Droplet sorting system

Abstract

The utility model relates to the technical field of cell sorting, and discloses a liquid drop sorting system.The liquid drop sorting system comprises a flow channel assembly, a fluorescence signal detection device and a sorting device.The flow channel assembly defines a liquid drop flow channel allowing liquid drops to flow, a first liquid outlet flow channel and a second liquid outlet flow channel; the fluorescence signal detection device is used for exciting the liquid drops to emit fluorescence and marking the liquid drops meeting fluorescence conditions as target liquid drops; the sorting device is arranged corresponding to the liquid outlet section of the liquid drop flow channel, target liquid drops flowing through the liquid outlet section of the liquid drop flow channel enter the first liquid outlet flow channel under the deflection action of the sorting device, and non-target liquid drops enter the second liquid outlet flow channel.

Description

Technical Field

[0001] This application relates to the technical field of cell sorting, for example, to a droplet sorting system. Background Art

[0002] Antibodies are one of the important humoral immune mechanisms for the body to resist the invasion of pathogens such as viruses and bacteria. Protective vaccines are important weapons to contain the spread of various pathogens. They can not only specifically recognize pathogens, but also bind closely to antigens, thus effectively blocking the damage of pathogens to cells, tissues, and the body. Antibodies are produced by B cells and go through layers of screening in the lymphatic system. Only a very small number of B cells have gene rearrangements to produce high-affinity antibodies. How to effectively separate and enrich B cells that secrete high-affinity antibodies is a difficult point in the field of antibody research.

[0003] Related technologies disclose a system for detecting, sorting, and dispensing droplets for a bioassay, the system including: a microfluidic device including a first channel connected to a second channel and a waste channel through a first sorting junction; a plurality of water-in-oil droplets, wherein at least two of the plurality of water-in-oil droplets each include at least one cell, at least one particle, or at least one cell plus at least one particle; a first detector or sensor corresponding to a first detection point disposed along the first channel upstream of the sorting junction, wherein the first detector includes an optical detector; a second detector or sensor corresponding to a second detection point disposed along the second channel downstream of the sorting junction; a target droplet dispensing module including a dispensing nozzle disposed downstream of the second detection point; and a processor configured to index each of the plurality of target droplets dispensed by the dispensing nozzle using a first signal of the same target droplet detected by the first detector or sensor at the first detection point, a second signal of the same target droplet detected by the second detector or sensor at the second detection point, or both the first signal and the second signal.

[0004] In the process of implementing the embodiments of the present disclosure, it is found that at least the following problems exist in the related technologies:

[0005] In the related art, when a droplet flows through the first detection point or the second detection point, magnets, magnet pairs or magnet arrays are required to arrange the particulate matters in the droplet according to a certain rule so as to make its characteristics obvious. The magnetic particles in the droplet are magnetized near the monitoring point and arranged under the action of the magnetic field force. The particles in the droplet interact with the closer particles to form lines. When the magnets in the droplet are relatively dispersed, the particulate matters in the droplet are rearranged into multiple thin lines. When the magnets in the droplet are relatively dispersed, the particulate matters in the droplet are rearranged into multiple thin lines in the magnetic field. When the particulate matters in the droplet are arranged into multiple thin lines, when the droplet is subjected to fluorescence recognition, the characteristic peaks of the fluorescence signal are not obvious, which will affect the recognition accuracy of cells.

[0006] The related art also discloses a microfluidic chip device and a usage method thereof for sorting fluorescently labeled cells based on magnetic field control. The microfluidic chip includes a sample channel, two sheath fluid channels, a first fluorescence detection area, a second fluorescence detection area, a magnetic field control system, a magnetic field-controlled cell sorting area, a target cell channel, and a waste liquid channel. Among them, the sample channel is connected to the two sheath fluid channels, the sample channel and the two sheath fluid channels are connected in parallel to each other, and the sample channel is located between the two sheath fluid channels. The connecting pipes of the sample channel and the two sheath fluid channels are respectively a first flow channel and a second flow channel. The first flow channel and the second flow channel intersect with the two sheath fluid channels at a first intersection point and a second intersection point respectively. The target cell channel starts from the first intersection point, and the waste liquid channel starts from the second intersection point. The magnetic field-controlled cell sorting area is arranged on the first flow channel and the second flow channel. The cell sorting area includes a magnetic element. The magnetic element is controlled by the magnetic field control system to move back and forth on the first flow channel and the second flow channel to control the flow direction of the sample. When the magnetic element is located on the first flow channel, the sample channel is connected to the waste liquid channel. When the magnetic element is located on the second flow channel, the sample channel is connected to the target cell channel. The movement of the magnetic element enables the droplet to be controlled to flow to the waste liquid channel and the target cell channel.

[0007] In the process of implementing the embodiments of the present disclosure, it is found that at least the following problems exist in the related art:

[0008] In the related art, if antigens and secondary antibodies in a droplet are enriched by magnetic particles, when the droplet is near the magnetic element, the magnetic particles in the droplet will adhere to the magnetic element, affecting the sorting effect of cells. As a moving component in the flow channel, the magnetic element has a risk of squeezing and breaking cells during movement.

[0009] In addition, in the related art, a single set of electrode pairs is set to apply an electrophoretic force to the droplet to deflect the droplet. In this case, the droplet may be torn due to a large local force.

[0010] In addition, driving the droplet to deflect into the target flow channel only by electrophoresis force, electric field force or magnetic field force results in low throughput of cell sorting, and there is also a possibility of droplet breakage.

[0011] It should be noted that the information disclosed in the above background art section is only used to enhance the understanding of the background of the present application, and thus may include information that does not constitute the prior art known to those of ordinary skill in the art. Summary of the Invention

[0012] To provide a basic understanding of some aspects of the disclosed embodiments, a simple summary is given below. This summary is not a comprehensive review, nor is it intended to identify key / important elements or delineate the scope of protection of these embodiments, but rather serves as a prelude to the detailed description that follows.

[0013] Embodiments of the present disclosure provide a droplet sorting system to solve at least one problem existing in the related art.

[0014] In some embodiments, the droplet sorting system includes a flow channel assembly, a fluorescence signal detection device, and a sorting device. Among them, the flow channel assembly defines a droplet flow channel, a first liquid outlet flow channel, and a second liquid outlet flow channel for the droplet to flow through; the fluorescence signal detection device is used to excite the droplet to emit fluorescence and mark the droplet that meets the fluorescence condition as the target droplet; the sorting device is arranged corresponding to the liquid outlet section of the droplet flow channel, and the target droplet flowing through the liquid outlet section of the droplet flow channel deflects into the first liquid outlet flow channel under the deflection action of the sorting device, and the non-target droplet enters the second liquid outlet flow channel.

[0015] In some embodiments, the sorting device includes a sorting electromagnet, and the sorting electromagnet is arranged at the liquid outlet section of the droplet flow channel. The sorting electromagnet is activated when the target droplet flows through the liquid outlet section of the droplet flow channel so that the target droplet deflects to the first liquid outlet flow channel under the action of the magnetic field force.

[0016] In some embodiments, the sorting device includes a first air pump, and the first air pump is arranged in the first liquid outlet flow channel. The first air pump is configured to apply positive pressure to the first liquid outlet flow channel when the non-target droplet flows through the liquid outlet section of the droplet flow channel.

[0017] In some embodiments, the sorting device includes a second air pump, and the second air pump is arranged in the second liquid outlet flow channel. The second air pump is configured to apply positive pressure to the second liquid outlet flow channel when the target droplet flows through the sorting device.

[0018] In some embodiments, the sorting device further includes a positive electrode and a negative electrode. The positive electrode and the negative electrode are arranged on the same side of the droplet flow channel. When the positive electrode and the negative electrode are energized, an electric field acting on the liquid outlet section of the droplet flow channel is formed, and the target droplet deflects to the first liquid outlet flow channel under the action of the electrophoresis force.

[0019] In some embodiments, the sorting device further includes a positive electrode and a negative electrode. The positive electrode is disposed on one side where the first liquid outlet channel of the droplet flow channel is located; the negative electrode is disposed on one side where the first liquid outlet channel of the droplet flow channel is located. When the positive electrode and the negative electrode are energized, an electric field acting on the liquid outlet section of the droplet flow channel is formed, and the target droplet deflects to the first liquid outlet channel under the action of the electrophoresis force.

[0020] In some embodiments, the sorting device includes a plurality of positive electrodes and a plurality of negative electrodes. The plurality of positive electrodes and the plurality of negative electrodes are alternately arranged, and the plurality of negative electrodes are connected to each other.

[0021] In some embodiments, the sorting device includes a plurality of positive electrodes and two negative electrodes. The two negative electrodes are respectively located on both sides of the plurality of positive electrodes.

