CN219168457U - Flow channel structure of micro-fluidic chip and micro-fluidic chip - Google Patents

Abstract

The application discloses a flow channel structure of a microfluidic chip and the microfluidic chip, and belongs to the technical field of microfluidic chips. The flow channel structure comprises: the back of the flow channel layer is provided with a flow channel; the liquid storage tank is positioned on the front face of the runner layer and integrally formed with the runner layer, and is provided with a liquid storage cavity which is communicated with an inlet of the runner. Through the arrangement of the flow channel layer and the liquid storage tank, the integrated structure scheme of the liquid storage tank and the flow channel layer is matched, so that the detection efficiency of the microfluidic chip is greatly improved, and the sample cost of the microfluidic chip is reduced.

Description

Flow channel structure of micro-fluidic chip and micro-fluidic chip

Technical Field

The application belongs to the technical field of microfluidic chips, and particularly relates to a flow channel structure of a microfluidic chip and the microfluidic chip.

Background

The liquid drop micro-fluidic technology is a technology for forming monodisperse liquid drops in a micro-channel through multiphase fluid shearing and precisely controlling the liquid drops, can realize precise control of reaction parameters in the particle nucleation and growth process, and is used for forming micro-fluidic chips from silicon, glass, quartz, plastics and the like.

In the related art, a plastic microfluidic chip consists of a substrate and a cover plate, a microchannel is formed on the substrate, a sample injection liquid storage tank is processed on the cover plate, and the substrate and the cover plate are integrated into a whole by later bonding to form the complete microfluidic chip. However, the inventor researches find that firstly, the liquid storage tank on the traditional cover plate needs to be processed by a mechanical or laser method after being molded, and the problems of liquid leakage and the like can be caused in use; secondly, the detection sample amount is small, the liquid level of the detection sample is low after the detection sample drops into the liquid storage tank, and for the on-chip liquid storage tank, when the liquid level of the detection sample is too low, bubbles are easily introduced into the flow channel, so that the subsequent formation of liquid drops is influenced.

Disclosure of Invention

The present application aims to solve at least one of the technical problems existing in the prior art. Therefore, the flow channel structure of the microfluidic chip and the microfluidic chip are provided, so that the detection efficiency of the microfluidic chip is greatly improved, and the sample cost of the microfluidic chip is reduced.

In a first aspect, the present application provides a flow channel structure of a microfluidic chip, the flow channel structure comprising:

the back of the flow channel layer is provided with a flow channel;

the liquid storage tank is positioned on the front face of the runner layer and integrally formed with the runner layer, and is provided with a liquid storage cavity which is communicated with an inlet of the runner.

According to the runner structure of the microfluidic chip, through the arrangement of the runner layer and the liquid storage tank, the structure scheme of integrating the liquid storage tank and the runner layer is matched, so that the detection efficiency of the microfluidic chip is greatly improved, and meanwhile, the sample cost of the microfluidic chip is reduced.

According to one embodiment of the application, the liquid storage cavity is in a truncated cone shape, and the upper bottom of the liquid storage cavity is communicated with the inlet of the flow channel.

According to one embodiment of the present application, the diameter of the upper bottom of the liquid storage cavity is smaller than the diameter of the inlet of the flow channel, and a part of the end surface of the liquid storage groove connected with the flow channel layer protrudes inwards relative to the inlet of the flow channel.

According to one embodiment of the present application, the outer wall of the reservoir is cylindrical.

According to an embodiment of the application, the bottom diameter of the liquid storage cavity is D1, the top diameter of the liquid storage cavity is D2, and the volume of the liquid storage cavity is V, so that the following conditions are satisfied: d1 is less than or equal to 2.5mm and less than or equal to 3mm, D2 is less than or equal to 1mm and less than or equal to 2.5mm, and V is less than or equal to 5 mu L and less than or equal to 100 mu L.

According to one embodiment of the application, the wall thickness of the liquid storage groove is B, and the thickness of the liquid storage groove is more than or equal to 0.5mm and less than or equal to 2mm.

According to one embodiment of the application, the liquid storage groove and the runner layer are integrally injection molded.

According to one embodiment of the application, the reservoir is made of a transparent material.

In a second aspect, the present application provides a microfluidic chip comprising:

a flow channel structure as in any one of the above;

and the film layer is adhered to the back surface of the flow channel layer.

According to the microfluidic chip, through the arrangement of the flow channel structure and the thin film layer, PCR amplification and related detection of sample liquid are realized, and operation steps are greatly simplified, so that detection efficiency is remarkably improved.

According to one embodiment of the application, the wall thickness of one end of the liquid storage groove connected with the flow channel layer is B1, and the thickness of the microfluidic chip is A, so that B1/A is less than or equal to 1.2.

Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the application.

Drawings

The foregoing and/or additional aspects and advantages of the present application will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings, wherein:

fig. 1 is a schematic structural diagram of a flow channel structure of a microfluidic chip according to an embodiment of the present disclosure;

fig. 2 is a second schematic structural diagram of a flow channel structure of a microfluidic chip according to an embodiment of the present disclosure;

fig. 3 is a schematic structural diagram of a sealing cover of a microfluidic chip according to an embodiment of the present application;

fig. 4 is a second schematic structural diagram of a sealing cover of the microfluidic chip according to the embodiment of the present application;

fig. 5 is a schematic structural diagram of a microfluidic chip according to an embodiment of the present application.

