Sample injection chip and method based on electrophoresis technology

Abstract

The present invention provides a sample injection chip and a sample injection method based on electrophoresis technology, wherein the sample injection chip comprises a substrate and an electrode, wherein the substrate is made of insulating material; further comprising: a temporary storage module arranged on the substrate for temporarily storing samples; and the electrode is annular and arranged around the temporary storage module. The present invention has the advantages of requiring less samples and the like.

Description

Technical Field

[0001] The invention relates to pollution monitoring, and in particular to a sample injection chip and method based on electrophoresis technology. Background Art

[0002] Capillary electrophoresis is a widely used and efficient detection technology that can be applied to the separation and detection of a variety of inorganic and organic substances. The capillary electrophoresis injection process is one of the important steps that affect the reproducibility and sensitivity of the analysis, among which electrical injection is a widely used method. During the electrical injection process, the metal electrode needs to be inserted deeply into the liquid to be tested, and the voltage is applied to allow the charged substance to migrate into the separation tube to achieve the injection process. Limited by the existing electrical injection method, the volume of the substance to be detected must be greater than 10 microliters, while the actual capillary electrophoresis injection volume only requires 1-10 nanoliters, so the following problems will arise:

[0003] 1. Waste of some expensive samples;

[0004] 2. It is not possible to analyze trace samples;

[0005] 3. It is difficult to miniaturize the capillary electrophoresis instrument;

[0006] 4. Unable to connect to upstream micro-reaction system (microfluidics).

[0007] In addition, electrical injection requires adding electrodes to the sample to be tested so that a passage can be formed with the capillary during injection to achieve the injection of the sample to be tested. The main methods of electrical injection are:

[0008] 1. SCIEX places an electrode at a distance of about 2 mm at the injection end of the capillary. During injection, the electrode and the capillary are inserted into the liquid to be tested together to achieve electrical injection. However, this method is not suitable for the analysis of trace liquids.

[0009] 2. Thermo Fisher uses a method of fixing the tip of the capillary with a metal sleeve to allow the electrode and the capillary to enter the sample together. However, due to the large volume of the sleeve, a small amount of the liquid to be tested will be adsorbed into the sleeve, affecting subsequent analysis.

[0010] 3. Place the droplet on a metal plate for capillary electrosampling. However, since the metal plate has a strong inhibitory effect on many biological reactions, the connection with different upstream reactions is limited.

[0011] The method based on microfluidic chip can realize capillary electrophoresis analysis of micro-reaction system, but most of these chips require high-precision injection pumps as a power source to assist the injection of trace samples. This method not only requires additional equipment but also has poor repeatability. Summary of the invention

[0012] In order to solve the deficiencies in the above-mentioned prior art solutions, the present invention provides a sample injection chip based on electrophoresis technology.

[0013] The objective of the present invention is achieved through the following technical solutions:

[0014] A sample injection chip based on electrophoresis technology, the sample injection chip based on electrophoresis technology, the sample injection chip comprises a substrate and an electrode, the substrate is made of insulating material; the sample injection chip also comprises:

[0015] A temporary storage module, which is arranged on the substrate and is used for temporarily storing samples;

[0016] The electrode is ring-shaped and is arranged around the temporary storage module.

[0017] The object of the present invention is also to provide a sample injection method, which is achieved through the following technical solutions:

[0018] According to the sample injection method of the sample injection chip of the present invention, the sample injection method is:

[0019] The bottom end of the charged capillary contacts the sample in the temporary storage module;

[0020] An electric field is formed between the capillary and the electrode, and the sample in the temporary storage module contacts the electrode;

[0021] Under the action of the electric field, the sample enters the capillary.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. Small amount of sample used;

[0024] By using the temporary storage module and the electrode settings, the sample can be temporarily stored in the temporary storage module with only nanoliters. When the sample needs to be injected, the capillary electrophoresis technology can be used, which significantly reduces the amount of sample used.