[0022] In some embodiments, the sorting device includes a plurality of positive electrodes, and the distances between the plurality of positive electrodes and the droplet flow channel are not completely the same.

[0023] In some embodiments, the sorting device includes an electrode assembly. The electrode assembly includes at least one electrode unit disposed on one side of the droplet flow channel. Wherein, the electrode unit includes one or more positive electrodes and two negative electrodes. The positive electrodes are arranged on the first side of the droplet flow channel; the two negative electrodes are arranged on the first side of the droplet flow channel, and the two negative electrodes are respectively located on both sides of the one or more positive electrodes.

[0024] In some embodiments, the electrode unit includes a plurality of positive electrodes, and two negative electrodes are respectively located on both sides of the plurality of positive electrodes.

[0025] In some embodiments, along the droplet flow direction, the distances between the plurality of positive electrodes and the droplet flow channel gradually increase.

[0026] In some embodiments, along the droplet flow direction, the voltages of the plurality of positive electrodes gradually decrease.

[0027] In some embodiments, the electrode assembly includes a plurality of electrode units, and the plurality of electrode units are arranged on the first side of the droplet flow channel.

[0028] In some embodiments, along the droplet flow direction, the distances between the plurality of electrode units and the droplet flow channel gradually increase.

[0029] In some embodiments, along the droplet flow direction, the voltages of the positive electrodes of the plurality of electrode units gradually decrease.

[0030] In some embodiments, two adjacent electrode units share a negative electrode.

[0031] In some embodiments, the electrode unit includes a positive electrode and two negative electrodes, and the positive and negative electrodes of the electrode assembly are arranged alternately.

[0032] In some embodiments, the positive and negative electrodes of the electrode assembly are arranged alternately at equal intervals.

[0033] In some embodiments, the negative electrodes of the electrode assembly are connected in communication, and the positive electrodes of the electrode assembly are independently controlled to conduct.

[0034] In some embodiments, the electrode assembly further includes a first shielding electrode, which is arranged on the second side of the droplet flow channel, and the first shielding electrode is opposite to the electrode unit.

[0035] In some embodiments, the first shielding electrode is connected in communication with the negative electrode of the electrode unit.

[0036] In some embodiments, the electrode assembly further includes a second shielding electrode, which is arranged on the first side of the droplet flow channel, and the second shielding electrode is arranged on the circumferential outer side of the electrode unit and surrounds the electrode unit.

[0037] In some embodiments, the second shielding electrode is connected in communication with the negative electrode of the electrode unit.

[0038] In some embodiments, the positive and negative electrodes of the electrode unit are connected to a power source through a high-voltage isolation pulse transformer.

[0039] In some embodiments, the sorting device includes the above-mentioned electrode assembly and a control device, wherein the control device is configured to control the plurality of positive electrodes of the electrode assembly to be energized one by one when the target droplet flows through the electrode assembly.

[0040] In some embodiments, the control device includes an acquisition module, a determination module, and a control module. The acquisition module is used to acquire the flow rate of the target droplet; the determination module is configured to determine the first moment when the target droplet flows through the working area of the electrode assembly according to the flow rate of the target droplet; the control module is configured to control the plurality of positive electrodes of the electrode assembly to be energized one by one starting from the first moment.

[0041] In some embodiments, the acquisition module includes a determination unit and a first calculation unit. The determination unit is configured to determine the first duration required for the droplet to flow through the fluorescence signal detection device according to the wave width of the fluorescence signal; the first calculation unit is configured to determine the flow rate of the droplet according to the first duration and the working length of the fluorescence signal detection device.

[0042] In some embodiments, the acquisition module includes a shooting control unit, a comparison unit, and a second calculation unit. Among them, the shooting control unit is configured to control the high-speed camera to continuously shoot droplet images at intervals of a second duration; the comparison unit is configured to compare the continuously shot droplet images to determine the displacement distance of the droplets; the second calculation unit is configured to determine the flow rate of the droplets according to the droplet displacement distance and the second duration.

[0043] In some embodiments, the control module includes a third calculation unit and a first execution unit. Among them, the third calculation unit is used to determine the power-on interval of the electrodes according to the flow rate of the target droplets; the first execution unit is configured to control the multiple electrodes of the electrode assembly to be powered on one by one starting from the first moment according to the power-on interval.

[0044] In some embodiments, the control module includes a fourth calculation unit and a second execution unit. Among them, the fourth calculation unit is used to determine the target voltage of the multiple electrodes according to the flow rate of the target droplets; the second execution unit is configured to control the multiple electrodes of the electrode assembly to be powered on one by one starting from the first moment according to the determined power-on voltage.

[0045] In some embodiments, the flow channel assembly further includes a microfluidic chip, and the microfluidic chip defines a positive electrode flow channel and a negative electrode flow channel. The positive electrode flow channel is filled with a conductive medium to form a positive electrode, and the negative electrode flow channel is filled with a conductive medium to form a negative electrode. The positive electrode includes the positive electrode, and the negative electrode includes the negative electrode.

[0046] In some embodiments, the material of the conductive medium is metal, and the metal conductive medium is filled into the positive electrode flow channel and / or the negative electrode flow channel in a liquid state.

[0047] In some embodiments, when the electrode assembly further includes a first shielding electrode, the microfluidic control chip further defines a first shielding electrode flow channel, and the first shielding electrode flow channel is filled with a conductive medium to form a first shielding electrode. The negative electrode flow channel is also communicated with the first shielding electrode flow channel.

[0048] In some embodiments, when the electrode assembly further includes a second shielding electrode, the microfluidic control chip further defines a second shielding electrode flow channel, and the second shielding electrode flow channel is filled with a conductive medium to form a second shielding electrode. The negative electrode flow channel is also communicated with the second shielding electrode flow channel.

[0049] In some embodiments, the microfluidic control chip further defines a connection flow channel. The first end of the connection flow channel is connected to the first shielding electrode flow channel, the second end of the connection flow channel is connected to the second shielding electrode flow channel, the second shielding electrode flow channel is directly communicated with the negative electrode flow channel, and the first shielding electrode flow channel is communicated with the negative electrode flow channel through the connection flow channel and the second shielding electrode flow channel.

[0050] In some embodiments, the flow channel assembly includes a microfluidic chip, and the microfluidic chip defines therein the droplet flow channel, the first liquid outlet flow channel, and the second liquid outlet flow channel.

[0051] In some embodiments, the microfluidic chip further defines a sheath liquid inlet flow channel and a sample liquid inlet flow channel. The liquid inlet end of the sample liquid inlet flow channel is used for filling droplets that have passed through a pre-magnetizing magnetic field. The liquid outlet end of the sample liquid inlet flow channel and the liquid outlet end of the sheath liquid inlet flow channel are in communication with the liquid inlet end of the droplet flow channel. The droplets that have passed through the pre-magnetizing magnetic field are mixed with the sheath liquid and then enter the droplet flow channel.

[0052] In some embodiments, the microfluidic chip further defines a positive electrode flow channel and a negative electrode flow channel. A conductive medium is filled in the positive electrode flow channel to form a positive electrode, and / or a conductive medium is filled in the negative electrode flow channel to form a negative electrode.

[0053] In some embodiments, the positive electrode flow channel is located on one side of the droplet flow channel, and the negative electrode flow channel is located on the other side of the droplet flow channel.

[0054] In some embodiments, the conductive medium is made of metal, and the metal conductive medium is filled into the electrode flow channel in a liquid state.

[0055] In some embodiments, the flow channel assembly further includes a support frame. The support frame includes a bottom plate, a first side plate, and a second side plate. The first side plate and the second side plate are oppositely arranged. Among them, the microfluidic chip is located between the first side plate and the second side plate and is lapped on the upward-facing surface of the bottom plate.

[0056] In some embodiments, the sorting device further includes an electrode mounting plate, a positive electrode connecting member, and a negative electrode connecting member. The electrode mounting plate is fixed to the first side plate and / or the second side plate of the support frame. The positive electrode connecting member is fixed to the electrode mounting plate and extends towards the microfluidic chip. The positive electrode connecting member is used to connect the positive electrode to a power source. The negative electrode connecting member is fixed to the electrode mounting plate and extends towards the microfluidic chip. The negative electrode connecting member is used to connect the negative electrode to a power source. In some embodiments, the fluorescence signal detection device includes a laser assembly and a fluorescence detection assembly. Among them, the laser assembly is used to emit a laser towards the magnetic particles drawn into a line shape, and the fluorescent marker in the droplet is excited by the laser to emit fluorescence. The fluorescence detection assembly is used to detect the fluorescence emitted by the fluorescent marker in the droplet.

