High-universality and modular-design centrifugal microfluidic reagent storage and release structure

Abstract

The invention discloses a centrifugal microfluidic reagent storage and release structure with high universality and modular design, and relates to the technical field of centrifugal microfluidic chips. Comprising a plurality of puncture structures, an upper sealing layer, a positioning layer, a reagent storage layer and a lower sealing layer, the reagent storage layer is provided with a plurality of liquid storage cavities, and reagents are stored in the liquid storage cavities; one liquid storage cavity corresponds to one puncture structure, the bottom end of the puncture structure is in contact with the lower sealing layer, the top end of the puncture structure upwards penetrates through the liquid storage cavity and then extends out of the positioning layer, the positioning layer is provided with a guide structure, the puncture structure is in sliding connection with the guide structure, the lower sealing layer seals the bottom of the liquid storage cavity, and the lower sealing layer is bonded to the centrifugal micro-fluidic chip. The upper sealing layer has ductility and seals the puncture structure inside. The reagent storage and release device is designed based on a modularization concept, is high in internal integration level, is suitable for storage and release of reagents of various sizes and batches, and can be compatible with storage and release of large-size reagents and small-size reagents at the same time.

Description

Technical Field

[0001] This invention belongs to the field of centrifugal microfluidic chip technology, and more specifically, relates to a highly versatile, modularly designed centrifugal microfluidic reagent storage and release structure. Background Technology

[0002] Centrifugal microfluidic chips with integrated full reaction flow functionality require a structure that can actively control the release of various reagents while simultaneously storing necessary reagents. The reagent storage and release structure for centrifugal microfluidic chips is an active fluid control mechanism that, through the application of external force, allows a specified liquid to enter the microfluidic chip to initiate a series of reactions.

[0003] This structure can be integrated onto a centrifugal microfluidic chip. It stores a series of reagents necessary for the detection reaction. The structure itself is hermetically sealed and can be manufactured and stored independently of the centrifugal microfluidic chip. In use, the structure is sealed and bonded to a designated area of ​​the centrifugal microfluidic chip, and with the aid of external force, the stored reagents can be released.

[0004] Based on the aforementioned working mechanism and characteristics of this structure, it can accommodate reagents and be integrated into centrifugal microfluidic chips, enabling the injection of various reagents into the chip without a liquid injection system. Its ability to be produced and stored independently of the centrifugal microfluidic chip allows for low-cost, high-volume production and independent storage with pre-loaded reagents. Applying this structure to centrifugal microfluidic chips allows the detection platform to achieve automated reagent injection while eliminating the previously complex and redundant reagent dispensing system. This improves the automation and integration of the detection platform, simplifies its system complexity, and reduces the design, development, and manufacturing difficulties. Furthermore, since there are no reagent handling and injection steps, there is no risk of leakage during reagent transfer, resulting in a more stable and pure reaction environment for the detection platform and microfluidic chip.

[0005] In current fully integrated microfluidic chips, reagent storage and release structures that achieve functionality through compression can be categorized into external puncture type and internal puncture type based on their working principle.

[0006] Externally punctured reagent storage and release modules require a matching microfluidic chip with a puncture structure, typically a conical puncture. The reagent storage and release structure is merely a container for storing reagents; when needed, the structure is compressed, causing the conical puncture to break through the sealing layer, allowing the reagent to flow into the corresponding area of ​​the chip. At the reagent level, this method is only suitable for storing and releasing larger volumes of reagents, resulting in a significant dead volume. At the chip design and implementation level, an additional puncture structure needs to be designed, encroaching on the microfluidic chip's design space, increasing design complexity, and placing higher demands on the chip's sealing and fabrication processes, leading to high implementation costs.

[0007] An internal puncture-type reagent storage and release module integrates the puncture structure within the module. Reagent release is achieved simply by pressing the corresponding area of ​​the module. This method offers higher integration and easier chip integration, benefiting chip design. Traditional internal puncture designs rely on the large volume of reagent generating significant centrifugal pressure at the puncture site during centrifugation to overcome the interfacial tension and allow the reagent to enter the chip. Furthermore, because traditional internal puncture designs have only one puncture site, the reagent must overcome both the interfacial tension of the puncture site and the internal gas pressure of the chip during centrifugation, requiring higher rotation speeds. This hinders subsequent fluid control within the chip. Current solutions to this problem involve increasing the size of the puncture site and the reagent volume. However, this results in more reagent residue at the puncture site, creating a larger dead volume and increasing reaction costs. Increasing the puncture site size also renders the reagent release and storage structure unsuitable for releasing small volumes of reagent, as a significant portion, or even all, of the reagent will remain in the puncture site, resulting in poor versatility of the reagent release and storage structure. The increased puncture hole size and reagent volume also result in a larger structural volume, which reduces the vertical projection area of ​​the centrifugal microfluidic chip, increasing the difficulty of chip design and fabrication. Existing solutions rely on internal pressure changes and the gravity of the reagent itself to inject it into the chip after the puncture step, thus limiting their application to large-volume reagents. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to provide a highly versatile and modular centrifugal microfluidic reagent storage and release structure. Based on the modular design concept, it has a high degree of internal integration and is suitable for the storage and release of reagents of various volumes and batches. It can simultaneously accommodate the storage and release of large-volume reagents (500ul) and small-volume reagents (50ul).