Reference numerals:

flow channel structure 100, flow channel layer 110, flow channel 111, liquid storage tank 120, liquid storage cavity 121;

sealing cover 200, plug body 210, groove 211, flange 220, rigid tube 230;

sample fluid 300.

Detailed Description

Embodiments of the present application are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary only for the purpose of explaining the present application and are not to be construed as limiting the present application.

The application discloses a flow channel structure 100 of a microfluidic chip.

The flow channel structure 100 of the microfluidic chip according to an embodiment of the present application is described below with reference to fig. 1 to 2.

In some embodiments, as shown in fig. 1, the flow channel structure 100 includes: a flow channel layer 110 and a reservoir 120.

The back surface of the runner layer 110 is provided with a runner 111.

The flow channel layer 110 may be used to accommodate micro droplets generated by the sample solution 300, and the flow channel layer 110 may be made of a polymer material, where the polymer may include PDMS (polydimethylsiloxane), PMMA (polymethyl methacrylate), or silicone rubber, for example, in some embodiments, the flow channel layer 110 is made of silicone rubber.

In actual implementation, as shown in fig. 1, the flow channel 111 may be processed from the back surface of the flow channel layer 110, and the inlet of the flow channel 111 may be disposed on the front surface of the microfluidic chip, and the micro droplets may be injected from the inlet of the flow channel 111 and flow into the flow channel 111 on the back surface of the flow channel layer 110.

Through the arrangement of the runner layer 110 and the runner 111, the injection of micro-droplets into the chip is realized, and preconditions are provided for the subsequent PCR amplification reaction and detection of the droplets.

The liquid storage tank 120 is located on the front surface of the runner layer 110, and the liquid storage tank 120 and the runner layer 110 are integrally formed, the liquid storage tank 120 is provided with a liquid storage cavity 121, and the liquid storage cavity 121 is communicated with the inlet of the runner 111.

The reservoir 120 may be used to store the sample solution 300 and provide a receiving environment for a PCR (Polymerase Chain Reaction ) reaction system of the sample solution 300, as shown in fig. 1-2, the reservoir 121 may be a hole disposed at the center of the reservoir 120, and the reservoir 121 extends through the reservoir 120, an upper opening of the reservoir 121 may be used to inject the sample solution 300, and a lower opening of the reservoir 120 may be in communication with an inlet of the flow channel 111 in the flow channel layer 110.

It will be appreciated that, as shown in fig. 1-2, the sample solution 300 may be injected into the reservoir 121 from the upper opening of the reservoir 120, because the size of the lower opening of the reservoir 120 and the size of the inlet of the flow channel 111 are both in the micrometer scale, the sample solution 300 is difficult to easily permeate into the flow channel layer 110 in a free state, the upper opening of the reservoir 120 may be sealed after the injection of the sample solution 300, and the PCR reaction may be performed on the sample solution 300 in the reservoir 121 after the sealing.

By the arrangement of the liquid storage groove 120, the storage of the sample liquid 300 is realized, and the sample liquid 300 is prevented from penetrating into the flow channel 111 of the flow channel layer 110 before being pressurized.

In practical implementation, as shown in fig. 1-2, the sample solution 300 is dripped from the upper opening of the liquid storage tank 120, the sample solution 300 enters the liquid storage cavity 121, after the sample solution 300 is dripped, the upper opening of the liquid storage tank 120 is sealed, gas is injected into the liquid storage cavity 121 after the sealing, that is, the reacted sample solution 300 is applied with air pressure, the air pressure extrudes the reacted sample solution 300 to form micro droplets, the micro droplets are extruded into the flow channel 111 in the flow channel layer 110 through the inlet of the flow channel 111, then the micro droplets in the flow channel 111 are subjected to on-chip PCR amplification, and after the on-chip PCR reaction is finished, the chip reading can be performed.

In the related art, after the runner layer and other components are integrated and bonded, the liquid storage tank is processed by a mechanical or laser method.

However, the microfluidic chip manufactured according to the above-described scheme has an insufficient connection between the flow channel layer 110 and the reservoir 120, which is liable to cause leakage of the sample solution 300 after injection into the reservoir 120.

According to the flow channel structure 100 of the microfluidic chip, through the arrangement of the flow channel layer 110 and the liquid storage tank 120, the structure scheme of integrally forming the liquid storage tank 120 and the flow channel layer 110 is matched, so that the detection efficiency of the microfluidic chip is greatly improved, and meanwhile, the sample cost of the microfluidic chip is reduced.

In some embodiments, as shown in fig. 1, the reservoir 120 and the runner layer 110 may be integrally injection molded.

In actual implementation, plastic raw materials are put into a charging barrel, heated and plasticized to become fluid with high viscosity, namely melt, and the melt is injected into a cavity of a die through a nozzle under high pressure by using a plunger or a screw as a pressurizing tool, and is cooled and solidified and then removed from the die to obtain the integrated liquid storage tank 120 and runner layer 110.