[0057] In some embodiments, the laser assembly includes a first laser light source for emitting laser light of a first wavelength, and one of the antigen and the secondary antibody emits fluorescence of a first wavelength when excited by the laser light of the first wavelength; the fluorescence detection assembly includes: a first fluorescence detector for detecting fluorescence of the first wavelength.

[0058] In some embodiments, the laser assembly further includes a second laser light source, which is used to emit laser light of a second wavelength, and the other of the antigen and the secondary antibody emits fluorescence of a second wavelength when excited by the laser light of the second wavelength; the fluorescence detection assembly further includes: a second fluorescence detector, which is used to detect fluorescence of the second wavelength.

[0059] In some embodiments, the laser assembly further includes a coaxial system for guiding laser light of a first wavelength and laser light of a second wavelength to droplets in the droplet flow channel, and the coaxial system is further for guiding fluorescence of the first wavelength and fluorescence of the second wavelength in the droplet flow channel to a first fluorescence detector and a second fluorescence detector.

[0060] In some embodiments, the droplet sorting system also includes a fluorescent signal recognition device, which includes a light source component and an imaging component, wherein the light emission direction of the light source component is toward the droplets in the first magnetic field; and the imaging component, the imaging position is toward the droplets in the first magnetic field.

[0061] In some embodiments, the imaging assembly includes a high-speed camera, a lens of the high-speed camera faces the droplet in the first magnetic field, and a shutter of the high-speed camera opens synchronously with the light source assembly.

[0062] In some embodiments, the droplet sorting system further includes a fluorescence signal enhancement device, which is used to enhance the fluorescence signal of the magnetic particles in the droplets.

[0063] In some embodiments, the fluorescence signal enhancement device includes a magnet assembly for generating the first magnetic field, and the magnetic particles in the droplets are pulled into a linear shape in the first magnetic field.

[0064] In some embodiments, the fluorescence signal enhancement device further includes a pre-magnetization component, which is used to generate the pre-magnetization magnetic field. The magnetic particles in the droplets are magnetized and agglomerated in the pre-magnetization magnetic field, and the agglomerated magnetic particles are pulled into a linear shape in the first magnetic field.

[0065] In some embodiments, the pre-magnetization magnetic field has a magnetic field strength greater than a magnetic field strength of the first magnetic field.

[0066] In some embodiments, the pre-magnetization component includes a pre-magnetization pipeline and a pre-magnetization magnet, wherein the pre-magnetization pipeline defines a pre-magnetization flow channel for the flow of droplets; the pre-magnetization magnet is used to generate a pre-magnetization magnetic field, and at least a portion of the pre-magnetization flow channel is located in the pre-magnetization magnetic field.

[0067] In some embodiments, the pre-magnetized flow channel is connected to the droplet flow channel, and the droplet flow channel is located after the pre-magnetized flow channel along the droplet flow direction.

[0068] In some embodiments, the pre-magnetized magnet includes a first pre-magnetized magnet and a second pre-magnetized magnet, wherein the first pre-magnetized magnet is disposed on one side of the pre-magnetized pipeline; and the second pre-magnetized magnet is disposed on the other side of the pre-magnetized pipeline.

[0069] In some embodiments, the pre-magnetization magnet includes a pre-magnetization coil, which is wound around the pre-magnetization pipeline. The axis of the pre-magnetization coil is along the length direction of the pre-magnetization pipeline. When the coil is energized, the pre-magnetization magnetic field is generated.

[0070] In some embodiments, the pre-magnetized magnet is used to generate a pre-magnetized magnetic field with changing direction, and the magnetic particles in the droplets move and agglomerate under the action of the changing magnetic field force when in the pre-magnetized flow channel.

[0071] In some embodiments, the pre-magnetized magnet includes multiple magnet pairs, and the multiple magnet pairs are arranged near the pre-magnetized flow channel. Magnetic flux lines are formed between each magnet pair, and the directions of the magnetic flux lines of the multiple magnet pairs are different to form the pre-magnetized magnetic field with changing direction.

[0072] In some embodiments, the pre-magnetized magnet includes an electromagnet, and the pre-magnetized magnetic field with changing direction is formed by adjusting the current intensity and / or current direction of the electromagnet; or, the pre-magnetized magnet includes a coil, and the coil is wound around the pre-magnetized pipeline. When the coil is energized, the pre-magnetized magnetic field is generated, and the pre-magnetized magnetic field with changing direction is formed by adjusting the current intensity and / or current direction of the coil.

[0073] In some embodiments, the pre-magnetized flow channel is a direction-changing flow channel, at least a portion of which is located in the pre-magnetized magnetic field. When the magnetic particles in the droplets move in the direction-changing flow channel, they are affected by the force of the first magnetic field and move and agglomerate.

[0074] In some embodiments, the pre-magnetized flow channel includes a plurality of bent segments, and the plurality of bent segments are connected end to end to form a pre-magnetized flow channel with a changing direction.

[0075] In some embodiments, the pre-magnetized flow channel is a spiral flow channel.

[0076] In some embodiments, the pre-magnetized pipeline is wound around the pre-magnetized magnet to form the flow channel with a changing direction.

[0077] In some embodiments, the pre-magnetized magnetic field includes a first part and a second part. The magnetic field direction of the first part remains unchanged, and the magnetic field direction of the second part changes with time.

[0078] In some embodiments, the pre-magnetized magnet includes an alternating current electromagnet, and the second part of the pre-magnetized magnetic field is formed when the alternating current electromagnet is energized.

[0079] In some embodiments, the pre-magnetized magnet is a direct current electromagnet, and the first part of the pre-magnetized magnetic field is formed when the direct current electromagnet is energized.

[0080] In some embodiments, the pre-magnetized pipeline is a flexible hose, and the length of the part of the pre-magnetized flow channel located in the pre-magnetized magnetic field is adjusted by moving the pre-magnetized pipeline.

[0081] The droplet sorting system provided by the embodiments of the present disclosure can achieve the following technical effects:

[0082] The fluorescence signal detection device can accurately identify the target droplet. After the target droplet is identified, a deflection force is applied to the target droplet by the sorting device so that the target droplet can be deflected to the first liquid outlet channel. The sorting of droplets does not need to be carried out by setting moving parts on the path of droplet flow, reducing or avoiding the samples such as cells and bacteria in the droplets from being squeezed and broken by the moving parts.

[0083] Furthermore, by setting the pre-magnetization component, magnetic particles can be magnetized before entering the first magnetic field to form an aggregated state. After the magnetized and aggregated magnetic particles enter the first magnetic field, they can be pulled into a linear shape, so that the fluorescent substances in the particle group can be more fully excited by the laser, thereby improving the identification accuracy of droplets; a pressure difference is generated by the first air pump and / or the second air pump to drive the controlled movement of droplets, and no magnetic components are set on the path of droplet flow, so that the droplets will not adhere to the magnetic components when flowing.

[0084] The above general description and the following description are only exemplary and explanatory, and are not used to limit this application. Description of the Drawings

[0085] One or more embodiments are exemplarily illustrated by corresponding drawings. These exemplary illustrations and drawings do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are shown as similar elements. The drawings do not constitute a proportional limitation, and among them:

[0086] Figure 1 is a schematic structural diagram of a droplet sorting system provided by an embodiment of the present disclosure;

[0087] Figure 2 is a schematic structural diagram of another droplet sorting system provided by an embodiment of the present disclosure;

[0088] Figure 3 is a schematic structural diagram of another droplet sorting system provided by an embodiment of the present disclosure;

[0089] Figure 4 yes Figure 3 A magnified schematic diagram of point A in the middle;

[0090] Figure 5 Schematic diagram of the structure of a fluorescence signal enhancement device for a droplet sorting system provided by an embodiment of the present disclosure;

[0091] Figure 6 is a schematic structural diagram of a fluorescence signal enhancement device for another droplet sorting system provided by an embodiment of the present disclosure;

[0092] Figure 7 is a schematic structural diagram of a fluorescence signal enhancement device for another droplet sorting system provided by an embodiment of the present disclosure;

[0093] Figure 8 is a schematic structural diagram of a fluorescence signal enhancement device for another droplet sorting system provided by an embodiment of the present disclosure;

[0094] Figure 9 is the microstructure of the droplet that has not been pre-magnetized;

[0095] Figure 10 This is the microstructure of the droplet after pre-magnetization;

[0096] Figure 11 This is the microstructure of the droplet in the first magnetic field without pre-magnetization;

[0097] Figure 12 This is the microstructure of the pre-magnetized droplet in the first magnetic field;

[0098] Figure 13 is a graph of the fluorescence signal intensity of the droplet in the first magnetic field, wherein the left part is the fluorescence signal intensity when the droplet is not pre-magnetized, and the right part is the fluorescence signal intensity after the droplet is pre-magnetized;

