An amplification device for uniformly dividing microfluidic volume

Abstract

This utility model discloses an amplification device for uniformly dividing microfluidic volumes, comprising a flow divider, several outlet chambers of equal volume, and a sealing layer. The flow divider includes a top plate, an inlet channel, and microchannels connecting the inlet channel and each outlet chamber, with the microchannels having equal volumes. The sealing layer covers the top plate, forming a closed space between the microchannels and the outlet chambers. Liquid is pushed into the inlet channel, causing the flow rate to be proportionally divided into the outlet chambers. This device solves the problem in existing microfluidics technologies where flow rate division accuracy is easily affected by external factors, and the adoption of other solutions increases system complexity and cost. It achieves the beneficial effects of simplified design and reduced cost.

Description

Technical Field

[0001] The present application relates to the technical field of microfluidic devices, and specifically to an amplification device for uniformly dividing the volume of microfluids. Background Art

[0002] In the field of microfluidics, it is often desirable to divide the fluid of a single microfluidic channel into individual fluid branches in a controlled manner. However, this operation can be extremely challenging and inevitably results in uneven and uncontrolled fluid flow. Microfluidic channels must be manufactured to extremely high precision because even slight defects can cause differences in flow resistance along the channel. When dividing a single flow into multiple fluids, microfluidic splitters often use bifurcated channels to ensure that the lengths of the microfluidic channels are equal.

[0003] For example, Chinese patent CN102389730A discloses a double emulsion preparation chip, which is manufactured from a substrate with a three-layer structure, wherein an internal fluid channel is arranged on the inner side of the upper surface of the substrate, an external fluid channel is arranged on the inner side of the lower surface of the substrate, and an intermediate fluid channel is arranged between the external fluid channel and the internal fluid channel, wherein the internal fluid channel has a first fractal tree-like microchannel, and the intermediate fluid channel has a second fractal tree-like microchannel, and the number of branches, crossing angles, and channel lengths of the internal fluid channel and the intermediate fluid channel are all consistent, and the order n is an integer greater than 2 and less than 10.

[0004] However, even with precisely machined channels, bubbles, imperfections, and surface contamination within the microfluidic channels can cause flow along a channel to be blocked, resulting in significant changes in flow along otherwise identical channels. Flow control using valves and sensors can ensure that flow is divided correctly, but this approach adds complexity and cost to the overall system. Utility Model Content

[0005] The purpose of the utility model is to provide an amplification device for uniformly dividing the volume of microfluids in view of the defects of the above-mentioned prior art.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] An amplification device for uniformly dividing the volume of a microfluid, comprising a splitter plate, a plurality of outlet chambers of equal volume and a sealing layer;

[0008] The manifold plate comprises a top plate, an inlet channel arranged on the top plate, and a microchannel connecting the inlet channel and the outlet chamber, wherein the volume of the microchannel connecting the inlet channel and each outlet chamber is equal;

[0009] The sealing layer is covered on the top plate, so that the microchannel and the outlet chamber form a closed space. The liquid is pushed into the inlet channel, so that the flow rate is divided into the outlet chamber in proportion to the volume of the outlet chamber.

[0010] As a preferred implementation, the top plate is consistent in shape with the sealing layer.

[0011] As a preferred embodiment, a partition line is provided in the middle of the cavity of the outlet chamber, the surface of the diverter plate structure above the partition line is a hydrophilic surface, and the diverter plate structure below the partition line is a transparent material. The hydrophilic surface can be achieved by using a hydrophilic material, or by performing a surface hydrophilic treatment in an existing manner to obtain a hydrophilic surface. The provision of a hydrophilic surface above the partition line can enable the liquid to be divided to flow in more effectively, and the provision of a transparent material below the partition line can enable unimpeded fluorescence analysis after the amplification reaction.

[0012] As a preferred embodiment, the hydrophilic surface is made of frosted material, or is provided with leather grain or coating.

[0013] As a preferred embodiment, the microchannel gradually widens its diameter at the connection with the outlet chamber to form a variable diameter portion. The variable diameter portion can widen the channel, reduce liquid tension, and facilitate the liquid to reach the bottom of the outlet chamber.

[0014] As a preferred embodiment, the diameter-changing portion is a semicircle with a diameter smaller than the outlet chamber opening, and the center of the semicircle is at the edge of the outlet chamber opening.

[0015] As a preferred embodiment, the top plate bottom is provided with a positioning reinforcement rib between the outlet chamber and the inlet channel. The positioning reinforcement rib can prevent warping after injection molding and can be used for positioning during later use.

[0016] As a preferred embodiment, the diverter plate and the sealing layer are both made of thermoplastic materials; preferably, polypropylene (PP) is used, and the use of PP material is conducive to cost saving.

[0017] As a preferred embodiment, the sealing layer and the top plate are connected by glue; preferably, double-sided adhesive is used for bonding, and the double-sided adhesive is provided with an opening corresponding to the size and position of the top entrance of the outlet chamber. The use of double-sided adhesive can economically form a closed space under a micro-pressure environment.

