Bacteria separation chip and separation method

Abstract

The invention relates to a bacterial separation chip and a separation method, the bacterial separation chip comprises a chip body and a magnetic component, the chip body forms a separation flow channel, the separation flow channel is used for accommodating a sample, the magnetic component is connected to the chip body, at least part of the magnetic component is located in the separation flow channel and located on the inner wall surface of the separation flow channel, and the magnetic component is located in the chip body. The magnetic component is used for capturing bacteria in a sample, a shearing fluid is arranged in the separation flow channel, and separation particles are arranged in the sample, so that the bacteria in the sample move towards the inner wall surface of the separation flow channel under the action of the shearing fluid and the separation particles. According to the bacteria separation chip, directional movement of bacteria is achieved, and rapid capture and separation of the bacteria are achieved.

Description

Technical Field

[0001] The present application relates to the technical field of bacterial separation, and in particular to a bacterial separation chip and a separation method. Background Art

[0002] The premise of preventing and controlling pathogenic bacteria contamination in animal-derived food is to achieve rapid, sensitive and accurate detection of pathogens. The detection process of pathogens generally includes sample collection, pathogen isolation and pathogen detection. Among them, pathogen isolation is to separate high-purity and high-concentration target bacteria from complex samples, which seriously affects subsequent detection.

[0003] The concentration of bacteria to be tested in biological and food samples is often very low, so the conventional method generally uses a culture method to pre-enrich the bacteria for 8 to 18 hours, which greatly increases the overall detection time. In order to reduce the time for pathogen isolation. The rapid separation method in the related art mainly includes magnetic separation method, which constructs immunomagnetic beads to specifically select and capture target bacteria, and further applies a magnetic field to enrich magnetic bacteria, thereby achieving high-purity enrichment of pathogenic bacteria. However, the magnetic separation method in the related art requires repeated magnetic separation steps, and the magnetic separation device is often small, and the magnetic field action space is limited, resulting in a generally small sample volume. When the sample size is large, the effective separation of the target can only be achieved through multiple separations, and it is difficult to achieve rapid bacterial separation. The speed of bacterial separation needs to be improved. Summary of the invention

[0004] The embodiments of the present application provide a bacteria separation chip to at least partially solve the above technical problems.

[0005] In order to achieve the above object, according to the first aspect of the present application, a bacteria separation chip is provided, comprising:

[0006] A chip body, wherein the chip body is formed with a separation flow channel, and the separation flow channel is used to accommodate a sample;

[0007] A magnetic component connected to the chip body, at least part of which is located in the separation channel and on the inner wall surface of the separation channel, and is used to capture bacteria in the sample;

[0008] Wherein, a shear fluid is provided in the separation channel, and separation particles are provided in the sample, so that the bacteria in the sample move toward the inner wall surface of the separation channel under the action of the shear fluid and the separation particles.

[0009] Optionally, the shear fluid is a biocompatible liquid.

[0010] Optionally, the separation particles are polystyrene microspheres.

[0011] Optionally, the density of the separated particles is 1.05 g / cm 3 To 1.09g / cm 3 between; and / or,

[0012] The concentration of the separated particles is 3.5×10 12 / L to 5.5×10 12 Between 1 / L; and / or,

[0013] The size of the separated particles is between 6 μm and 8 μm.

[0014] Optionally, the magnetic component comprises an immunomagnetic bead chain, one end of the immunomagnetic bead chain is connected to the inner wall of the separation channel, and the other end of the immunomagnetic bead chain extends toward the center of the separation channel.

[0015] Optionally, the magnetic component includes at least two immunomagnetic bead chains, and the at least two immunomagnetic bead chains include a first immunomagnetic bead chain and a second immunomagnetic bead chain, and the first immunomagnetic bead chain and the second immunomagnetic bead chain are arranged opposite to each other.

[0016] Optionally, the number of the first immunomagnetic bead chains is multiple, the number of the second immunomagnetic bead chains is multiple, the multiple first immunomagnetic bead chains are arranged side by side, and the multiple second immunomagnetic bead chains are arranged side by side.

[0017] Optionally, the magnetic component also includes ferromagnetic material and a magnet, the ferromagnetic material is arranged on the outer wall of the chip body, the magnet is connected to the side of the ferromagnetic material facing away from the chip body, the ferromagnetic material and the magnet are used to construct a high-gradient magnetic field, and the immunomagnetic bead chain is located in the high-gradient magnetic field.

