WO2024078548A1

WO2024078548A1 - Microfluidic chip and method for using same, microfluidic system and method for manufacturing conductive cover board

Info

Publication number: WO2024078548A1
Application number: PCT/CN2023/124095
Authority: WO
Inventors: 陈天蓝; 刘成海; 吴峥; 邬祥俊; 梁美贤; 成可璇
Original assignee: 珠海市迪奇孚瑞生物科技有限公司
Priority date: 2022-10-12
Filing date: 2023-10-11
Publication date: 2024-04-18

Abstract

A microfluidic chip (304) and a method for using the same, a microfluidic system, and a method for manufacturing a conductive cover board (4). The chip (304) comprises an extraction assembly (1) and an amplification assembly (2), wherein the extraction assembly (1) comprises a lysis chamber (100), a first valve chamber (101), a cleaning chamber (102, 103) and a second valve chamber (104) that are connected in sequence; the amplification assembly (2) comprises a chip substrate (6), a barrier layer (5) and a conductive cover board (4); the barrier layer (5) is located between the chip substrate (6) and the conductive cover board (4), and the barrier layer (5), the chip substrate (6) and the conductive cover board (4) enclose an elution chamber (21), a liquid path chamber (22), and an amplification chamber (23) that are connected in sequence, and the elution chamber (21) is in communication with the second valve chamber (104) via a first passage (24); an electrode array (7) is provided on the chip substrate (6); the conductive cover board (4) is provided with a bottom-opening cavity (400) on a side adjacent to the chip substrate (6), and the elution chamber (21) comprises the cavity (400); the electrode array (7) is located directly below the elution chamber (21), the liquid path chamber (22), and the amplification chamber (23); the amplification assembly (2) further comprises a storage chamber (20) for storing surfactant, and the storage chamber (20) is in communication with the elution chamber (21) via a second passage (25); and the liquid path chamber (22) comprises a liquid storage cavity (220), and the liquid storage chamber (220) is adjacent to the elution chamber (21); and the thickness of the chamber (400) is in a range from 0.6 mm to 2 mm in the thickness direction of the microfluidic chip (304).

Description

Microfluidic chip and method of using the same, microfluidic system and method of manufacturing a conductive cover plate

Technical Field

The present invention relates to the field of microfluidic technology, and in particular to a microfluidic chip and a method for using the same, a microfluidic system, and a method for manufacturing a conductive cover. This application is based on a Chinese invention patent application with an application date of October 12, 2022 and an application number of CN202211247595.1 and an application date of July 11, 2023 and an application number of CN202310848619.7, and a Chinese utility model patent application with an application date of October 12, 2022 and an application number of CN202222690774.4, and the contents of the above applications are incorporated herein by reference.

Background technique

Digital microfluidics (DMF) is a branch of microfluidics that can control single droplets from microliter to nanoliter in size. Digital microfluidics based on electrowetting-ondielectric (EWOD) can process single droplets on an electrode array through electrowetting forces. Its electrical drive function and small footprint make it a promising technology for point-of-care diagnosis.

There are two types of PCR methods on digital microfluidic systems: stationary PCR based on time domain and shuttling PCR based on space domain. In the experimental setting of stationary PCR, the PCR reaction droplets stay on an electrode for in situ PCR reaction, and thermal cycling is achieved by controlling the heating time. The heater can be a large external heater that heats and cools the entire chip, or an on-chip heater with a smaller heating volume. In the real-time process of using PCR methods in microfluidics for qualitative and quantitative analysis, first, the reagents need to be heated to 95°C; second, most PCRs use fluorescence methods and require the cooperation of optical modules. At this temperature, the reagents are easily evaporated and produce bubbles, which affects the reagent morphology and makes it impossible to read the amplification curve.

An existing microfluidic chip includes a conductive cover plate and a chip substrate, wherein a TEFLON hydrophobic layer is disposed on one side of the conductive cover plate and adjacent to the chip substrate, and an expanded PTFE film is disposed on one side of the chip substrate adjacent to the conductive cover plate to reduce or avoid bubbles generated during amplification reactions of the microfluidic chip. However, this method is costly and relatively complex to manufacture, and is not suitable for mass production.

There is also a microfluidic chip in which a hydrophilic layer is coated on one side of the conductive cover plate adjacent to the chip substrate, and a hydrophobic layer is disposed on the other side of the chip substrate adjacent to the conductive cover plate. However, once bubbles are generated in this solution, the sample reagent is easily pushed by the generated bubbles, thereby causing the sample to move and hindering observation.

An existing integrated microfluidic chip includes a lysis chamber, a cleaning chamber, an elution chamber, a liquid path chamber, and an amplification chamber that are connected in sequence. Lysis solution is pre-stored in the lysis chamber, washing solution is pre-stored in the cleaning chamber, and elution solution is pre-stored in the elution chamber. The elution chamber and the liquid path chamber are usually separated by an insulating material such as a paraffin valve, and an electrode array is usually not provided on the substrate directly below the elution chamber. However, the storage method of the eluent of the microfluidic chip is relatively cumbersome, because it takes time to heat and melt the paraffin valve in sequence, resulting in a slow detection efficiency, and the substrate located directly below the elution chamber is usually not provided with an electrode array, and it is impossible to move all the eluted sample droplets to the liquid path chamber, resulting in inaccurate sample detection.

In order to move all the eluted sample droplets into the liquid path cavity, some existing microfluidic chips usually use air pumps or gravity to move the sample droplets into the liquid path cavity. Both operations are cumbersome and complicated, and the latter cannot perform more sophisticated operations, such as liquid separation.

An existing microfluidic chip includes a liquid storage electrode, a liquid separation electrode and a solid-liquid electrode adjacent to each other in sequence. The width of the liquid storage electrode is greater than that of the solid-liquid electrode, and the width of the liquid separation electrode is less than that of the solid-liquid electrode. Before liquid separation, the sample droplet covers the entire liquid storage electrode and part of the liquid separation electrode; when transferring liquid, the liquid separation electrode is first energized, and the sample droplet occupies most of the liquid storage electrode, covers the liquid separation electrode, and occupies most of the solid-liquid electrode; at this time, the liquid separation electrode is turned off, and the liquid storage electrode and the solid-liquid electrode are energized at the same time, and the sample droplet quickly splits, and finally the liquid storage electrode and the solid-liquid electrode are turned off. At this time, the sample droplet separated from the liquid storage electrode The droplets are located on the solid-liquid electrode. However, when this method is used to separate sample droplets, when the liquid separation electrode is powered off, the sample droplets on the liquid separation electrode are too large, and the droplets split slowly during liquid separation, resulting in uneven droplet splitting, which leads to insufficient droplets on the solid-liquid electrode to meet the test requirements; or too many droplets on the solid-liquid electrode, which affects the accuracy of the experiment.

technical problem

The first object of the present invention is to provide a microfluidic chip which is convenient for storing and moving eluent, can improve detection efficiency, and can fully move sample droplets in the elution chamber to the liquid path chamber.

The second object of the present invention is to provide a microfluidic chip that can split sample droplets evenly and accurately during liquid separation.

The third object of the present invention is to provide a microfluidic chip that reduces the influence of bubbles on the detection results during the PCR process.