[0018] As a preferred embodiment, the top plate is further provided with a guide portion, which is a triangular prism structure. A guide groove can be correspondingly provided in the microfluidic machine / cartridge to which the amplification device is applied, and the guide portion can be connected to the microfluidic machine / cartridge through the guide groove, so that the device can move in the guide groove.

[0019] As a preferred embodiment, the inlet channel is arranged in the guide portion, and the inlet channel is connected with the microchannel through the guide portion.

[0020] When the device of the utility model is used, the outlet chamber can be used for polymerase chain reaction of liquid to analyze several biomarkers in the liquid, or for immunoassay reaction of liquid to analyze several biomarkers in the liquid.

[0021] The utility model has the following beneficial effects:

[0022] The utility model provides a simple method that allows a single-channel fluid to be accurately divided into multiple fluid branches in a controllable manner. It relies on a gas buffer chamber formed by dispersed, unconnected outlet chambers, combined with the outlet of each fluid, and the microchannel and outlet chamber are both closed, rather than connected to the atmosphere in an open form. The outlet is designed and connected to the flow path of each fluid, so that when the fluid is pumped into the closed buffer chamber, the gas is compressed and the pressure increases. This increase in pressure creates an increasing fluid resistance, which is proportional to the volume of fluid pumped into it. Therefore, if one channel is blocked, preventing the fluid, the pressure in the other unblocked chamber will increase until the blockage is overcome. This design brings about a natural balance between pressure and flow, so this can be simply achieved by designing the closed chamber to have the correct volume to achieve the required fluid volume along each channel. The overall design of the utility model effectively reduces the complexity of the microfluidic division system and reduces costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of a three-dimensional structure of an embodiment of the present application;

[0024] Figure 2 This is a schematic diagram of the three-dimensional structure of an embodiment of a diverter plate of the present application;

[0025] Figure 3 This is a front view schematic diagram of an embodiment of a diverter plate of the present application;

[0026] Figure 4 This is a top view schematic diagram of an embodiment of a diverter plate of the present application;

[0027] Among them, 1-diverter plate, 11-top plate, 111-microchannel, 1111-diameter reducing portion, 12-inlet channel, 13-outlet chamber, 14-positioning reinforcement ribs, 15-guide portion, 2-sealing layer. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0029] In the embodiment, the sealing layer is a functional structure for sealing the microchannel and the outlet chamber, and may be sealed by a membrane, a double-sided tape, or a cover plate.

[0030] Example 1

[0031] like Figures 1 to 4 An amplification device for uniformly dividing the volume of microfluids is shown, comprising a manifold plate 1, eight outlet chambers 13 of equal volume and a sealing layer 2, wherein the manifold plate 1 comprises a top plate 11, an inlet channel 12 arranged on the top plate 11 and a plurality of microfluidic channels 111, and the volume of each outlet chamber is 20 microliters.

[0032] In this embodiment, one side of the top plate 11 (the outlet chamber side) is rectangular, and the other side (the inlet channel side) is generally triangular. There are a number of microchannels 111 on the top plate 11 to connect the eight outlet chambers 13 and the inlet channel 12. In this embodiment, the microchannel 111 is a tree-shaped bifurcated structure connecting the eight outlet chambers 13 and the inlet channel 12, which can reduce the total length of the microchannel 111. There is a shared microchannel 111 between different outlet chambers 13, which further reduces the volume error of the microchannel 111 caused by process problems.

[0033] In this embodiment, the closed layer 2 and the top surface of the top plate 11 have the same shape, and the closed layer 2 is covered on the top plate 11 of the manifold 1, so that the microchannel 111 and the outlet chamber 13 form a closed space, and the volume of the closed space formed by each microchannel 111 and the outlet chamber 13 is equal. There may be errors in the volume due to process problems, but the use of the compressed air principle can greatly reduce the problem of uneven fluid division caused by volume errors. Specifically, after the gas is compressed, the compressed volume is similar, the back pressure will be similar, and the resistance to liquid inflow is almost the same. Therefore, the volume of the inflowing liquid is also equal to the maximum extent, and in the case of channel leakage (microfluidic chips are usually open outlet sample pools, or vents are set on the microchannels), the gas pressure is uneven, and it is likely that a large amount of liquid unevenness will occur.

[0034] The sealing layer 2 is bonded to the top plate 11 of the diverter plate 1 by means of adhesive connection. A preferred embodiment is that the sealing layer 2 is bonded to the top plate 11 by means of double-sided adhesive tape, and an opening corresponding to the size and position of the outlet chamber opening is required on the double-sided adhesive tape. The use of double-sided adhesive tape can economically form a closed space under a micro-pressure environment, which also meets our requirements for reducing costs. Alternatively, other suitable sealing methods can be used to bond the sealing layer 2 to the top plate 11.