It can be appreciated that in the injection molding process, the thin wall of the runner layer 110 is cooled quickly and the shrinkage is small; the wall thickness of the runner layer 110 is slow to cool down, the shrinkage is large, and the runner layer 110 is provided with the runners 111, so that the wall thicknesses of a plurality of areas of the runner layer 110 are not equal, and the defect of insufficient wall thickness of the runner layer 110 at a plurality of positions can be overcome by the mode of integrally injection molding the liquid storage tank 120 and the runner layer 110.

Through the design of the integrated injection molding, firstly, the defect of insufficient wall thickness of the runner layer 110 is overcome, so that the shrinkage influence on the runner 111 in the chip injection molding process is avoided; secondly, the manufactured liquid storage tank 120 and the runner layer 110 do not need to be processed for multiple times, so that the correction working time of the liquid storage tank 120 and the runner layer 110 is saved, and the manufacturing efficiency of the chip is improved; and finally, no waste is generated in the processing process, so that the waste of molding materials is reduced, and the manufacturing cost of the chip is saved.

In some embodiments, as shown in fig. 1-2, the reservoir 120 may be made of a transparent material.

The material used for the liquid storage tank 120 may include, but is not limited to, PC (polycarbonate), COC (cyclic olefin polymer), or acryl, for example, in some embodiments, the liquid storage tank 120 is made of COC (cyclic olefin polymer).

Through the material selection design of the liquid storage tank 120, the liquid storage tank 120 has excellent transparency, so that the on-chip detection function of a chip can be met, and the temperature cycle of the PCR reaction can be tolerated.

In some embodiments, as shown in fig. 1-2, the reservoir 121 may be frustoconical, and the upper bottom of the reservoir 121 may be in communication with the inlet of the flow channel 111.

As shown in fig. 1-2, the liquid storage cavity 121 may be in a truncated cone shape with an upper bottom area unequal to a lower bottom area, wherein the diameter of the upper bottom of the truncated cone is smaller than that of the lower bottom of the truncated cone, the upper bottom of the truncated cone may be disposed at the lower opening of the liquid storage tank 120, and the lower bottom of the truncated cone may be disposed at the upper opening of the liquid storage tank 120, i.e., the liquid storage cavity 121 visually presents a reverse cone shape with a large upper portion and a small lower portion.

In the related art, the liquid storage cavity of the liquid storage tank is cylindrical, and the upper bottom area is equal to the lower bottom area. However, in the field of digital PCR, the detected sample liquid is less, and the liquid level of the sample liquid is too low due to the cylindrical liquid storage cavity, so that the liquid with small air penetration depth is very easy to reach the flow channel, and thus the subsequently formed micro-droplets contain bubbles.

According to the flow channel structure 100 of the microfluidic chip, due to the design of the truncated cone-shaped liquid storage cavity 121, the liquid level of a sample in the liquid storage tank can reach a certain height under the condition of extremely small sample loading quantity, so that air bubbles are prevented from being introduced into the flow channel 111 when the chip is used.

In some embodiments, as shown in fig. 1-2, the diameter of the upper bottom of the reservoir 121 may be smaller than the diameter of the inlet of the flow channel 111, a portion of the end surface of the reservoir 120 connected to the flow channel layer 110 may protrude inward with respect to the inlet of the flow channel 111, and the upper bottom of the reservoir 121 and the inlet of the flow channel 111 may be disposed concentrically.

In the related art, the diameter of the lower opening of the liquid storage tank is equal to the inlet diameter of the flow channel, i.e. the lower opening of the liquid storage tank is level with the inlet of the flow channel. The inventor of the application finds that when the structure is used, the sample liquid in the liquid storage cavity can flow down to the inlet of the flow channel under the natural state.

In the technical scheme of the application, through the design of the lower opening of the liquid storage tank 120 which is not flush with the inlet of the flow channel 111, larger liquid level tension can be formed at the lower opening of the liquid storage tank 120, so that when no pressure is applied, the sample liquid can basically hover in the liquid storage cavity 121.

In this way, by the design of the size and the position of the liquid storage cavity 121, it is further ensured that the sample liquid 300 cannot permeate into the flow channel 111 of the flow channel layer 110 before generating the micro-droplet, so as not to affect the PCR reaction and the detection result of the subsequent micro-droplet.

In some embodiments, as shown in fig. 1-2, the outer wall of the reservoir 120 may be cylindrical.

It will be appreciated that the reservoir 120 within the reservoir 120 is of inverted frusto-conical shape, and the reservoir 120 is generally cylindrical in shape.

If the reservoir 120 is in the shape of an inverted truncated cone corresponding to the reservoir chamber 121, the area of the end surface of the reservoir 120 connected to the flow path layer 110 is reduced, and the defect of insufficient wall thickness of the flow path layer 110 in the region where the flow path 111 is provided cannot be overcome.

In this way, through the structural design of the liquid storage tank 120, the rigidity of the connection part between the liquid storage tank 120 and the runner layer 110 is increased and the reliability is improved by matching with the size setting of the liquid storage cavity 121; on the other hand, the shrinkage influence on the flow channel 111 in the chip injection molding process is ensured to the greatest extent.