A fourth object of the present invention is to provide a method for manufacturing a conductive cover plate used for the above-mentioned microfluidic chip.

A fifth object of the present invention is to provide a method for using the above-mentioned microfluidic chip.

A sixth object of the present invention is to provide a microfluidic system comprising the above-mentioned microfluidic chip.

Technical Solutions

In order to achieve the above-mentioned first purpose, the microfluidic chip provided by the present invention includes an extraction component and an amplification component, the extraction component includes a lysis chamber, a first valve chamber, a cleaning chamber and a second valve chamber connected in sequence; the amplification component includes a chip substrate, a barrier layer and a conductive cover plate; the barrier layer is located between the chip substrate and the conductive cover plate, and the barrier layer, the chip substrate and the conductive cover plate surround an elution chamber, a liquid path chamber and an amplification chamber connected in sequence, and the elution chamber and the second valve chamber are connected through a first channel; an electrode array is arranged on the chip substrate; a cavity with a bottom opening is arranged on one side of the conductive cover plate adjacent to the chip substrate, and the elution chamber contains the cavity; the electrode array is located directly below the elution chamber, the liquid path chamber and the amplification chamber; the amplification component also includes a storage chamber for storing a surfactant, and the storage chamber is connected to the elution chamber through a second channel; the liquid path chamber includes a liquid storage cavity, and the liquid storage cavity is adjacent to the elution chamber; along the thickness direction of the microfluidic chip, the thickness of the cavity is 0.6mm to 2mm.

A further solution is that the electrode array includes an elution electrode area and a first liquid storage electrode area adjacent to each other, the elution electrode area includes at least one elution electrode, and the projection of the elution electrode on the chip substrate is located in the elution cavity; the first liquid storage electrode area includes a first transition electrode and a first liquid storage electrode group adjacent to each other, and the projection of the first transition electrode on the chip substrate is that the first transition electrode spans the elution cavity and the liquid storage cavity, and the first transition electrode is located between the elution electrode area and the first liquid storage electrode group, and the first liquid storage electrode group is located in the liquid storage cavity.

A further solution is that the first liquid storage electrode group includes at least two first liquid storage electrodes, and the multiple first liquid storage electrodes are arranged in sequence along the direction from the elution chamber to the liquid path chamber, the area of the next first liquid storage electrode is larger than the area of the previous first liquid storage electrode, and the previous first liquid storage electrode is close to the first transition electrode relative to the next first liquid storage electrode.

A further solution is that each first liquid storage electrode includes a first side edge and a second side edge extending in the direction from the elution chamber to the liquid path chamber, the first side edge and the second side edge are opposite, and the width between the first side edge and the second side edge of the next first liquid storage electrode is greater than the width between the first side edge and the second side edge of the previous first liquid storage electrode.

A further solution is that the first sides of all the first liquid storage electrodes are collinearly arranged, and the second sides of all the first liquid storage electrodes are collinearly arranged.

A further solution is that the first transition electrode and the first liquid storage electrode adjacent to the first transition electrode have mutually interlocking first arc-shaped portions, the opening of the first arc-shaped portion faces the first transition electrode; and the two adjacent first liquid storage electrodes have mutually interlocking second arc-shaped portions, the opening of the second arc-shaped portions faces the first transition electrode.

A further solution is that at least one first arc segment is arranged in the first arc portion, and the opening of the first arc segment faces away from the first transition electrode; at least one second arc segment is arranged in the second arc portion, and the opening of the second arc segment faces away from the first transition electrode.

A further solution is that the conductive cover plate includes a plate body and a cover body; the top of the cavity is open, and the cover body covers the top opening of the cavity.

In order to achieve the above-mentioned second purpose, the microfluidic chip provided by the present scheme includes an amplification component, which includes a chip substrate, a barrier layer and a conductive cover plate; the chip substrate and the conductive cover plate are arranged opposite to each other; the chip substrate includes a substrate plate, an electrode array and an insulating layer, the electrode array is located on the substrate plate, and the insulating layer covers the electrode array and is adjacent to the conductive cover plate; the barrier layer is located between the chip substrate and the conductive cover plate, and an accommodating portion is formed between the barrier layer, the chip substrate and the conductive cover plate, and the electrode array corresponds to the accommodating portion; the electrode array includes a second liquid storage electrode area, a liquid separation electrode area and a solid-liquid electrode area adjacent to each other in sequence; the width of the solid-liquid electrode area and the width of the second liquid storage electrode area are both greater than the width of the liquid separation electrode area; the solid-liquid electrode area includes at least one solid-liquid electrode; the second liquid storage electrode area includes at least one second liquid storage electrode; the liquid separation electrode area includes a liquid separation part, and the liquid separation part includes a first electrode and a second electrode adjacent to each other along the width direction of the liquid separation part; the area of the second electrode is smaller than the area of the solid-liquid electrode.

A further solution is that the liquid-separating electrode area further includes a liquid-transferring portion, the liquid-transferring portion includes at least one liquid-transferring electrode, and the liquid-transferring portion is located between the liquid-separating portion and the second liquid-storage electrode area.

A further solution is that the width direction of the solid-liquid electrode intersects with the width direction of the pipetting part, the width direction of the first end of the liquid separating part is parallel to the width direction of the pipetting part, the first end of the liquid separating part is adjacent to the pipetting part, the width direction of the second end of the liquid separating part is parallel to the width direction of the solid-liquid electrode area, and the second end of the liquid separating part is adjacent to the solid-liquid electrode area.

A further solution is that the width direction of the solid-liquid electrode area and the width direction of the liquid transfer part are perpendicular to each other.

A further solution is that the second liquid storage electrode area includes more than two second liquid storage electrodes adjacent to each other, and the two adjacent second liquid storage electrodes have first arcuate edge portions that are interlocked with each other, and the opening of the first arcuate edge portions faces the liquid separation electrode area; the solid-liquid electrode area includes more than two solid-liquid electrodes adjacent to each other, and the two adjacent solid-liquid electrodes have second arcuate edge portions that are interlocked with each other, and the opening of the second arcuate edge portions faces the liquid separation electrode area.

A further solution is that a third arcuate edge portion is arranged inside the first arcuate edge portion, and an opening of the third arcuate edge portion faces away from the liquid-separating electrode area; a fourth arcuate edge portion is arranged inside the second arcuate edge portion, and an opening of the fourth arcuate edge portion faces away from the liquid-separating electrode area.

A further solution is that the area of the first electrode is larger than the area of the second electrode.

A further solution is that the shape of the second electrode includes an isosceles triangle, the hypotenuse of the second electrode is adjacent to the first electrode, and the liquid transfer portion and the solid-liquid electrode area are adjacent to two right-angled sides of the second electrode respectively.

A further solution is that the second liquid storage electrode area also includes two second transition electrodes, the transfer electrode adjacent to the second liquid storage electrode is located between the two second transition electrodes, and each second transition electrode is adjacent to the second liquid storage electrode and the transfer electrode respectively.

