Nanopore micro-nano detection liquid pool device suitable for circuit measurement

Abstract

The utility model discloses a nanopore micro-nano detection liquid pool device suitable for circuit measurement, which is characterized in that a first nanopore liquid pool base and a second nanopore liquid pool base are assembled through a connecting piece, the middle part of the first nanopore liquid pool base is provided with a first middle through hole, the middle part of the second nanopore liquid pool base is provided with a second middle through hole, and the first middle through hole and the second middle through hole are connected through a connecting piece. The chip and the sealing element are arranged between the first middle through hole and the second middle through hole; an inclined first injection hole and an inclined second injection hole which are communicated with the first middle through hole are formed in the first nanopore liquid pool base; an inclined third injection hole and an inclined fourth injection hole which are communicated with the second middle through hole are formed in the second nanopore liquid pool base; the first electrode hole for placing the electrode is communicated with the first injection hole, and the second electrode hole for placing the electrode is communicated with the third injection hole. Pollution and bubbles caused when the electrode is repeatedly inserted into liquid can be reduced, and stability and accuracy of measurement are improved.

Description

Technical Field

[0001] The utility model relates to a micro-nano liquid cell device, in particular to a nano-pore micro-nano detection liquid cell device suitable for circuit measurement. Background Technique

[0002] At present, the application of nano-pore single molecule sensors is expanding day by day. With the advantages of label-free and high sensitivity, they have broad prospects in the fields of genomics, biomedical diagnosis and treatment, and health and safety. The core components for nano-pore single molecule sensors to achieve high-sensitivity detection are nano-pore chips and their assembled liquid cells. Especially, different from the transmembrane self-assembly of protein pores, the key problem of nano-pore sensing is how to efficiently and accurately assemble nano-pore chips in micro-nano detection liquid cells to achieve nano-pore conduction and form a measurable ion channel circuit. Currently, the general size of solid-state nano-pore chips is 2-3mm, which is small in size. The assembled detection liquid cells embedded in them are complex, requiring professionals to operate in the laboratory and consuming time. At the same time, the conduction rate of nano-pore assembly is unstable, and repeated operations are likely to cause membrane damage. The assembled liquid cell mainly serves as a liquid addition and storage container, and external electrodes need to be inserted to connect to the instrument. The electrodes are randomly immersed in the liquid cell channel, which is easy to introduce contamination and generate bubbles at the interface, affecting the detection accuracy. Especially during the measurement process, the electrodes are easily affected externally, resulting in unstable contact with the electrolyte solution, thus leading to inaccurate signals and data in nano-pore measurement and bringing inconvenience to the experiment. Therefore, how to further improve the assembly effect of micro-nano liquid cells, improve the pore and electrode design, and enhance the stability and convenience of the nano-pore measurement system are problems that need to be solved by researchers in this field.

[0003] The prior art CN214937455U discloses a solid-state nano-pore gene pool and a sequencing device for solid-state nano-pores. This device optimizes the equipment through the upper main body and the lower fixing part in the upper liquid cell. It mainly uses the fixing step designed by the lower fixing part to pre-press the nano-pore chip and the upper sealing flat gasket, obtaining better sealing performance than the adhesive layer, avoiding the mixing of impurities in gene detection, improving the detection accuracy, having good sealing performance during detection, and being able to directly assemble each component to obtain a finished product, with relatively convenient and fast assembly. However, considering the complex circuit measurement process and the environmental conditions for electrode signal acquisition, the stability and accuracy of its sequencing device are limited. At the same time, this sequencing device mainly focuses on improving the detection sealing performance, and there are slight deficiencies in the prior art in realizing the acquisition and analysis of the overall sequence signal.