[0009] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a highly versatile and modular centrifugal microfluidic reagent storage and release structure, comprising several puncture structures and an upper sealing layer, a positioning layer, a reagent storage layer, and a lower sealing layer stacked and bonded from top to bottom; the reagent storage layer has several liquid storage chambers in which the reagent is stored; one liquid storage chamber corresponds to one puncture structure, the bottom end of the puncture structure contacts the lower sealing layer, and the top end extends upward through the liquid storage chamber to extend out to the positioning layer, the positioning layer has a guide structure, the puncture structure is slidably connected to the guide structure, the lower sealing layer seals the bottom of the liquid storage chamber, the lower sealing layer is bonded to the centrifugal microfluidic chip, and the upper sealing layer is extensible, sealing the puncture structure inside.

[0010] Preferably, the puncture structure includes at least two puncture columns, with puncture tips at the bottom of each column.

[0011] Preferably, the puncture column is provided with a flow guide groove.

[0012] Preferably, the upper part of the puncture mechanism is columnar, the guide structure is a guide hole, and the puncture mechanism slides within the guide hole.

[0013] Preferably, the reagent storage and release structure further includes an adhesive layer that bonds the positioning layer to the reagent storage layer.

[0014] Preferably, the reagent storage layer is provided with a liquid inlet chamber, the top of which is sealed by an upper sealing layer, and the bottom is connected to the chip reagent chamber of the centrifugal microfluidic chip.

[0015] Preferably, the upper sealing layer is provided with a sample dispensing hole, which is connected to the liquid inlet chamber. The sample dispensing hole is covered with a sample dispensing hole sealing layer, which is provided with a smooth release paper layer. The sample enters the liquid inlet chamber through the sample dispensing hole and then enters the chip reagent chamber. The smooth release paper layer is then torn off, and the sample dispensing hole is sealed by the sample dispensing hole sealing layer.

[0016] The beneficial effects of adopting the above technical solution are as follows:

[0017] 1. The puncture structure of the present invention is provided with at least two puncture columns, so that the lower sealing layer forms at least two puncture holes, thereby making it easier to balance the air pressure during the reagent transfer process and reducing the difficulty of reagent flowing into the chip; the puncture columns are provided with drainage grooves, so that the reagent can flow directly into the chip reagent cavity along the puncture structure, reducing the dead volume during the reagent release process.

[0018] 2. The internal puncture-type reagent storage and release structure proposed in this solution can not only release large volumes of reagents, but also accommodate the release of small volumes of reagents. Furthermore, it can further reduce the size of the puncture structure and decrease the dead volume of reagents to accommodate the release of extremely small amounts of reagents.

[0019] 3. This solution features a compact structure and high functional integration, offering greater versatility compared to existing solutions. It addresses the challenges of reagent release and the significant dead volume ratio associated with releasing small-volume reagents. Its compact design also benefits chip design and fabrication. Attached Figure Description

[0020] Figure 1 This is an exploded view of the overall structure of the present invention;

[0021] Figure 2 This is a schematic diagram of the reagent storage layer structure;

[0022] Figure 3 This is a top view of the reagent storage layer;

[0023] Figure 4 This is a schematic diagram of the puncture structure;

[0024] Figure 5 This is a diagram showing the location of the puncture site;

[0025] Figure 6 This is a schematic diagram showing the state of the reagent in the reservoir during rotation;

[0026] Figure 7 yes Figure 6 AA section view in the middle;

[0027] Figure 8 This is a schematic diagram of the sample well sealing process;

[0028] In the diagram: 1. Upper sealing layer, 2. Puncture structure, 21. Guide groove, 22. Puncture tip, 23. Puncture column, 3. Positioning layer, 4. Adhesive layer, 5. Reagent storage layer, 51. Storage layer body, 52. Liquid storage chamber, 53. Liquid inlet chamber, 54. Positioning hole, 6. Lower sealing layer, 7. Puncture hole, 8. Reagent, 9. Centrifugal microfluidic chip, 10. Chip reagent chamber, 11. Sample dispensing hole sealing layer, 111. Glossy release paper layer, 12. Sample dispensing hole. Detailed Implementation

