Micro-fluidic chip and micro-fluidic chip manufacturing method

Abstract

The invention discloses a micro-fluidic chip and a manufacturing method of the micro-fluidic chip. According to the micro-fluidic chip, the photoconductive area is formed between the at least two first supporting pieces, the photoconductive layer is arranged in the photoconductive area, light beams irradiate the lower polar plate, dielectrophoretic force is generated through the photoconductive layer to drive cells to move, and the cells can be effectively controlled; the supporting structure between the upper polar plate and the lower polar plate is divided into the first supporting pieces and the second supporting pieces, the at least two first supporting pieces are adjacently arranged, a microfluid channel is formed between the two adjacent first supporting pieces, and the second supporting pieces are used for forming auxiliary supporting between the upper polar plate and the lower polar plate, so that the stability of the micro-fluidic chip can be effectively improved; besides, the second supporting piece is arranged on the outer side of the first supporting piece, so that the movement of cells in the microfluid channel is not interfered, and a stable and uniform supporting effect can be provided on the outer side.

Description

Technical Field

[0001] The present invention relates to the field of microfluidic technology, and in particular to a microfluidic chip and a method for manufacturing the microfluidic chip. Background Art

[0002] Currently, transistor-based photoelectric tweezers technology has been used to manipulate (e.g., select or move) micro-objects such as cells, bacteria, and microspheres. The typical structure of this type of photoelectric tweezers device is to set a microfluidic channel between two upper and lower electrodes, where the upper electrode is usually a glass plate coated with indium tin oxide (ITO), and the lower electrode is a metal electrode, on which a phototransistor array is arranged to replace the ordinary photoelectric layer. When patterned light is irradiated on a specific area on the phototransistor array, the activated transistor allows current to pass, thereby forming a non-uniform electric field in the microfluidic channel, generating a dielectrophoresis (DEP) force that can manipulate cells.

[0003] In the prior art, a support structure for supporting the gap between the upper electrode plate and the lower electrode plate is provided in the microfluidic channel of the microfluidic chip. However, the conventional support structure has poor stability, and the finished product is often damaged due to short-term use or transportation, and cannot provide a stable support effect. Summary of the invention

[0004] Based on this, it is necessary to provide a microfluidic chip to improve the stability of the structure in response to the existing problems.

[0005] The present application provides a microfluidic chip, comprising:

[0006] A lower electrode plate, wherein a photoconductive layer is provided on the upper surface of the lower electrode plate to form a photoconductive region;

[0007] an upper electrode plate capable of transmitting a light beam and allowing the light beam to illuminate the photoconductive region to generate a dielectrophoretic force; and

[0008] The support structure includes at least two first support members for forming a flow channel, and a second support member located outside the first support members, at least two of the first support members and the second support members are respectively connected to the upper electrode plate and the lower electrode plate, and the two adjacent first support members of the lower electrode plate form the photoconductive area as an enclosed area.

[0009] Preferably, the first support member includes a first side and a second side opposite to each other, the first side is close to the upper electrode plate, the second side is close to the lower electrode plate, and a size of the first support member gradually increases from the first side toward the second side.

[0010] Preferably, the side surface of the first support member is a concave arc surface, and the light beam passing through the upper electrode plate is reflected to the photoconductive area through the concave arc surface.

[0011] Preferably, the concave arc surface of the first support member is a non-uniform curved surface, and the light beam passing through the upper electrode plate is evenly reflected to the photoconductive region through the concave arc surface.

[0012] Preferably, the side surface of the first support member is an inclined surface, and the light beam passing through the upper electrode plate is reflected to the photoconductive region through the inclined surface.

[0013] Preferably, the first support member is doped with a micro-bead structure for improving the stability of the first support member, and the size of the micro-bead structure is 50 μm-200 μm.

[0014] Preferably, the first support member is provided on the upper electrode plate, and the second support member is provided on the lower electrode plate. The upper electrode plate and the lower electrode plate are positioned and bonded using a thermal bonding technology to connect the first support member to the second support member, and the second support member to the first support member.