[0004] The prior art CN205710714U provides a nanopore chip fixture. By improving the structure of the nanopore chip fixture, changing the sealing method, and adding electrode plates, problems such as difficult positioning and clamping of the nanopore chip, poor reagent sealing, and inability to measure lateral signals are well solved. However, this device is directly processed from an opaque cylinder, unable to observe the chip assembly situation in real time, and there are only reagent inlet and outlet holes with relatively small diameters at the bottom of the frustum, which are prone to generating bubbles that cannot be observed during the detection process, and it is impossible to detect and remove the bubbles in time, requiring multiple measurements for verification. At the same time, it is mainly fixed by screws, prone to dislocation, and the accuracy and measurement efficiency of the device are relatively low. In terms of the accuracy and efficiency of experimental measurement, the prior art appears to be slightly insufficient.

[0005] The prior art CN216688083U discloses a micro-nano detection liquid cell device for a nanopore sensor, which mainly consists of two differently shaped liquid cells for positioning, one convex and one concave, a rubber gasket for sealing, an external bolt frame for clamping the liquid cells, and locking screws. It has better sealing performance and assembly stability, improving the detection accuracy. At the same time, the transparent base material of this device is easier to observe the usage state, and relevant problems existing in the experiment can be detected in time. However, during the detection process, the electrodes are directly inserted into the liquid cell from the injection hole, there is a certain instability, so the pore design of the liquid cell module needs to be improved. Summary of the Invention

[0006] Purpose of the Invention: To solve the problems existing in the prior art, the present invention provides a nanopore micro-nano detection liquid cell device suitable for circuit measurement, which improves the fluidity of the liquid cell channel and the stability of electrode measurement, reduces the damage to the chip caused by repeated disassembly, improves the yield rate of assembly, saves time and cost, and better realizes measurement stability and accuracy.

[0007] Technical Solution: A nanopore micro-nano detection liquid cell device suitable for circuit measurement includes a first nanopore liquid cell base, a second nanopore liquid cell base, a chip, a sealing element, and a fastening element. The first nanopore liquid cell base and the second nanopore liquid cell base are assembled through a connecting member. A first middle through hole is provided in the middle of the first nanopore liquid cell base, and a second middle through hole is provided in the middle of the second nanopore liquid cell base. The chip and the sealing element are arranged between the first middle through hole and the second middle through hole; it also includes a measurement electrode. The first nanopore liquid cell base is provided with a first injection hole and a second injection hole, and the second nanopore liquid cell base is provided with a third injection hole and a fourth injection hole; both the first injection hole and the second injection hole are inclined and communicate with the first middle through hole respectively, and both the third injection hole and the fourth injection hole are inclined and communicate with the second middle through hole respectively; a first electrode hole communicates with the first injection hole, and a second electrode hole communicates with the third injection hole. The first electrode hole and the second electrode hole are respectively provided with a measurement electrode.

[0008] Further, the inner diameters of the first injection hole and the second injection hole gradually decrease along the direction from the center to the outer edge of the first nanopore liquid pool base;

[0009] The inner diameters of the third injection hole and the fourth injection hole gradually decrease along the direction from the center to the outer edge of the second nanopore liquid pool base.

[0010] Further, the first intermediate through hole and the second intermediate through hole are concentric and coaxial.

[0011] Further, a cylindrical boss is provided on each side of the first intermediate through hole, and a groove matching the boss is provided on each side of the second intermediate through hole.

[0012] Further, the materials of the first nanopore liquid pool base and the second nanopore liquid pool base are colorless plexiglass respectively.

[0013] Further, the inclination angles of the first injection hole, the second injection hole, the third injection hole and the fourth injection hole are all 30°, and they respectively have the functions of liquid injection and liquid storage.

[0014] Further, the inner diameter of the first electrode hole gradually decreases along the direction from the center to the outer edge of the first nanopore liquid pool base;

[0015] The inner diameter of the second electrode hole gradually decreases along the direction from the center to the outer edge of the second nanopore liquid pool base.

[0016] Further, the measurement electrode is composed of an Ag / AgCl wire, a polytetrafluoroethylene cap and a metal head, where: the length of the Ag / AgCl wire is 45 mm and the width is 0.5 mm; the length of the polytetrafluoroethylene cap is 25 mm and the width is 5.8 mm; the length of the metal head is 8 mm and the width is 1.3 mm.

