is formed with a transition connection hole group 25, reaction area connection holes 26, and reaction plate heat dissipation vents 14.

[0075] Among them, the transition connection hole group 25 is set corresponding to the pipeline disconnection point 24 of the fluid pipeline 9 on the pipeline plate 3, and each transition connection hole group 25 includes two adjacent connection holes, each connection hole is respectively connected to the fluid pipelines on both sides of the pipeline disconnection point 24 on the fluid pipeline 9; the reaction area connection hole 26 is connected to the reaction area 11 on the reaction plate 7, and is used to transport the reaction fluid to the reaction area 11 on the reaction plate 7.

[0076] like Figure 5 and Figure 10 As shown, the valve hole plate 5 is located below the channel plate 4 and is used to connect the fluid pipeline 9 on the pipeline plate 3. Corresponding to the internal structure of the microfluidic chip in this embodiment and the structures of the pipeline plate 3 and channel plate 4 described above, the valve hole plate 5 is formed with a valve hole 27, a reaction area connection hole 26, and a reaction plate heat dissipation vent 14.

[0077] The valve holes 27 are provided corresponding to the transition hole groups 25 on the channel plate 4. Each transition hole group 25 is connected to a valve hole 27. That is, two adjacent connection holes in the transition hole group 25 are connected to the valve holes 27 respectively. Thus, the fluid pipeline 9 can be connected at the pipeline disconnection point 24 through the transition hole group 25 and the valve hole 27. For specific connection methods, please refer to Figure 4 .

[0078] Specifically, a first valve hole 40 is formed corresponding to the first fluid pipeline 33 connecting the sample extraction area 8 and the hydrophobic exhaust area 18; a second valve hole 41 is formed corresponding to the third fluid pipeline 35 connecting the hydrophobic exhaust area 18 and the reaction area 11; a third valve hole 42 is formed corresponding to the fourth fluid pipeline 36 connecting the reaction area 11 and the reactant outlet 23; and a fourth valve hole 43 is formed corresponding to the waste liquid discharge pipeline 38 connecting the sample extraction area 8 and the waste liquid discharge area 10, the reaction area 11 and the waste liquid discharge area 10, and the reactant outlet 23 and the waste liquid discharge area 10.

[0079] like Figure 5 and Figure 11 As shown, the bottom plate 6 is located below the valve plate 5 and serves as the lower packaging plate of the microfluidic chip. Corresponding to the internal structure of the microfluidic chip in this embodiment and the structure of the valve plate 5 described above, the bottom plate 6 is formed with reaction area connection holes 26 and reaction plate heat dissipation vents 14.

[0080] Meanwhile, in order to control the opening and closing of the valve holes 27 on the valve hole sheet 5, the bottom sheet 6 is preferably elastic. Thus, by applying an external force to the position on the bottom sheet 6 corresponding to the valve holes 27 on the valve hole sheet 5, the bottom sheet 6 can be deformed, and then the bottom sheet 6 can block the valve holes 27 on the valve hole sheet 5, causing the fluid pipeline 9 to be continuously disconnected at the pipeline disconnection point 24. It should be noted that the external force applied to the bottom sheet 6 can be applied by a microfluidic control system used in conjunction with the microfluidic chip. For example, a solenoid valve is provided in the microfluidic control system corresponding to the valve holes 27 on the valve hole sheet 5, and the opening and closing of the valve holes 27 can be achieved by the lifting of the solenoid valve. The specific structure of the microfluidic control system has been claimed in another patent application.

[0081] As Figure 5 and Figure 12 shown, the reaction sheet 7 is located below the bottom sheet 6 and is a dedicated reaction vessel, and its size and shape can be flexibly set according to different situations. In addition, a protective gasket 39 can be provided between the reaction sheet 7 and the bottom sheet 6. Corresponding to the internal structure of the microfluidic chip in this embodiment and the structure of the above chip body, a reaction area 11, a reactant inlet 28, and a reactant outlet 29 are formed on the reaction sheet 7.

[0082] Among them, in order to improve the effect of the PCR reaction, the shape of the reaction area 11 on the reaction sheet 7 is preferably S-shaped. The S-shaped reaction area 11 is connected to the corresponding reaction area connection hole 26 on the chip body through the reactant inlet 28. Thus, the reactants can flow into the reaction area 11 through the fluid pipeline 9, the reaction area connection hole 26, and the reactant inlet 28 to carry out the PCR reaction. The reaction products can be transported to the reactant outlet 23 through the reactant outlet 29, the corresponding reaction area connection hole 26 on the chip body, and the fluid pipeline 9, and then transported to the subsequent reaction equipment through the reactant transport port 16 and the connection conduit 20.