[0015] Compared with the prior art, the technical solution disclosed in the present invention has the following beneficial effects:

[0016] 1. A photoconductive region is formed between at least two first support members, and a photoconductive layer is provided in the photoconductive region. The light beam irradiates the lower electrode plate and generates a dielectrophoretic force through the photoconductive layer to drive the cell movement, thereby realizing effective manipulation of the cells; 2. The support structure between the upper electrode plate and the lower electrode plate is divided into a first support member and a second support member, and at least two first support members are arranged adjacent to each other, and a microfluidic channel is formed between two adjacent first support members. The second support member is used to form an auxiliary support between the upper electrode plate and the lower electrode plate, thereby effectively improving the stability of the microfluidic chip; 3. The second support member is then arranged on the outside of the first support member, which can not only not interfere with the movement of cells in the microfluidic channel, but also provide a stable and uniform support effect on the outside. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] By referring to the following drawings, the exemplary embodiments of the present invention can be more completely understood. The drawings are used to provide a further understanding of the embodiments of the present application, and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present invention and do not constitute a limitation of the present invention. In the drawings, the same reference numerals generally represent the same parts or steps.

[0018] Figure 1 A schematic diagram of the structure of a fluidic chip microcomputer according to an exemplary embodiment of the present application;

[0019] Figure 2 It is a schematic diagram of the structure of a microfluidic chip in the prior art;

[0020] Figure 3The schematic diagram of the partial structure of the fluidic chip provided by an exemplary embodiment of the present application is shown. Figure 1 ;

[0021] Figure 4 The schematic diagram of the partial structure of the fluidic chip provided by an exemplary embodiment of the present application is shown. Figure 2 .

[0022] Reference numerals

[0023] 10-lower plate;

[0024] 20-upper plate;

[0025] 31 - first support member; 311 - first side; 312 - second side; 32 - second support member. DETAILED DESCRIPTION

[0026] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0027] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0028] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "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; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0030] Example 1

[0031] See also Figure 1 , Figure 3 as well as Figure 4 The embodiment of the present application provides a microfluidic chip, including an upper electrode plate 20, a lower electrode plate 10 and a support structure located between the upper electrode plate 20 and the lower electrode plate 10, wherein a photoconductive layer is provided on the upper surface of the lower electrode plate 10 to form a photoconductive region, and the photoconductive layer may be a single layer, a multilayer or a patterned structure; the upper electrode plate 20 is capable of transmitting a light beam, and after the light beam passes through the upper electrode plate 20, it can irradiate the photoconductive region and generate a dielectrophoretic force; the support structure includes a first support member 31 and a second support member 32, at least two first support members 31 for forming a flow channel, and a second support member 32 located outside the first support member 31, at least two first support members 31 and second support members 32 are respectively connected to the upper electrode plate 20 and the lower electrode plate 10, and the two adjacent first support members 31 of the lower electrode plate 10 form a photoconductive region as an enclosed area.

[0032] Compared with the prior art, the technical solution disclosed in the embodiment of the present application has the following beneficial effects: 1. A photoconductive region is formed between at least two first support members 31, and a photoconductive layer is provided in the photoconductive region. The photoconductive layer can be provided in the photoconductive region by coating, or by physical vapor deposition, chemical vapor deposition, solution method, atomic layer deposition, etc. The specific setting means of the photoconductive layer is not solely limited here. The light beam irradiates the lower electrode plate 10 and generates a dielectric electrophoretic force through the photoconductive layer to drive the cell movement, so as to realize the effective manipulation of the cells, and the specific manipulation includes screening and movement, etc.; 2. The support structure between the upper electrode plate 20 and the lower electrode plate 10 is divided into a first support member 31 and a second support member 32. At least two first support members 31 are arranged adjacent to each other, and a microfluidic channel is formed between the two adjacent first support members 31. The second support member 32 is used to form an auxiliary support between the upper electrode plate 20 and the lower electrode plate 10, which can effectively improve the stability of the microfluidic chip; 3. The second support member 32 is arranged on the outside of the first support member 31, which can not only not interfere with the movement of cells in the microfluidic channel, but also provide a stable and uniform support effect on the outside.

