CN114950584B - A three-dimensional microfluidic channel chip structure and manufacturing method for droplet generation - Google Patents

Abstract

The invention discloses a three-dimensional microchannel chip structure and manufacturing method for droplet generation, including five microchannel layers arranged up and down, the first microchannel layer and the second microchannel layer are used for the first phase and the second microchannel layer. The introduction and diversion of the second phase, the third microchannel layer is provided with matrix-arranged mixing units for the mixing of the first phase and the second phase, and the fourth microchannel process is provided with liquid droplets corresponding to the mixing units one-to-one The releasing unit is used for forming droplets after the first phase and the second phase are mixed, and the fifth microchannel is used for collecting and leading out the droplets. The invention solves the problem that the planar droplet generation chip can produce fewer droplets, and uses three-dimensional micro-channels to reduce the footprint of a single droplet generation module, and can realize several liters of droplets per hour through the matrix arrangement It is expected to achieve an annual output of tons.

Description

A three-dimensional microfluidic channel chip structure and manufacturing method for droplet generation

technical field

The invention belongs to the technical field of micromachining, and in particular relates to a three-dimensional microfluidic channel chip structure and a manufacturing method for liquid drop generation.

Background technique

Traditional droplets are generated by methods such as oscillation, stirring, and ultrasonic emulsification, and are used in the fields of fixed-point transportation of food, cosmetics, and drugs. With the rapid development of biological detection technology and micro-nano materials, micro-nano-sized droplets have begun to be used in the biological detection of micromolecules, the preparation of microcapsules, and the preparation of micro-nano particles.

For the preparation of microcapsules and micro-nanoparticles, how to achieve high-throughput droplet generation is the key to the commercialization of droplet generation chips. The existing planar microfluidic droplet generation chip uses parallel arrays to increase the number of parallel droplet generation modules. Glass-silicon-glass materials have been used. A single planar droplet generation module is 1.4mm long and 80um wide to generate droplets. The size of the droplet is 21-28um, and the output per hour can reach the liter level, and the output of the droplet needs to be further improved.

Contents of the invention

Aiming at the problems and deficiencies in the existing technical solutions, the present invention discloses a structure and a manufacturing method of a three-dimensional array three-dimensional micro-channel chip applied to droplet generation.

In order to achieve the above object, the technical solution of the present invention is:

A three-dimensional microfluidic chip structure for droplet generation,

The beneficial effects of the present invention are:

1) The three-dimensional array microchannel structure and manufacturing method of the microfluidic droplet generation chip are proposed, which solves the problem that the planar microfluidic droplet generation chip can produce fewer droplets, and the three-dimensional microfluidic channel is used to reduce the size of a single chip. The footprint of the droplet generation channel, where the size of the fluid shear can be as small as 1-2um;

2) Through the arrayed three-dimensional micro-channels, the droplet size ranges from 5um to hundreds of um, and can achieve a high output of several liters of droplets per hour, which is expected to achieve the production of tons per year.

Description of drawings

Fig. 1 is a three-dimensional array microfluidic channel structure;

Fig. 2 is a dismantling diagram of a three-dimensional array microfluidic structure;

3 is a cross-sectional view of a three-dimensional array microfluidic structure;

Fig. 4 is a schematic diagram (three-dimensional diagram) of three-dimensional array microfluidic droplet generation;

Fig. 5 is a schematic diagram (sectional view) of three-dimensional array microchannel droplet generation;

Figure 6-12 is a flow chart of the manufacturing process of the three-dimensional array microfluidic channel.

Detailed ways

The present invention will be further explained below in conjunction with the accompanying drawings and specific embodiments. The drawings of the present invention are only schematic diagrams for easier understanding of the present invention, and their specific proportions can be adjusted according to design requirements.

This example discloses a three-dimensional array microchannel chip structure for droplet generation, which can refer to Figures 1-3, including five microchannel layers, from bottom to top are the first microchannel layer 100, The second microchannel layer 200 , the third microchannel layer 300 , the fourth microchannel layer 400 and the fifth microchannel layer 500 .