[0025] 2. High throughput;

[0026] Multiple temporary storage modules are designed on the same chip to store different samples, and the capillary electrophoresis array is used to analyze multiple samples simultaneously, which significantly improves the analysis throughput.

[0027] 3. Simple structure and low cost;

[0028] Capillary electrophoresis technology is used to achieve nanoliter sample injection, without the need for expensive pumps, reducing structural complexity and cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The disclosure of the present invention will become easier to understand with reference to the accompanying drawings. It is easy for those skilled in the art to understand that these drawings are only used to illustrate the technical solution of the present invention and are not intended to limit the scope of protection of the present invention. In the drawings:

[0030] Figure 1 4 is a simplified structural diagram of a sample injection chip based on electrophoresis technology according to an embodiment of the present invention. DETAILED DESCRIPTION

[0031] Figure 1 The following description describes the optional embodiments of the present invention to teach those skilled in the art how to implement and reproduce the present invention. In order to teach the technical solution of the present invention, some conventional aspects have been simplified or omitted. It should be understood by those skilled in the art that variations or substitutions derived from these embodiments will be within the scope of the present invention. It should be understood by those skilled in the art that the following features can be combined in various ways to form multiple variations of the present invention. Thus, the present invention is not limited to the following optional embodiments, but is only limited by the claims and their equivalents.

[0032] Embodiment 1:

[0033] Figure 1 A schematic diagram of the structure of a sample injection chip based on electrophoresis technology according to an embodiment of the present invention is given. Figure 1 As shown, the sample injection chip based on electrophoresis technology includes:

[0034] A substrate 11, wherein the substrate 11 is made of insulating material, such as glass;

[0035] A temporary storage module 21, which is disposed on the substrate 11 and is used for temporarily storing samples;

[0036] The electrode 31 is disposed on the outside of the temporary storage module 21 .

[0037] In order to improve the sampling efficiency, the electrode 31 is further in a ring shape and is arranged around the temporary storage module 21 .

[0038] In order to prevent the sample from contacting the electrode during non-injection time, the sample injection chip further includes:

[0039] The hydrophobic layer 41 is disposed on the surface of the substrate between the temporary storage module 21 and the electrode 31 .

[0040] In order to reduce the amount of sample used, the complexity of the chip structure and the cost, further, the temporary storage module is a hydrophilic layer arranged on the surface of the substrate.

[0041] In order to reduce the amount of sample used, further, the temporary storage module is a groove formed on the substrate, the inner diameter of the groove increases from bottom to top, and the inner diameter of the electrode is larger than the maximum inner diameter of the groove.

[0042] In order to improve the sample analysis throughput, further, the temporary storage modules are multiple, and the electrodes surrounding each temporary storage module are connected.

[0043] In order to improve the sample analysis throughput, the sample injection chip further includes:

[0044] One or more first connection parts 32, a plurality of temporary storage modules 21 are respectively arranged on both sides of the first connection parts 32, and the electrodes 31 surrounding the temporary storage modules 21 are connected to the first connection parts 32;

[0045] The second connection portion 33 , wherein the first connection portion 32 is connected to the second connection portion 33 .

[0046] The sample injection method according to the embodiment of the present invention, that is, the working method of the sample injection chip according to the embodiment of the present invention, is as follows:

[0047] The bottom end of the charged capillary contacts the sample in the temporary storage module;

[0048] An electric field is formed between the capillary and the electrode, and the sample in the temporary storage module contacts the electrode;

[0049] Under the action of the electric field, the sample enters the capillary.

[0050] Embodiment 2:

[0051] An application example of the sample injection chip and injection method based on electrophoresis technology according to Example 1 of the present invention.