In some embodiments, as shown in fig. 1-2, the bottom diameter of the liquid storage cavity 121 may be D1, the top diameter of the liquid storage cavity 121 may be D2, and the volume of the liquid storage cavity 121 may be V, satisfying: d1 is less than or equal to 2.5mm and less than or equal to 3mm, D2 is less than or equal to 1mm and less than or equal to 2.5mm, and V is less than or equal to 5 mu L and less than or equal to 100 mu L.

For example, in some embodiments, the bottom diameter D1 of the reservoir 121 is 3mm, the top diameter D2 of the reservoir 121 is 1.5mm, the volume V of the reservoir 121 is 15 μL, and the height of the reservoir 121 is 6mm.

The diameter D2 of the upper bottom of the reservoir 121 may also satisfy 2 mm.ltoreq.D2.ltoreq.2.5 mm, e.g., in some embodiments, the diameter D2 of the upper bottom of the reservoir 121 is 2.2mm.

In actual execution, when the sample amount is 1. Mu.L, the height of the sample solution 300 in the liquid storage chamber 121 is 2.2mm, when the sample amount is 2. Mu.L, the height of the sample solution 300 in the liquid storage chamber 121 is 2.8mm, when the sample amount is 3. Mu.L, the height of the sample solution 300 in the liquid storage chamber 121 is 3.2mm, when the sample amount is 4. Mu.L, the height of the sample solution 300 in the liquid storage chamber 121 is 3.5mm, when the sample amount is 5. Mu.L, the height of the sample solution 300 in the liquid storage chamber 121 is 3.7mm, and so on.

In the related art, the liquid storage cavity is cylindrical with the same diameter of the upper opening and the lower opening, for example, the opening diameter of the liquid storage cavity is 3mm, and at this time, the liquid storage cavity can hold 35 mu L of sample. The height of the sample solution in the liquid storage chamber was 0.14mm when the sample amount was 1. Mu.L, 0.28mm when the sample amount was 2. Mu.L, 0.42mm when the sample amount was 3. Mu.L, 0.56mm when the sample amount was 4. Mu.L, 0.7mm when the sample amount was 5. Mu.L, 1.4mm when the sample amount was 10. Mu.L, and so on.

According to the flow channel structure 100 provided by the embodiment of the application, through the size design of the liquid storage cavity 121, on one hand, the consumption of the microfluidic biological sample liquid 300 can be saved to the greatest extent, and the introduction of bubbles when a mechanical pump is introduced into the sample liquid 300 can be reduced; on the other hand, before applying pressure to the reservoir 120, the inverted truncated cone structure may form a certain surface tension, preventing the sample liquid 300 in the reservoir 120 from penetrating into the flow channel 111, so that the operation process is more accurate.

In some embodiments, as shown in FIGS. 1-2, the wall thickness of the reservoir 120 may be B, satisfying 0.5 mm.ltoreq.B.ltoreq.2 mm.

For example, in some embodiments, the wall thickness B of the reservoir 120 is 1mm.

It will be appreciated that when the wall thickness of the reservoir 120 is too great, the associated structure of the sealed reservoir 120 also requires a greater volume, and the amount of manufacturing material required increases accordingly, resulting in unnecessary waste; when the wall thickness of the sump 120 is too small, the contact area between the sump 120 and the associated structure sealing it is too small, resulting in poor sealing.

Through the design of the wall thickness range of the liquid storage tank 120, on one hand, waste of manufacturing materials caused by overlarge wall thickness of the liquid storage tank 120 is avoided, and therefore cost control of chip manufacturing is realized; on the other hand, the phenomenon that the contact area of the sealing part is insufficient due to the fact that the wall thickness of the liquid storage groove 120 is too small is avoided, and therefore tightness between the liquid storage groove 120 and related structures for sealing the liquid storage groove 120 is guaranteed.

The application also discloses a microfluidic chip.

A microfluidic chip according to an embodiment of the present application is described below with reference to fig. 1.

In some embodiments, a microfluidic chip includes: such as any of the flow channel structures 100 and thin film layers described above.

The thin film layer is adhered to the back surface of the runner layer 110.

The thin film layer may be used for protection and insulation of the flow channel layer 110, as shown in fig. 1, the thin film layer may be disposed on a side of the flow channel layer 110 facing away from the reservoir 120, and the thin film layer may block the flow channel 111 located at the back of the flow channel layer 110.

The material of the thin film layer may include, but is not limited to, silicon dioxide, silicon nitride, borophosphosilicate glass, polysilicon, or conductive metal, for example, in some embodiments, silicon dioxide.

The primary method of fabricating the processed film layer may include, but is not limited to, oxidation, chemical vapor deposition, evaporation, sputtering, or the like, such as, in some embodiments, sputtering.

Through the arrangement of the flow channel structure 100 and the thin film layer, the microfluidic chip provided by the embodiment of the application realizes PCR amplification and related detection of the sample liquid 300, and greatly simplifies the operation steps, thereby remarkably improving the detection efficiency.

In some embodiments, as shown in FIG. 1, the wall thickness of the end of the reservoir 120 connected to the flow channel layer 110 is B1, and the thickness of the microfluidic chip is A, where B1/A is less than or equal to 1.2.