[0018] Optionally, an inlet communicating with the separation channel is formed at the first end of the chip body, and an outlet communicating with the separation channel is formed at the second end of the chip body.

[0019] According to the second aspect of the present application, a method for isolating bacteria is also provided, comprising:

[0020] Injecting a shear fluid into the separation flow channel of the chip body to form a shear flow field in the separation flow channel;

[0021] Arranging the immunomagnetic bead chain on the inner side wall of the separation channel, and constructing a high gradient magnetic field at the chip body so that the immunomagnetic bead chain is located in the high gradient magnetic field;

[0022] mixing the sample to be separated with the separation particles to obtain a mixed sample;

[0023] The mixed sample is injected into the separation channel, so that the bacteria in the mixed sample flow toward the edge of the separation channel under the action of the shear fluid and the separation particles.

[0024] In the bacterial separation chip of the embodiment of the present application, the sample and the separation particles are mixed and then injected into the separation channel, so that the mixture of the sample and the separation particles flows along the separation channel, and a shear fluid is provided in the separation channel. Under the action of the shear fluid, the bacteria in the sample will collide with the separation particles, so that the bacteria move to the edge of the separation channel, that is, the inner wall surface of the separation channel, under the action of the fluid shear force and the collision force of the separation particles, to achieve directional movement of the bacteria. At the same time, a magnetic component is provided on the inner wall surface of the separation channel, and when the bacteria move to the inner wall surface of the separation channel, the magnetic component can capture the bacteria in the sample. That is to say, the present application can move the bacteria in the sample to the inner wall surface of the separation channel through the combination of shear fluid and separation particles, so that the bacteria in the sample are concentrated on the inner wall surface of the separation channel, and the inner wall surface of the separation channel is provided with a magnetic component for capturing bacteria. The magnetic component can effectively capture the bacteria in the sample, thereby realizing rapid capture and separation of the bacteria. There is no need to repeatedly perform magnetic separation and capture on the bacteria in the sample. When capturing bacteria, the sample flows along the separation channel. Therefore, when the sample size is large, there is no need to separate it into multiple times, thereby improving the bacteria separation speed and reducing the detection cost.

[0025] Other features and advantages of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without creative work.

[0027] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings, wherein the same figure numbers represent the same parts in the following description.

[0028] Figure 1 is a schematic diagram of the structure of a bacteria separation chip provided in an exemplary embodiment of the present disclosure;

[0029] Figure 2 is a flow chart of a bacterial isolation method provided in an exemplary embodiment of the present disclosure.

[0030] Description of reference numerals:

[0031] 1. Chip body; 2. Magnetic component; 3. Separation particles; 4. Bacteria; 11. Separation channel; 12. Inlet; 13. Outlet; 21. Immunomagnetic bead chain; 22. Ferromagnetic material; 23. Magnet. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0033] According to the first aspect of this application, see Figure 1 The present disclosure provides a bacteria separation chip. The bacteria separation chip includes a chip body 1 and a magnetic component 2. The chip body 1 is formed with a separation channel 11, and the separation channel 11 is used to accommodate a sample. The magnetic component 2 is connected to the chip body 1, and at least part of the magnetic component 2 is located in the separation channel 11 and at the inner wall surface of the separation channel 11. The magnetic component 2 is used to capture bacteria 4 in the sample.

[0034] The separation channel 11 is provided with a shear fluid, and the sample contains separation particles 3 , so that the bacteria in the sample move toward the inner wall surface of the separation channel 11 under the action of the shear fluid and the separation particles 3 .

[0035] It can be understood that after the sample and separation particles 3 are mixed, they are injected into the separation channel 11, so that the mixture of the sample and separation particles 3 flows along the separation channel 11, and a shear fluid is provided in the separation channel 11. Under the action of the shear fluid, the bacteria 4 in the sample will collide with the separation particles 3, so that the bacteria 4 move toward the edge of the separation channel 11, that is, the inner wall surface of the separation channel 11, under the action of the fluid shear force and the collision force of the separation particles 3, so as to achieve the directional movement of the bacteria 4. At the same time, the inner wall surface of the separation channel 11 is provided with a magnetic component 2, and when the bacteria 4 move to the inner wall surface of the separation channel 11, the magnetic component 2 can capture the bacteria 4 in the sample. That is to say, the present application can move the bacteria 4 in the sample toward the inner wall surface of the separation channel 11 through the cooperation of the shear fluid and the separation particles 3, so that the bacteria 4 in the sample are concentrated on the inner wall surface of the separation channel 11, and the inner wall surface of the separation channel 11 is provided with a magnetic component 2 for capturing the bacteria 4. The magnetic component 2 can effectively capture the bacteria 4 in the sample, thereby realizing rapid capture and separation of the bacteria 4, without the need for repeated magnetic separation and capture of the bacteria 4 in the sample, and when capturing the bacteria 4, the sample flows along the separation channel 11, and when the sample volume is large, there is no need to separate it into multiple times, thereby improving the separation speed of the bacteria 4 and reducing the detection cost.