[0033] Specifically, the photoconductive layer can be made of one or more of: hydrogenated amorphous silicon (a-Si:H), titanium phthalocyanine (TiOPC), CulnSe2, cadmium sulfide (CdS), perovskite materials, quantum dot materials, etc. It can be a photoconductive material of a single material or a photoconductive material of a composite material. As long as the dielectrophoretic force can be generated through the photoconductive layer, no sole limitation is made on the specific materials and proportions of the photoconductive layer.

[0034] In addition, the photoconductive layer can form a PNP (phototransistor), NPN (phototransistor) or PIN (photodiode) structure on the substrate of the lower electrode plate 10. The specific structure of the photoconductive layer formed on the substrate of the lower electrode plate 10 is not limited here.

[0035] like Figure 2 As shown, in conventional microfluidic chips, the size of the support structure between the upper plate and the lower plate is generally uniform in size from top to bottom, and the support structure is set to a columnar shape so that the support structure can support the micro-object flow channel between the upper plate and the lower plate. The amount of light entering from the direction of the upper plate will be limited by the shape of the support structure, resulting in a weak dielectrophoretic force generated in the photoconductive area, which makes the driving force for cells or microorganisms insufficient and cannot effectively drive cells or microorganisms to move along a predetermined trajectory. However, if the light intensity is directly increased to irradiate the photoconductive area, the light beam may directly damage the cells or microorganisms, resulting in experimental failure.

[0036] Preferably, in one embodiment, Figure 1 , Figure 3 as well as Figure 4 As shown, the first support member 31 includes a first side 311 and a second side 312 opposite to each other, the first side 311 is close to the upper plate 20, the second side 312 is close to the lower plate 10, and the size of the first support member 31 gradually decreases from the second side 312 toward the first side 311. In this embodiment, the size of the second side 312 of the first support member 31 is consistent with the size of the support structure of the conventional microfluidic chip, and the size of the first support member 31 is set to gradually decrease from the second side 312 close to the lower plate 10 to the first side 311 close to the upper plate 20. In this way, the area enclosed by the first sides 311 of two adjacent first support members 31 is larger than the area of ​​the photoconductive region, and the amount of light beam entering the micro-object flow channel from the side of the upper plate 20 is greater than that of the conventional microfluidic chip, and then the side wall of the first support member 31 refracts the light beam entering the micro-object flow channel to the photoconductive region of the lower plate 10. In this way, the amount of light entering the microfluidic chip is increased, and the dielectrophoretic force generated in a single photoconductive region is enhanced, so that the driving effect on cells or microorganisms can be effectively improved.

[0037] Preferably, in one embodiment, Figure 4 As shown, the side surface of the first support member 31 is a concave arc surface, and the light beam passing through the upper electrode plate 20 is reflected to the photoconductive area by the concave arc surface. After the light beam passes through the upper electrode plate 20, part of the light beam will directly irradiate the photoconductive area; another part of the light beam will irradiate the side surface of the first support member 31, and this part of the light beam will be reflected by the concave arc surface and irradiate the photoconductive area, so that the dielectrophoretic force generated in the photoconductive area is stronger, thereby effectively improving the driving effect on cells or microorganisms.

