Electrophoresis gene chip

Abstract

The utility model discloses an electrophoresis gene chip, which relates to the technical field of gene chips and comprises a substrate and a cover plate, nucleic acid probes are fixed at a plurality of positions on the upper surface of the substrate, a conductive coating is arranged on the lower surface of the substrate, and the substrate is used as a first electrode; the cover plate is positioned above the substrate; a plurality of strip electrodes are regularly arranged on the upper surface of the cover plate, and each strip electrode serves as a second electrode; the first electrode and the plurality of second electrodes are connected with an external power supply controller through leads; the first electrode and the plurality of second electrodes are used for alternately carrying positive and negative electricity under the control of the power supply controller, so that magnetic particles in the to-be-detected solution between the substrate and the cover plate move in a three-dimensional space between the substrate and the cover plate and are sequentially enriched in a corresponding area of each second electrode on the substrate; the to-be-detected solution contains sample nucleic acid combined with the magnetic particles. By adopting the electrophoresis gene chip, sample nucleic acid in a solution to be detected can be driven to move in a three-dimensional direction.

Description

Technical Field

[0001] The present application relates to the technical field of gene chips, and in particular to an electrophoresis gene chip. Background Art

[0002] The hybridization process of gene chip is a key factor affecting the quality of chip detection, and the effective contact between target and probe is the core of hybridization results.

[0003] In gene chips, probes can only appear in a very small space on the surface of the substrate, which is generally at the nanometer level. For example, the height of a standard B-type DNA double helix is ​​3.4 nanometers, which includes 10 base pairs. To ensure that the target is in better contact with the probe, it is necessary to ensure that the target appears at each probe position on the chip in order to achieve effective detection of the sample. The hybridization space of a general chip is 0.1 mm. In this hybridization space, only a few dozen nanometers close to the surface of the substrate are effective hybridizable targets. From 0.1 mm to 10 nanometers, the space compression must reach 10,000 times. If this degree of compression is achieved, it is equivalent to concentrating the sample 10,000 times, which will greatly improve the detection ability of the chip.

[0004] Traditional chip detection is mainly achieved by utilizing the free movement of the target, and most of them require a long hybridization process. The earliest gene chips used overnight hybridization. With the need for rapid detection, various technologies have emerged to effectively accelerate the hybridization process.

[0005] Electric field driven movement of charged particles is a commonly used acceleration technology that improves chip detection speed. However, traditional electrophoresis technology only solves directional movement in one dimension, and complex pulse alternating electric fields can achieve two-dimensional movement of charged particles. Utility Model Content

[0006] The embodiment of the present application provides an electrophoresis gene chip to solve the problem in the prior art of how to drive the sample nucleic acid to move in three dimensions in gene chip detection.

[0007] The embodiment of the present application provides an electrophoresis gene chip, comprising: a substrate and a cover plate;

[0008] Nucleic acid probes are fixed at multiple positions on the upper surface of the substrate, the lower surface of the substrate has a conductive coating, and the substrate serves as a first electrode;

[0009] The cover plate is located above the substrate, and there is a gap between the cover plate and the substrate;

[0010] A plurality of strip-block electrodes are regularly arranged on the upper surface of the cover plate, and each strip-block electrode serves as a second electrode;

[0011] The first electrode and the plurality of second electrodes are connected to an external power controller via leads;

[0012] The first electrode and the plurality of second electrodes are used to carry positive and negative charges alternately under the control of the power controller, so that the magnetic particles in the solution to be detected between the substrate and the cover plate move in the three-dimensional space between the substrate and the cover plate, and are sequentially enriched in the corresponding area of ​​each second electrode on the substrate, and the solution to be detected contains sample nucleic acids bound to the magnetic particles.

[0013] Furthermore, the first electrode is conductive and light-transmitting glass;

[0014] The second electrode is a graphite electrode.

[0015] Furthermore, a plurality of strip electrodes are prepared on the upper surface of the cover plate by using screen printing technology.

[0016] Furthermore, the plurality of strip-block electrodes have the same shape and are arranged in a fence shape on the upper surface of the cover plate.

[0017] Furthermore, the plurality of strip electrodes are arranged in two rows in a fence shape on the upper surface of the cover plate.