[0036] It is understandable that in the related art, when the volume of the sample is large, it is necessary to ensure the bacterial separation effect by increasing the magnetic field strength, increasing the number of immunomagnetic beads, etc., which leads to high costs. However, the present application, through the action of shear fluid and separation particles 3, can make the bacteria in the sample move to the inner wall surface of the separation channel 11 in a directional manner during the movement along the separation channel 11, and then the magnetic component 2 is set on the inner wall surface of the separation channel 11 to effectively capture the bacteria in the sample, thereby realizing the rapid and continuous flow separation of bacteria in large-volume samples.

[0037] It is understandable that the rapid flow of fluids in organisms can provide a reference for separating bacteria from large-volume samples. Blood and blood vessels form a complex and well-functioning fluid pathway, and the flow rate in arterial blood vessels can reach 180-220 mm / s (nearly 300 mL / min). In addition, blood is a viscous suspension composed of red blood cells, white blood cells and platelets, of which platelets of about 2 μm can adhere to the site of vascular injury through the edge effect, thereby achieving vascular healing. When a blood vessel is injured, in order to adhere to the injured surface, platelets must be close enough to the wound, that is, platelet marginalization. Platelet marginalization is caused by the interaction between platelets and red blood cells in the flowing blood. The collision between red blood cells and platelets caused by shear causes the circulating platelets to deviate toward the vascular wall. The platelets moving along the vascular wall are bound by adhesion proteins on the surface of the vascular wall. Therefore, platelets can achieve rapid movement toward the vascular wall at high shear speeds and adhere to the surface.

[0038] The separation particles 3 in the present application can be similar to red blood cells, the bacteria in the sample can be similar to platelets, and the magnetic component 2 can be similar to proteins on the surface of the blood vessel wall that can specifically adhere to platelets. In addition, submicron particles have no marginalization effect in red blood cell suspensions, while platelets are oblate spheroids with an aspect ratio of 1:2, which are close in size and shape to common bacteria (such as Escherichia coli and Salmonella), and can produce a significant marginalization effect. Therefore, by combining the shear fluid and the separation particles 3, it is possible to separate bacteria during the rapid flow of the sample, which is conducive to solving the bottleneck problem of slow sample flow rate in related technologies.

[0039] In some embodiments, the shear fluid is a biocompatible liquid, such as a phosphate buffer.

[0040] In some embodiments, the separation particles 3 are, for example, polystyrene microspheres.

[0041] In some embodiments, the density of the separation particles 3 is 1.05 g / cm 3 To 1.09g / cm 3 between.

[0042] It can be understood that when the density of the separated particles 3 is less than 1.05 g / cm 3 When the density of the separation particles 3 is too low, it is difficult to ensure sufficient collision with the bacteria in the sample, which may cause some bacteria to be unable to move to the inner wall of the separation channel 11 in a directional manner; when the density of the separation particles 3 is greater than 1.09 g / cm 3 When the density of the separation particles 3 is too high, it may affect the movement of bacteria, making it difficult for the bacteria to move to the inner wall of the separation channel 11. Therefore, the density of the separation particles 3 is set at 1.05 g / cm 3 To 1.09g / cm 3 The separation particles 3 can fully collide with the bacteria in the sample without affecting the movement of the bacteria, so that the bacteria can move in a directed manner to the inner wall surface where the separation is left.

[0043] In some examples, the density of the separated particles 3 is, for example, 1.05 g / cm 3 or 1.09 g / cm 3 .

[0044] In some embodiments, the concentration of the separated particles 3 is 3.5×10 12 / L to 5.5×10 12 Between pcs / L.