A further solution is that the liquid separating portion includes a first tooth-shaped portion, a second tooth-shaped portion and a third tooth-shaped portion; the first tooth-shaped portion is located at the edge of the liquid separating portion adjacent to the solid-liquid electrode area, and is interlocked with the edge of the solid-liquid electrode area; the second tooth-shaped portion is located at the edge of the liquid separating portion adjacent to the pipetting portion, and is interlocked with the edge of the pipetting portion; the third tooth-shaped portion is located at the edge of the second electrode adjacent to the first electrode, and is interlocked with the first electrode.

In order to achieve the above-mentioned third purpose, the microfluidic chip provided by the present invention includes an amplification component, which includes a chip substrate, a conductive cover, a barrier layer and a first hydrophobic layer; the first hydrophobic layer is located on the side of the insulating layer adjacent to the conductive cover; the chip substrate and the conductive cover are arranged opposite to each other; the chip substrate includes a substrate plate, an electrode array and an insulating layer; the electrode array is located on the substrate plate, and the insulating layer covers the electrode array; the barrier layer is located between the chip substrate and the conductive cover, and a liquid path cavity and an amplification cavity that are interconnected are formed between the barrier layer, the chip substrate and the conductive cover, and the liquid path cavity and the amplification cavity are arranged correspondingly to the electrode array; the conductive cover includes a liquid path area and an amplification area that are interconnected, the liquid path area corresponds to the liquid path cavity, and the amplification area corresponds to the amplification cavity; the amplification component also includes an adjacent second hydrophobic layer and a hydrophilic layer; the hydrophilic layer is located on the side of the amplification area adjacent to the chip substrate; the second hydrophobic layer is located on the side of the liquid path area adjacent to the chip substrate, and the second hydrophobic layer, the hydrophilic layer and the first hydrophobic layer are arranged opposite to each other.

A further solution is that the barrier layer includes a mixture of glue and plastic beads, and the distance between the chip substrate and the conductive cover plate is equal to the diameter of the plastic beads.

A further solution is that the ratio of the density of the glue to the density of the plastic beads is greater than or equal to 95%.

A further solution is that the microfluidic chip includes an extraction component, which is connected to the amplification component; the extraction component includes a lysis chamber, a cleaning chamber and an elution chamber which are connected in sequence; the lysis chamber, the cleaning chamber and the elution chamber are separated by a paraffin valve; the microfluidic chip also includes a heating unit arranged in the chip substrate, the heating unit includes a first heating wire and a second heating wire arranged in the substrate plate, the first heating wire corresponds to the paraffin valve, and the second heating wire corresponds to the amplification chamber.

In order to achieve the above-mentioned fourth purpose, the manufacturing method of the conductive cover provided by the present invention is applied to any of the above-mentioned microfluidic chips, and the method comprises the following steps: coating a first hydrophobic layer on the conductive cover, mounting the conductive cover coated with the first hydrophobic layer on a fixing fixture, and erasing the first hydrophobic layer on the surface of the amplification area using an erasing tool.

A further solution is to perform a hydrophilic treatment on the surface of the amplification area where the first hydrophobic layer has been erased.

A further solution is that the fixture is fixed so that the conductive cover plate is exposed only in the amplification area.

In order to achieve the fifth purpose mentioned above, the present invention provides a method for using the microfluidic chip of the first purpose mentioned above, the method comprising: a magnetic suction device controls the sample droplets to be tested with magnetic beads to pass through the lysis chamber and the cleaning chamber in sequence and then move to the elution chamber, the magnetic suction device controls the magnetic beads so that the magnetic beads move back and forth between the storage chamber and the elution chamber, and the electrode array is energized so that the sample droplets in the elution chamber enter the liquid storage chamber.

In order to achieve the sixth objective, the microfluidic system provided by the present invention includes the microfluidic system of the microfluidic chip. The system also includes a drive circuit and a control terminal: the control terminal is electrically connected to the drive circuit, and the control terminal is used to send a control instruction to the drive circuit; the drive circuit is electrically connected to the electrode array, and the drive circuit is used to control the change of the power-on state of the electrode array.

A further solution is that the microfluidic system also includes a magnetic suction device and a fluorescence detection device, the magnetic suction device is used to control the movement of the sample in the extraction structure extraction component; the fluorescence detection device is used to detect the result of the sample after amplification in the amplification area.

Beneficial Effects

The thickness of the peripheral wall of the cavity of the microfluidic chip of the present invention is 0.6 mm to 2 mm. Since the surface tension of the eluent without adding a surfactant is relatively high, the eluent is blocked by the side wall of the cavity and cannot enter the liquid storage cavity and the storage cavity. There is no need to separate the liquid storage cavity and the elution cavity through barriers such as paraffin valves, which is convenient for operation and production. An electrode array is arranged below the elution cavity, and through the effect of electrowetting, the liquid in the elution cavity can all enter the liquid storage cavity. The operation is convenient and a variety of sophisticated operations can be completed.

The first transition electrode provided in the present invention can make the sample droplets move from the elution chamber to the liquid storage chamber more conveniently and smoothly, preventing the sample droplets from being unable to move or unable to move completely into the liquid storage chamber due to the dual effects of the obstruction of the elution chamber wall and the gap between the electrodes.

The area of the next first liquid storage electrode of the present invention is larger than that of the previous first liquid storage electrode, so that the liquid storage cavity can fully temporarily store the sample droplets to be tested, and can meet the needs of a large number of sample tests.

The width between the first side and the second side of the next first liquid storage electrode of the present invention is greater than that of the previous first liquid storage electrode, which can effectively reduce the volume of the chip and make the structure more compact.

The first side edges of all the first liquid storage electrodes of the present invention are collinearly arranged, and the second side edges of all the first liquid storage electrodes are collinearly arranged, so that the sample droplets move faster.

The present invention enables the sample droplet to move more smoothly between two adjacent electrodes by providing the first arc portion, the first arc segment, the second arc portion and the second arc segment.

The present invention provides a first electrode and a second electrode arranged in parallel along the width direction of the liquid separation portion. When one of the electrodes is powered on, the volume of the sample droplet on the liquid separation electrode area can be effectively reduced to ensure that the electrode droplet will not suddenly separate. When the electrodes in the liquid separation zone are not energized, the sample droplets can split quickly, and the size of the split droplets is more precise, which can meet the experimental requirements.

When the liquid separation part of the present invention is directly adjacent to the second liquid storage electrode and performs liquid separation, the second liquid storage electrode obtains more droplets, thereby affecting the volume of sample droplets obtained on the solid-liquid electrode. The liquid transfer part provided in this solution can lengthen the length of the liquid separation electrode area, making the droplet splitting more uniform and more accurate.

The width direction of the solid-liquid electrode of the present invention is perpendicular to the width direction of the liquid transfer electrode, so that the electrode array is arranged more reasonably and the size of the microfluidic chip is effectively reduced.

The present invention designs the area size of each solid-liquid electrode, calculates the area size of the required sample droplet according to the demand, thereby controlling how many solid-liquid electrodes the sample droplet covers, thereby obtaining a sample droplet of more precise size, and two adjacent solid-liquid electrodes have a second arc-shaped edge portion with an opening toward the liquid-separating electrode area, which can accelerate the speed of the sample droplet located on the solid-liquid electrode moving from the liquid-separating electrode area toward the solid-liquid electrode area. The number of second liquid storage electrodes includes more than two, and two adjacent second liquid storage electrodes have a first arc-shaped edge portion with an opening toward the liquid-separating electrode area that fits with each other, which can accelerate the speed of the sample droplet located in the second liquid storage electrode area moving from the liquid-separating electrode area toward the second liquid storage electrode area. In this way, when liquid is separated, multiple second liquid storage electrodes are energized to accelerate the splitting of sample droplets.