[0017] The beneficial effects of the present utility model are as follows:

[0018] 1. The present invention separately designs an electrode measurement channel and connects it to the liquid injection channel. By directly fixing the electrode to the electrode measurement channel, more stable measurement of the sample can be carried out, reducing the uncertainty of environmental factors such as contamination and bubbles caused by repeated insertion of the electrode into the liquid. At the same time, the electrode is directly embedded at the bottom of the electrolyte solution for stable contact, reducing the instability of the liquid surface contact, and further improving the stability and accuracy of the measurement;

[0019] 2. The present invention designs a straight four-channel liquid injection channel with a certain inclination angle, where two channels are dedicated to adding samples, and two channels are embedded with electrode measurement channels. At the same time, the channels on one side are connected and flow, which can reduce the generation of bubbles and make it more convenient to discharge the bubbles. It can keep the wetting state of the nanopore chip throughout the assembly process, further improving the yield rate of the finished product; each liquid injection channel adopts a variable-size pipeline for linear connection and reaches the chip directly at the same inclination angle, increasing the conductivity of the solution; in addition, the four-channel liquid injection channel also facilitates the discharge of the electrolyte solution of the measured sample, and the sample and the electrolyte solution can be replaced without disassembly, reducing the number of disassembly times, reducing the wear on the chip, shortening the experimental time, and improving the research efficiency;

[0020] 3. The present invention adopts a multi-stage sealing structure for two modules. In addition to the fitting of the convex and concave parts of the conventional chip embedded part, a cylindrical key structure is designed in the module to fix the two liquid pool modules, preventing the rotation of the central chip connection part during the assembly of the two liquid pool modules, reducing the wear on the nanopore chip, and reducing the use cost. At the same time, after the two liquid pool modules are assembled, a sealing ring is added around the periphery to further improve the fixation and assembly integrity of the liquid pool, improve the stability of the liquid pool, and facilitate portability and movement;

[0021] 4. The present invention adopts a modular design, which can directly assemble each component, improving the experimental efficiency. At the same time, the transparent base material is easier to observe the use state. Once a problem is found with the nanopore chip, the problem can be directly investigated. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a preliminary assembly sectional view of the present utility model, without assembling the test electrode and the fastening element;

[0023] Figure 2 It is an overall assembly sectional view of the present utility model, assembled with a test electrode and a fastening element;

[0024] Figure 3 It is a schematic structural diagram of the first nanopore liquid pool base of the present utility model;

[0025] Figure 4 It is a schematic structural diagram of the second nanopore liquid pool base of the present utility model;

[0026] Figure 5 It is a front view of the preliminary assembled linear flow channel of the present utility model;

[0027] Figure 6 It is an internal sectional view of the second nanopore liquid pool base of the present utility model;

[0028] Figure 7(a) is a diagram showing the measurement electrode of the present utility model stored in a glass tube, and Figure 7(b) is an overall diagram of the measurement electrode of the present utility model after being taken out;

[0029] Figure 8 is an overall schematic diagram of the fastening element of the present utility model;

[0030] 1 - First nanopore liquid cell base, 2 - Second nanopore liquid cell base, 3 - Chip, 4 - Sealing element, 5 - First intermediate through hole, 6 - Second intermediate through hole, 7 - First connection, 8 - Second connection, 9 - First injection hole, 10 - Second injection hole, 11 - Third injection hole, 12 - Fourth injection hole, 13 - First electrode hole, 14 - Second electrode hole, 15 - Fastening element, 16 - Measurement electrode. Detailed implementation manners

[0031] The technical solution of the present utility model will be described in detail below with reference to the accompanying drawings of the specification and the specific implementation manners.

[0032] In the following description, many specific details are set forth in order to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0033] Secondly, the so-called "one embodiment" or "embodiment" herein refers to a specific feature, structure or characteristic that can be included in at least one implementation manner of the present invention. The appearances of "in one embodiment" in different places in this specification do not all refer to the same embodiment, nor are they separate or alternative embodiments that exclude each other with other embodiments.