The first microchannel layer 100 has a first vertical microchannel 101 and a first semi-open planar microchannel 102;

The second microchannel layer 200 has a second vertical microchannel 201;

The third microchannel layer 300 has a second semi-open planar microchannel 301, a third vertical microchannel 302 and a third semi-open planar microchannel 303;

The fourth microchannel layer 400 has a fourth vertical microchannel 401 and a fifth vertical microchannel 402;

The fifth microchannel layer 500 has a fourth semi-open planar microchannel 501 and a sixth vertical microchannel 502 .

If the microchannel chip structure is used to generate oil-in-water droplets, the microchannel wall must be hydrophilic; if water-in-oil droplets are to be generated, the microchannel wall must be hydrophobic. The hydrophilicity and hydrophobicity of microchannels can be achieved by material selection or surface modification of channel walls.

The five microfluidic layers are superposed and connected to form channels for the introduction, diversion and collection of multiple fluids, for example, when the continuous phase fluid and the discrete phase fluid generate droplets:

The first semi-open planar microchannel 102 is divided into a continuous phase dispersion channel 105 and a discrete phase dispersion channel 106 designed with interdigitated fingers, and the first vertical microchannel 101 is divided into a continuous phase dispersion channel 105 and a discrete phase dispersion channel 106. The continuous phase inlet 103 and the discrete phase inlet 104 which are communicated one by one by the flow channel 106; the first microchannel layer 100 is used for the independent entry and transmission of the multiphase fluid;

The second vertical microchannel 201 is divided into a plurality of continuous phase channels 202 and discrete phase channels 203 that communicate with the continuous phase dispersed channel 105 and the discrete phase dispersed channel 106 respectively; the second micro channel layer 200 is used for fluid diversion;

The third microchannel layer 300 forms a number of mixing units arranged in an array, and each mixing unit consists of a second semi-open planar microchannel 301, a third vertical microchannel 302, and a third semiopen planar microchannel from bottom to top. The micro flow channel 303 is composed of a continuous phase flow channel 304 and a discrete phase flow channel 305, which are respectively communicated with the continuous phase flow channel 202 and the discrete phase flow channel 203, so that the continuous phase and the discrete phase enter the mixing unit respectively; In this embodiment, each mixing unit communicates with one discrete phase flow channel 203 and two continuous phase flow channels 202, and the discrete phase flow channel 203 is located in the middle of the two continuous phase flow channels 202; the second semi-open planar micro flow The channel 301 has a meandering flow channel structure to ensure that the dynamic pressure of the continuous phase and the discrete phase entering the mixing unit are consistent as a fluid flow resistance channel; the third semi-open planar micro channel 303 is formed so that the continuous phase channel 304 and the discrete phase The fluids connected by the channel 305 converge.

The fourth vertical micro-channel 401 and the fifth vertical micro-channel 402 are connected up and down to form a droplet discharge unit, and are connected with the aforementioned mixing unit one by one. The fourth vertical micro-channel 401 forms a fluid shear, and the fifth The vertical microchannel 402 is used for droplet release, and the fluids of each mixing unit are mixed to form droplets in the fourth microchannel layer 400; that is, the combination of the third microchannel layer 300 and the fourth microchannel layer 400 A single droplet generating module is formed, and multiple modules are arranged in an array.

The fifth vertical micro-channel 402 and the fourth semi-open planar micro-channel 501 and the sixth vertical micro-channel 502, the fourth semi-open planar micro-channel 501 is used for droplet collection, the sixth vertical micro-channel 502 A droplet outlet is provided for droplet extraction.

For the above-mentioned three-dimensional array microchannel chip structure for droplet generation, the corresponding droplet generation method can refer to Figure 4-Figure 5, the continuous phase and the discrete phase fluid pass through the first microchannel layer and the second microchannel layer respectively. After the channel layer, the third micro channel layer and the fourth micro channel layer, droplets are formed, and the fifth micro channel layer is used to collect and draw out the droplets.