In the present invention, a third arc-shaped edge portion is arranged inside the first arc-shaped edge portion, facing away from the opening of the liquid-separating electrode area, so that the sample droplets located on the second liquid storage electrode area move more smoothly; a fourth arc-shaped edge portion is arranged inside the second arc-shaped edge portion, facing away from the opening of the liquid-separating electrode area, so that the sample droplets located on the solid-liquid electrode area move more smoothly.

The area of the first electrode of the present invention is larger than that of the second electrode, so when the first electrode is powered off and the second electrode remains powered on, there are fewer sample droplets on the second electrode. After the second electrode is powered off, the sample droplets on the second electrode can be quickly split.

The second electrode of the present invention is in the shape of an isosceles triangle, so that the sample droplets are more evenly split.

The present invention arranges transition electrodes on both sides of the transfer electrode adjacent to the second liquid storage electrode to prevent the sample droplet from moving to cover the outside of the transfer electrode when moving from the second liquid storage electrode to the transfer electrode, thereby fully controlling the movement of the sample droplet.

The present invention provides the first tooth-shaped portion, the second tooth-shaped portion and the third tooth-shaped portion, so that the sample droplet moves more smoothly when passing through the liquid transfer electrode, the liquid separation electrode and the solid-liquid electrode in sequence.

Since the aqueous reagent and the sample to be tested have strong wettability on the hydrophilic surface, the reagent has a strong adsorption effect on the hydrophilic surface. The conductive cover plate provided with a hydrophilic layer in the present invention has a good air-repelling effect, and the aqueous reagent and the sample to be tested diffuse more fully in the amplification area. The chip substrate is coated with a first hydrophobic coating, so that the generation of bubbles can be reduced or even avoided during the amplification reaction. After the chip substrate is heated, the bubbles generated by the aqueous reagent and the sample to be tested can be quickly discharged to avoid continuous evaporation of the reagent, thereby affecting the observation. The second hydrophobic layer provided in the liquid path area surrounds the hydrophilic layer, so that the reagent can stably perform the amplification reaction in the amplification area, preventing the reagent from being pushed away by the generated bubbles, thereby affecting the observation.

The present invention mixes glue with plastic beads of specified diameter so that the glue can achieve sealing and bonding effects while accurately limiting the height between two planes. Compared with the method of using gaskets and glue to limit the height in traditional processes, this solution reduces the difficulty of processing and shortens the processing time.

The density of the plastic beads of the present invention is close to that of the glue, so that the plastic beads can be evenly dispersed in the glue, thereby avoiding the situation of uneven particle sedimentation.

The present invention can effectively simplify the operation process by combining the extraction component and the amplification component. The paraffin valve can effectively separate the reagents pre-stored between different chambers in the extraction component to prevent contamination between different reagents. The heating wire is arranged in the substrate plate to effectively reduce the volume of the microfluidic chip.

The present invention performs hydrophilic treatment on the surface of the amplification area where the hydrophobic coating has been removed, which can effectively improve the hydrophilicity of the amplification area.

The present invention fully mixes the surfactant and sample droplets in the storage cavity through the reciprocating motion of the magnetic beads, reduces the surface tension of the sample droplets, and facilitates the movement of the sample droplets.

In summary, the microfluidic chip of the present invention can reduce the risk of bubbles generated during the PCR process, while allowing the sample reagents in the amplification zone to be stably present for easy observation. The chip has a simple and compact structure, is convenient for storing eluent, has a larger capacity, can accelerate the detection efficiency, and allows the sample droplets in the elution chamber to be fully moved to the liquid path chamber. At the same time, during the liquid separation process, the sample droplets can be controlled to split evenly, and the size of the sample droplet split can be controlled more accurately.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a structural diagram of a microfluidic chip embodiment of the present invention from a first viewing angle.

FIG. 2 is a structural diagram showing a microfluidic chip embodiment of the present invention, in which a conductive cover is divided into a liquid path area and an amplification area from a second viewing angle.

FIG. 3 is a structural diagram of the division of the various cavity regions from a second viewing angle of an embodiment of the microfluidic chip of the present invention.

FIG. 4 is a cross-sectional view of an amplification component of a microfluidic chip embodiment of the present invention.

FIG5 is a cross-sectional view of an extraction component of a microfluidic chip embodiment of the present invention.

FIG. 6 is a diagram showing a state in which a sample to be tested is located between two hydrophobic layers in an amplification region of an existing microfluidic chip.

FIG. 7 is a state diagram of a sample to be tested being located in the amplification zone of an embodiment of the microfluidic chip of the present invention.

FIG8 is a partial cross-sectional view of an embodiment of the microfluidic chip of the present invention including an elution chamber, a first channel and a liquid path chamber.

FIG. 9 is a partial cross-sectional view of an embodiment of the microfluidic chip of the present invention including an elution chamber and a storage chamber.

FIG. 10 is a schematic plan view of the elution electrode region and the first liquid storage electrode region of the microfluidic chip embodiment of the present invention.

FIG. 11 is a plan view schematically showing an electrode array according to an embodiment of the present invention.

FIG. 12 is an enlarged view of point A in FIG. 11 .

FIG. 13 is a diagram showing a first state of a sample droplet on an electrode array according to an embodiment of the present invention.

FIG. 14 is a diagram showing a second state of a sample droplet on an electrode array according to an embodiment of the present invention.

FIG. 15 is a diagram showing a third state of a sample droplet on an electrode array according to an embodiment of the present invention.

FIG. 16 is a diagram showing a fourth state of a sample droplet on an electrode array according to an embodiment of the present invention.

FIG. 17 is a structural block diagram of an embodiment of a microfluidic system of the present invention.

Embodiments of the present invention

Referring to Fig. 1 to Fig. 7, the microfluidic chip 304 of the present embodiment comprises an extraction cover plate 3, a conductive cover plate 4, a barrier layer 5 and a chip substrate 6, wherein the extraction cover plate 3 is adjacent to the conductive cover plate 4, and the conductive cover plate 4 and the extraction cover plate 3 are arranged opposite to the chip substrate 6, and the extraction cover plate 3 and the chip substrate 6 are combined to form an extraction component 1, and the extraction component 1 comprises a lysis chamber 100, a first valve chamber 101, a first cleaning chamber 102, a second cleaning chamber 103 and a second valve chamber 104 which are connected in sequence, and the first valve chamber 101 and the second valve chamber 104 are filled with paraffin. The barrier layer 5, the chip substrate 6 and the conductive cover plate 4 are combined to form an amplification component 2, wherein the barrier layer 5 is located between the conductive cover plate 4 and the chip substrate 6, and the barrier layer 5, the chip substrate 6 and the conductive cover plate 4 are surrounded by a receiving portion 10, and the receiving portion 10 comprises a storage chamber 20, an elution chamber 21, a liquid path chamber 22 and an amplification chamber 23 which are connected in sequence, and the elution chamber 21 and the second valve chamber 104 are connected through a first channel 24. Optionally, the number of cleaning chambers is at least one. The chip substrate 6 includes a substrate plate 60, an electrode array 7 and an insulating layer 61, wherein the electrode array 7 is located on the substrate plate 60, the insulating layer 61 covers the electrode array 7 and is adjacent to the conductive cover plate 4, and the electrode array 7 is disposed corresponding to the receiving portion 10.