[0034] Furthermore, the present invention is described in detail with reference to the schematic diagrams. When describing the embodiments of the present invention in detail, for the convenience of explanation, the cross-sectional views showing the device structure will be enlarged locally not in accordance with the general ratio, and the schematic diagrams are only examples and should not limit the scope of protection of the present invention herein. In addition, in actual production, three-dimensional spatial dimensions including length, width and depth should be included.

[0035] The present invention provides a micro-nano detection liquid cell device for a nanopore sensor applicable to a measurement circuit to solve the problems in the prior art that due to the process design reasons of the liquid cell assembly, the sealing effect of the detection liquid cell is poor and the assembly efficiency is low. And by designing the electrode channels, the instability during measurement and the uncertainty of environmental factors are reduced.

[0036] Such as Figure 1 、 Figure 2 、 Figure 4As shown, the detection liquid pool device includes a first nanopore liquid pool base 1, a second nanopore liquid pool base 2, a chip 3, a sealing element 4, a fastening element 15 and a measuring electrode 16. The first nanopore liquid pool base 1 and the second nanopore liquid pool base 2 constitute the shell of the micro-nano detection liquid pool; Figure 3 , Figure 4 As shown, the first nanopore liquid pool base 1 and the second nanopore liquid pool base 2 are respectively provided with a first middle through hole 5 and a second middle through hole 6 that can correspond to each other, and the first middle through hole 5 and the second middle through hole 6 are coaxial and concentric to ensure that the hole positions correspond to each other without misalignment. Figure 5 As shown, the chip 3 and the sealing element 4 are arranged between the first middle through hole 5 and the second middle through hole 6. A through hole is arranged in the center of the sealing element 4, which ensures that both sides of the chip 3 can contact the test liquid and prevents the test liquid from leaking.

[0037] Furthermore, the first middle through hole 5 is connected to the first injection hole 9 and the second injection hole 10, the second middle through hole 6 is connected to the third injection hole 11 and the fourth injection hole 12, the first injection hole 9, the second injection hole 10, the third injection hole 11, and the fourth injection hole 12 are all arranged at an angle and pass through the first nanopore liquid pool base 1 and the second nanopore liquid pool base 2 respectively. The staff injects the test liquid into the second injection hole 10 and the fourth injection hole 12. The test liquid slowly enters the first middle through hole 5 and the second middle through hole 6 and then contacts the two sides of the chip 3, and gradually enters the first injection hole 9, the third injection hole 11 and the first electrode hole 13 and the second electrode hole 14. Preferably, the first injection hole 9, the second injection hole 10, the third injection hole 11 and the fourth injection hole 12 are all inclined. Compared with the vertical setting, the angle setting can ensure that the test liquid flows as close to the wall as possible during the injection process, reducing detection interference factors such as splashing and bubbles. Preferably, the inclination angle is 30°; the diameters of the first injection hole 9, the second injection hole 10, the third injection hole 11 and the fourth injection hole 12 are all 2.5 mm, with liquid injection and storage functions, which is convenient for removing gas. Figure 5 As shown, the flow channels of the first injection hole 9 and the third injection hole 11 are linearly connected by pipes of different sizes, and the same inclination angle directly reaches the chip, which increases the conductivity of the solution (compared with the L-shaped equal-bend pipe design); similarly, the flow channels of the second injection hole 10 and the fourth injection hole 12 are linearly connected by pipes of different sizes, and the same inclination angle directly reaches the chip.

[0038] Furthermore, the first electrode hole 13 is connected to the first injection hole 9, and the second electrode hole 14 is connected to the third injection hole 11 (eg Figure 6As shown, such a hole position setting can ensure stable contact between the electrode and the test solution during the test compared with directly placing the electrode in the test solution in the injection hole, reducing the environmental interference factors during the measurement of the electrode; the first electrode hole 13 and the second electrode hole 14 have the function of storing liquid, facilitating the full contact between the electrode (such as Figure 7(a) , 7(b) as shown) and the test solution.