[0018] The beneficial effects of this application include:

[0019] The electrophoresis gene chip provided in the embodiment of the present application includes a substrate and a cover plate, wherein nucleic acid probes are fixed at multiple positions on the upper surface of the substrate, the lower surface of the substrate has a conductive coating, the substrate serves as a first electrode, the cover plate is located above the substrate, and there is a gap between the cover plate and the substrate, a plurality of strip electrodes are regularly arranged on the upper surface of the cover plate, each of the strip electrodes serves as a second electrode, the first electrode and the plurality of second electrodes are connected to an external power controller through leads, the first electrode and the plurality of second electrodes are used to alternately carry positive and negative charges under the control of the power controller, so that the magnetic particles in the solution to be detected between the substrate and the cover plate move in the three-dimensional space between the substrate and the cover plate, and are sequentially enriched in the corresponding area of ​​each second electrode on the substrate, and the solution to be detected contains sample nucleic acids bound to the magnetic particles. Since a plurality of second electrodes are arranged on the upper cover plate and a first electrode is arranged on the lower substrate in the three-dimensional space between the substrate and the cover plate, an electric field is formed in the three-dimensional space by controlling the first electrode and the plurality of second electrodes to alternately carry positive and negative charges, and the direction of the electric field can be changed, thereby realizing the formation of electric fields in different directions of the three-dimensional space in sequence, thereby being able to drive the movement of the sample nucleic acid in the solution to be detected in the three-dimensional direction.

[0020] Other features and advantages of the present application will be described in the following description, and partly become apparent from the description, or be understood by practicing the present application. The purpose and other advantages of the present application can be realized and obtained by the structures specifically pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings are used to provide a further understanding 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 application and do not constitute a limitation of the present application. In the accompanying drawings:

[0022] Figure 1 A top view of the cover plate of the electrophoresis gene chip provided in an embodiment of the present application;

[0023] Figure 2 A schematic diagram of the front structure of the electrophoresis gene chip provided in the embodiment of the present application;

[0024] Figure 3 A top view of a cover plate of an electrophoresis gene chip provided in another embodiment of the present application;

[0025] Figure 4 A schematic diagram of the structure of a side surface of an electrophoresis gene chip provided in another embodiment of the present application;

[0026] Figure 5 A top view of a cover plate of an electrophoresis gene chip provided in another embodiment of the present application. DETAILED DESCRIPTION

[0027] In order to provide an implementation scheme for driving sample nucleic acid to move in three dimensions in gene chip detection, the present application embodiment provides an electrophoresis gene chip. The preferred embodiments of the present application are described below in conjunction with the drawings of the specification. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application. In addition, the embodiments and features in the embodiments of the present application can be combined with each other if there is no conflict.

[0028] The present application embodiment provides an electrophoresis gene chip, such as Figure 1 and Figure 2 As shown, it includes: a substrate 10 and a cover plate 20;

[0029] Nucleic acid probes are fixed at multiple positions on the upper surface of the substrate 10, and the lower surface of the substrate 10 has a conductive coating, and the substrate 10 serves as a first electrode;

[0030] The cover plate 20 is located above the substrate 10 and has a gap between the cover plate 20 and the substrate 10;

[0031] A plurality of strip-block electrodes are regularly arranged on the upper surface of the cover plate 20, and each strip-block electrode serves as a second electrode;

[0032] The first electrode and the plurality of second electrodes are connected to an external power controller via leads (not shown in the figure);

[0033] The first electrode and the plurality of second electrodes are used to alternately carry positive and negative charges under the control of a power controller, so that the magnetic particles in the solution to be detected between the substrate 10 and the cover plate 20 move in the three-dimensional space between the substrate 10 and the cover plate 20, and are sequentially enriched in the corresponding area of ​​each second electrode on the substrate 10, and the solution to be detected contains sample nucleic acids bound to the magnetic particles.

[0034] Using the electrophoresis gene chip provided in the embodiment of the present application, since in the three-dimensional space between the substrate and the cover plate, a plurality of second electrodes are arranged on the upper cover plate, and a first electrode is arranged on the lower substrate, therefore, by controlling the first electrode and the plurality of second electrodes to alternately carry positive and negative charges, an electric field is formed in the three-dimensional space, and the direction of the electric field can be changed, thereby realizing the formation of electric fields in different directions of the three-dimensional space in sequence, thereby being able to drive the movement of the sample nucleic acid in the solution to be detected in the three-dimensional direction.

[0035] Furthermore, driving the sample nucleic acid to move in three dimensions can more fully move the sample nucleic acid and sequentially enrich it in the corresponding area of ​​each second electrode on the substrate, that is, enrich it in a smaller area. Compared with the enrichment of the sample nucleic acid on the entire substrate, the nucleic acid concentration is increased, thereby improving the efficiency of hybridization between the sample nucleic acid and the probe on the substrate, thereby improving the detection capability and efficiency of the gene chip.