The amplification component 2 further includes a first hydrophobic layer 26, a hydrophilic layer 28, and a second hydrophobic layer 27. The first hydrophobic layer 26 is located on a side of the insulating layer 61 adjacent to the conductive cover 4. The conductive cover 4 includes a liquid path area 42 and an amplification area 43 connected to each other. The liquid path area 42 corresponds to the liquid path cavity 22, and the amplification area 43 corresponds to the amplification cavity 23. The hydrophilic layer 28 is located in the amplification area The side of the liquid path region 43 adjacent to the chip substrate 6 , the hydrophilic layer 28 is arranged opposite to the first hydrophobic layer 26 . The side of the liquid path region 42 adjacent to the chip substrate 6 is coated with the second hydrophobic layer 27 , and the hydrophilic layer 28 is adjacent to the second hydrophobic layer 27 .

Since the amplification area 43 is surrounded by a hydrophobic layer, the sample reagent can stably contact the hydrophilic layer 28 and will not be pushed away by the generated bubbles. Moreover, since the side of the chip substrate 6 opposite to the amplification area 43 is a hydrophobic layer, the contact area between the sample reagent and the hydrophobic layer is smaller than that of the hydrophilic layer 28, which can reduce or even avoid the generation of bubbles, and the generated bubbles can be quickly discharged.

The present embodiment also provides a method for manufacturing a conductive cover plate 4, which is used to manufacture the above-mentioned microfluidic chip 304. First, a first hydrophobic layer 26 is coated on the conductive cover plate 4, and the conductive cover plate 4 coated with the first hydrophobic layer 26 is set on a fixed fixture (not shown in the figure), and the fixed fixture only exposes the conductive cover plate 4 to the amplification area 43, and the first hydrophobic layer 26 on the surface of the amplification area 43 is erased using an erasing tool such as a cotton swab. Optionally, in order to further improve the hydrophilicity of the ITO glass, a hydrophilic coating is coated on the surface of the amplification area 43 from which the hydrophobic coating has been erased, or the surface of the amplification area 43 is hydrophilically treated using laser, etching, or plasma methods.

A heating unit 62 is disposed in the substrate plate 60, and the heating unit 62 includes a first heating wire (not shown in the figure) and a second heating wire (not shown in the figure), and the first heating wire is correspondingly disposed directly below the first valve chamber 101 and the second valve chamber 104, and the second heating wire is located directly below the amplification chamber 23. The insulating layer 61 may be a dielectric layer.

The barrier layer 5 includes a mixture of glue and plastic beads, wherein the density of the glue is similar to that of the plastic beads, for example, the ratio of the density of the glue to the density of the plastic beads is greater than or equal to 95%. Optionally, the barrier layer 5 includes a gasket (not shown in the figure) and glue (not shown in the figure). The spacing between the conductive cover plate 4 and the chip substrate 6 is equal to the diameter of the plastic beads.

In conjunction with Figures 8 and 9, the conductive cover plate 4 can be ITO glass. The conductive cover plate 4 includes a plate body 40 and a cover body 41. The plate body 40 is provided with a cavity 400 with both bottom and top openings. The bottom opening of the cavity 400 is located on the side of the plate body 40 adjacent to the chip substrate 6, and the top opening of the cavity 400 is located on the side of the plate body 40 away from the chip substrate 6. The cover body 41 covers the top opening of the cavity 400, and the elution chamber 21 includes the cavity 400. Optionally, the cover body 41 is integrally formed with the plate body 40.

The extraction cover plate 3 is provided with a first loading hole 30, a second loading hole 31 and a third loading hole 32. The first loading hole 30 is connected to the lysis chamber 100, the second loading hole 31 is connected to the first cleaning chamber 102, and the third loading hole 32 is connected to the second cleaning chamber 103. The cover body 41 is provided with a fourth loading hole 410, which is connected to the elution chamber 21. The lysis chamber 100 is pre-stored with a lysate, the first cleaning chamber 102 and the second cleaning chamber 103 are pre-stored with a washing solution, and the elution chamber 21 is pre-stored with an elution solution. The positions corresponding to the first valve chamber 101 and the second valve chamber 104 on the chip substrate 6 are all provided with heating wires (not shown in the figure) for melting the paraffin in the first valve chamber 101 and the second valve chamber 104. The electrode array 7 is located directly below the elution chamber 21, the liquid path chamber 22 and the amplification chamber 23.

A surfactant (not shown in the figure) is pre-stored in the storage chamber 20, and the solidified surfactant can be pre-stored in the storage chamber 20 by freeze-drying or drying. The storage chamber 20 is connected to the elution chamber 21 through the second channel 25. The liquid path chamber 22 includes a liquid storage chamber 220 and a liquid separation chamber 221 arranged in sequence along the direction from the liquid path chamber 22 to the amplification chamber 23. The liquid storage chamber 220 is adjacent to the elution chamber 21, and the liquid separation chamber 221 is adjacent to the amplification chamber 23. Along the thickness direction of the microfluidic chip 304, the thickness c of the cavity 400 is 0.6mm to 2mm, the distance b between the top wall of the first channel 24 and the upper surface of the chip substrate 6 is less than 7mm and greater than or equal to 4mm, the distance d between the top wall of the second channel 25 and the upper surface of the chip substrate 6 is less than 7mm and greater than or equal to 4mm, and the distance a between the top wall of the liquid storage chamber 220 and the upper surface of the chip substrate 6 is less than 7mm and greater than or equal to 4mm.

Referring to Fig. 2, Fig. 3, and in combination with Fig. 10, the electrode array 7 includes an elution electrode area 70, a first liquid storage electrode area 71, a second liquid storage electrode area 72, a liquid separation electrode area 73, a solid-liquid electrode area 74, and an amplification electrode area 75, which are adjacent to each other in sequence. In the projection on the chip substrate 6, the elution electrode area 70 is located in the elution cavity 21, and the first liquid storage electrode area 71, the second liquid storage electrode area 72, the liquid separation electrode area 73, and the solid-liquid electrode area 74 are located in the liquid path cavity 22. The amplification electrode area 75 is located in the liquid path cavity 22. in the amplification chamber 23. The elution electrode area 70 includes an elution electrode 700. The first liquid storage electrode area 71 includes a first transition electrode 710 and a first liquid storage electrode group 8 adjacent to each other, and the projection on the chip substrate 6, the first transition electrode 710 spans the elution chamber 21 and the liquid storage chamber 220, the first transition electrode 710 is located between the elution electrode area 70 and the first liquid storage electrode group 8, and the first liquid storage electrode group 8 is located in the liquid storage chamber 220. Optionally, the elution electrode area 70 includes more than one elution electrode 700, and the multiple elution electrodes 700 are arranged in sequence along the direction from the elution chamber 21 to the liquid path chamber 22.