[0099] Figure 14 is a schematic structural diagram of an electrode assembly provided by an embodiment of the present disclosure;

[0100] Figure 15 is a schematic structural diagram of another electrode assembly provided by an embodiment of the present disclosure;

[0101] Figure 16It is a schematic structural diagram of another electrode assembly provided by an embodiment of the present disclosure;

[0102] Figure 17 It is a schematic structural diagram of another electrode assembly provided by an embodiment of the present disclosure;

[0103] Figure 18 It is a schematic structural diagram of another electrode assembly provided by an embodiment of the present disclosure;

[0104] Figure 19 It is a schematic structural diagram of another electrode assembly provided by an embodiment of the present disclosure;

[0105] Figure 20 It is a schematic diagram of a droplet sorting method provided by an embodiment of the present disclosure;

[0106] Figure 21 It is a schematic diagram of another droplet sorting method provided by an embodiment of the present disclosure;

[0107] Figure 22 It is a schematic diagram of another droplet sorting method provided by an embodiment of the present disclosure;

[0108] Figure 23 It is a schematic diagram of another droplet sorting method provided by an embodiment of the present disclosure;

[0109] Figure 24 It is a schematic diagram of another droplet sorting method provided by an embodiment of the present disclosure;

[0110] Figure 25 It is a schematic diagram of a fluorescence signal detection method provided by an embodiment of the present disclosure;

[0111] Figure 26 It is a schematic diagram of a device for controlling a droplet sorting system provided by an embodiment of the present disclosure.

[0112] Reference numerals:

[0113] 100: Pre-magnetization assembly; 110: Pre-magnetization pipeline; 120: Pre-magnetization magnet; 121: First pre-magnetization magnet; 122: Second pre-magnetization magnet; 123: Pre-magnetization coil; 200: Magnet assembly; 210: First magnet; 220: Second magnet; 300: Flow channel assembly; 310: Microfluidic chip; 311: Droplet flow channel; 312: Sheath fluid inflow channel; 3121: Sheath fluid injection port; 313: Sample fluid inflow channel; 3131: Sample fluid injection port; 314: First liquid outlet channel; 3141: First liquid outlet; 315: Second liquid outlet channel; 3151: Second liquid outlet; 316: Positive electrode flow channel; 317: Negative electrode flow channel; 320: Support frame; 322: First side plate; 323: Second side plate; 410: First laser light source; 420: Second laser light source; 430: Coaxial system; 500: Fluorescence detection assembly; 510: First photomultiplier tube; 520: Second photomultiplier tube; 610: High-speed camera; 620: Light source assembly; 710: Carrier plate; 720: Fixing assembly; 721: First clamping member; 722: Second clamping member; 80: Electrode unit; 810: Positive electrode; 820: Negative electrode; 831: Positive electrode connecting piece; 832: Negative electrode connecting piece; 840: Electrode mounting plate; 850: First air pump; 860: Second air pump; 870: First shielding electrode; 880: Second shielding electrode; 900: Processor; 901: Memory; 902: Communication interface; 903: Bus. Detailed implementation manners

[0114] In order to be able to understand the features and technical content of the embodiments of the present disclosure in more detail, the implementation of the embodiments of the present disclosure will be elaborated in detail below with reference to the accompanying drawings. The attached drawings are only for reference and explanation purposes and are not used to limit the embodiments of the present disclosure. In the following technical descriptions, for the sake of explanation, multiple details are provided to provide a full understanding of the disclosed embodiments. However, one or more embodiments can still be implemented without these details. In other cases, well-known structures and devices can be shown in a simplified manner to simplify the drawings.

[0115] The terms "first", "second", etc. in the description, claims and above-mentioned drawings of the embodiments of the present disclosure are used to distinguish similar objects and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so as to implement the embodiments of the present disclosure described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion.

[0116] In the embodiments of the present disclosure, the terms "upper", "lower", "inside", "middle", "outside", "front", "back" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. These terms are mainly intended to better describe the embodiments of the present disclosure and their embodiments, and are not intended to limit the indicated devices, elements or components to having a specific direction, or to be constructed and operated in a specific direction. Moreover, in addition to being used to indicate directions or positional relationships, some of the above terms may also be used to indicate other meanings. For example, the term "upper" may also be used to indicate a certain dependency or connection relationship in certain circumstances. For those of ordinary skill in the art, the specific meanings of these terms in the embodiments of the present disclosure can be understood according to specific circumstances.

[0117] Furthermore, the terms "disposed," "connected," and "fixed" should be interpreted broadly. For example, "connected" can mean a fixed connection, a removable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection, an indirect connection through an intermediary, or an internal connection between two devices, elements, or components. Those skilled in the art will understand the specific meanings of these terms in the embodiments of this disclosure based on the specific circumstances.

[0118] Unless otherwise stated, the term "plurality" means two or more.

[0119] In the embodiment of the present disclosure, the character " / " indicates that the preceding and following objects are in an "or" relationship. For example, A / B means: A or B.

[0120] The term "and / or" describes an association between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or A and B.

[0121] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present disclosure can be combined with each other.

[0122] Antibodies are one of the body's key humoral immune mechanisms for defending against invasion by pathogens such as viruses and bacteria. Protective vaccines are a crucial weapon in curbing the spread of various pathogens. They not only specifically identify pathogens but also bind closely to antigens, effectively blocking damage to cells, tissues, and the body. Antibodies are produced by B cells and undergo multiple rounds of screening through the lymphatic system. Only a very small number of B cells undergo gene rearrangement to produce high-affinity antibodies. Effectively isolating and enriching B cells that secrete high-affinity antibodies is a challenge in antibody research.

[0123] Combine Figures 1 to 8As shown in the figure, an embodiment of the present disclosure provides a droplet sorting system. The droplet sorting system includes a flow channel assembly 300, a fluorescence signal detection device, and a sorting device. Among them, the flow channel assembly 300 defines a droplet flow channel 311, a first liquid outlet flow channel 314, and a second liquid outlet flow channel 315 for the flow of droplets; the fluorescence signal enhancement device is used to generate a pre-magnetization magnetic field and a first magnetic field, and the magnetic particles in the droplets are magnetized and aggregated in the pre-magnetization magnetic field, and the aggregated magnetic particles are pulled into a line in the first magnetic field; the fluorescence signal detection device is used to excite the droplets to emit fluorescence and mark the droplets that meet the fluorescence conditions as target droplets; the sorting device is arranged corresponding to the liquid outlet section of the droplet flow channel 311, and the target droplets flowing through the liquid outlet section of the droplet flow channel 311 enter the first liquid outlet flow channel 314 under the deflection action of the sorting device, and the non-target droplets enter the second liquid outlet flow channel 315.

[0124] Exemplarily, the droplet sorting system provided by the embodiment of the present disclosure can be used to sort biological samples such as cells, bacteria, and viruses. Each droplet contains at least one cell, bacterium, or virus, and a fluorescence-identifiable marker.

[0125] Taking one of the usage scenarios as an example, the droplet sorting system provided by the embodiment of the present disclosure is used to sort cells prepared into water-in-oil droplets. Each droplet contains at least one cell, multiple magnetic particles, multiple antibodies that specifically bind to the magnetic particles, multiple antigens and / or secondary antibodies that specifically bind to the antibodies, and at least one of the antigens and / or secondary antibodies is fluorescently stained.

[0126] The sample liquid sorted by the droplet sorting system includes multiple droplets. Each droplet contains at least one cell, multiple magnetic particles, multiple fluorescently labeled antigens, and fluorescently labeled secondary antibodies. After the antigen is recognized, the cell produces multiple antibodies, and the antigen can bind to multiple antibodies. The surface of the magnetic particles has multiple functional groups, which can bind to multiple antibodies secreted by the cells. The secondary antibody only binds to specific antibodies. If a target particle cluster in which the antigen, antibody, magnetic particle, and secondary antibody are all bound together appears in the droplet, it is considered that the cell in the droplet is a target cell that can produce high-affinity antibodies, and the droplet is a target droplet.

[0127] In order to confirm whether there is a target particle cluster in the droplet, the antigen and antibody in the target particle cluster can be fluorescently recognized. Exemplarily, a first laser and / or a second laser can be applied to the droplet. The fluorescent substance in the antigen can emit a first fluorescence under the excitation of the first laser, and the fluorescent substance in the secondary antibody can emit a second fluorescence under the excitation of the second laser. If the intensity and / or characteristic peak of the first fluorescence and / or the second fluorescence both meet the preset conditions, it is considered that the droplet is a target droplet.