[0036] In one embodiment of the present application, the first electrode can be a conductive light-transmitting glass, for example, the substrate is made of ITO glass, which does not require the use of complex electronic circuit manufacturing technology and can be used as a whole sheet, and the aldehyde-based substrate is directly manufactured after APTES functionalization modification, and the upper surface of the substrate 10 is arranged with a probe microarray;

[0037] The second electrode may be a graphite electrode, that is, made of graphite conductive material.

[0038] In one embodiment of the present application, the substrate 10 and the cover plate 20 are both in the shape of flat plates, and accordingly, the first electrode can be a chip flat plate electrode; the cover plate 20 having a plurality of strip electrodes can be used as a graphite electrode flat plate.

[0039] In one embodiment of the present application, a plurality of strip electrodes may be prepared on the upper surface of the cover plate 20 by using screen printing technology.

[0040] In one embodiment of the present application, Figure 1 As shown, the plurality of strip electrodes have the same shape and can be arranged in a fence shape on the upper surface of the cover plate 20 .

[0041] Further, such as Figure 3 As shown, a plurality of strip electrodes may be arranged in two rows in a fence shape on the upper surface of the cover plate 20 .

[0042] The electrophoresis gene chip provided in the embodiments of the present application may be implemented in a boxed chip structure.

[0043] By using the above-mentioned electrophoresis gene chip provided in the embodiment of the present application, the first electrode and multiple second electrodes can be controlled to exchange positive and negative charges through a power controller, thereby forming an electric field in the three-dimensional space between the cover plate and the substrate, and the direction of the electric field can change, so that the electric field is formed in different directions in the three-dimensional space in sequence, thereby being able to drive the sample nucleic acid in the solution to be detected to move in the three-dimensional direction.

[0044] Based on the above Figure 3 The electrophoresis gene chip shown has two rows of multiple fence-shaped second electrodes, and the process of controlling the first electrode and the multiple second electrodes to exchange positive and negative charges is described in detail.

[0045] In one embodiment of the present application, Figure 3 As shown, the multiple second electrodes of the electrophoresis gene chip include second electrode 1, second electrode 2, second electrode 3, second electrode 4, second electrode 5, second electrode 6, etc. The other second electrodes shown in the figure can be arranged in sequence, which is not shown in the figure.

[0046] Step 1: First, the first electrode (i.e., the chip plate electrode serving as the substrate) is controlled to be positively charged, and the multiple second electrodes on the cover plate (graphite electrode plate) are all negatively charged, so that the sample nucleic acid (bound with magnetic particles) in the solution to be detected in the gene chip, under the action of the electric field force, all moves toward the chip plate electrode and is enriched on the chip plate electrode. A probe microarray is provided on the chip plate electrode. When the sample nucleic acid contains a target, the target contacts the probe, and specific binding occurs and the target is fixed to the probe.

[0047] In this first step, since it is the initial hybridization, the sample nucleic acid is dispersed in various spatial locations and is not concentrated or enriched. The hybridization is random, so the probability of binding is not high.

[0048] Step 2: Adjust the power supply state of the circuit so that the second electrode 1 of the graphite electrode plate is positively charged and the first electrode is negatively charged. Under the action of the electric field force, all sample nucleic acids are enriched on the second electrode 1 of the graphite electrode plate. Prolonging the electric field action time can ensure that all sample nucleic acids are enriched on the second electrode 1.

[0049] Step 3: Adjust the power supply state of the circuit so that the second electrode 1 of the graphite electrode plate is negatively charged and the first electrode is positively charged. At this time, the electric field between the second electrode 1 and its projection area in the electric field direction on the chip plate electrode is the strongest. The sample nucleic acid originally enriched on the second electrode 1 is directionally moved to the projection area of ​​the second electrode 1 in the electric field direction on the chip plate electrode (the projection area is the corresponding area of ​​the second electrode 1 on the substrate) under the action of the electric field force, and is identified and hybridized with the probe on the projection area of ​​the second electrode 1 in the electric field direction on the chip plate electrode. The nucleic acid target molecules that are specifically identified and bound are fixed on the probe by binding to the probe, and the nucleic acid molecules that cannot be specifically identified and bound are temporarily retained on the chip plate electrode.

[0050] Step 4: Adjust the power supply state of the circuit so that the second electrode 2 of the graphite electrode plate is positively charged and the chip plate electrode is negatively charged. The sample nucleic acid that has not undergone specific binding on the chip plate electrode is enriched toward the second electrode 2 of the graphite electrode plate under the action of the electric field force, and the nucleic acid that has completed specific hybridization binding continues to remain on the probe and no longer moves.