First, the continuous phase fluid 602 passes through the continuous phase inlet 103 , and the discrete phase fluid 601 is introduced into the microchannel through the discrete phase inlet 104 , and then reaches the single droplet generation module through the continuous phase dispersion channel 105 and the discrete phase dispersion channel 106 . Further, flow through the continuous phase flow channel 202 (discrete phase flow channel 203), the second semi-open planar micro flow channel 301, the continuous phase flow channel 304 (discrete phase flow channel 305) to the third semi-open planar micro flow channel After the channels 303 converge, they merge in the fourth vertical micro-channel 401 and pass through the fifth vertical micro-channel 402 to form droplets 603 . Finally, the same positions as the fourth vertical micro-channel 401 and the fifth vertical micro-channel 402 in the array generate droplets and communicate with the fourth semi-open planar micro-channel 501, and pass through the sixth vertical micro-channel 502. A large number of droplets are elicited. By separately controlling the flow rate (ul/min) of the continuous phase and the discrete phase fluid into the chip and the size of the shear point of the microchannel fluid to the scale of several microns/tens of microns, the generation of droplets at the level of 5um to hundreds of um can be achieved.

The fluid flow resistance channels designed in the third microchannel layer 300 ensure that the dynamic pressures of the continuous phase and the dispersed phase entering each droplet generation module in the array are consistent. By arranging tens of thousands of single three-dimensional microfluidic channel array droplet generation modules in an array, several liters of droplets per hour are generated.

With further reference to Figures 6-12, this example also discloses a method for manufacturing a three-dimensional array microfluidic channel chip for generating oil-in-water droplets, including the following steps:

Step 1, as shown in Figure 6(a), the first microchannel layer 100 uses polydimethylsiloxane as the substrate, and the first vertical microchannel 101 is processed on the lower surface 110 by polymer replication molding technology, as shown in the figure The upper surface 120 shown in 6(b) is processed with a first semi-open planar micro-channel 102, and the first vertical micro-channel 101 communicates with the first semi-open planar micro-channel 102, and forms an affinity channel on the micro-channel. water coating;

Step 2, as shown in FIG. 7 , the second microchannel layer 200 uses glass as the substrate, and the second vertical microchannel layer 201 connecting the lower surface 210 and the upper surface 220 can be formed through laser processing technology;

Step 3, as shown in Figure 8(a), the third microchannel layer 300 uses silicon as a substrate, and etches a second semi-open planar microchannel 301 on the lower surface 310 by deep reactive ion etching technology, as shown in the figure 8 (b) and etch out the third semi-open planar micro-channel 303 on the upper surface 320, as shown in Figure 8 (c), process the third semi-open planar micro-channel 303 downwards at the second semi-open planar micro-channel 303 vertical micro-channel 302;

Step 4, as shown in Figure 9(a), the fourth flow channel layer 400 uses glass as a substrate, and after the fifth vertical micro-channel 402 is processed on the upper surface 420 by laser processing technology, as shown in Figure 9(b) As shown, a fourth vertical micro-channel 401 is processed on the lower surface 410;

Step 5, as shown in Figure 10(a), the fifth microchannel layer 500 uses polydimethylsiloxane as the substrate, and the fourth semi-open planar microchannel 501 is processed on the lower surface 510 by polymer replication molding technology , as shown in Figure 10 (b), the upper surface 120 processes the sixth vertical micro-channel 502, and the fourth semi-open planar micro-channel 501 communicates with the sixth vertical micro-channel 502, and forms on the micro-channel Hydrophilic coating;

Step 6, as shown in FIG. 11 , uses a silicon glass anodic bonding process to bond the second channel layer 200 and the fourth micro channel layer 400 on both sides of the third micro channel layer 300 respectively to communicate with the second channel layer 300. Vertical micro-channel layer 201, second semi-open planar micro-channel 301, third vertical micro-channel 302, third semi-open planar micro-channel 303, fourth vertical micro-channel 401 and fifth vertical micro-channel Road 402;

Step 7, as shown in Figure 12, adopts the plasma bonding method on the basis of step 7 to bond the first micro-channel layer 100 on the lower surface of the second micro-channel layer 200, and the fourth micro-channel layer 200 The fifth microchannel layer 100 is bonded to the upper surface of the channel layer 400 to realize the communication between the first vertical microchannel 101 and the sixth vertical microchannel.