[0045] It can be understood that when the density of the separated particles 3 is less than 3.5×10 12 When the density of the separation particles 3 is greater than 5.5×10 / L, the density of the separation particles 3 is too low to ensure sufficient collision with the bacteria in the sample, which may cause some bacteria to be unable to move to the inner wall of the separation channel 11 in a directional manner. 12 When the density of the separation particles 3 is too high, the movement of bacteria may be affected, making it difficult for the bacteria to move to the inner wall of the separation channel 11. Therefore, the density of the separation particles 3 is set at 3.5×10 12 / L to 5.5×10 12 / L, so that the separation particles 3 can fully collide with the bacteria in the sample, while not affecting the movement of the bacteria, so that the bacteria can move directionally to the inner wall surface where the separation is left.

[0046] In some embodiments, the size of the separated particles 3 is between 6 μm and 8 μm.

[0047] It is understandable that the size of red blood cells in the blood is about 7 μm, so the present application sets the size of the separation particles 3 between 6 μm and 8 μm, so that the separation particles 3 in the shear fluid can be comparable to the red blood cells in the blood, ensuring that the separation particles 3 in the shear fluid can effectively collide with the bacteria, so that the bacteria can move in a directed manner toward the inner wall surface of the separation channel 11.

[0048] In some embodiments, see Figure 1 The magnetic component 2 includes an immunomagnetic bead chain 21 , one end of the immunomagnetic bead chain 21 is connected to the inner wall of the separation channel 11 , and the other end of the immunomagnetic bead chain 21 extends toward the center of the separation channel 11 .

[0049] It is understandable that the immunomagnetic bead chain 21 is set on the inner wall of the separation channel 11. Since the bacteria in the sample will flow to the inner wall of the separation channel 11 under the action of the shear fluid and the separation particles 3, the immunomagnetic bead chain 21 can capture the bacteria.

[0050] It can be understood that the immunomagnetic bead chain 21 is a collection of ferromagnetic particles modified with antibodies or aptamers or other recognition factors that can specifically recognize target bacteria, forming a chain structure under the action of a strong magnetic field.

[0051] In some embodiments, see Figure 1 The magnetic component 2 includes at least two immunomagnetic bead chains 21, and the at least two immunomagnetic bead chains 21 include a first immunomagnetic bead chain 21 and a second immunomagnetic bead chain 21. The first immunomagnetic bead chain 21 and the second immunomagnetic bead chain 21 are arranged opposite to each other.

[0052] It can be understood that the separation channel 11 includes a first inner side wall and a second inner side wall that are arranged oppositely, one end of the first immunomagnetic bead chain 21 is connected to the first inner side wall, one end of the second immunomagnetic bead chain 21 is connected to the second inner side wall, and the other end of the first immunomagnetic bead chain 21 and the other end of the second immunomagnetic bead chain 21 are arranged oppositely. The first immunomagnetic bead chain 21 and the second immunomagnetic bead chain 21 can capture bacteria at the same time, thereby increasing the capture area of ​​bacteria and ensuring the bacterial separation effect.

[0053] In some examples, the other end of the first immunomagnetic bead chain 21 abuts against the other end of the second immunomagnetic bead chain 21 to improve the capture effect of the bacteria in the separation channel 11 .

[0054] In some embodiments, there are multiple first immunomagnetic bead chains 21 , and there are multiple second immunomagnetic bead chains 21 . Multiple first immunomagnetic bead chains 21 are arranged side by side, and multiple second immunomagnetic bead chains 21 are arranged side by side.

[0055] It is understandable that a plurality of first immunomagnetic bead chains 21 are arranged side by side to form an immunomagnetic bead chain 21 group, and a plurality of second immunomagnetic bead chains 21 are arranged side by side to form an immunomagnetic bead chain 21 group, thereby effectively improving the capture effect of bacteria.

[0056] In some embodiments, at least two immunomagnetic bead chains 21 are evenly distributed along the circumference of the separation channel 11 , thereby forming a bacteria capture area along the inner wall surface of the separation channel 11 to achieve effective capture of bacteria in the separation channel 11 .

[0057] In some embodiments, the magnetic component 2 of the first immunomagnetic bead chain 21 also includes a ferromagnetic material 22 and a magnet 23. The ferromagnetic material 22 is arranged on the outer wall of the chip body 1, and the magnet 23 is connected to the side of the ferromagnetic material 22 facing away from the chip body 1. The ferromagnetic material 22 and the magnet 23 are used to construct a high-gradient magnetic field, and the immunomagnetic bead chain 21 is located in the high-gradient magnetic field.

[0058] It is understandable that the ferromagnetic material 22 and the magnet 23 are used to construct a high gradient magnetic field, so that the immunomagnetic bead chain 21 is in the high gradient magnetic field, and the immunomagnetic beads will form a chain in the high gradient magnetic field, ensuring the capture effect of bacteria in the shear fluid.

