Micro-fluidic chip and micro-fluidic device
By setting up a multi-stage mixing unit and a spiral flow channel in the microfluidic chip, combined with the principles of physical and mechanical, the problem of poor size uniformity and dispersion of droplets in the preparation of giant multi-chamber vesicle droplets is solved, and the more High droplet pass rate and production efficiency.
Patent Information
- Application Number
- CN202421107041.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-20
- Publication Date
- 2025-02-18
- Estimated Expiration
- 2034-05-20
AI Technical Summary
When traditional microfluidic chips prepare giant multi-chamber vesicles, the droplets have poor size uniformity and dispersion, resulting in low product pass rate.
A microfluidic chip is designed, including a first mixing part, a second mixing part and a third mixing part. By providing the droplet structure of the second mixing part and the third mixing part, combining radial centrifugal force, inertia force and dean rotation force, the droplets are formed stably, and the optimal diffusion and mass transfer of the fluid is achieved through the multi-channel structure.
The size uniformity and dispersion of the liquid droplets are improved, thereby improving the pass rate and production efficiency of the liquid droplets.
Smart Images
Figure CN222490106U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a microfluidic chip and a microfluidic device. Background Art
[0002] At present, giant unilamellar vesicles (GUVs) with a radius of more than 1 μm may offer great potential for drug delivery applications. Due to their large internal volume, GUVs can carry a large amount of active compounds as well as micron-sized particles. Traditional methods for preparing GUVs include double emulsion method, octanol-assisted liposome assembly, etc., but these methods have many limitations: (1) low yield of giant vesicles; (2) uneven size of microcapsules; (3) inability to prepare multicompartmental vesicles with multiple chambers. Therefore, microfluidics (MF) has been developed for high-throughput production of monodisperse multicompartmental GUVs and vesicles.
[0003] Microfluidics refers to the technology of manipulating trace amounts of fluids in channels of micrometer size. Microfluidics can precisely control the degree of mixing of fluid molecules by changing factors such as chip shape, fluid flow rate, flow rate, mixing order, etc. Microfluidics preparation is simple, fast, conditionally controllable, and highly repeatable. Current microfluidic chips are mainly used for the preparation of relatively simple two-phase fluids, such as nanoparticles. For more complex substances, such as giant multichamber vesicles (GUVs), which involve the mixing of more than two phases of fluid, the prepared droplets cannot meet the requirements of uniform size and uniform dispersion due to the lack of multi-stage mixing units, resulting in a low product qualification rate. Utility Model Content
[0004] The purpose of the utility model is to overcome the problem of poor uniformity and dispersion of droplet size prepared by traditional microfluidic chips, and to provide a microfluidic chip and a microfluidic device. The microfluidic chip of the utility model improves the uniformity and dispersion of droplet size by setting droplets in the second mixing part and the third mixing part, thereby improving the droplet qualification rate and production efficiency.
[0005] The utility model provides a microfluidic chip, which comprises a chip body, wherein a flow channel is arranged on the chip body, and the flow channel comprises a first mixing part, a second mixing part and a third mixing part;
[0006] The first mixing section comprises a first feeding section, a first confluence section and a first mixing section which are connected in sequence, there are at least two first feeding sections, the first confluence section is connected to the ends of the two first feeding sections, and the first mixing section is an S-shaped structure;
[0007] The second mixing section comprises a second feed section, a second converging section, a branch flow section, a third converging section and a second mixing section, wherein the second converging section, the branch flow section, the third converging section and the second mixing section are sequentially connected in series; there are at least two branch flow sections, and all the branch flow sections are sequentially connected in parallel between the second converging section and the third converging section; the second mixing section is an S-shaped structure; the second feed section is connected to the third converging section;
[0008] The third mixing portion is a spiral flow channel, and the third mixing portion is connected to the end of the second mixing section.
[0009] In the utility model, the fluid forms droplets (such as oil-in-water droplets) after passing through the first mixing section and the second mixing section. The droplets enter the spiral flow channel of the third mixing section. Since the droplets have radial centrifugal force in the spiral microchannel, the radial centrifugal force is combined with the inertia force and Dean rotation force of the fluid to stabilize the droplets.