[0029] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0030] like Figure 1As shown, the reagent storage and release structure includes a puncture structure 2 and, from top to bottom, an upper sealing layer 1, a positioning layer 3, an adhesive layer 4, a reagent storage layer 5, and a lower sealing layer 6, stacked and bonded together. The upper sealing layer 1 and the lower sealing layer 6 seal the upper and lower surfaces of the entire structure, making the reagent storage layer 5 a sealed cavity. The reagent storage and release structure is coaxially mounted on a centrifugal microfluidic chip 9.

[0031] The upper sealing layer 1 is made of a high-ductility cold-rolled aluminum sheet, cut to a vertical projection outline and then pressed using a corresponding mold. The sheet also needs to be coated with adhesive on the bottom to facilitate a sealed connection with the positioning layer 3. The upper sealing layer 1 is made of a high-ductility metal layer because it needs to have a tight seal to ensure that the reagent in the reagent storage layer 5 does not leak out during long-term storage. Simultaneously, this layer needs to have a certain degree of protrusion to accommodate the portion of the puncture structure 2 that protrudes above the positioning layer 3 before puncture.

[0032] like Figure 8 As shown, the upper sealing layer 1 has a sample dispensing hole 12, which is connected to the liquid inlet chamber 53. The liquid inlet chamber 53 is connected to the reaction chamber of the centrifugal microfluidic chip 9. A sample dispensing hole sealing layer 11 is adhered to the upper sealing layer 1, and a glossy release paper layer 111 is provided on the sample dispensing hole sealing layer 11. Generally, the sample dispensing hole sealing layer 11 is a single-sided adhesive aluminum foil sticker, one side of which is completely covered with double-sided adhesive. The glossy release paper layer 111 covers half of the adhesive-covered surface near the center, while the remaining exposed double-sided adhesive area is used for bonding and fixing with the upper sealing layer 1. In the default state, the sample dispensing hole sealing layer 11 retains the glossy release paper layer 111. After sample dispensing, the glossy release paper layer 111 is peeled off, and then the sample dispensing sealing layer 11 is completely placed on the upper sealing layer 1 to completely cover the sample dispensing hole 12, completing the seal. Other single-sided stickers with sealing function can be used as the sealing layer 11 for the sample filling hole. The manufacturing process can be cutting, stamping, laser cutting, etc.

[0033] like Figure 4 As shown, the puncture structure 2 includes two puncture posts 23, each with a puncture tip 22 at its bottom. The puncture post 23 is annular, with a guide groove 21 on its inner wall. When external force presses the upper sealing layer 1 against the puncture structure 2, the puncture post 23 will puncture two holes 7 in the lower sealing layer 6 (e.g., ...). Figure 5-7 As shown, one is located at the proximal end and the other at the distal end, achieving pressure balance between the liquid storage chamber 5 and the chip reagent chamber 10, reducing the difficulty of reagent inflow. After puncture, the puncture column 23 contacts the bottom of the chip reagent chamber 10, and the reagent can flow directly into the chip reagent chamber 10 along the guide groove 21 on the puncture column 23 under the action of surface tension and centrifugal force, reducing interfacial tension resistance.

[0034] The puncture structure 2 needs to be fabricated using rigid, biocompatible materials such as PMMA and PC. Available fabrication methods include 3D printing and injection molding. The minimum applicable reagent volume for this design depends on the minimum usable size of the puncture structure 2 and the size of the puncture orifice it forms. The specific dimensions of the puncture structure 2 need to be determined based on the actual reagent usage, but the design shape of the puncture post 23 at its base remains constant.

[0035] The function of the positioning layer 3 is to position the puncture structure 2, ensuring that its position does not shift during prolonged holding and allowing it to puncture perpendicularly during compression. The thickness of the positioning layer 3 should not be too high, generally kept within 1 mm. The positioning layer 3 is made of PMMA material and processed using laser cutting technology. Alternatively, other stable materials and available processing techniques can also be used.

[0036] The adhesive layer 4 is used to bond and seal the positioning layer 3 and the reagent storage layer 5. Its planar shape is the same as the vertical projection of the reagent storage layer 5, and it is laser-cut using 3M double-sided adhesive. The adhesive layer 4 can also be integrated with the reagent storage layer 5 for simultaneous processing as needed. Furthermore, using a bonding process to bond and seal the positioning layer 3 and the reagent storage layer 5 is also a feasible solution.