The minimum characteristic size of the microchannel can reach 1-2um, and it can also be controlled to a scale of tens or hundreds of microns; the footprint of a single droplet generation module is less than 1mm*50um.

In steps 1 and 5, in addition to polydimethylsiloxane, silicon or glass or Teflon or acrylic or other polymer materials can also be selected for the substrate; in steps 1 and 5, in addition to using polymer replication molding technology, You can choose deep reactive ion etching technology or laser-induced etching rapid prototyping technology or wet etching or hot embossing technology or laser ablation or sandblasting or ultrasonic micromachining or CNC machining and other methods;

Substrate in steps 2 and 4, in addition to using glass as the substrate, silicon or Teflon or acrylic or polydimethylsiloxane or other polymer materials can also be selected; in steps 2 and 4, in addition to using laser processing technology You can choose deep reactive ion etching technology or laser-induced etching rapid prototyping technology or wet etching or hot embossing technology or laser ablation or sandblasting or ultrasonic micromachining or CNC machining and other methods;

In step 3, the substrate can be selected from glass or Teflon or acrylic or polydimethylsiloxane or other polymer materials except that silicon is used as the substrate; in step 3, in addition to using deep reactive ion etching technology, Choose laser-induced etching rapid prototyping technology or wet etching or hot embossing technology or laser ablation or sandblasting or ultrasonic micromachining or CNC machining;

In step 6, in addition to the silicon glass anodic bonding process, thermal bonding or glue bonding or metal interlayer bonding or low temperature bonding technology can also be used.

In step 7, in addition to the plasma bonding method, thermal bonding, glue bonding, metal interlayer bonding, or low-temperature bonding technology can also be used.

The above-mentioned embodiments are only used to further illustrate a three-dimensional array microfluidic channel chip structure and manufacturing method for droplet generation of the present invention, but the present invention is not limited to the embodiments. Any simple modifications, equivalent changes and modifications made in the embodiments all fall within the protection scope of the technical solution of the present invention.

Claims (7)