The first liquid storage electrode group 8 includes three first liquid storage electrodes 80, and the three first liquid storage electrodes 80 are arranged in sequence along the direction from the elution chamber 21 to the liquid path chamber 22. The area of the next first liquid storage electrode 80 is larger than the area of the previous first liquid storage electrode 80, and the previous first liquid storage electrode 80 is closer to the first transition electrode 710 relative to the next first liquid storage electrode 80. Each first liquid storage electrode 80 includes a first side and a second side extending along the direction from the elution chamber 21 to the liquid path chamber 22, the first side and the second side are opposite, and the width between the first side and the second side of the next first liquid storage electrode is larger than the width between the first side and the second side of the previous first liquid storage electrode. The first sides of all the first liquid storage electrodes are collinearly arranged, and the second sides of all the first liquid storage electrodes are collinearly arranged. Optionally, the number of the first liquid storage electrodes 80 includes more than two.

The first transition electrode 710 and the first liquid storage electrode 80 adjacent to the first transition electrode 710 have mutually interlocking first arc-shaped portions 802, the opening of the first arc-shaped portion 802 faces the first transition electrode 710; two adjacent first liquid storage electrodes 80 have mutually interlocking second arc-shaped portions 804, the opening of the second arc-shaped portion 804 faces the first transition electrode 710. Three first arc-shaped segments 803 are arranged at intervals in the first arc-shaped portion 802, the opening of the first arc-shaped segment 803 faces away from the first transition electrode 710; three second arc-shaped segments 805 are arranged in the second arc-shaped portion 804, the opening of the second arc-shaped segment 805 faces away from the first transition electrode 710. Optionally, the number of the first arc-shaped segments 803 is at least one, and the number of the second arc-shaped segments 805 is at least one.

In conjunction with Figures 11 and 12, the solid-liquid electrode area 74 includes solid-liquid electrodes 740 and solid-liquid electrodes 741 that are adjacent in sequence, and the second liquid storage electrode area 72 includes second liquid storage electrodes 90, second liquid storage electrodes 91, and second liquid storage electrodes 92 that are adjacent in sequence. Optionally, the number of solid-liquid electrodes and second liquid storage electrodes is determined according to design requirements. The liquid separation electrode area 73 includes a liquid separation portion 730 and a liquid transfer portion 736, and the liquid transfer portion 736 is located between the liquid separation portion 730 and the second liquid storage electrode 92. The liquid separation portion 730 includes a first electrode 731 and a second electrode 732 that are arranged in parallel along the width direction of the liquid separation portion 730, and the area of the second electrode 732 is smaller than the area of the first electrode 731. The widths a and b of the liquid separation electrode area 73 are both smaller than the width c of the solid-liquid electrode area 74, and the width e of the second liquid storage electrode area 72 is larger than the width c of the solid-liquid electrode area 74.

The width direction c of the solid-liquid electrode area 74 is perpendicular to the width direction d of the liquid transfer part 736, the width direction b of the first end of the liquid separation part 730 is parallel to the width direction d of the liquid transfer part 736, the first end of the liquid separation part 730 is adjacent to the liquid transfer part 736, the width direction a of the second end of the liquid separation part 730 is parallel to the width direction c of the solid-liquid electrode area 74, and the second end of the liquid separation part 730 is adjacent to the solid-liquid electrode area 74. The shape of the second electrode 732 includes an isosceles triangle, the hypotenuse of the second electrode 732 is adjacent to the first electrode 731, and the liquid transfer part 736 and the solid-liquid electrode area 74 are respectively adjacent to the two right-angled sides of the second electrode 732. Optionally, the shape of the second electrode 732 can be a triangle or a square.

In this embodiment, there is a first arcuate edge portion 900 interlocked with each other between the adjacent second liquid storage electrode 91 and the second liquid storage electrode 92, and the opening of the first arcuate edge portion 900 faces the liquid separation electrode area 73. There is a second arcuate edge portion 743 interlocked with each other between the adjacent solid-liquid electrode 740 and the solid-liquid electrode 741, and the opening of the second arcuate edge portion 743 faces the liquid separation electrode area 73. A third arcuate edge portion 901 is arranged in the first arcuate edge portion 900, and the opening of the third arcuate edge portion 901 faces away from the liquid separation electrode area 73, and a fourth arcuate edge portion 744 is arranged in the second arcuate edge portion 743, and the opening of the fourth arcuate edge portion 744 faces away from the liquid separation electrode area 73. Optionally, the number of the third arcuate edge portions 901 can be more than one, and the number of the fourth arcuate edge portions 744 can be more than one.

The second liquid storage electrode area 72 further includes two second transition electrodes 720. The liquid transfer section 736 includes a liquid transfer electrode 737 and a liquid transfer electrode 738 which are adjacent to each other in the length direction of the liquid transfer section 736. The liquid transfer electrode 738 which is adjacent to the second liquid storage electrode Located between two second transition electrodes 720 , each second transition electrode 720 is adjacent to the second liquid storage electrode 92 and the liquid transfer electrode 738 .

The liquid separating portion 730 includes a first tooth-shaped portion 733, a second tooth-shaped portion 734 and a third tooth-shaped portion 735. The first tooth-shaped portion 733 is located at the edge of the liquid separating portion 730 adjacent to the solid-liquid electrode area 74 and is interlocked with the edge of the solid-liquid electrode area 74. The second tooth-shaped portion 734 is located at the edge of the liquid separating portion 730 adjacent to the pipetting portion 736 and is interlocked with the edge of the pipetting portion 736. The third tooth-shaped portion 735 is located at the edge of the second electrode 732 adjacent to the first electrode 731 and is interlocked with the first electrode 731.

In conjunction with FIG. 13 to FIG. 16 , this embodiment further provides a method for controlling the electrode array 7 when the sample droplets are separated:

The sample mother liquid droplet covers the second liquid storage electrode 92 . At this time, the liquid transfer part 736 , the liquid separation part 730 and the solid-liquid electrode 740 are energized, and the sample mother liquid droplet moves to the solid-liquid electrode 740 .

Then the solid-liquid electrode 740, the solid-liquid electrode 741, the second electrode 732 and the transfer electrode are energized, and the sample mother liquid droplets gradually move to the solid-liquid electrode 741. Since the first electrode 731 is not energized and the second electrode 732 is energized, the sample mother liquid droplets on the liquid separation part 730 are reduced but will not break.

Subsequently, the solid-liquid electrode 740, the solid-liquid electrode 741, the pipetting electrode 737, the pipetting electrode 738, the second liquid storage electrode 92, the second liquid storage electrode 91 and the liquid storage electrode 90 are energized, and the liquid separation part 730 is de-energized. The solid-liquid electrode 741 and the solid-liquid electrode 740 fix the size of the split sample sub-droplets, and the sample mother liquid droplets will move toward the larger electrode direction when the pipetting electrode 737, the pipetting electrode 738, the second liquid storage electrode 92, the second liquid storage electrode 91 and the second liquid storage electrode 90 are energized. The droplets in the liquid separation part 730 gradually decrease, and the sample sub-droplets are separated from the sample mother droplets.