[0059] In some embodiments, the magnetic component 2 also includes a magnetic bead plate, which is attached to the inner wall of the separation channel 11 and extends along the length direction of the inner wall of the separation channel 11. The magnetic bead plate is detachably connected to the chip body 1.

[0060] It is understandable that the magnetic bead plate can capture bacteria in the shear fluid. During the flow of the sample, the magnetic bead plate and the immunomagnetic bead chain 21 can continuously capture bacteria, achieving double capture of bacteria and improving the bacterial separation effect.

[0061] In some examples, the magnetic bead plate extends along the length direction of the separation channel 11, and the shear fluid flows along the direction from the immunomagnetic bead chain 21 to the magnetic bead plate. That is, the immunomagnetic bead chain 21 will first capture the bacteria in the sample, and then the magnetic bead plate can perform a second capture of the bacteria in the sample to improve the bacterial separation effect.

[0062] The immunomagnetic bead chain 21 is arranged before the magnetic bead plate. Since the other end of the immunomagnetic bead chain 21 extends toward the center of the separation channel 11, the immunomagnetic bead chain 21 can capture bacteria that have not yet moved to the inner wall surface of the separation channel 11. With the flow of the shear fluid, when the bacteria flow to the corresponding position of the magnetic bead plate, the bacteria have basically moved to the inner wall surface of the separation channel 11, and the magnetic bead plate can effectively capture the bacteria.

[0063] In some embodiments, the first end of the chip body 1 of the first immunomagnetic bead chain 21 is formed with an inlet 12 connected to the separation channel 11, and the second end of the chip body 1 is formed with an outlet 13 connected to the separation channel 11, so as to facilitate the injection of shear fluid and sample into the separation channel 11, so that the shear fluid and sample can flow in the direction from the inlet 12 to the outlet 13.

[0064] In some embodiments, the bacteria separation chip further includes a first fluid pump connected to the inlet 12 to transport fluid into the separation channel 11 .

[0065] It can be understood that the shear fluid and the sample can be delivered to the separation channel 11 through the first fluid pump, and the shear fluid and the sample can flow in the separation channel 11 .

[0066] In some embodiments, the bacteria separation chip further includes a second fluid pump connected to the outlet 13 . The first fluid pump and the second fluid pump are used to drive the fluid in the separation channel 11 to flow back and forth.

[0067] It is understandable that the first fluid pump can drive the shear fluid and the sample in the separation channel 11 to flow from the inlet 12 to the outlet 13, and the second fluid pump can drive the shear fluid and the sample in the separation channel 11 to flow from the outlet 13 to the inlet 12. When the bacterial separation effect is insufficient, the shear fluid and the sample can be repeatedly flowed in the separation channel 11 by the first fluid pump and the second fluid pump to improve the bacterial separation effect.

[0068] According to the second aspect of the present application, refer to Figure 2 The present disclosure provides a method for isolating bacteria. The method for isolating bacteria comprises:

[0069] Step 101, injecting a shear fluid into the separation channel 11 of the chip body 1 to form a shear flow field in the separation channel 11;

[0070] Step 102, placing the immunomagnetic bead chain 21 on the inner wall of the separation channel 11, and constructing a high gradient magnetic field at the chip body 1, so that the immunomagnetic bead chain 21 is located in the high gradient magnetic field;

[0071] Step 103, mixing the sample to be separated with the separation particles 3 to obtain a mixed sample;

[0072] Step 104 : injecting the mixed sample into the separation channel 11 , so that the bacteria in the mixed sample flow toward the edge of the separation channel 11 under the action of the shear fluid and the separation particles 3 .

[0073] It is understandable that the separation channel 11 is a high-speed flow field filled with shear fluid. A high gradient magnetic field is constructed at the chip body 1, and the immunomagnetic bead chain 21 will form a chain in the high gradient magnetic field, so that the immunomagnetic bead chain 21 can capture bacteria.

[0074] The sample to be separated contains target bacteria. After the sample to be separated is mixed with the separation particles 3, it is continuously passed into the separation channel 11, and the flow rate is controlled. Under the action of the separation particles 3 and the shear fluid, the target bacteria gradually move toward the edges on both sides in the normal direction, so that the target bacteria flow toward the inner wall of the separation channel 11 in a directed manner, and are thus captured by the immunomagnetic bead chain 21, thereby achieving rapid separation of the target bacteria during the movement of the sample to be separated.