[0128] The flow channel assembly is used to define a droplet flow channel 311, a first liquid outlet flow channel 314, and a second liquid outlet flow channel 315 for the flow of droplets. The liquid inlet ends of the first liquid outlet flow channel 314 and the second liquid outlet flow channel 315 are communicated with the liquid outlet end of the droplet flow channel 311. The fluorescence signal recognition of the droplets is completed in the droplet flow channel 311. After recognition, the target droplets flow out from the first liquid outlet flow channel 314, and the non-target droplets flow out from the second liquid outlet flow channel 315.

[0129] The sorting device provided by the embodiment of the present disclosure is located outside the droplet flow channel, and applies a deflection force to the droplets in a non-contact manner during the flow of the droplets. Exemplarily, the sorting device is one or more of a sorting electromagnet, an air pump, or a plurality of electrodes. The target droplets can be accurately identified by the fluorescence signal detection device. After the target droplets are identified, the sorting device applies a deflection force to the target droplets so that the target droplets can be deflected to the first liquid outlet flow channel. The sorting of the droplets does not need to be performed by setting moving components on the flow path of the droplets, so that the droplets will not contact the droplets and the samples in the droplets when being deflected, reducing or avoiding the samples in the droplets from being squeezed and broken by the moving components.

[0130] Optionally, the sorting device includes a sorting electromagnet, and the sorting electromagnet is arranged at the liquid outlet section of the droplet flow channel 311. The sorting electromagnet is activated when the target droplets flow through the liquid outlet section of the droplet flow channel 311, so that the target droplets are deflected to the first liquid outlet flow channel 314 under the action of the magnetic field force.

[0131] The sorting electromagnet corresponds to the liquid outlet section of the droplet flow channel 311 and is located on the side where the first liquid outlet flow channel 314 is located. When the target droplets flow through the liquid outlet section of the droplet flow channel 311, the sorting electromagnet is powered on. After the sorting electromagnet is powered on, it plays a traction role on the magnetic particles in the droplets, so that the target droplets are deflected to the first liquid outlet flow channel 314. By adopting such a setting form, the sorting of the target droplets can be conveniently realized. It should be noted that when the non-target droplets flow through the liquid outlet section of the droplet flow channel 311, the sorting electromagnet is not powered on, and the non-standard droplets flow to the second droplet flow channel 311 under the action of inertia.

[0132] The droplet sorting system drives the controlled movement of the droplets by magnetic force. There are no magnetic moving components set on the flow path of the droplets, and the droplets will not adhere to the magnetic components during the flow; the sorting of the droplets does not need to be performed by setting moving components on the flow path of the droplets, reducing or avoiding the samples such as cells, bacteria, and viruses in the droplets from being squeezed and broken by the moving components.

[0133] Optionally, the sorting device further includes a sorting electromagnet, and the sorting electromagnet is arranged at the liquid outlet section of the droplet flow channel 311. The sorting electromagnet is activated when the non-target droplets flow through the liquid outlet section of the droplet flow channel 311, so that the non-target droplets are deflected to the second liquid outlet flow channel 315 under the action of the magnetic field force.

[0134] In this case, when the target droplet flows through the liquid outlet end of the droplet flow channel 311, the sorting electromagnet is de-energized, and the target droplet flows towards the first liquid outlet flow channel 314 under the action of inertia.

[0135] With such a setting form, only non-target droplets will be affected by the magnetic force of the sorting electromagnet when flowing through the liquid outlet section of the droplet flow channel, while the target droplets will not be affected by the magnetic force of the sorting electromagnet when flowing through the liquid outlet section of the droplet flow channel. The magnetic particles in the target droplets will not be affected by the magnetic force of the sorting electromagnet, which can reduce or avoid the damage to samples such as cells, bacteria, and viruses in the droplets when the magnetic particles move under the action of the magnetic field force.

[0136] Optionally, as shown in Figure 5 the sorting device includes a first air pump 850. The first air pump 850 is arranged in the first liquid outlet flow channel 314 and is configured to apply positive pressure to the first liquid outlet flow channel 314 when non-target droplets flow through the liquid outlet section of the droplet flow channel 311.

[0137] When the first air pump 850 operates, it applies positive pressure to the first liquid outlet flow channel 314. In this way, a certain pressure difference is generated between the first liquid outlet flow channel 314 and the second liquid outlet flow channel 315, and non-target droplets tend to the second liquid outlet flow channel 315 under the action of the pressure difference when flowing through the liquid outlet section of the droplet flow channel 311. The response speed of the air pump is relatively fast, and high-speed sorting of droplets can be achieved. In addition, when positive pressure is applied to the first liquid outlet flow channel 314 by the air pump, the force on the droplets is uniform, and the samples in the droplets are not easily damaged.

[0138] It should be noted that the shape of the flow channel can be designed so that the target droplets and non-target droplets enter the first liquid outlet flow channel 314 when the first air pump 850 is not operating. In this way, only by starting and stopping the first air pump 850 can the target droplets enter the first liquid outlet flow channel 314 and the non-target droplets enter the second liquid outlet flow channel 315. For the shape of the flow channel, exemplarily, the liquid inlet section of the first liquid outlet flow channel 314 is located on the extension line of the liquid outlet section of the droplet flow channel 311, and the liquid inlet section of the second liquid outlet flow channel 315 forms an angle less than or equal to 150° with the liquid outlet end of the droplet flow channel 311.

[0139] When using the droplet sorting system provided by the embodiments of the present disclosure, the pressure difference generated by the first air pump is used to drive the controlled movement of the droplets. There are no magnetic components arranged in the path of droplet flow, and the droplets will not adhere to the magnetic components when flowing; the sorting of droplets does not need to be carried out by arranging moving components in the path of droplet flow, which reduces or avoids the samples in the droplets from being squeezed and broken by the moving components.

[0140] Optionally, as shown in Figure 5As shown, the sorting device includes a second air pump 860. The second air pump 860 is disposed in the second liquid outlet channel 315, and the second air pump 860 is configured to apply a positive pressure to the second liquid outlet channel 315 when the target droplet flows through the sorting device.

[0141] When the second air pump 860 operates, it applies a positive pressure to the second liquid outlet channel 315. In this way, a certain pressure difference is generated between the first liquid outlet channel 314 and the second liquid outlet channel 315. When the target droplet flows through the liquid outlet section of the droplet channel 311, it deflects towards the first liquid outlet channel 314 under the action of the pressure difference. In this way, high-speed sorting of the droplets can also be achieved, and the target droplet in the target droplet is not easily damaged when the target droplet deflects.

[0142] It should be noted that the shape of the flow channel can be designed so that the target droplet and the non-target droplet enter the second liquid outlet channel 315 when the second air pump 860 does not operate. In this way, only by starting and stopping the second air pump 860 can the target droplet enter the first liquid outlet channel 314 and the non-target droplet enter the second liquid outlet channel. For the shape of the flow channel, exemplarily, the liquid inlet section of the second liquid outlet channel 315 is located on the extension line of the liquid outlet section of the droplet channel 311, and the liquid inlet section of the first liquid outlet channel 314 forms an angle less than or equal to 150° with the liquid outlet end of the droplet channel 311.

[0143] In addition, the sorting device can be provided with the above-mentioned first air pump 850 and second air pump 860 at the same time. When the sorting device includes the first air pump 850 and the second air pump 860, the target droplet enters the first liquid outlet channel 314 under the action of the pressure difference, and the non-target droplet enters the second liquid outlet channel 315 under the action of the pressure difference. In this way, the sorting of the droplets can be better completed.

[0144] Optionally, as shown in Figure 8 the sorting device includes a positive electrode 810 and a negative electrode 820. The positive electrode 810 and the negative electrode 820 are disposed on the same side of the droplet channel. When the positive electrode 810 and the negative electrode 820 are energized, an electric field acting on the liquid outlet section of the droplet channel 311 is formed, and the target droplet deflects to the first liquid outlet channel 314 under the action of the electrophoresis force.

[0145] The length direction of the droplet channel is the flow direction of the droplet, and this direction is used as the axis of the droplet channel. Taking the length direction of the droplet channel as the dividing line, the droplet channel divides the plane where it is located into two regions, one region is one side, and the other region is the second side. The first liquid outlet channel is located in the first region, and the positive electrode and the negative electrode are also located in the first region. The first liquid outlet channel, the positive electrode and the negative electrode are located on the same side of the droplet channel.