[0039] Further preferably, the inner diameters of the first injection hole 9, the second injection hole 10, the third injection hole 11, and the fourth injection hole 12 gradually decrease along the direction from the center to the outer edge of the first nanopore liquid cell base 1 or the second nanopore liquid cell base 2. When the test solution flows to the first injection hole 9, the second injection hole 10, the third injection hole 11, the fourth injection hole 12, the first electrode hole 13, and the second electrode hole 14, it will further expel air, ensuring that there is no bubble mixing interference when the test solution contacts the chip 3, and reducing the bubbles in the pore channels. The insulating liquid cell of the first nanopore liquid cell base 1 or the second nanopore liquid cell base 2 is preferably made of colorless plexiglass, making the detection process visual, more conducive to timely problem discovery, achieving the transparency and visibility of the overall structure and controllable operation. The sealing element 4 can be a sealing gasket or a sealing strip, such as a rubber / silicone gasket, and is pre-compressed at the placement location.

[0040] For easy disassembly and assembly, the first connection 7 is two cylindrical bosses provided on the first nanopore liquid cell base 1 on both sides of the first intermediate through hole 5, and the second connection 8 is a groove provided on the second nanopore liquid cell base 2 on both sides of the second intermediate through hole 6 and matching the cylindrical bosses, facilitating the positioning connection of the two bases. After the two are connected, the first nanopore liquid cell base 1 and the second nanopore liquid cell base 2 can be assembled. After the assembly is completed, the first nanopore liquid cell base 1 and the second nanopore liquid cell base 2 are fastened through the fastening element 15 to ensure the complete connection of the assembly connection and meet the use requirements under the moving state. Since the micro-nano detection liquid cell is assembled and connected, after several replacements of the samples to be tested or the chip 3, the fixed connection method of the fastening element 15 can further ensure the tightness, reliability, and stability of the micro-nano detection liquid cell after multiple assemblies, and it can be moved freely. The fastening element 15 can be further elongated to penetrate through the second nanopore liquid cell base 2.

[0041] Furthermore, the first nanopore liquid cell base 1 and the second nanopore liquid cell base 2 are initially fixed through the connection of the bosses and the grooves and the fastening element 15. And the designed connection part does not need to be concavo-convexly fitted at the chip, reducing the wear degree of the chip during assembly and extending the service life of the chip.

[0042] In summary, the present invention adopts a four-channel design, which increases the fluidity of the liquid to be measured and reduces the disassembly of the device; at the same time, a dedicated channel is used for sample addition and electrode measurement, reducing uncertain factors such as contamination and interference. The flow channels are linearly connected by pipes of different sizes and reach the chip directly at the same inclination angle, increasing the conductivity of the solution. The structure of the same-side flow channel conduction can better complete liquid replacement and flushing, with high repeatability and stability; the structure design of the two-side electrode channels enables stable contact at the solid-liquid interface of the electrodes and more stable measurement; a cylindrical lock-and-key structure is used to fix between the two nanopore liquid cell bases, which can reduce rotation and improve the assembly efficiency; further fixation is achieved by using an external sealing ring (such as Figure 8 as shown), enabling free movement.

[0043] The micro-nano detection liquid cell device of the nanopore sensor in the present invention has better sealing performance, measurement stability and detection efficiency. The present invention separately designs an electrode measurement channel, and the sample can be measured more stably by directly fixing the electrode to the electrode measurement channel, further improving the stability and accuracy of the measurement; on the other hand, the present invention designs a four-channel liquid injection channel, which can reduce the generation of bubbles, keep the nanopore chip in a wet state throughout the assembly process, further improve the yield of the finished product. In addition, the four-channel liquid injection channel also facilitates the discharge of the electrolyte solution of the measurement sample, and the sample and the electrolyte solution can be replaced without disassembly, reducing the number of disassembly times, reducing the wear of the chip, and improving the research efficiency; the modular design can directly assemble each component, improving the experimental efficiency. At the same time, the transparent base material is easier to observe the usage state, and once a problem is found with the nanopore chip, the problem can be directly investigated.