[0051] Step 5: Adjust the power supply state of the circuit so that the second electrode 2 of the graphite electrode plate is negatively charged and the chip plate electrode is positively charged. At this time, the electric field between the second electrode 2 and its projection area in the electric field direction on the chip plate electrode is the strongest. The sample nucleic acid originally enriched on the second electrode 2 is directionally moved to the projection area of ​​the second electrode in the electric field direction on the chip plate electrode (the projection area is the corresponding area of ​​the second electrode 2 on the substrate) under the action of the electric field force, and is identified and hybridized with the probe on the projection area of ​​the second electrode 2 in the electric field direction on the chip plate electrode. The nucleic acid target molecules that are specifically identified and bound are fixed on the probe by binding to the probe, and the nucleic acid molecules that cannot be specifically identified and bound are temporarily retained on the chip plate electrode.

[0052] Step 6: According to the above control ideas, by continuously changing the power supply state of the circuit, the sample nucleic acid is oscillated and moved between the graphite electrode plate and the chip plate electrode, ensuring that the enriched sample nucleic acid is hybridized with the probes in different areas of the substrate in turn according to the change of the electric field. The hybridized nucleic acid target is fixed to the probe and no longer moves. The nucleic acid target that has not undergone specific binding continues to move until it finds the corresponding probe and undergoes specific binding.

[0053] According to the control method of the above steps, Figure 3 As shown by the middle arrow, the sample nucleic acid can be controlled to be enriched in the corresponding area of ​​each second electrode on the substrate in sequence. Figure 4 The figure shows the longitudinal movement direction of the sample nucleic acid between the graphite electrode plate and the chip plate electrode;

[0054] According to other control methods based on the same principle, the following can also be achieved: Figure 5In the order shown by the arrows, the sample nucleic acid is controlled to be enriched in the corresponding area of ​​each second electrode on the substrate in turn.

[0055] Through continuous electric field changes, all nucleic acid molecules in the sample nucleic acid can be highly enriched and try to hybridize with all probes on the chip, improving the detection sensitivity and speed. By optimizing the electric field force, all non-specifically bound nucleic acids can be removed from the chip, reducing false positives. Driven by the electric field force, the enriched nucleic acids can pass through all positions on the chip, avoiding false negatives.

[0056] In the embodiment of the present application, by utilizing the cooperation between the positive and negative charges of the flat first electrode and the plurality of second electrodes, all sample nucleic acids in the electrophoresis gene chip can be enriched in the corresponding area of ​​a second electrode on the substrate, thereby greatly improving the local sample concentration. Calculated based on the area of ​​the second electrode being 1 / 40 of the area of ​​the substrate, when all sample nucleic acids within a 0.1 mm height of the chip are enriched on the surface of the strip (10 nm space), the concentration multiple of the sample nucleic acid can be 400,000 times of the original, thereby greatly improving the detection capability of the chip, and only a small amount of sample is needed to complete the detection.

[0057] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0058] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. An electrophoresis gene chip, It is characterized in that include: Substrate and cover plate; Nucleic acid probes are fixed at multiple positions on the upper surface of the substrate, the lower surface of the substrate has a conductive coating, and the substrate serves as a first electrode; The cover plate is located above the substrate, and there is a gap between the cover plate and the substrate; A plurality of strip-block electrodes are regularly arranged on the upper surface of the cover plate, and each strip-block electrode serves as a second electrode; The first electrode and the plurality of second electrodes are connected to an external power controller via leads; The first electrode and the plurality of second electrodes are used to carry positive and negative charges alternately under the control of the power controller, so that the magnetic particles in the solution to be detected between the substrate and the cover plate move in the three-dimensional space between the substrate and the cover plate, and are sequentially enriched in the corresponding area of ​​each second electrode on the substrate, and the solution to be detected contains sample nucleic acids bound to the magnetic particles.

2. The electrophoresis gene chip according to claim 1, It is characterized in that The first electrode is conductive and light-transmitting glass; The second electrode is a graphite electrode.

3. The electrophoresis gene chip according to claim 1, It is characterized in that The upper surface of the cover plate is prepared with a plurality of strip electrodes by using screen printing technology.

4. The electrophoresis gene chip according to claim 1, It is characterized in that The plurality of strip electrodes have the same shape and are arranged in a fence shape on the upper surface of the cover plate.

5. The electrophoresis gene chip according to claim 4, It is characterized in that The plurality of strip electrodes are arranged in two rows in a fence shape on the upper surface of the cover plate.

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