[0146] The droplet flows along the droplet flow under the drive of an external force, flowing from the liquid inlet end of the droplet flow channel to the liquid outlet section of the droplet flow channel. When the droplet flows to the liquid outlet section of the droplet flow channel, it enters the action range of the electrode assembly. When the electrode assembly is energized, an electric field is formed, and the droplet deflects towards the side close to the positive electrode 810 and the negative electrode 820 under the action of the electric field force. When the droplet continues to flow under the action of the external force, since it is closer to the side where the first liquid outlet flow channel is located, it is easier to enter the first liquid outlet flow channel. In this process, it can be considered that the target droplet deflects under the action of the electrophoresis force, so that it can enter the first liquid outlet flow channel.

[0147] Optionally, as Figure 18 shown, the sorting device includes a plurality of positive electrodes 810 and a plurality of negative electrodes 820. The plurality of positive electrodes 810 and the plurality of negative electrodes 820 are alternately arranged, and the plurality of negative electrodes 820 are connected.

[0148] The plurality of positive electrodes and the plurality of negative electrodes are alternately arranged, and an electric field is formed between two adjacent positive electrodes and negative electrodes. For a droplet, the successive energization of the plurality of positive electrodes can pull the droplet towards the side where the positive electrode or the negative electrode is located. With such an arrangement form, the droplet can be pulled multiple times by the plurality of positive electrodes and the plurality of negative electrodes, so that the target droplet deflects to the first liquid outlet flow channel. This can reduce or avoid the droplet being broken due to excessive electrophoresis force. In addition, the form of pulling by the plurality of positive electrodes and the plurality of negative electrodes can improve the throughput of droplet sorting.

[0149] It should be noted that the positive electrode and the negative electrode can be connected to alternating current. In the case of connecting to alternating current, the alternating electric field between the positive and negative electrodes can also generate an electrophoresis force to deflect the droplet. In this case, the positive electrode and the negative electrode are only used to distinguish the opposite electrodes, and it is not specified that the positive electrode can only be connected to direct current positive electricity or the negative electrode can only be connected to direct current negative electricity.

[0150] By only controlling the on-off of the plurality of positive electrodes alone, the electrophoresis force can be applied to the droplet multiple times in sequence to deflect the droplet. The form in which the plurality of negative electrodes are connected can reduce the difficulty of setting the negative electrodes.

[0151] Optionally, the sorting device includes a plurality of positive electrodes and two negative electrodes, and the two negative electrodes are located on both sides of the plurality of positive electrodes.

[0152] When any one of the plurality of positive electrodes is energized, an electric field is formed between it and the two negative electrodes. When the distances between the positive electrode and the two negative electrodes are different, the target droplet deflects towards the first liquid outlet flow channel under the action of the electrophoresis force. The form of the plurality of positive electrodes cooperating with the two negative electrodes can reduce the number of negative electrodes, thereby reducing the difficulty of arranging the negative electrodes.

[0153] Optionally, the sorting device includes a plurality of positive electrodes 810, and the distances between the plurality of positive electrodes 810 and the droplet flow channel 311 are not completely the same.

[0154] The sorting device includes a plurality of positive electrodes 810, which can form an electric field with a certain gradient. The droplets tend to move in the direction of the electric field gradient in the electric field, so as to better deflect towards the corresponding flow channels.

[0155] Optionally, when the target droplets flow through the liquid outlet section of the droplet flow channel, the plurality of positive electrodes are activated successively.

[0156] If the droplets are simultaneously subjected to the electrophoretic forces of multiple electric fields, it will lead to unclear movement intentions of the droplets. The multiple positive electrodes are activated successively, and the target droplets are deflected by only one electric field within a period of time. Adopting such a setting form is beneficial for the sorting device to deflect the target droplets to the first liquid outlet flow channel.

[0157] Optionally, in combination with FIG. Figure 14 、 Figure 15 、 Figures 17 to 19 As shown, the sorting device includes an electrode assembly. The electrode assembly includes at least one electrode unit arranged on one side of the droplet flow channel 311. Among them, the electrode unit includes one or more positive electrodes 810 and two negative electrodes 820. The positive electrodes 810 are arranged on the first side of the droplet flow channel 311; the two negative electrodes 820 are arranged on the first side of the droplet flow channel 311, and the two negative electrodes 820 are respectively located on both sides of one or more positive electrodes 810.

[0158] The droplet sorting system has the function of identifying target droplets, and the electrode assembly is used to drive the target droplets to move towards the target side. At the electrode assembly, when the electrodes are energized, the surface tension of the droplets will be affected by the surface charge, and the change of the surface tension will cause the shape of the droplets to change. When the shape of the droplets changes, they move directionally in the droplet flow channel, that is, move towards the side where the electrode assembly is located. This movement of the droplets under the action of the electric field can also be considered as the movement of the droplets under the action of the electrophoretic force.

[0159] It should be noted that the positive electrodes and negative electrodes can be connected to alternating current. In the case of connecting alternating current, the alternating electric field between the positive and negative electrodes can also generate an electrophoretic force to deflect the droplets. In this case, the positive electrodes and negative electrodes are only used to distinguish opposite electrodes, and it is not limited that the positive electrodes can only be connected to direct current positive electricity or the negative electrodes can only be connected to direct current negative electricity.

[0160] Specifically, the sorting device includes a sheath liquid inflow channel 312, a sample liquid inflow channel 313, a droplet flow channel 311, a first liquid outlet flow channel 314, and a second liquid outlet flow channel 315.

[0161] The sheath liquid inflow channel 312 is used to fill the sheath liquid, and a sheath liquid injection port 3121 is provided in the sheath liquid inflow channel. The sheath liquid is a liquid medium used to focus water-in-oil droplets or samples. After the water-in-oil droplets or samples are squeezed by the sheath liquid, a stable liquid flow environment is formed together with the sheath liquid, so that the water-in-oil droplets or samples can pass through the droplet flow channel in a single column form and substantially along the central axis of the droplet flow channel. Exemplarily, the sheath liquid is an oil phase. The liquid inlet end of the sample liquid inflow channel 313 is used to fill the sample liquid, and a sample liquid injection port 3131 is provided in the sample liquid injection channel. The sample liquid contains water-in-oil droplets, and the droplets at least include fluorescently identifiable markers. Exemplarily, the droplet sorting system provided by the embodiments of the present disclosure can be used to sort biological samples such as cells, bacteria, and viruses. The droplets at least include one cell, bacterium or virus, and a fluorescently identifiable marker.

[0162] Exemplarily, the identification markers include a plurality of magnetic particles, a plurality of fluorescently labeled antigens, and a fluorescently labeled secondary antibody. After the antigen is recognized, the cell produces a variety of antibodies, and the antigen can bind to a variety of antibodies. The surface of the magnetic particle has a plurality of functional groups, which can bind to a variety of antibodies secreted by the cell. The secondary antibody only binds to a specific antibody. If a target particle group in which the antigen, antibody, magnetic particle, and secondary antibody are all bound together appears in the droplet, the cell in the droplet is considered to be a target cell that can produce high-affinity antibodies, and the droplet is a target droplet.

[0163] The water-in-oil droplets in the sample liquid are used to isolate adjacent droplets. The water-in-oil droplets are further mixed with the sheath liquid in the sheath liquid inflow channel, and thus flow in the droplet flow channel 311 at a preset flow rate and a preset adjacent distance.

[0164] This is beneficial for the droplet sorting system to identify, observe, and sort the droplets in the sample liquid.

[0165] During the process of pulling the target droplet to the target side of the droplet flow channel, if the acting force is small and the acting time is short, the target droplet is not easily deflected. If the acting force is large, the droplet is easily broken, causing sample damage. The electrode assembly provided by the embodiments of the present disclosure includes at least one electrode unit. The electrode unit includes at least one or more positive electrodes and two negative electrodes, and the two negative electrodes are located on both sides of the one or more positive electrodes.

[0166] One or more positive electrodes of the electrode unit and the two negative electrodes respectively form an electric field acting on the target droplet. When the target droplet flows through the electrode assembly, it is subjected to a uniform and continuous pulling force, and then deflects to the target side of the droplet flow channel. Since the electric field formed by the positive electrode and the two negative electrodes has a large acting range, the droplets in the target droplet are not easily broken. The acting time of the electric field formed by the electrode unit is long, and the target droplet is easily deflected to the target side.

[0167] When the electrode unit includes a positive electrode, the positive electrode and the two negative electrodes form two electric fields. The two electric fields are located on both sides of the positive electrode, making it difficult for electric field superposition or electric field interference to occur.

[0168] Using the electrode assembly provided in the embodiment of the present disclosure, the electrode unit can provide continuous and uniform pulling force for the target droplets, thereby allowing the droplets to pass through the droplet flow channel at a higher speed, which can significantly improve the flux of droplet sorting; the pulling force is provided to the target droplets by the multiple electric fields of the electrode unit, and the pulling force on the target droplets is relatively gentle, and the droplets are not easily broken.