For example, in some embodiments, the wall thickness B1 of the end of the reservoir 120 connected to the flow channel layer 110 is 1.2mm and the thickness a of the microfluidic chip is 2mm.

In this way, through the design of the thickness range of the lower opening of the liquid storage tank 120 and the thickness range of the chip, the thickness difference between the liquid storage tank 120 and the chip is ensured to be in a proper range, so that deformation caused by solidification of materials with different thicknesses in an injection molding process is reduced.

The application also discloses a sealing cover 200 of the microfluidic chip.

The sealing cap 200 of the microfluidic chip according to the embodiment of the present application is described below with reference to fig. 3 to 5.

In some embodiments, as shown in fig. 3-5, the seal cap 200 includes: a plug body 210 and a rigid tube 230.

The plug body 210 is used for being plugged into the liquid storage groove 120 of the flow channel structure 100 of the microfluidic chip, and the plug body 210 is assembled with the liquid storage groove 120 in a sealing way.

The plugs 210 may be used to block the notches of the reservoirs 120, and the number of plugs 210 may be 1 or more, where a plurality represents 2 or more, for example, in some embodiments, as shown in fig. 3-5, 3 plugs 210 are provided, 3 plugs 210 respectively correspond to 3 reservoirs 120, and 3 plugs 210 are integrated on one sealing cover 200.

As shown in fig. 3-5, the opening of the liquid storage tank 120 is circular, correspondingly, the cross section of the plug body 210 may also be circular, the plug body 210 may abut against the inner wall of the liquid storage tank 120, the plurality of plug bodies 210 may be connected through integral molding, and the sizes of the plurality of plug bodies 210 may be different to match with the liquid storage tanks 120 with different calibers.

It will be appreciated that the plug 210 may form an interference fit with the inner wall of the reservoir 120 to seal the reservoir 120, and after sealing, the sample fluid 300 may undergo a PCR amplification reaction within the reservoir 120.

By the arrangement of the plug body 210, the reservoir 120 of the flow channel structure 100 of the microfluidic chip is sealed, and a closed reaction environment is provided for the PCR reaction of the sample liquid 300.

The rigid tube 230 penetrates the stopper body 210, and an air passage is provided in the rigid tube 230.

The rigid tube 230 may be used to facilitate gas injection into the reservoir 120, and the rigid tube 230 may be made of a metal material, which may include aluminum alloy, stainless steel, zinc alloy, or titanium alloy, etc., for example, in some embodiments, the rigid tube 230 is made of aluminum alloy.

As shown in fig. 5, the rigid tube 230 may be a hollow long tube, the hollow portion inside the rigid tube 230 may be an air passage, the air passage may penetrate through the whole rigid tube 230, one end of the air passage may be in communication with the outside, and the other end of the air passage may be in communication with the inside of the liquid storage tank 120.

It will be appreciated that the sample solution 300 may be injected into the liquid storage cavity 121 from the upper opening of the liquid storage tank 120, because the size of the lower opening of the liquid storage tank 120 and the size of the inlet of the flow channel 111 are both in the micrometer scale, the sample solution 300 is difficult to easily permeate into the flow channel layer 110 in a free state, and the gas is injected into the liquid storage tank 120, that is, the gas pressure is applied to the sample solution 300 in the liquid storage tank 120, and the gas pressure presses the sample solution 300 into the flow channel 111 of the flow channel structure 100 of the microfluidic chip, and the sample solution 300 pressed into the flow channel 111 forms micro droplets.

By the arrangement of the rigid tube 230, the injection of the external gas into the liquid storage tank 120 of the flow channel structure 100 of the microfluidic chip is realized, and the subsequent process of forming micro droplets by the sample liquid 300 is pushed.

In actual implementation, the sample solution 300 is dropped into the reservoir 120, and then the inlet of the reservoir 120 is blocked by the sealing cover 200, wherein the plug body 210 of the sealing cover 200 is stopped against the inner wall of the reservoir 120, after the reservoir 120 is sealed by the sealing cover 200, the rigid tube 230 can be connected with an external air pump, the air pump can pump air into the reservoir 120 through the air channel in the rigid tube 230, the air presses the sample solution 300 in the reservoir 120 into the flow channel 111 of the flow channel structure 100 of the microfluidic chip, the sample solution 300 pressed into the flow channel 111 is in a droplet state, then the micro droplets in the flow channel 111 are subjected to on-chip PCR amplification, and the chip is read after the on-chip PCR reaction is finished.

According to the sealing cover 200 of the microfluidic chip, through the arrangement of the plug body 210 and the rigid tube 230, on one hand, the sealing cover 200 plays a good sealing role on the liquid storage tank 120 so as to prevent volatilization of an oil-water system, and on the other hand, the sealing cover 200 keeps pressure balance at the inlet and the outlet of the microfluidic chip, so that PCR reaction of micro liquid drops is more stable and reliable.

In some embodiments, as shown in fig. 5, the ends of the rigid tube 230 may be flush with the ends of the plug body 210, respectively.

It can be understood that the end of the rigid tube 230 connected with the air pump may be flush with the corresponding end surface of the plug body 210, so that the air pump can be conveniently contacted and connected with the end surface of the plug body 210 directly, and meanwhile, the area of the connecting surface of the air pump and the plug body 210 can be increased; the end of the rigid tube 230 facing away from the air pump may also be flush with the corresponding end surface of the plug body 210, so that direct contact between the rigid tube 230 and the sample liquid 300 may be avoided.