[0010] In the utility model, the connection between the branch flow segment and the third confluence segment is a multi-channel structure (e.g., a three-channel structure). By diverting the flow, the fluids on both sides and the middle fluid can be merged into the same channel to form a focused flow, thereby achieving optimal diffusion and mass transfer of the fluid. For example, when preparing multi-chamber vesicles, oil-in-water droplets are formed at the third confluence segment. Among them, the shape of the branch flow segment can be conventional in the art, such as a broken line shape. Preferably, there are two branch flow segments, and the two branch flow segments form a hexagonal structure. The angle between adjacent sides of the hexagonal structure is preferably 120°.
[0011] In the present invention, the first mixing section includes a straight section and a bent section, two adjacent straight sections are connected by the bent section, and the straight sections are provided with staggered herringbone grooves. The staggered herringbone grooves can increase the mixing effect without generating a large pressure drop.
[0012] In the utility model, the second mixing section comprises a straight section and a bending section, two adjacent straight sections are connected by the bending section, and the straight sections are provided with the aforementioned staggered herringbone grooves.
[0013] Wherein, the bending section is preferably U-shaped.
[0014] The staggered herringbone grooves preferably include multiple groups of herringbone grooves arranged in sequence along the flow channel direction, and each adjacent two groups of herringbone grooves are staggered around the center line of the flow channel; each group of herringbone grooves includes multiple herringbone grooves arranged in sequence along the flow channel. That is, two groups of herringbone grooves form a cycle, and the misalignment of the herringbone direction between half cycles changes the position of the fluid rotation center and the upper and lower positions of the local cross flow in the cross flow, so that the fluid swings left and right, thereby improving mass transfer and diffusion.
[0015] Each group of the herringbone grooves preferably includes 5 to 6 herringbone grooves. The first mixing section and the second mixing section are preferably each provided with 20 to 30 groups of the herringbone grooves, for example 26 groups.
[0016] The depth of the herringbone grooves is 30-50 μm, for example, 31 μm, and the spacing between adjacent herringbone grooves is 40-60 μm, for example, 50 μm.
[0017] In the utility model, the two first feed sections and the first confluence section form a Y-shaped structure.
[0018] In the present invention, the second feed section is arranged in the area between the second converging section and the third converging section to save space, for example, it is arranged at the center of the hexagonal focusing flow section.
[0019] In the present invention, multiple second mixing parts can be provided according to the number of fluids, and multiple first mixing parts can be connected in sequence. For example, when the number of fluids is three-phase flow, there is one second mixing part, when the number of fluids is four-phase flow, there are two second mixing parts, and so on.
[0020] In the utility model, the third mixing section preferably includes a first single spiral flow channel and a second single spiral flow channel, the starting end of the first single spiral flow channel is connected to the end of the second mixing section, and the end of the first single spiral flow channel is connected to the starting end of the second single spiral flow channel; the first single spiral flow channel and the second single spiral flow channel are parallel to each other and have the same center.
[0021] In the present invention, the width of the flow channel is preferably 100-200 μm, such as 200 μm. The depth of the flow channel is preferably 50-100 μm, such as 79 μm.
[0022] In the utility model, the flow channel further comprises a liquid outlet portion for outputting the mixed fluid, and the liquid outlet portion is connected to the end of the third mixing portion.
[0023] In the utility model, the material of the microfluidic chip is PDMS.
[0024] The utility model also discloses a microfluidic device, which comprises an injection pump system, a pipeline and the aforementioned microfluidic chip.
[0025] In the present invention, the pipeline is preferably a silicone pipeline, and the inner diameter of the pipeline is less than 0.2 mm.
[0026] The positive and progressive effects of the utility model are:
[0027] By adopting the microfluidic chip of the utility model, the two-phase flow is mixed through the first mixing section, and then focused and mixed with other fluids in the second mixing section to form droplets (such as oil-in-water droplets). The droplets are stabilized by the third mixing section to finally form droplets with uniform size and good dispersion, thereby improving the droplet qualification rate and production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0028] Figure 1 It is a schematic diagram of the flow channel structure of the microfluidic chip recorded in Example 1.