[0083] Combined with Figure 3 shown, the working process of the microfluidic chip of the present invention is as follows:

[0084] First, an external force is applied to the corresponding area on the bottom sheet 6 to close all the valve holes 27 on the valve hole sheet 5, causing the corresponding fluid pipelines 9 on the channel sheet 3 to be in a disconnected state.

[0085] Secondly, the test sample is added to the sample extraction fitting in the sample extraction area 8 through the sample addition port 12 on the top sheet 1.

[0086] Next, open the first valve hole 40 on the valve hole sheet 5 to make the first fluid pipeline 33 between the sample extraction area 8 and the hydrophobic exhaust area 18 in a through state. At the same time, introduce the eluent from the eluent inlet 30, and the DNA can be eluted from the sample extraction fitting in the sample extraction area 8 and flow to the hydrophobic exhaust area 18.

[0087] Next, close the first valve hole 40 on the valve hole sheet 5 and open the second valve hole 41 to make the third fluid pipeline 35 between the hydrophobic exhaust area 18 and the reaction area 11 in a through state. The DNA and the PCR reagent enter the reaction area 11 on the reaction sheet 7 through the third fluid pipeline 35.

[0088] Next, close the second valve hole 41 on the valve hole sheet 5 to make the reaction area 11 on the reaction sheet 7 an isolated chamber for PCR reaction.

[0089] Finally, after the PCR reaction is completed, open the third valve hole 42 to make the fourth fluid pipeline 36 between the reaction area 11 and the reactant outlet 23 in a through state. The reactants in the reaction area 11 can flow to the reactant outlet 23. At the same time, introduce the marker from the marker inlet 32. Therefore, the amplified DNA and the marker can enter the subsequent capillary for electrophoresis separation operation.

[0090] Among them, during the whole process, if there is too much waste liquid, the fourth valve hole 43 can be selectively opened to make the waste liquid discharge pipelines 38 between the sample extraction area 8 and the waste liquid discharge area 10, the reaction area 11 and the waste liquid discharge area 10, and the reactant outlet 23 and the waste liquid discharge area 10 selectively through, so that the excess fluid enters the waste liquid discharge area 10.

[0091] The above further describes the present invention with specific embodiments. However, it should be understood that the specific description here should not be construed as a limitation on the essence and scope of the present invention. Various modifications made by those of ordinary skill in the art after reading the above embodiments belong to the scope protected by the present invention.

Claims

1. A microfluidic chip, characterized in that: include: The chip body and the reaction unit are two independent separate components. After molding, the chip body and the reaction unit are combined to form a microfluidic chip. The chip body is provided with a sample extraction unit and a fluid pipeline. The sample extraction unit is used to extract reactants. The chip body is composed of a top plate unit, an accessory plate unit, a pipeline plate unit, a channel plate unit, a valve hole plate unit, and a bottom plate unit stacked in sequence. The accessory plate unit is provided with sample extraction accessories, the pipeline plate unit is provided with a fluid pipeline, and the control valve plate unit is provided with a control valve component that controls the on-off of the fluid pipeline. A pipeline disconnection point is provided on the fluid pipeline of the pipeline plate unit, and a pipeline connection hole is provided at a position corresponding to the pipeline disconnection point on the control valve plate unit. The pipeline connection hole is connected to the fluid pipeline near the pipeline disconnection point. The fluid pipeline on the pipeline plate unit is connected at the pipeline disconnection point through the pipeline connection hole. The reaction unit is attached to the chip body, and a reaction area is provided on the reaction unit. The reaction area on the reaction unit is connected to the fluid pipeline on the chip body. The reactants and reaction reagents can be transported to the reaction area through the fluid pipeline to complete the reaction in the reaction area.

2. The microfluidic chip according to claim 1, characterized in that When the pipeline sheet unit and the accessory sheet unit are overlapped, a sample extraction area and a waste liquid discharge area are formed. The sample extraction accessories are arranged in the sample extraction area, and the waste liquid discharge accessories are arranged in the waste liquid discharge area. The fluid pipelines on the pipeline sheet unit are respectively connected to the sample extraction area and the waste liquid discharge area.

3. The microfluidic chip according to claim 1, characterized in that An on-off valve is provided at the position corresponding to the pipeline connection hole on the control valve plate unit. The on-off valve can control the opening and closing of the pipeline connection hole to realize the connection and disconnection of the corresponding fluid pipeline on the pipeline plate unit.