[0169] Optionally, combined Figure 14 、 Figure 15 As shown, the electrode unit includes a plurality of positive electrodes, and two negative electrodes are respectively located on both sides of the plurality of positive electrodes.

[0170] When the electrode unit includes multiple positive electrodes, the multiple positive electrodes form multiple electric fields with the two negative electrodes respectively. When the target droplet flows through the electrode assembly, the electrophoretic force it is subjected to first gradually increases and then gradually decreases, and the target droplet is deflected more fully in the droplet flow channel.

[0171] Optionally, along the flow direction of the liquid droplets, the distances between the plurality of positive electrodes and the liquid droplet flow channel gradually increase.

[0172] When a target droplet flows through the electrode unit, it deflects toward the first side of the droplet flow channel under the action of the deflection force applied by the electrode assembly. The target droplet gradually decreases in distance from the multiple positive electrodes, and the electric field force it experiences gradually increases. The gradually increasing distance between the multiple positive electrodes and the droplet flow channel ensures that the target droplet is subjected to uniform force as it flows through the electrode assembly. Furthermore, using this arrangement, the multiple positive electrodes can be supplied with substantially equal voltages, which facilitates voltage control of the multiple positive electrodes.

[0173] Optionally, along the flow direction of the droplet, the voltages of the plurality of positive electrodes gradually decrease.

[0174] This arrangement allows the force applied to the target droplet to remain essentially constant as it flows through the electrode assembly, thereby reducing the risk of the droplet being broken. Furthermore, by gradually decreasing the voltage across the multiple positive electrodes, the multiple positive and negative electrodes of the electrode assembly can be placed as close as possible to the droplet flow path, facilitating the placement of multiple positive and negative electrodes.

[0175] Optionally, combined Figure 15 As shown, the electrode assembly includes a plurality of electrode units 80, and the plurality of electrode units 80 are arranged on a first side of the droplet flow channel.

[0176] The electrode assembly includes multiple electrode units, which can further increase the range of action of the electric field formed by the electrode assembly. When the droplet flow rate is constant, the time the target droplet flows in the liquid outlet section of the droplet flow channel increases, thereby increasing the time the target droplet is affected by the electric field force of the electrode assembly. This allows the electrode assembly to pass a lower voltage, thereby reducing the electromagnetic signal interference of the electrode assembly to the droplet sorting system and reducing the risk of electrode breakdown. When the voltage of the electrode assembly is constant, the droplets can be allowed to pass through at a higher flow rate, which can increase the number of droplets sorted per unit time, that is, improve the sorting flux of the droplet sorting system.

[0177] Optionally, along the flow direction of the droplet, the distance between the plurality of electrode units and the droplet flow channel gradually increases.

[0178] When a target droplet flows through an electrode unit, it is deflected toward the first side of the droplet flow channel by the deflection force applied by the electrode assembly. The target droplet gradually decreases in distance from the electrode unit, and the electric field force it experiences gradually increases. By gradually increasing the distance between multiple electrode units and the droplet flow channel, the target droplet is subjected to uniform force as it flows through the electrode assembly. Furthermore, using this arrangement, the multiple electrode units can be supplied with substantially equal voltages, facilitating voltage control across the multiple electrode units.

[0179] Optionally, along the flow direction of the droplet, the voltage of the positive electrodes of the plurality of electrode units gradually decreases.

[0180] This ensures that the force applied to the target droplets remains essentially constant as they flow through the electrode assembly, reducing the risk of the droplets being broken. Furthermore, by gradually decreasing the voltages of the multiple positive electrodes, the multiple positive and negative electrodes of the electrode assembly can be placed as close to the droplet flow path as possible, facilitating the placement of multiple positive and negative electrodes.

[0181] Optionally, combined Figure 16 As shown, two adjacent electrode units 80 share a negative electrode 820 .

[0182] Two adjacent electrode units share a negative electrode, which reduces the number of negative electrodes and thus the cost of the electrode assembly. It also ensures that the electrophoretic force exerted on the target droplets at the electrode assembly is consistent and uniform. This improves the success rate of deflecting the target droplets and increases the throughput of the droplet sorting system.

[0183] Optionally, combined Figure 17 、 Figure 18 As shown, the electrode unit includes a positive electrode and two negative electrodes, and the positive electrodes and negative electrodes of the electrode assembly are alternately arranged.

[0184] As an implementation, each electrode unit includes a positive electrode and two negative electrodes. Two adjacent electrode units share a negative electrode, and the electrodes of the electrode assembly are arranged in an alternating pattern of positive and negative electrodes. With such an arrangement, the multiple electric fields formed by the multiple positive electrodes and multiple negative electrodes in the electrode assembly are relatively uniform, and it is not easy for two adjacent electric fields to be superimposed.

[0185] With such an arrangement, when a single positive electrode operates, the electrophoretic force acting on the droplet jointly with the two adjacent negative electrodes is relatively uniform, and the droplet is not easily broken when driving the droplet to move.

[0186] Optionally, as shown in Figures 17 to 19 the negative electrodes 820 of the electrode assembly are connected in communication, and the positive electrodes 810 of the electrode assembly are independently controlled to conduct.

[0187] There is a potential difference between the positive electrode and the negative electrode, thus forming an electric field acting on the target droplet. The multiple negative electrodes are connected in communication, and by supplying power to the positive electrode, an electric field is formed between the positive electrode and the negative electrode, which can simplify the wiring of the multiple negative electrodes. In addition, when the multiple negative electrodes are connected in communication, the electric potentials are equal, which is beneficial to adjusting the electric field strength by adjusting the voltage of the positive electrode.

[0188] The multiple positive electrodes are independently controlled to conduct. Either multiple positive electrodes can be energized simultaneously or multiple positive electrodes can be energized one by one. Such an arrangement is beneficial for the electrode assembly to achieve multiple different sorting methods.

[0189] Optionally, as shown in Figure 17 and Figure 19 the electrode assembly further includes a first shielding electrode 870. The first shielding electrode 870 is arranged on the second side of the droplet flow channel 311, and the first shielding electrode 870 is opposite to the electrode unit 80.

[0190] With the first shielding electrode provided, the electromagnetic action generated by the positive electrode towards the second side of the first flow channel is limited within the first shielding electrode. This can reduce the electromagnetic interference caused by the electric field between the positive electrode and the negative electrode to the electronic components of the droplet sorting system.

[0191] Optionally, the first shielding electrode 870 is connected in communication with the negative electrode 820 of the electrode unit.

[0192] In this case, the negative electrode of the electrode unit is the grounding electrode, and the first shielding electrode is also the grounding electrode. This can simplify the wiring of the negative electrode and the first shielding electrode of the electrode assembly, thereby reducing the cost of the electrode assembly.

[0193] Optionally, as shown in Figure 17As shown, the electrode assembly further includes a second shielding electrode 880. The second shielding electrode 880 is disposed on the first side of the droplet flow channel, and is disposed on the circumferential outer side of the electrode unit and surrounds the electrode unit.

[0194] With the second shielding electrode provided, the electromagnetic effect generated by the positive electrode towards the first side of the first flow channel is limited within the second shielding electrode. This can further reduce the electromagnetic interference caused by the electric field between the positive electrode and the negative electrode to the electronic components of the droplet sorting system.

[0195] Optionally, the second shielding electrode 880 is connected to the negative electrode 820 of the electrode unit.

[0196] In this case, the negative electrode of the electrode unit is the grounding electrode, and the second shielding electrode is also the grounding electrode. This can simplify the wiring of the negative electrode and the second shielding electrode of the electrode assembly, thereby reducing the cost of the electrode assembly.

[0197] Optionally, the positive electrode and / or the negative electrode of the electrode unit are connected to the power supply through a high-voltage isolation pulse transformer.

[0198] There is a high electrical isolation between the primary side and the secondary side of the high-voltage isolation pulse transformer, which can ensure the safety of the equipment and personnel; the transformer can transmit pulse signals and has good pulse response characteristics. Adopting such a setting form is beneficial to improving the safety of the droplet sorting system.

[0199] If multiple positive electrodes are all energized, when the target droplet flows through the electrode assembly, it is affected by multiple electric fields, and the force on the target droplet is complex and the droplet is easily broken. The control device controls the multiple positive electrodes to be energized one by one. The target droplet is only affected by one or two electric fields within the same time period, the deflection of the target droplet is easy to control, and the droplet is not easily broken.

[0200] Using the sorting device provided by the embodiments of the present disclosure, the electrode assembly of the electrode assembly can provide a continuous and uniform pulling force for the target droplet, thereby allowing the droplet to pass through the droplet flow channel at a higher speed, which can significantly improve the sorting throughput; by providing a pulling force for the target droplet through multiple electrode units or multiple positive electrodes of the electrode assembly, the pulling force received by the target droplet is relatively gentle, and the droplet is not easily broken.