[0038] Preferably, in one embodiment, Figure 4 As shown, the concave arc surface of the first support member 31 is a non-uniform curved surface, and the light beam passing through the upper electrode plate 20 is evenly reflected to the photoconductive area through the concave arc surface. The curved surface satisfies the following formula:

[0039]

[0040] Among them, c is the curvature (the inverse of the radius of curvature), which determines the curvature of the basic surface; k is the cone constant, which controls the type of surface; α1, α2, α3 are aspheric coefficients, which are used to correct the high-order aberrations of the basic conic surface; by adjusting c, k and αi, the shape of the aspheric surface can be accurately controlled, the aberration caused by the traditional spherical or conic surface can be significantly reduced, and the uniformity of the surface reflection can be improved. The light beam passing through the upper electrode plate 20 is evenly reflected to the photoconductive area, which can make the dielectrophoretic force in a single photoconductive area more balanced.

[0041] Preferably, in one embodiment, the first support member 31 is doped with a microbead structure (not shown) for improving the stability of the first support member 31, and the size of the microbead structure is 50μm-200μm. Since the size of the first support member 31 is adjusted from a columnar shape to a tapered shape from the lower plate 10 to the upper plate 20, the stability of the first support member 31 will be reduced. By doping the microbead structure in the first support member 31, the microbead structure can be made of polystyrene and have a size of 50μm-200μm, which can provide stability for supporting the first support member 31 and prevent the first support member 31 from being easily damaged. In specific application scenarios, microfluidic chips with different microbead sizes can also be selected according to the size of cells or micro-objects. For example, when processing cells with a size of 30μm, a microfluidic chip doped with 50μm microbeads can be used.

[0042] Preferably, in one embodiment, Figure 1 As shown, a first support member 31 is provided on the upper electrode plate 20, and a second support member 32 is provided on the lower electrode plate 10. The upper electrode plate 20 and the lower electrode plate 10 are positioned and bonded using a thermal bonding technology, which is used to connect the first support member 31 to the second support member 32, and connect the second support member 32 to the first support member 31. Since thermal bonding has the advantage of high precision, and the first side 311 of the first support member 31 is small in size, the thermal bonding technology connects the upper electrode plate 20 and the lower electrode plate 10, which can not only ensure the stability of the connection, but also effectively ensure the high precision of the micro-object flow channel.

[0043] Example 2

[0044] Preferably, in this embodiment, except that the structure of the first support member 31 is different from the shape of the first support member 31 in Embodiment 1, other structures are consistent and will not be further described herein. Figure 3As shown, the side surface of the first support member 31 is an inclined surface, and the light beam passing through the upper electrode plate 20 is reflected to the photoconductive area through the inclined surface. The first support member 31 is set to a cone or a polygonal pyramid. In the photoconductive area between two adjacent first support members 31, as long as the first support member 31 can reflect the light and finally reflect it to the corresponding photoconductive area and generate a dielectrophoretic force, it will be fine.

[0045] Example 3

[0046] The present invention also provides a method for manufacturing a microfluidic chip, comprising the following steps:

[0047] S1. Provide a prefabricated lower electrode plate, which may be a structure of an ITO glass layer and a Cr layer stacked in sequence on a substrate, and then deposit a photoconductive layer on the surface of the prefabricated lower electrode plate. The photoconductive layer may be one or more of hydrogenated amorphous silicon (a-Si:H), titanium phthalocyanine (TiOPC), CulnSe2, cadmium sulfide (CdS), perovskite material, quantum dot material, etc., and may be a photoconductive material of a single material or a photoconductive material of a composite material, and coat a first support member on the outer side of the photoconductive layer, and the first support member may be formed once by photoresist, or may be formed multiple times, so that the prefabricated lower electrode plate forms a lower electrode plate;

[0048] S2. Providing a prefabricated upper electrode plate, the prefabricated upper electrode plate may be a structure in which a conductive layer is provided on a substrate, a photoresist is spin-coated on the conductive surface of the prefabricated upper electrode plate, and a microchannel structure is formed after exposure and development through a mask;

[0049] S3. The prefabricated upper electrode plate of step S2 is split to obtain an upper electrode plate having a size corresponding to that of the lower electrode plate;

[0050] S4. Coating the surface of the microchannel structure to form a second support member, and UV curing after coating to form a second support member;

[0051] S5. Align the upper electrode plate and the lower electrode plate by vacuum adsorption, and form a microfluidic chip by thermal bonding technology.