[0075] In some examples, the target bacteria are, for example, common Escherichia coli, Salmonella, and other bacteria with a diameter of 1-2 μm.

[0076] In some examples, a shear fluid is provided in the separation flow channel 11 to form a shear flow field. In order to simulate the shear flow field conditions in which platelets in the blood are easily adhered, the shear rate (γ) in the shear flow field is 20s -1 To 5000s -1 between.

[0077] Specifically, Q = 2πR4v max (1);

[0078] Where Q is the flow rate in the shear flow field, R is the radius of the shear flow field, and v max is the maximum flow velocity in the shear flow field;

[0079] The relationship between the maximum shear rate and the maximum flow rate is: γ = 2v max / R(2);

[0080] Substituting equation (2) into equation (1), we can obtain Q = 4πR5γ(3).

[0081] Taking a pipe with a radius of 5 mm as an example, Q = 0.007 ~ 1.97 mL / s = 0.47 ~ 118 mL / min.

[0082] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0083] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0084] The embodiments, implementation methods and related technical features of the present application can be combined and replaced with each other without conflict.

[0085] The above are only preferred embodiments of the present application and do not constitute any form of limitation to the present application. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. A bacterial separation chip, characterized in that: include: A chip body, wherein the chip body is formed with a separation flow channel, and the separation flow channel is used to accommodate a sample; A magnetic component connected to the chip body, at least part of which is located in the separation channel and on the inner wall surface of the separation channel, and is used to capture bacteria in the sample; Wherein, a shear fluid is provided in the separation channel, and separation particles are provided in the sample, so that the bacteria in the sample move toward the inner wall surface of the separation channel under the action of the shear fluid and the separation particles.

2. The bacterial separation chip according to claim 1, characterized in that: The shear fluid is a biocompatible liquid.

3. The bacterial separation chip according to claim 1, characterized in that: The separation particles are polystyrene microspheres.

4. The bacterial separation chip according to claim 1, characterized in that: The density of the separated particles is 1.05 g / cm 3 To 1.09g / cm 3 between; and / or, The concentration of the separated particles is 3.5×10 12 / L to 5.5×10 12 Between 1 / L; and / or, The size of the separated particles is between 6 μm and 8 μm.

5. The bacteria separation chip according to any one of claims 1 to 4, characterized in that: The magnetic component comprises an immunomagnetic bead chain, one end of the immunomagnetic bead chain is connected to the inner side wall of the separation channel, and the other end of the immunomagnetic bead chain extends toward the center of the separation channel.

6. The bacteria separation chip according to claim 5, characterized in that: The magnetic component includes at least two immunomagnetic bead chains, and the at least two immunomagnetic bead chains include a first immunomagnetic bead chain and a second immunomagnetic bead chain, and the first immunomagnetic bead chain and the second immunomagnetic bead chain are arranged opposite to each other.

7. The bacteria separation chip according to claim 6, characterized in that: The number of the first immunomagnetic bead chains is multiple, the number of the second immunomagnetic bead chains is multiple, the multiple first immunomagnetic bead chains are arranged side by side, and the multiple second immunomagnetic bead chains are arranged side by side.

8. The bacteria separation chip according to claim 5, characterized in that: The magnetic component also includes ferromagnetic material and a magnet. The ferromagnetic material is arranged on the outer wall of the chip body. The magnet is connected to the side of the ferromagnetic material facing away from the chip body. The ferromagnetic material and the magnet are used to construct a high-gradient magnetic field. The immunomagnetic bead chain is located in the high-gradient magnetic field.

9. The bacteria separation chip according to any one of claims 1 to 4, characterized in that: An inlet communicating with the separation channel is formed at the first end of the chip body, and an outlet communicating with the separation channel is formed at the second end of the chip body.

10. A bacteria separation method based on the bacteria separation chip according to any one of claims 1 to 9, characterized in that: include: Injecting a shear fluid into the separation flow channel of the chip body to form a shear flow field in the separation flow channel; Arranging the immunomagnetic bead chain on the inner side wall of the separation channel, and constructing a high gradient magnetic field at the chip body so that the immunomagnetic bead chain is located in the high gradient magnetic field; mixing the sample to be separated with the separation particles to obtain a mixed sample; The mixed sample is injected into the separation channel, so that the bacteria in the mixed sample flow toward the edge of the separation channel under the action of the shear fluid and the separation particles.

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