[0037] like Figure 2-3 As shown, the reagent storage layer 5 includes a storage layer body 51, a liquid storage chamber 52, and a liquid inlet chamber 53. The lower sealing layer 6 and the upper sealing layer 1 seal the liquid storage chamber 52 to form a closed cavity. The thickness of the reagent storage layer 5 and the area of ​​its internal perforated shape directly determine the volume of reagents it can hold. Generally, a thickness of 5 mm is a suitable parameter, which can be appropriately modified according to actual needs.

[0038] The lower sealing layer 6 is cut from rigid aluminum foil, with a foil thickness of no less than 0.07 mm, which allows for relatively low puncture force while ensuring sealing stability. The lower sealing layer 6 requires double-sided adhesive coating. The top coating is used for sealing and bonding with the reagent storage layer 5, while the bottom coating needs to be covered with release paper, which is peeled off when it needs to be combined with the centrifugal microfluidic chip 9.

[0039] By default, the inlet chamber 53 is empty. At the start of the reaction, the sample to be tested is injected through the sample dispensing port 12. The lower opening of the inlet chamber 53 connects it to the reaction chamber of the centrifugal microfluidic chip 9. After the sample is injected into the inlet chamber 53, it connects directly to the centrifugal microfluidic chip 9 without the need for puncture. The sample enters the corresponding reaction chamber of the centrifugal microfluidic chip 9. After the sample injection is complete, the inlet chamber 53 is isolated from the outside environment through the sample dispensing port sealing layer 11. At this point, the reagent storage and release structure and the centrifugal microfluidic chip 9 are completely isolated from the outside environment, and the reaction process begins.

[0040] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A highly versatile, modularly designed centrifugal microfluidic reagent storage and release structure, characterized in that, It includes several puncture structures (2) and an upper sealing layer (1), a positioning layer (3), a reagent storage layer (5), and a lower sealing layer (6) stacked and bonded from top to bottom; the reagent storage layer (5) is provided with several liquid storage chambers (52), and the reagent is stored in the liquid storage chambers (52); one liquid storage chamber (52) corresponds to one puncture structure (2), the bottom end of the puncture structure (2) contacts the lower sealing layer (6), and the top end extends upward through the liquid storage chamber (52) and extends out to the positioning layer (3). The positioning layer (3) is provided with a guide structure, and the puncture structure (2) is slidably connected to the guide structure. The lower sealing layer (6) seals the bottom of the liquid storage chamber (52) and is bonded to the centrifugal microfluidic chip (9). The upper sealing layer (1) is extensible and seals the puncture structure (2) inside.

2. The highly versatile, modularly designed centrifugal microfluidic reagent storage and release structure according to claim 1, characterized in that, Each puncture structure (2) includes at least two puncture columns (23), with a puncture tip (22) at the bottom end of each puncture column (23).

3. The highly versatile, modularly designed centrifugal microfluidic reagent storage and release structure according to claim 2, characterized in that, The puncture column (23) is provided with a guide groove (21).

4. The highly versatile, modularly designed centrifugal microfluidic reagent storage and release structure according to claim 1, characterized in that, The upper part of the puncture mechanism (2) is columnar, and the guide structure is a guide hole. The puncture mechanism (2) slides within the guide hole.

5. The highly versatile, modularly designed centrifugal microfluidic reagent storage and release structure according to claim 1, characterized in that, The reagent storage and release structure also includes an adhesive layer (4) that bonds the positioning layer (3) to the reagent storage layer (5).

6. The highly versatile, modularly designed centrifugal microfluidic reagent storage and release structure according to claim 1, characterized in that, The reagent storage layer (5) is provided with a liquid inlet chamber (53). The top of the liquid inlet chamber (53) is sealed by the upper sealing layer (1), and the bottom is connected to the chip reagent chamber (10) of the centrifugal microfluidic chip (9).

7. The highly versatile, modularly designed centrifugal microfluidic reagent storage and release structure according to claim 6, characterized in that, The upper sealing layer (1) is provided with a sample feeding hole, which is connected to the liquid inlet chamber (53). The sample feeding hole is covered with a sample feeding hole sealing layer (11). The sample feeding hole sealing layer (11) is provided with a smooth release paper layer (111). The sample enters the liquid inlet chamber (53) through the sample feeding hole (12) and then enters the chip reagent chamber (10). The smooth release paper layer (111) is then peeled off, and the sample feeding hole (12) is sealed by the sample feeding hole sealing layer (11).

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