[0052] In this application example, Figure 1 As shown, the substrate 11 is made of insulating glass, and a first connecting portion 32, a second connecting portion 33 and a plurality of annular electrodes 31 are formed on the surface of the substrate 11 by sputtering or the like. The plurality of annular electrodes 31 are respectively located on both sides of the first connecting portion 32 and connected to the first connecting portion 32, and the plurality of first connecting portions 32 are connected to the second connecting portions 33;

[0053] The structure of the temporary storage module 21 is as follows: a groove is machined on the base 11 on the inner side of the annular electrode 31, and the inner diameter of the groove increases from bottom to top, and the inner diameter of the annular electrode 31 is larger than the maximum inner diameter of the groove (the inner diameter of the top of the groove); a hydrophobic layer 41 is set in the area of ​​the groove adjacent to the electrode 31 to prevent the sample from contacting the electrode 31 when not injecting.

[0054] It can be seen that, by utilizing the configuration of the temporary storage module 21 and the electrode 31 , the injection of nanoliter liquid samples is achieved without the need for a pump.

[0055] The sample injection method according to the embodiment of the present invention, that is, the working method of the sample injection chip according to the embodiment of the present invention, is as follows:

[0056] The bottom ends of the plurality of charged capillaries arranged in a matrix are respectively in contact with the samples in the plurality of temporary storage modules 21 on the substrate 11;

[0057] An electric field is formed between the capillary and the electrode 31 , and the sample in the temporary storage module 21 passes over the hydrophobic layer 41 and contacts the electrode 31 ;

[0058] Under the action of the electric field, the sample enters the capillary, thereby achieving simultaneous injection of multiple capillaries and significantly improving injection throughput.

[0059] Embodiment 3:

[0060] The application example of the sample injection chip according to embodiment 1 of the present invention is different from embodiment 2 in that:

[0061] 1. The structure of the temporary storage module is: a hydrophilic layer distributed in a matrix is ​​arranged on the surface of the substrate, an electrode is arranged on the hydrophilic layer, and a hydrophobic layer is arranged between the hydrophilic layer and the electrode.

[0062] 2. The electrode is non-annular, such as fan-shaped, disposed on the outside of the hydrophobic layer and connected to the first connecting portion.

Claims

1. A sample injection chip based on electrophoresis technology, the sample injection chip comprising a substrate and an electrode, the substrate being made of insulating material; characterized in that: The sample injection chip also includes: A temporary storage module, which is arranged on the substrate and is used to temporarily store nanoliter samples; when injecting samples, the bottom end of the charged capillary contacts the nanoliter sample in the temporary storage module, an electric field is formed between the capillary and the electrode, and the sample in the temporary storage module passes through the hydrophobic layer and contacts the electrode; The electrodes are arranged around the outer side of the temporary storage module; A hydrophobic layer is disposed on the surface of the substrate between the temporary storage module and the electrode and surrounds the temporary storage module.

2. The sample injection chip according to claim 1, characterized in that: The temporary storage module is a hydrophilic layer arranged on the surface of the substrate.

3. The sample injection chip according to claim 1, characterized in that: The temporary storage module is a groove formed on the substrate, and the inner diameter of the groove increases from bottom to top, and the inner diameter of the electrode is larger than the maximum inner diameter of the groove.

4. The sample injection chip according to claim 1, characterized in that: There are multiple temporary storage modules, and the electrodes surrounding each temporary storage module are connected.

5. The sample injection chip according to claim 4, characterized in that: The sample injection chip also includes: One or more first connection parts, a plurality of temporary storage modules are respectively arranged on both sides of the first connection parts, and electrodes surrounding the temporary storage modules are connected to the first connection parts; A second connection portion, wherein the first connection portion is connected to the second connection portion.

6. The sample injection method of the sample injection chip according to any one of claims 1 to 5, wherein the sample injection method is: The bottom end of the charged capillary contacts the sample in the temporary storage module; An electric field is formed between the capillary and the electrode, and the sample in the temporary storage module contacts the electrode; Under the action of the electric field, the sample enters the capillary.

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