[0029] Figure 2 yes Figure 1 A partial enlarged view of middle A.
[0030] Figure 3 This is the particle size distribution diagram of the multilamellar vesicles of Example 3.
[0031] Description of reference numerals:
[0032] First mixing section 1
[0033] The first feeding section 11
[0034] First confluence section 12
[0035] First mixing section 13
[0036] Straight line segment 131
[0037] Bending section 132
[0038] Herringbone groove 133
[0039] Herringbone groove group A
[0040] Herringbone groove period P
[0041] Second mixing section 2
[0042] The second feeding section 21
[0043] Second confluence section 22
[0044] Branch flow section 23
[0045] The third confluence section 24
[0046] Second mixing section 25
[0047] Third mixing section 3
[0048] The first single spiral flow channel 31
[0049] The second single spiral flow channel 32
[0050] Liquid outlet part 4 DETAILED DESCRIPTION
[0051] The present invention is further described below by way of embodiments, but the present invention is not limited to the scope of the embodiments.
[0052] It should be noted that the terms "end" and "starting end" are defined along the direction of fluid flow, and "first", "second" and "third" are only used for descriptive purposes and cannot be understood as indicating or suggesting relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. "Multiple" generally refers to more than one. "Connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection or an integral connection, or it can be indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the utility model can be understood according to specific circumstances.
[0053] The experimental methods in the following examples without specifying specific conditions were carried out according to conventional methods and conditions, or selected according to the product instructions.
[0054] Example 1
[0055] This embodiment discloses a microfluidic chip, such as Figure 1 As shown, it includes a chip body, on which a flow channel is arranged, and the flow channel includes a first mixing part 1, a second mixing part 2 and a third mixing part 3;
[0056] The first mixing section 1 comprises a first feed section 11, a first confluence section 12 and a first mixing section 13 which are connected in sequence. There are two first feed sections 11. The first confluence section 12 is connected to the ends of the two first feed sections 11. The two first feed sections and the first confluence section form a Y-shaped structure.
[0057] The first mixing section 13 is an S-shaped structure. Specifically, the first mixing section 13 includes a straight section 131 and a bent section 132. Two adjacent straight sections 131 are connected by a bent section 132. The bent section 132 is U-shaped. The straight section 131 is provided with staggered herringbone grooves. There are 26 groups of herringbone groove groups A in the first mixing section 13. Each group of herringbone groove groups A includes 5 herringbone grooves 133 arranged in sequence along the flow channel. Two adjacent groups of herringbone groove groups A are staggered around the center line of the flow channel. Two groups of herringbone groove groups A form a herringbone groove period P. Figure 2 The depth of the herringbone grooves 133 is 31 μm, and the interval d1 between adjacent herringbone grooves 133 is 50 μm.
[0058] The second mixing section 2 includes a second feed section 21, a second confluence section 22, a branch flow section 23, a third confluence section 24 and a second mixing section 25. The second confluence section 22, the branch flow section 23, the third confluence section 24 and the second mixing section 25 are connected in series in sequence, wherein there are two branch flow sections 23, and the two branch flow sections 23 are arranged in parallel between the second confluence section 22 and the third confluence section 24, so that the branch flow sections 23 form a hexagonal structure as a whole, and the angle between adjacent sides of the hexagonal structure is 120°.
[0059] The starting end of the second confluence section 22 is connected to the end of the first mixing section 13, the end of the third confluence section 24 is connected to the starting end of the second mixing section 25, the second feed section 21 is connected to the starting end of the third confluence section 24, and the second feed section 21 is arranged at the center position of the branch flow section 23 of the hexagonal structure; the second mixing section 25 is an S-shaped structure, and the structure of the second mixing section 25 is the same as that of the first mixing section 13.