[0052] Preferably, the height of the first support member can be adjusted by multiple coatings and kept corresponding to the height of the second support member. Since the size of the first support member requires the second support member to jointly support the upper electrode plate and the lower electrode plate, and the first support member needs to be adjusted in height according to the curvature requirements of the side, the second support member needs to match the height of the first support member, but the second support member cannot be formed at one time due to process reasons, and can be formed by multiple coatings so that it can assist in supporting the upper electrode plate and the lower electrode plate.

[0053] It can be understood that the same or similar parts of the above embodiments can be referenced to each other, and the contents not described in detail in some embodiments can refer to the same or similar contents in other embodiments.

[0054] It should be noted that, in the description of the present invention, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of the present invention, unless otherwise specified, the meaning of "plurality" refers to at least two.

[0055] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0056] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A microfluidic chip, characterized in that: include: A lower electrode plate, wherein a photoconductive layer is provided on the upper surface of the lower electrode plate to form a photoconductive region; An upper electrode plate capable of transmitting a light beam and allowing the light beam to irradiate the photoconductive region to generate a dielectrophoretic force; as well as The support structure includes at least two first support members for forming a flow channel, and a second support member located outside the first support members, at least two of the first support members and the second support members are respectively connected to the upper electrode plate and the lower electrode plate, and the two adjacent first support members of the lower electrode plate form the photoconductive area as an enclosed area.

2. The microfluidic chip according to claim 1, characterized in that: The first support member includes a first side and a second side opposite to each other, the first side is close to the upper electrode plate, the second side is close to the lower electrode plate, and the cross-sectional width of the first support member gradually decreases from the second side toward the first side.

3. The microfluidic chip according to claim 2, characterized in that: The side surface of the first support member is a concave arc surface, and the light beam passing through the upper electrode plate is reflected to the photoconductive area through the concave arc surface.

4. The microfluidic chip according to claim 3, characterized in that: The concave arc surface of the first support member is a non-uniform curved surface, and the light beam passing through the upper electrode plate is evenly reflected to the photoconductive region through the concave arc surface.

5. The microfluidic chip according to claim 2, characterized in that: The side surface of the first supporting member is an inclined surface, and the light beam passing through the upper electrode plate is reflected to the photoconductive area through the inclined surface.

6. The microfluidic chip according to any one of claims 2 to 5, characterized in that: The first support member is doped with a micro-bead structure for improving the stability of the first support member, and the size of the micro-bead structure is 50 μm-200 μm.

7. The microfluidic chip according to claim 1, characterized in that: The first support member is provided on the upper electrode plate, and the second support member is provided on the lower electrode plate. The upper electrode plate and the lower electrode plate are positioned and bonded using a thermal bonding technology to connect the first support member to the second support member, and the second support member to the first support member.

8. A method for manufacturing a microfluidic chip, characterized in that: The following steps are involved: S1. Providing a prefabricated lower electrode plate, depositing a photoconductive layer on the surface of the prefabricated lower electrode plate, and coating a first support member on the outside of the photoconductive layer to form a lower electrode plate; S2. Providing a prefabricated upper electrode plate, spin-coating a photoresist on the conductive surface of the prefabricated upper electrode plate, and forming a microchannel structure after exposure and development through a mask; S3. The prefabricated upper electrode plate of step S2 is split to obtain an upper electrode plate having a size corresponding to the lower electrode plate; S4. Coating the surface of the microchannel structure to form a second support member, and UV curing after coating to form a second support member; S5. Align the upper electrode plate and the lower electrode plate by vacuum adsorption, and form a microfluidic chip by thermal bonding technology.

9. The method for manufacturing a microfluidic chip according to claim 8, wherein: The height of the first support member is adjusted to be equal to the height of the second support member through multiple coatings.

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