Thus, by the size design of the rigid tube 230, on one hand, the area of the connection surface between the air pump and the plug body 210 is increased, so that the reliability of the connection between the air pump and the plug body 210 is improved; on the other hand, contact between the sample liquid 300 and the rigid tube 230 is prevented, thereby reducing corrosion of the sample liquid 300 to the rigid tube 230 and further prolonging the service life thereof.

In some embodiments, as shown in fig. 4-5, the first end surface of the plug body 210 may be provided with a groove 211, and the first end surface of the plug body 210 may be an end surface facing the air tap of the air pump.

As shown in fig. 5, the groove 211 may be concentrically fitted with the rigid tube 230, i.e., the groove 211 and the rigid tube 230 may be symmetrical with respect to the same symmetry axis, and the bottom of the groove 211 may be flush with the end surface of the reservoir 120.

In actual implementation, the groove 211 of the plug 210 may be tightly matched with an air pump, the air tap of the air pump may be connected with the rigid tube 230 of the sealing cover 200, the air pump starts to pump air from the air tap into the rigid tube 230, and the air may then enter the liquid storage tank 120 through the rigid tube 230.

By the arrangement of the grooves 211, the concave-convex matching of the air pump and the plug body 210 is realized, and on one hand, the reliability of the joint of the air pump and the plug body 210 is enhanced; on the other hand, the pumping efficiency of the air pump to the sample liquid 300 in the liquid storage tank 120 is improved.

In some embodiments, as shown in fig. 4-5, the recess 211 may be frustoconical and the frustoconical upper base may be located near one end of the rigid tube 230.

As shown in fig. 4 to 5, the groove 211 may be in a truncated cone shape with an upper bottom area unequal to a lower bottom area, wherein the diameter of the upper bottom of the truncated cone is smaller than that of the lower bottom of the truncated cone, the upper bottom of the truncated cone is disposed at the bottom of the groove 211, and the lower bottom of the truncated cone is disposed at the upper opening of the groove 211, i.e., the groove 211 visually presents a reverse taper shape with a large upper part and a small lower part.

Thus, by the design of the shape of the groove 211, firstly, the connection between the air pump and the sealing cover 200 is more compact, and the air leakage phenomenon during inflation is reduced; and secondly, the air pump is convenient to install and disassemble, and the operation is convenient.

In some embodiments, as shown in fig. 3-5, the seal cap 200 may further include: and a flange 220.

The flange 220 may be coupled to the plug body 210, and the flange 220 may define a gap with the plug body 210, and the flange 220 may be configured to conform to an outer wall of the reservoir 120.

As shown in fig. 3-5, the opening of the liquid storage tank 120 is circular, correspondingly, the cross section of the flange 220 may also be circular, the flange 220 may be integrally formed with the plug body 210, and the gap between the flange 220 and the plug body 210 may be matched with the edge of the liquid storage tank 120.

In actual implementation, the plug body 210 may abut against the inner wall of the liquid storage tank 120, the flange 220 may abut against the outer wall of the liquid storage tank 120, and the groove edge of the liquid storage tank 120 may be tightly screwed into between the plug body 210 and the flange 220.

Through the arrangement of the flange 220 and the arrangement of the plug body 210, the inner wall and the edge of the liquid storage tank 120 to be sealed can be well encapsulated, so that the volatilization of the sample liquid 300 can be better prevented.

In some embodiments, as shown in fig. 3 and 5, the length of plug body 210 may be greater than the length of flange 220.

In other words, the height of the contact surface between the plug body 210 and the reservoir 120 is greater than the height of the contact surface between the flange 220 and the reservoir 120.

In actual implementation, in the process of sealing the opening of the liquid storage tank 120 by the sealing cover 200, the sealing cover 200 is pressed downwards, so that frictional resistance between the plug body 210 and the inner wall of the liquid storage tank 120 needs to be overcome, and meanwhile, frictional resistance between the flange 220 and the outer wall of the liquid storage tank 120 needs to be overcome, and the shorter length of the flange 220 can reduce the path for overcoming resistance when the sealing cover 200 moves downwards; similarly, in the process of removing the sealing cover 200, the sealing cover 200 is pulled upwards, and the frictional resistance between the plug body 210 and the inner wall of the liquid storage tank 120 needs to be overcome, and meanwhile, the frictional resistance between the flange 220 and the outer wall of the liquid storage tank 120 needs to be overcome, so that the distance of overcoming the resistance when the sealing cover 200 moves upwards can be reduced due to the shorter length of the flange 220.

Through the design of the dimensions of the plug body 210 and the flange 220, the difficulty in installing and dismantling the sealing cover 200 is reduced, and the time consumed in installing and dismantling the sealing cover 200 is reduced, so that the detection efficiency of the sample liquid 300 is improved.

In some embodiments, as shown in fig. 3 and 5, the plug body 210 may be a solid structure.