[0035] In order to achieve a better hydrophilic effect, a partition line 131 is set in the middle of the cavity of all outlet chambers 13, the surface above the partition line 131 of the diverter plate 1 is treated with a hydrophilic surface, and the surface below the partition line 131 of the diverter plate 1 is treated with a transparent surface. Considering economy, the diverter plate 1 and the sealing layer 2 in this embodiment are both made of polypropylene. In this embodiment, the hydrophilic surface is frosted, and other treatment methods such as leather grain or coating can also be used, and the material can also be other materials that are easy to be transparent and frosted.

[0036] In order to facilitate the liquid to reach the bottom of the outlet chamber 13 more smoothly, a reducing portion 1111 with a gradually widening diameter is provided at the channel opening when the microchannel 111 is connected to the outlet chamber 13, so that the reducing portion 1111 of the microchannel 111 forms a teardrop-like shape with the outlet chamber opening, and the liquid can have a smooth transition of the cross-sectional area when flowing into the outlet chamber 13. The shape of the reducing portion 1111 can be a rounded arc or a straight line, or it can be a snowman shape, that is, the reducing portion 1111 is a semicircle with a diameter smaller than the outlet chamber opening and the center is near the edge of the outlet chamber opening.

[0037] When in use, the liquid is pushed into the inlet channel 12. For example, the liquid is pumped into the inlet channel 12 by an external pressure source such as a syringe pump. The liquid will be divided into a plurality of outlet chambers 13 in proportion to the volume of the outlet chamber 13 under the pressure balance of the closed space. The number of outlet chambers 13 is greater than one and can be freely set according to actual needs. In this embodiment, the number of outlet chambers 13 is set to eight.

[0038] In order to control the movement of the entire device in the guide groove of the microfluidic machine, a positioning reinforcement rib 14 is further provided between the outlet chamber 13 and the inlet channel 12 on the bottom surface of the top plate 11, and a guide portion 15 is also provided on the inlet channel side of the top plate 11 for connecting with the extraction device. In this embodiment, the guide portion 15 is triangular, and the inlet channel 12 is arranged in the guide portion 15, and the inlet channel 12 is connected to the microchannel 111 through the guide portion 15.

[0039] When the device for dividing the fluid volume in this embodiment is used in a microfluidic machine, the polymerase chain reaction or immunoassay reaction is performed in the outlet chamber 13 to analyze multiple biomarkers in the liquid. The reaction type is not limited to the polymerase chain reaction or immunoassay reaction, and can be a molecular biology or any biochemical reaction system.

Claims

1. An amplification device for uniformly dividing microfluidic volume, characterized in that: It comprises a diverter plate (1), a plurality of outlet chambers (13) of equal volume, and a sealing layer (2); The manifold (1) comprises a top plate (11), an inlet channel (12) arranged on the top plate (11), and a microchannel (111) connecting the inlet channel (12) and the outlet chamber (13), wherein the volume of the microchannel (111) connecting the inlet channel (12) and each outlet chamber (13) is equal; The sealing layer (2) covers the top plate (11), so that the microchannel (111) and the outlet chamber (13) form a closed space.

2. The device according to claim 1, characterized in that The top plate (11) has the same shape as the sealing layer (2).

3. The device according to claim 1, characterized in that A partition line (131) is provided in the middle of the cavity of the outlet chamber (13); the surface of the diverter plate (1) structure above the partition line (131) is a hydrophilic surface, and the diverter plate (1) structure below the partition line (131) is made of a transparent material.

4. The device according to claim 3, characterized in that The hydrophilic surface is made of frosted material, or is provided with leather grain or coating.

5. The device according to claim 1, characterized in that The diameter of the connection between the microchannel (111) and the outlet chamber (13) gradually widens to form a diameter-changing portion (1111).

6. The device according to claim 5, characterized in that The diameter-reducing portion (1111) is a semicircle with a diameter smaller than the outlet chamber opening, and the center of the semicircle is at the edge of the outlet chamber opening.

7. The device according to claim 1, characterized in that The bottom of the top plate (11) is provided with positioning reinforcement ribs (14) between the outlet chamber (13) and the inlet channel (12).

8. The device according to claim 1, characterized in that The diverter plate (1) and the sealing layer (2) are both made of thermoplastic materials.

9. The device according to claim 1, characterized in that The sealing layer (2) and the top plate (11) are connected by glue.

10. The device according to claim 9, characterized in that The sealing layer (2) and the top plate (11) are bonded together using double-sided adhesive tape, and the double-sided adhesive tape is provided with an opening having a size and position corresponding to the top entrance of the outlet chamber (13).

11. The device according to claim 1, characterized in that The top plate (11) is also provided with a guide portion (15), and the guide portion (15) is a triangular prism-shaped structure; the inlet channel (12) is arranged in the guide portion (15), and the inlet channel (12) is connected to the microchannel (111) via the guide portion (15).

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