1. A three-dimensional microfluidic chip structure for droplet generation, characterized in that: it comprises a first microfluidic layer, a second microfluidic layer, a third microfluidic layer, and a fourth microfluidic layer from bottom to top. flow channel layer and the fifth micro flow channel layer; The first microchannel layer has a first vertical microchannel for fluid entry and a first semi-open planar microchannel for fluid dispersion; the first semi-open planar microchannel is divided into interdigitated designs The first phase dispersion flow channel and the second phase dispersion flow channel, the first vertical micro flow channel is divided into the first phase inlet and the second phase flow channel which communicate with the first phase dispersion flow channel and the second phase dispersion flow channel in one-to-one correspondence Entrance; The second microchannel layer has several second vertical microchannels arranged in an array; the first vertical microchannel, the first semi-open planar microchannel and the second vertical microchannel form a mutually independent first The flow channel of the phase and the flow channel of the second phase; The third microchannel layer has several mixing units arranged in an array, and each mixing unit is composed of the second semi-open planar microchannel, the third vertical microchannel and the third semi-open planar microchannel from bottom to top Form; Each mixing unit communicates with the second vertical microchannel of the first phase and the second vertical microchannel of the second phase and is used for mixing the first phase and the second phase; the first phase and the second phase are continuous A phase fluid and a discrete phase fluid, the continuous phase fluid and the discrete phase fluid form droplets through the mixing unit and the droplet discharge unit; the mixing unit communicates with the second vertical microchannel of the two continuous phases and a discrete phase the second vertical microchannel of the discrete phase, and the second vertical microchannel of the discrete phase is located in the middle of the second vertical microchannel of the two continuous phases, the discrete phase and the continuous phase are in the third semi-open planar microflow channel mix in the channel; The fourth microchannel layer has a droplet discharge unit that communicates with the outlet of the mixing unit one by one, and each droplet discharge unit is formed by combining the fourth vertical microchannel and the fifth vertical microchannel; The fifth microchannel layer has a fourth semi-open planar microchannel for converging droplets formed by the droplet releasing unit and a sixth vertical microchannel for droplet extraction. 2. The three-dimensional microfluidic chip structure for droplet generation according to claim 1, characterized in that: the fourth vertical microfluidic channel is connected to the outlet of the mixing unit, and the fourth vertical microfluidic The channels are used to form fluid shearing, and the size range of the fourth vertical micro-channels is 1-100 μm. 3. The three-dimensional microfluidic chip structure for droplet generation according to claim 1, characterized in that: the second semi-open planar microfluidic channel has a meandering channel structure for use as a fluid The flow resistance channel makes the dynamic pressure of the first phase and the second phase uniform when entering the plurality of mixing units arranged in an array. 4. The three-dimensional microfluidic chip structure for droplet generation according to claim 1, characterized in that: the droplet generation module is composed of the mixing unit and the droplet discharge unit, and the droplet generation module occupies The ground area is less than 1mm*50μm. 5. A method for manufacturing a three-dimensional microfluidic chip structure for droplet generation according to any one of claims 1 to 4, characterized in that: comprising the following steps: 1) The first microchannel layer adopts the first substrate, the first vertical microchannel is processed on the lower surface, and the first semi-open planar microchannel is processed on the upper surface, and the first vertical microchannel and the first semi-open Planar microfluidic communication; 2) The second microchannel layer adopts the second substrate to form a second vertical microchannel layer connecting the lower surface and the upper surface; 3) The third micro-channel layer adopts the third substrate, processes a second semi-open planar micro-channel on the lower surface, processes a third semi-open planar micro-channel on the upper surface, and processes a second semi-open planar micro-channel on the second semi-open planar micro-channel. The flow channel is processed downward to form a third vertical micro-channel; 4) The fourth microchannel layer adopts the fourth substrate, and the fourth vertical microchannel is processed on the lower surface after the fifth vertical microchannel is processed on the upper surface; 5) The fifth microchannel layer adopts the fifth substrate, the fourth semi-open planar microchannel is processed on the lower surface, the sixth vertical microchannel is processed on the upper surface, and the fourth semi-open planar microchannel and the sixth Vertical microchannel communication; 6) The second substrate and the fourth substrate are respectively bonded on both sides of the third substrate to connect the second vertical microchannel layer, the second semi-open planar microchannel, the third vertical microchannel, the third half Open planar micro-channels, fourth vertical micro-channels and fifth vertical micro-channels; 7) The first substrate is bonded to the lower surface of the second substrate, and the fifth substrate is bonded to the upper surface of the fourth substrate, realizing the communication from the first vertical microchannel to the sixth vertical microchannel. 6. The manufacturing method according to claim 5, characterized in that: the materials of the first substrate, the second substrate, the third substrate, the fourth substrate and the fifth substrate include polydimethylsiloxane, acrylic, Silicon, glass or Teflon; in the step 1) to step 5), the processing includes polymer replication molding technology, deep reactive ion etching technology, laser-induced etching rapid prototyping technology, wet etching, hot pressing Printing technology, laser ablation, sandblasting, ultrasonic micromachining or CNC machinery. 7. The manufacturing method according to claim 5, characterized in that: in the step 6) and step 7), the bonding includes thermal bonding, glue bonding, metal interlayer bonding or low temperature bonding.

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