As shown in fig. 3, the plug body 210 may be a solid round table, the flange 220 may be a hollow ring, and the plug body 210 and the flange 220 may be concentric circles, that is, the centers of the circles of the plug body 210 and the flange 220 are at the same position.

It can be appreciated that the solid structure of the plug body 210 can fill the opening of the liquid storage tank 120, the plug body 210 forms an interference fit with the opening of the liquid storage tank 120 through the filling of the volume of the plug body 210, and when the plug body 210 seals the opening of the liquid storage tank 120, the inner wall of the liquid storage tank 120 applies a radial extrusion force to the plug body 210, so as to achieve a good sealing effect.

Through the arrangement of the solid structure, the filling effect of the sealing cover 200 on the opening of the liquid storage tank 120 is realized, and the extrusion resistance and durability of the sealing cover 200 are enhanced, so that the PCR amplification reaction of liquid drops is more stable.

In some embodiments, as shown in fig. 3 and 5, the plug body 210 may be made of an elastomeric material having a hardness of 30-60.

For example, in some embodiments, the plug body 210 is made of an elastomeric material having a durometer of 50.

It will be appreciated that an elastomeric material with excessive hardness may cause wear or greater damage to the reservoir 120 during frequent installation and removal of the material; while an elastic material having too low a hardness has limited strength and wear resistance, which affects the life and sealing effect of the sealing cap 200.

By selecting the material of the plug body 210, on one hand, the sealing cover 200 is ensured to have good wear resistance and antifriction property, and is convenient for related operators to operate; on the other hand, the processing is convenient and the cost is low while ensuring good industrial performance and mechanical performance.

The application also discloses another microfluidic chip.

A microfluidic chip according to an embodiment of the present application is described below with reference to fig. 1 to 5.

In some embodiments, as shown in fig. 5, the microfluidic chip includes: a flow path structure 100 and a seal cap 200 as any one of the above.

The flow channel structure 100 comprises a flow channel layer 110 and a liquid storage groove 120, wherein the flow channel layer 110 is provided with a flow channel 111, the liquid storage groove 120 is provided with a liquid storage cavity 121, and the liquid storage cavity 121 is communicated with an inlet of the flow channel 111.

The specific configuration of the flow channel structure 100 is described in detail in the above embodiments, and will not be described here again.

The plug body 210 is plugged into the liquid storage cavity 121 of the liquid storage groove 120, and the sealing cover 200 is assembled with the liquid storage groove 120 in a sealing way.

The sealing cover 200 can be used for sealing a droplet generation process and a PCR reaction process of a microfluidic chip, in actual implementation, the plug body 210 and the flange 220 seal the opening of the liquid storage tank 120 together, the air pump injects air into the liquid storage cavity 121 of the liquid storage tank 120 through the rigid tube 230, so that pressure acts on the liquid surface and generates a certain speed to generate micro droplets, the micro droplets enter the flow channel 111 of the flow channel structure 100, then on-chip PCR amplification of the micro droplets is performed, and the detection result is checked after the PCR reaction is finished.

According to the microfluidic chip provided by the embodiment of the application, through the arrangement of the flow channel structure 100 and the sealing cover 200, on one hand, volatilization of the sample liquid 300 is reduced, so that the consumption of the sample liquid 300 and the requirement on the sample liquid 300 are greatly reduced; on the other hand, the whole PCR reaction process of the micro-droplets is sealed, and the pressures at the inlet and the outlet of the chip are balanced, so that pollution is reduced, and the detection result of the sample liquid 300 is more accurate.

In some embodiments, as shown in fig. 1-5, the reservoir 121 may be frustoconical, and the upper bottom of the reservoir 121 may be in communication with the inlet of the flow channel 111; the plug body 210 may be in the shape of a truncated cone; the included angle between the bus bar of the plug 210 and the bottom surface may be greater than the included angle between the bus bar of the reservoir 121 and the bottom surface.

As shown in fig. 5, the liquid storage chamber 121 may have an inverted truncated cone shape, the diameter of the upper bottom of the liquid storage chamber 121 is smaller than the diameter of the lower bottom of the liquid storage chamber 121, the upper bottom of the liquid storage chamber 121 may be disposed at the lower opening of the liquid storage tank 120, and the lower bottom of the liquid storage chamber 121 may be disposed at the lower opening of the liquid storage tank 120; the plug body 210 may also be in an inverted truncated cone shape, where the diameter of the upper bottom of the plug body 210 is smaller than the diameter of the lower bottom of the plug body 210, and the upper bottom of the plug body 210 may be disposed at one end near the upper bottom of the liquid storage cavity 121, and the lower bottom of the plug body 210 may be disposed at the lower bottom of the liquid storage cavity 121.

It will be appreciated that if the included angle between the bus bar of the reservoir 121 and the bottom surface is equal to the included angle between the bus bar of the plug 210 and the bottom surface, the reservoir 121 and the plug 210 are just engaged, the plug 210 is not compressed, or the plug 210 is slightly compressed; if the included angle between the bus and the bottom surface of the plug body 210 is greater than the included angle between the bus and the bottom surface of the liquid storage cavity 121, the plug body 210 is compressed to a greater extent by applying a greater extrusion force to the plug body 210 from the inner wall of the liquid storage cavity 121 after the plug body 210 is pressed into the liquid storage cavity 121.