[0060] The third mixing section 3 is a spiral structure, and the third mixing section 3 includes a first single spiral flow channel 31 and a second single spiral flow channel 32. The starting end of the first single spiral flow channel 31 is connected to the end of the second mixing section 25, and the end of the first single spiral flow channel 31 is connected to the starting end of the second single spiral flow channel 32; the first single spiral flow channel 31 and the second single spiral flow channel 32 are parallel to each other and have the same center of circle.
[0061] The flow channel further includes a liquid outlet 4 for outputting the mixed fluid. The liquid outlet 4 is connected to the end of the second single spiral flow channel 32 .
[0062] The width of the flow channel in this embodiment is 200 μm, the depth is 79 μm, and the material of the microfluidic chip is PDMS.
[0063] Example 2
[0064] This embodiment discloses a microfluidic device, which includes a syringe pump system, a pipeline and the microfluidic chip described in Example 1. The pipeline is a silicone pipeline, and the inner diameter of the pipeline is less than 0.2 mm.
[0065] Example 3
[0066] This embodiment discloses a method for preparing a multi-chamber vesicle, which uses the microfluidic chip described in Example 1.
[0067] The sources of the main reagents used in this example are shown in Table 1.
[0068] Table 1
[0069] Reagents Manufacturer or model HFE7500 oil containing PFPE-PEG-PFPE Suzhou SMIC Qiheng Scientific Instrument Co., Ltd. PFPE-COOH Suzhou Cangmu New Materials Co., Ltd. 51798-33-5
[0070] The multicompartmental vesicle prepared in this embodiment is an anionic liposome, the lipid phase of which is composed of DOPC, DOPS and cholesterol; the chamber of the anionic liposome contains a plurality of cationic liposomes and a Tris buffer containing magnesium chloride, and the lipid phase of the cationic liposome is composed of DOPE, DOTAP and cholesterol.
[0071] The specific steps include:
[0072] DOPC, DOPS and cholesterol dissolved in chloroform were mixed in a glass bottle at a molar ratio of 6:3:1, and DOPE, DOTAP and cholesterol dissolved in chloroform were mixed in a glass bottle at a molar ratio of 4:4:2, and dried to form lipid films under a gentle nitrogen flow. The dried DOPC / DOPS / cholesterol lipid films and DOPE / DOTAP / cholesterol lipid films were hydrated in Tris buffer containing 10mM magnesium chloride, and the DOPC / DOPS / cholesterol lipid films were hydrated to a lipid concentration of 5mM in the final buffer, and the DOPE / DOTAP / cholesterol lipid films were hydrated to a lipid concentration of 1.5mM in the final buffer. The two lipid solutions obtained were extruded through a polycarbonate filter with a pore size of 50nm for 9 times, respectively, to obtain a Tris buffer containing magnesium chloride containing an anionic liposome intermediate and a Tris buffer containing magnesium chloride containing cationic liposomes, i.e., a first aqueous phase and a second aqueous phase.
[0073] (2) adding PFPE-COOH to HFE7500 containing 2% PFPE-PEG-PFPE until the concentration of PFPE-COOH in HFE7500 is 10 mM to form an oil phase;
[0074] (3) using a disposable syringe to absorb the first aqueous phase, the second aqueous phase and the oil phase respectively, the volume ratio of the first aqueous phase: the oil phase: the second aqueous phase is 1:5:1, the syringes sucking the first aqueous phase and the second aqueous phase are respectively installed at the entrances of the two first feeding sections 11 on the microfluidic chip, and the syringe sucking the oil phase is installed at the entrance of the second feeding section 21;
[0075] After entering the seventh herringbone groove period P, the first aqueous phase and the second aqueous phase are completely mixed.
[0076] (4) The flow rates were set to 240 μL / h for the first aqueous phase and the second aqueous phase and 1200 μL / h for the oil phase, and the preparation of multilamellar vesicles was started;
[0077] (5) Droplets are formed at the third confluence section 24 in the focusing flow section 22 of the microfluidic chip, and flow out from the liquid outlet 4 of the microfluidic chip and are collected in an EP tube. After collection, the droplets are equilibrated at 4°C for 2 hours and then released;
[0078] (6) Remove excess oil phase from the EP tube. The droplet layer was mixed with a volume ratio of 1:1:1 of droplet: 30 mM Tris buffer: HFE7500 containing 20% 1H,1H,2H,2H-perfluoro-1-octanol. After 30 minutes of equilibrium release, the supernatant was transferred to a 2 mL EP tube and centrifuged at 10,000 r / min for 15 minutes. The supernatant was discarded and 200 μL PBS was added to resuspend the final multicompartmental vesicles.