In conjunction with FIG. 17 , the present embodiment further provides a microfluidic system including the above-mentioned microfluidic chip 304, the system including a control terminal 300, a magnetic suction device 301, a fluorescence detection device 302 and a driving circuit 303, the control terminal 300 is electrically connected to the electrode array 7 via the driving circuit 303, the control terminal 300 sends a control instruction to the driving circuit 303, the driving circuit 303 is electrically connected to the electrode array 7, and the driving circuit 303 is used to control the power-on state of the electrode array 7. The control terminal 300 controls the movement of the magnetic suction device 301, thereby controlling the movement of the sample to be tested and the reagent with magnetic beads in the extraction component 1, and the fluorescence detection device 302 is used to detect the result of the sample to be tested after amplification in the amplification area 43.

In combination with Figures 4 and 5, this embodiment also provides a method for using the above-mentioned microfluidic chip 304. The magnetic suction device 301 (not shown in the figure) controls the sample to be tested (not shown in the figure) with magnetic beads to pass through the lysis chamber 100 and the cleaning chamber in sequence and then move to the elution chamber 21. Then the magnetic suction device 301 controls the magnetic beads to make the magnetic beads reciprocate between the storage chamber 20 and the elution chamber 21, so that the surfactant and the sample droplets to be tested are fully mixed, and then the electrode array 7 is energized to allow the sample droplets to enter the liquid storage chamber 220 from the elution chamber 21.

It should be noted that the above are only preferred embodiments of the present invention, but the design concept of the invention is not limited thereto, and any non-substantial modifications made to the present invention using this concept also fall within the protection scope of the present invention.

Industrial Applicability

The microfluidic chip and use method, microfluidic system and conductive cover manufacturing method of the present invention can reduce the risk of bubbles generated in the PCR process by modifying the surface coating of the conductive cover, and at the same time, the sample reagents in the amplification zone can be stably present for easy observation. The chip has a simple and compact structure, and can simplify the process and reduce costs by optimizing the specific cavity size. By optimizing the structure and arrangement of the electrode array, it is convenient to store the eluent, the capacity is larger, the detection efficiency can be accelerated, and the sample droplets in the elution cavity can be fully moved to the liquid path cavity. At the same time, during the liquid separation process, the sample droplets can be controlled to split evenly, and the size of the sample droplet split can be controlled more accurately.

Claims

A microfluidic chip comprises an extraction component and an amplification component, wherein the extraction component comprises a lysis chamber, a first valve chamber, a cleaning chamber and a second valve chamber which are connected in sequence;

The amplification component includes a chip substrate, a barrier layer and a conductive cover plate;

The barrier layer is located between the chip substrate and the conductive cover plate, the barrier layer, the chip substrate and the conductive cover plate enclose an elution chamber, a liquid path chamber and an amplification chamber that are connected in sequence, and the elution chamber and the second valve chamber are connected through a first channel;

An electrode array is arranged on the chip substrate;

Features:

A cavity with a bottom opening is provided on one side of the conductive cover plate adjacent to the chip substrate, and the elution cavity includes the cavity;

The electrode array is located directly below the elution chamber, the liquid path chamber, and the amplification chamber;

The amplification component further comprises a storage chamber for storing a surfactant, and the storage chamber is connected to the elution chamber via a second channel;

The liquid path cavity comprises a liquid storage cavity, and the liquid storage cavity is adjacent to the elution cavity;

Along the thickness direction of the microfluidic chip, the thickness of the cavity is 0.6 mm to 2 mm.
The microfluidic chip according to claim 1, characterized in that:

The electrode array comprises an elution electrode area and a first liquid storage electrode area adjacent to each other, the elution electrode area comprises at least one elution electrode, a projection on the chip substrate, the elution electrode being located in the elution chamber;

The first liquid storage electrode area includes a first transition electrode and a first liquid storage electrode group adjacent to each other. In the projection on the chip substrate, the first transition electrode spans the elution chamber and the liquid storage chamber, and the first transition electrode is located between the elution electrode area and the first liquid storage electrode group. The first liquid storage electrode group is located in the liquid storage chamber.
The microfluidic chip according to claim 2, characterized in that:

The first liquid storage electrode group includes at least two first liquid storage electrodes, and the plurality of first liquid storage electrodes are arranged in sequence along the direction from the elution chamber to the liquid path chamber, the area of the next first liquid storage electrode is larger than the area of the previous first liquid storage electrode, and the previous first liquid storage electrode is closer to the first transition electrode relative to the next first liquid storage electrode.
The microfluidic chip according to claim 3, characterized in that:

Each of the first liquid storage electrodes includes a first side and a second side extending in the direction from the elution chamber to the liquid path chamber, the first side and the second side are opposite, and the width between the first side and the second side of the next first liquid storage electrode is greater than the width between the first side and the second side of the previous first liquid storage electrode.
The microfluidic chip according to claim 4, characterized in that:

The first side edges of all the first liquid storage electrodes are collinearly arranged, and the second side edges of all the first liquid storage electrodes are collinearly arranged.
The microfluidic chip according to any one of claims 3 to 5, characterized in that:

The first transition electrode and the first liquid storage electrode adjacent to the first transition electrode have first arc-shaped portions that fit into each other, and the opening of the first arc-shaped portion faces the first transition electrode;

Two adjacent first liquid storage electrodes have second arc-shaped portions that fit together, and the openings of the second arc-shaped portions face the first transition electrode.
The microfluidic chip according to claim 6, characterized in that:

At least one first arc segment is disposed in the first arc portion, and an opening of the first arc segment faces away from the first transition electrode;

At least one second arc segment is disposed in the second arc portion, and an opening of the second arc segment faces away from the first transition electrode.
The microfluidic chip according to any one of claims 1 to 5, characterized in that:

The conductive cover plate comprises a plate body and a cover body;

The top of the cavity is open, and the cover body covers the top opening of the cavity.
A microfluidic chip, comprising an amplification component, wherein the amplification component comprises a chip substrate, a barrier layer and a conductive cover plate;

The chip substrate is arranged opposite to the conductive cover plate;

The chip substrate comprises a substrate plate, an electrode array and an insulating layer, wherein the electrode array is located on the substrate plate, and the insulating layer covers the electrode array and is adjacent to the conductive cover plate;

The barrier layer is located between the chip substrate and the conductive cover plate, a receiving portion is formed between the barrier layer, the chip substrate and the conductive cover plate, and the electrode array corresponds to the receiving portion;

The electrode array comprises a second liquid storage electrode area, a liquid separation electrode area and a solid-liquid electrode area adjacent to each other in sequence;

The width of the solid-liquid electrode region and the width of the second liquid storage electrode region are both greater than the width of the liquid separation electrode region;

Features:

The solid-liquid electrode area includes at least one solid-liquid electrode;

The second liquid storage electrode area includes at least one second liquid storage electrode;

The liquid separation electrode area includes a liquid separation portion, and the liquid separation portion includes a first electrode and a second electrode adjacently arranged along a width direction of the liquid separation portion;

The area of the second electrode is smaller than the area of the solid-liquid electrode.
The microfluidic chip according to claim 9, characterized in that:

The liquid dispensing electrode area further includes a liquid transfer portion, the liquid transfer portion includes at least one liquid transfer electrode, and the liquid transfer portion is located between the liquid dispensing portion and the second liquid storage electrode area.
The microfluidic chip according to claim 10, characterized in that:

The width direction of the solid-liquid electrode intersects with the width direction of the pipetting part, the width direction of the first end of the liquid separating part is parallel to the width direction of the pipetting part, the first end of the liquid separating part is adjacent to the pipetting part, the width direction of the second end of the liquid separating part is parallel to the width direction of the solid-liquid electrode area, and the second end of the liquid separating part is adjacent to the solid-liquid electrode area.
The microfluidic chip according to claim 11, characterized in that:

The width direction of the solid-liquid electrode area and the width direction of the liquid transfer part are perpendicular to each other.
The microfluidic chip according to any one of claims 9 to 12, characterized in that:

The second liquid storage electrode area includes two or more second liquid storage electrodes that are adjacent to each other in sequence, and the two adjacent second liquid storage electrodes have first arc-shaped edge portions that fit into each other, and the openings of the first arc-shaped edge portions face the liquid-separating electrode area;

The solid-liquid electrode area includes two or more solid-liquid electrodes adjacent to each other in sequence, and two adjacent solid-liquid electrodes have second arc-shaped edge portions that fit together, and the opening of the second arc-shaped edge portions faces the liquid-separating electrode area.
The microfluidic chip according to claim 13, characterized in that:

A third arc-shaped edge portion is disposed inside the first arc-shaped edge portion, and an opening of the third arc-shaped edge portion faces away from the liquid-separating electrode area;

A fourth arc-shaped edge portion is disposed inside the second arc-shaped edge portion, and an opening of the fourth arc-shaped edge portion faces away from the liquid-separating electrode region.
The microfluidic chip according to any one of claims 10 to 12, characterized in that:

An area of the first electrode is greater than an area of the second electrode.
The microfluidic chip according to claim 15, characterized in that:

The second electrode has an isosceles triangle shape, the hypotenuse of the second electrode is adjacent to the first electrode, and the liquid transfer portion and the solid-liquid electrode region are adjacent to two right-angled sides of the second electrode, respectively.
The microfluidic chip according to any one of claims 10 to 12, characterized in that:

The second liquid storage electrode area also includes two second transition electrodes. The transfer electrode adjacent to the second liquid storage electrode is located between the two second transition electrodes. Each of the second transition electrodes is adjacent to the second liquid storage electrode and the transfer electrode respectively.
The microfluidic chip according to any one of claims 10 to 12, characterized in that:

The liquid separation part includes a first tooth-shaped part, a second tooth-shaped part and a third tooth-shaped part;

The first tooth-shaped portion is located at an edge of the liquid separation portion adjacent to the solid-liquid electrode area and is embedded with the edge of the solid-liquid electrode area;

The second tooth-shaped portion is located at an edge of the liquid dispensing portion adjacent to the liquid transfer portion and is engaged with the edge of the liquid transfer portion;

The third tooth-shaped portion is located at an edge of the second electrode adjacent to the first electrode and is embedded with the first electrode.
A microfluidic chip, comprising an amplification component, wherein the amplification component comprises a chip substrate, a conductive cover plate, a barrier layer and a first hydrophobic layer;

The first hydrophobic layer is located on a side of the insulating layer adjacent to the conductive cover plate;

The chip substrate is arranged opposite to the conductive cover plate;

The chip substrate comprises a substrate plate, an electrode array and an insulating layer;

The electrode array is located on the substrate plate, and the insulating layer covers the electrode array;

The barrier layer is located between the chip substrate and the conductive cover plate, and a liquid path cavity and an amplification cavity that are interconnected are formed between the barrier layer, the chip substrate and the conductive cover plate, and the liquid path cavity and the amplification cavity are arranged correspondingly to the electrode array;

Features:

The conductive cover plate comprises a liquid path area and an amplification area connected to each other, the liquid path area corresponds to the liquid path cavity, and the amplification area corresponds to the amplification cavity;

The amplification assembly further includes an adjacent second hydrophobic layer and a hydrophilic layer;

The hydrophilic layer is located on a side of the amplification region adjacent to the chip substrate;

The second hydrophobic layer is located on a side of the liquid path region adjacent to the chip substrate, and the second hydrophobic layer, the hydrophilic layer and the first hydrophobic layer are arranged opposite to each other.
The microfluidic chip according to claim 19, characterized in that:

The barrier layer includes a mixture of glue and plastic beads, and the distance between the chip substrate and the conductive cover plate is equal to the diameter of the plastic beads.
The microfluidic chip according to claim 20, characterized in that:

The ratio of the density of the glue to the density of the plastic beads is greater than or equal to 95%.
The microfluidic chip according to any one of claims 19 to 21, characterized in that:

The microfluidic chip includes an extraction component, and the extraction component is connected to the amplification component;

The extraction component comprises a lysis chamber, a cleaning chamber and an elution chamber which are connected in sequence;

The lysis chamber, the cleaning chamber and the elution chamber are separated by a paraffin valve;

The microfluidic chip also includes a heating unit arranged in the chip substrate, and the heating unit includes a first heating wire and a second heating wire arranged in the substrate plate, the first heating wire corresponds to the paraffin valve, and the second heating wire corresponds to the amplification chamber.
A method for manufacturing a conductive cover plate, applied to a microfluidic chip as claimed in any one of claims 19 to 22, characterized in that it comprises the following steps:

A first hydrophobic layer is coated on a conductive cover plate, the conductive cover plate coated with the first hydrophobic layer is mounted on a fixing fixture, and an erasing tool is used to erase the first hydrophobic layer on the surface of the amplification region.
The method for manufacturing a conductive cover plate according to claim 23, characterized in that:

A hydrophilic treatment is performed on the surface of the amplification region from which the first hydrophobic layer is erased.
The method for manufacturing a conductive cover plate according to claim 23 is characterized in that:

The fixing fixture only exposes the conductive cover plate from the amplification area
A method for using a microfluidic chip, characterized in that the method is applied to the microfluidic chip described in any one of 1 to 8 above, and the method comprises:

The magnetic suction device controls the sample droplets to be tested with magnetic beads to pass through the lysis chamber and the cleaning chamber in sequence and then move to the elution chamber. The magnetic suction device controls the magnetic beads to make the magnetic beads reciprocate between the storage chamber and the elution chamber, and energizes the electrode array so that the sample droplets in the elution chamber enter the liquid storage chamber.
A microfluidic system, characterized in that:

The microfluidic chip according to any one of claims 1 to 22 further comprises a drive circuit and a control terminal:

The control terminal is electrically connected to the drive circuit, and the control terminal is used to send a control instruction to the drive circuit;

The driving circuit is electrically connected to the electrode array, and is used to control the change of the power-on state of the electrode array.
The microfluidic system according to claim 27, characterized in that:

The microfluidic system also includes a magnetic suction device and a fluorescence detection device. The magnetic suction device is used to control the movement of the sample in the extraction component; the fluorescence detection device is used to detect the result of the sample after amplification in the amplification area.