4. A microfluidic chip, characterized in that: The device comprises a top plate, an accessory plate, a pipeline plate, a channel plate, a valve hole plate, a bottom plate and a reaction plate stacked in sequence. The accessory plate and the pipeline plate are combined to form a sample extraction area and a waste liquid discharge area. The sample extraction area is provided with a sample extraction accessory, and the waste liquid discharge area is provided with a waste liquid discharge accessory. The pipeline sheet is provided with a fluid pipeline, which is respectively connected to the sample extraction area, the waste liquid discharge area and the reaction area on the reaction sheet. The fluid pipeline of the pipeline sheet is provided with a pipeline disconnection point. The valve hole sheet is provided with a valve hole at a position corresponding to the pipeline disconnection point. The valve hole on the valve hole sheet is connected to the fluid pipeline near the pipeline disconnection point on the pipeline sheet. The fluid pipeline on the pipeline sheet is connected at the pipeline disconnection point through the valve hole. The channel sheet is formed with a reaction area connection hole, and the reaction sheet is formed with a reaction area, a reactant inlet, and a reactant outlet. The reaction area on the reaction sheet is connected to the corresponding reaction area connection hole on the chip body through the reactant inlet. The reactant flows into the reaction area through the fluid pipeline, the reaction area connection hole, and the reactant inlet. The reaction product can be transported to the corresponding reaction area connection hole on the chip body through the reactant outlet on the reaction sheet. The chip body is provided with a sample extraction area, a waste liquid discharge area and a fluid pipeline, and the reaction area is provided on the reaction chip. The reaction chip is attached to the chip body, and the reaction area is connected to the fluid pipeline. The reaction reagents and reactants extracted from the sample extraction area can be transported to the reaction area through the fluid pipeline to complete the reaction in the reaction area.

5. The microfluidic chip according to claim 4, characterized in that: It comprises at least two accessory pieces, and the at least two accessory pieces are overlapped.

6. The microfluidic chip according to claim 4, characterized in that: It comprises a top sheet overlapped with the accessory sheet, and a sample adding port is arranged on the top sheet at a position corresponding to the sample extraction accessory.

7. The microfluidic chip according to claim 4, characterized in that: A channel sheet is overlapped between the pipeline sheet and the valve hole sheet, and a transition connection hole group is provided on the channel sheet. The transition connection hole group corresponds to the pipeline disconnection point on the pipeline sheet and the valve hole on the valve hole sheet. The transition connection hole group includes two adjacent connection holes, each connection hole is respectively connected to the fluid pipelines on both sides of the pipeline disconnection point on the pipeline sheet, and the fluid pipeline on the pipeline sheet is connected to the valve hole on the valve hole sheet through the transition connection hole group on the channel sheet.

8. The microfluidic chip according to claim 4, characterized in that: It includes a bottom plate overlapped with the valve hole plate. The bottom plate is elastic. When external force is applied to the bottom plate at a position corresponding to the valve hole on the valve hole plate, the bottom plate can be deformed to block the valve hole on the valve hole plate, so that the fluid pipeline is disconnected at the pipeline disconnection point.

9. The microfluidic chip according to claim 8, characterized in that: The fluid pipeline is provided with an eluent inlet, a PCR reagent inlet, a hydrophobic exhaust area, a marker inlet and a reactant outlet; a first fluid pipeline is provided between the sample extraction area and the hydrophobic exhaust area, a second fluid pipeline is provided between the PCR reagent inlet and the hydrophobic exhaust area, a third fluid pipeline is provided between the hydrophobic exhaust area and the reaction area, a fourth fluid pipeline is provided between the reaction area and the reactant outlet, a fifth fluid pipeline is provided between the marker inlet and the reactant outlet, and a waste liquid discharge pipeline is provided between the sample extraction area and the waste liquid discharge area, the reaction area and the waste liquid discharge area, and the reactant outlet and the waste liquid discharge area.

10. The microfluidic chip according to claim 9, characterized in that: There are two third fluid pipelines between the hydrophobic exhaust area and the reaction area.

11. The microfluidic chip according to claim 9, characterized in that: The valve hole plate is formed with a first valve hole corresponding to the first fluid pipeline, a second valve hole corresponding to the third fluid pipeline, a third valve hole corresponding to the fourth fluid pipeline, and a fourth valve hole corresponding to the waste liquid discharge pipeline.

12. The microfluidic chip according to claim 4 or 8, characterized in that: The material of the reaction piece is polypropylene, and the material of the chip body is polyethylene terephthalate.

13. The microfluidic chip according to claim 4 or 8, characterized in that: The reaction area on the reaction sheet has an S-shaped shape.

14. The microfluidic chip according to claim 4 or 8, characterized in that: A reaction plate heat dissipation port is provided at a position on the chip body corresponding to the reaction plate, and the reaction plate is connected to the external environment through the reaction plate heat dissipation port on the chip body.

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