[0079] The multicompartmental vesicles prepared in Example 3 were observed under a microscope. Figure 3 The results show that the multi-chamber vesicles prepared in Example 3 not only have a smaller particle size but also have a uniform morphology.
Claims
1. A microfluidic chip, characterized in that: It comprises a chip body, on which a flow channel is arranged, and the flow channel comprises a first mixing part, a second mixing part and a third mixing part; The first mixing section comprises a first feeding section, a first confluence section and a first mixing section which are connected in sequence, there are at least two first feeding sections, the first confluence section is connected to the ends of all the first feeding sections, and the first mixing section is an S-shaped structure; The second mixing section comprises a second feed section, a second converging section, a branch flow section, a third converging section and a second mixing section, wherein the second converging section, the branch flow section, the third converging section and the second mixing section are sequentially connected in series; there are at least two branch flow sections, and all the branch flow sections are sequentially connected in parallel between the second converging section and the third converging section; the second mixing section is an S-shaped structure; the second feed section is connected to the third converging section; The third mixing portion is a spiral flow channel, and the third mixing portion is connected to the end of the second mixing section.
2. The microfluidic chip according to claim 1, characterized in that: The first mixing section comprises a straight section and a bending section, two adjacent straight sections are connected by the bending section, and the straight sections are provided with staggered herringbone grooves; And / or, the second mixing section includes a straight section and a bent section, two adjacent straight sections are connected by the bent section, and the straight sections are provided with staggered herringbone grooves.
3. The microfluidic chip according to claim 2, characterized in that: The bending section is U-shaped; And / or, the staggered herringbone grooves include multiple groups of herringbone groove groups arranged in sequence along the flow channel direction, and each two adjacent groups of herringbone groove groups are staggered around the center line of the flow channel; each group of the herringbone groove groups includes multiple herringbone grooves arranged in sequence along the flow channel.
4. The microfluidic chip according to claim 3, characterized in that: Each group of the herringbone grooves includes 5 to 6 herringbone grooves; And / or, the first mixing section and the second mixing section are both provided with 20 to 30 groups of the herringbone groove groups.
5. The microfluidic chip according to claim 3 or 4, characterized in that: The groove depth of the herringbone groove is 30 to 50 μm; And / or, the spacing between adjacent herringbone grooves is 40-60 μm.
6. The microfluidic chip according to claim 1, characterized in that: There are two branch flow sections, and the two branch flow sections form a hexagonal structure; and / or, the two first feed sections and the first confluence section form a Y-shaped structure; And / or, the second feed section is arranged in a region between the second converging section and the third converging section; And / or, one or more second mixing parts are provided. When there are more than one second mixing parts, a plurality of first mixing parts are connected in sequence.
7. The microfluidic chip according to claim 1, characterized in that: The third mixing section includes a first single spiral flow channel and a second single spiral flow channel, the starting end of the first single spiral flow channel is connected to the end of the second mixing section, and the end of the first single spiral flow channel is connected to the starting end of the second single spiral flow channel; the first single spiral flow channel and the second single spiral flow channel are parallel to each other and have the same center.
8. The microfluidic chip according to claim 1, characterized in that: The width of the flow channel is 100 to 200 μm; And / or, the depth of the flow channel is 50-100 μm.
9. The microfluidic chip according to claim 1, characterized in that: The flow channel further comprises a liquid outlet portion for outputting the mixed fluid, and the liquid outlet portion is connected to the end of the third mixing portion.
10. A microfluidic device, characterized in that: The microfluidic chip comprises an injection pump system, a pipeline and the microfluidic chip according to any one of claims 1 to 9.