Claims

1. A nano-pore micro-nano detection liquid cell device applicable to circuit measurement, comprising a first nano-pore liquid cell base (1), a second nano-pore liquid cell base (2), a chip (3), a sealing element (4), and a fastening element (15). The first nano-pore liquid cell base (1) and the second nano-pore liquid cell base (2) are assembled through a connecting member. A first intermediate through-hole (5) is provided in the middle of the first nano-pore liquid cell base (1), and a second intermediate through-hole (6) is provided in the middle of the second nano-pore liquid cell base (2). The chip (3) and the sealing element (4) are arranged between the first intermediate through-hole (5) and the second intermediate through-hole (6); it is characterized in that, It further includes a measuring electrode (16). A first injection hole (9) and a second injection hole (10) are provided in the first nanopore liquid cell base (1), and a third injection hole (11) and a fourth injection hole (12) are provided in the second nanopore liquid cell base (2); the first injection hole (9) and the second injection hole (10) are both inclined and communicate with the first intermediate through hole (5) respectively, and the third injection hole (11) and the fourth injection hole (12) are both inclined and communicate with the second intermediate through hole (6) respectively; a first electrode hole (13) communicates with the first injection hole (9), and a second electrode hole (14) communicates with the third injection hole (11), and the measuring electrode (16) is placed in the first electrode hole (13) and the second electrode hole (14) respectively.

2. The nano-pore micro-nano detection liquid cell device applicable to circuit measurement according to claim 1, wherein The inner diameters of the first injection hole (9) and the second injection hole (10) gradually decrease along the direction from the center of the first nanopore liquid cell base (1) to the outer edge. The inner diameters of the third injection hole (11) and the fourth injection hole (12) gradually decrease along the direction from the center of the second nanopore liquid cell base (2) to the outer edge.

3. The nano-pore micro-nano detection liquid cell device applicable to circuit measurement according to claim 1, characterized in that The first intermediate through hole (5) and the second intermediate through hole (6) are concentric and coaxial.

4. The nanopore micro-nano detection liquid cell device applicable to circuit measurement according to any one of claims 1-3, characterized in that, One cylindrical boss is provided on each side of the first intermediate through hole (5), and one groove matching the boss is provided on each side of the second intermediate through hole (6).

5. The nanopore micro-nano detection liquid cell device applicable to circuit measurement according to any one of claims 1-3, characterized in that, The materials of the first nanopore liquid cell base (1) and the second nanopore liquid cell base (2) are colorless organic glass respectively.

6. The nanopore micro-nano detection liquid cell device applicable to circuit measurement according to any one of claims 1-3, characterized in that, The inclination angles of the first injection hole (9), the second injection hole (10), the third injection hole (11) and the fourth injection hole (12) are all 30°, and they respectively have the functions of liquid injection and liquid storage.

7. The nano-pore micro-nano detection liquid cell device applicable to circuit measurement according to any one of claims 1-3, characterized in that, The inner diameter of the first electrode hole (13) gradually decreases along the direction from the center of the first nanopore liquid cell base (1) to the outer edge. The inner diameter of the second electrode hole (14) gradually decreases along the direction from the center of the second nanopore liquid cell base (2) to the outer edge.

8. The nanopore micro-nano detection liquid cell device applicable to circuit measurement according to any one of claims 1-3, characterized in that, The measuring electrode is composed of an Ag / AgCl wire, a polytetrafluoroethylene cap and a metal head. Among them: the length of the Ag / AgCl wire is 45 mm and the width is 0.5 mm; the length of the polytetrafluoroethylene cap is 25 mm and the width is 5.8 mm; the length of the metal head is 8 mm and the width is 1.3 mm.

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