Through the arrangement of the liquid storage cavity 121 and the inclination angle of the plug body 210, the plug body 210 of the sealing cover 200 is expanded at a certain angle relative to the liquid storage cavity 121, so that a closer fit is formed between the plug body 210 and the inner wall of the liquid storage tank, the sealing effect of the sealing cover 200 is optimized, and the accuracy of the detection result after the micro-liquid drops are subjected to PCR reaction is further ensured.

In some embodiments, the chip may include: a film layer, a flow channel structure 100 such as any of the above, and a seal cap 200 such as any of the above.

The flow channel structure 100 may include a flow channel layer 110 and a liquid storage tank 120, the flow channel layer 110 may be provided with a flow channel 111, the liquid storage tank 120 may have a liquid storage cavity 121, and the liquid storage cavity 121 may be in communication with an inlet of the flow channel 111.

The thin film layer may be disposed on the back surface of the runner layer 110, and the thin film layer may be used for protection and insulation of the runner layer 110.

The plug body 210 of the sealing cover 200 can be plugged into the liquid storage cavity 121 of the liquid storage tank 120, and the sealing cover 200 and the liquid storage tank 120 can be assembled in a sealing manner.

The specific configurations of the flow channel structure 100, the film layer and the sealing cover 200 are described in detail in the above embodiments, and are not described herein again.

According to the microfluidic chip provided by the embodiment of the application, through the arrangement of the film layer, the flow channel structure 100 and the sealing cover 200, on one hand, the detection efficiency of the microfluidic chip is improved, and the sample cost of the microfluidic chip is reduced; on the other hand, the pollution to the sample is reduced, and the error rate of the detection result is reduced.

The terms first, second and the like in the description and in the claims, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged, as appropriate, such that embodiments of the present application may be implemented in sequences other than those illustrated or described herein, and that the objects identified by "first," "second," etc. are generally of a type and not limited to the number of objects, e.g., the first object may be one or more. Furthermore, in the description and claims, "and/or" means at least one of the connected objects, and the character "/", generally means that the associated object is an "or" relationship.

In the description of the present application, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "top," "bottom," "inner," "outer," "axial," "radial," "circumferential," and the like indicate an orientation or positional relationship based on that shown in the drawings, merely for convenience of description and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be configured and operated in a particular orientation, and therefore should not be construed as limiting the present application.

In the description of the present application, "a first feature", "a second feature" may include one or more of the features.

In the description of the present application, the meaning of "plurality" is two or more.

In the description of this application, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, and may also include the first and second features not being in direct contact but being in contact by another feature therebetween.

In the description of this application, a first feature "above," "over" and "above" a second feature includes a first 5 feature directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature.

In the description of the present specification, reference is made to the terms "one embodiment," "some embodiments," "illustrative embodiments," and the like,

The description of "an example," "a particular example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In the present specification, the above-mentioned

The schematic representations of the terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials 0, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that: many changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the application, the scope of which is defined by the claims and their equivalents.

Claims (10)

1. A flow channel structure of a microfluidic chip, comprising:

the back of the flow channel layer is provided with a flow channel;

the liquid storage tank is positioned on the front face of the runner layer and integrally formed with the runner layer, and is provided with a liquid storage cavity which is communicated with an inlet of the runner.

2. The flow channel structure of the microfluidic chip according to claim 1, wherein the liquid storage cavity is in a shape of a truncated cone, and an upper bottom of the liquid storage cavity is communicated with an inlet of the flow channel.

3. The flow channel structure of the microfluidic chip according to claim 2, wherein a diameter of an upper bottom of the liquid storage chamber is smaller than a diameter of an inlet of the flow channel, and a portion of an end surface of the liquid storage tank connected to the flow channel layer protrudes inward with respect to the inlet of the flow channel.

4. The flow channel structure of the microfluidic chip according to claim 2, wherein the outer wall of the reservoir is cylindrical.

5. The flow channel structure of the microfluidic chip according to claim 2, wherein the bottom diameter of the liquid storage cavity is D1, the top diameter of the liquid storage cavity is D2, and the volume of the liquid storage cavity is V, so that: d1 is less than or equal to 2.5mm and less than or equal to 3mm, D2 is less than or equal to 1mm and less than or equal to 2.5mm, and V is less than or equal to 5 mu L and less than or equal to 100 mu L.

6. The flow channel structure of the microfluidic chip according to claim 1, wherein the wall thickness of the liquid storage tank is B, and B is more than or equal to 0.5mm and less than or equal to 2mm.

7. The flow channel structure of a microfluidic chip according to any one of claims 1-6, wherein said reservoir and said flow channel layer are integrally injection molded.

8. The flow channel structure of a microfluidic chip according to any one of claims 1 to 6, wherein the reservoir is made of a transparent material.

9. A microfluidic chip, comprising:

the flow channel structure as claimed in any one of claims 1 to 8;

and the film layer is adhered to the back surface of the flow channel layer.

10. The microfluidic chip according to claim 9, wherein the wall thickness of the end of the liquid storage groove connected with the flow channel layer is B1, and the thickness of the microfluidic chip is A, and B1/A is less than or equal to 1.2.

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