[0201] Optional, in combination with Figure 2 、 Figures 5 to 8 、 Figures 14 to 19 As shown, the flow channel assembly includes a microfluidic chip 310. The microfluidic chip defines a droplet flow channel 311, a first liquid outlet flow channel 314, and a second liquid outlet flow channel 315 inside it.

[0202] The use of a microfluidic chip can achieve high-throughput droplet sorting, thereby improving the efficiency of experimental research. The microfluidic chip has a low cost, is easy to use and carry, and can reduce the experimental cost. The microfluidic chip technology can also achieve non-destructive sorting of droplets, ensuring the activity and integrity of the samples.

[0203] Optionally, in combination with Figures 17 to 19 As shown, the microfluidic chip further defines a sheath liquid inlet channel 312 and a sample liquid inlet channel 313. The liquid inlet end of the sample liquid inlet channel 313 is used to fill droplets that have passed through a pre-magnetization magnetic field. The liquid outlet end of the sample liquid inlet channel 313 and the liquid outlet end of the sheath liquid inlet channel 312 are connected to the liquid inlet end of the droplet channel 311. The droplets that have passed through the pre-magnetization magnetic field are mixed with the sheath liquid and then enter the droplet channel 311.

[0204] The pre-magnetized droplets are water-in-oil droplets wrapped by the sheath liquid. However, the water-in-oil droplets are used to isolate the mutual interference of antibodies and antigens between adjacent droplets. After the water-in-oil droplets enter the sample liquid inlet channel 313 of the microfluidic chip 310, they are mixed with the sheath liquid in the sheath liquid inlet channel 312 again, so that the droplets can flow in the droplet channel 311 at a preset flow rate and a preset adjacent distance. With such a setting form, it is beneficial to identify, observe, and sort the droplets in the microfluidic chip 310.

[0205] Optionally, in combination with Figure 14 、 Figure 15 、 Figures 17 to 19 As shown, the microfluidic chip defines a positive electrode channel 316 and a negative electrode channel 317. The positive electrode channel 316 is filled with a conductive medium to form a positive electrode, and the negative electrode channel 317 is filled with a conductive medium to form a negative electrode.

[0206] The use of a microfluidic chip can achieve high-throughput droplet sorting, thereby improving the efficiency of experimental research. The microfluidic chip has a low cost, is easy to use and carry, and can reduce the experimental cost. The microfluidic chip technology can also achieve non-destructive sorting of droplets, ensuring the activity and integrity of the samples.

[0207] The microfluidic chip further defines a plurality of positive electrode channels 316 and a plurality of negative electrode channels 317. The positive electrode and the negative electrode of the microfluidic chip are located inside the microfluidic chip, which can better drive the droplets to deflect in the plane where the microfluidic chip is located. In addition, the positive electrode and the negative electrode are in the form of being embedded in the microfluidic chip, reducing the risk of electrode short circuit or leakage in the droplet sorting system.

[0208] Optionally, the material of the conductive medium is metal, and the metal conductive medium is filled into the positive electrode channel and / or the negative electrode channel in a liquid state.

[0209] Adopting such a configuration reduces the difficulty of processing and forming the positive electrode and the negative electrode, and reduces the cost of the droplet sorting system.

[0210] Optionally, combined Figure 17 As shown, when the electrode assembly further includes a first shielding electrode, the microfluidic control chip further defines a first shielding electrode flow channel 318, which is filled with a conductive medium to form the first shielding electrode, and the negative electrode flow channel is also connected to the first shielding electrode flow channel.

[0211] In this way, the first shielding electrode can be integrated into the microfluidic chip, which simplifies the structure of the sorting device and reduces the cost of the sorting device.

[0212] Optionally, combined Figure 17 As shown, when the electrode assembly further includes a second shielding electrode, the microfluidic control chip further defines a second shielding electrode flow channel 319, which is filled with a conductive medium to form a second shielding electrode, and the negative electrode flow channel is also connected to the second shielding electrode flow channel.

[0213] In this way, the second shielding electrodes can be integrated into the microfluidic chip, which simplifies the structure of the sorting device and reduces the cost of the sorting device.

[0214] Optionally, combined Figure 19 As shown, the microfluidic control chip also defines a connecting channel 3189, a first end of the connecting channel 3189 is connected to the first shielding electrode channel 318, a second end of the connecting channel is connected to the second shielding electrode channel 319, the second shielding electrode channel is directly connected to the negative electrode channel, and the first shielding electrode channel is connected to the negative electrode channel through the connecting channel.

[0215] With this arrangement, multiple negative electrodes, first shielding electrodes, and second shielding electrodes can be connected through only one electrode connector, which simplifies the connection structure of the negative electrodes, first shielding electrodes, and second shielding electrodes and reduces the cost of the sorting device.

[0216] Optionally, the microfluidic control chip further defines a droplet flow channel 311 for droplet flow, a first liquid outlet flow channel 314 and a second liquid outlet flow channel 315, wherein the electrode assembly is arranged on the first side of the liquid outlet end of the droplet flow channel 311, and when the target droplet flows through the liquid outlet section of the droplet flow channel 311, the electrode assembly is activated to deflect the target droplet to the first liquid outlet flow channel 314, and when the non-target droplet flows through the liquid outlet section of the droplet flow channel 311, the electrode assembly is not activated, and the non-target droplet enters the second liquid outlet flow channel 315.

[0217] The positive electrode flow channel 316, the negative electrode flow channel 317, the droplet flow channel 311, the first liquid outlet flow channel 314 and the second liquid outlet flow channel 315 are all constructed on the microfluidic chip, which can improve the integration of the microfluidic chip and is beneficial to the processing and forming of the sorting device.

[0218] Optionally, in combination Figure 3 , Figure 4 As shown, the flow channel assembly further includes a support frame 320. The support frame 320 includes a bottom plate, a first side plate 322 and a second side plate 323. The first side plate 322 and the second side plate 323 are oppositely arranged; wherein, the microfluidic chip is located between the first side plate 322 and the second side plate 323 and is lapped on the upward side of the bottom plate.

[0219] The support frame 320 is used to fix the microfluidic chip 310. Specifically, the bottom of the microfluidic chip 310 is lapped on the bottom plate of the support frame 320, and the two side ends of the microfluidic chip 310 are respectively clamped by the first side plate 322 and the second side plate 323 of the support frame 320. Adopting such a setting form is beneficial to the fixation of the microfluidic chip 310 and is convenient for identifying and observing the droplets in the droplet flow channel 311.

[0220] Optionally, the sorting device further includes an electrode mounting plate 840, a positive electrode connecting piece 831 and a negative electrode connecting piece 832. The electrode mounting plate 840 is fixed to the first side plate 322 and / or the second side plate 323 of the support frame 320; the positive electrode connecting piece 831 is fixed to the electrode mounting plate 840 and extends to the positive electrode flow channel 316 of the microfluidic chip, and the negative electrode connecting piece 832 is fixed to the electrode mounting plate 840 and extends to the negative electrode flow channel 317 of the microfluidic chip. The positive electrode connecting piece 831 is used to conductively connect the positive electrode to the power supply, and the negative electrode connecting piece is used to conductively connect the negative electrode to the power supply.

[0221] Adopting such a setting form, the positive electrode and the negative electrode of the electrode assembly can be conveniently connected to the power supply or disconnected from the power supply. In addition, the connection by means of the electrode connecting piece is tightly connected, and the positive electrode and the negative electrode are not easily faulty due to loose connection.

[0222] Optionally, the fluorescence signal detection device includes a laser assembly and a fluorescence detection assembly 500. Among them, the laser assembly is used to emit laser light to the magnetic particles drawn into a line, and the fluorescent markers in the droplets are excited by the laser light to emit fluorescence; the fluorescence detection assembly 500 is used to detect the fluorescence emitted by the fluorescent markers in the droplets.

[0223] After the droplet flows through the first section of the droplet flow channel 311, multiple particle clusters composed of magnetic particles in the droplet form a line. At this time, an excitation laser is emitted to the droplet by the laser assembly, and antigens and secondary antibodies in the multiple particle clusters emit fluorescence. Whether the droplet is a target droplet can be determined by detecting the fluorescence intensity of the antigen and the fluorescence intensity of the secondary antibody. With such a setting form, it is beneficial to perform fluorescence recognition on the droplet and can improve the accuracy of droplet recognition.

[0224] Optionally, the laser assembly includes a first laser light source 410 for emitting a laser of a first wavelength, and when one of the antigen and the secondary antibody is excited by the laser of the first wavelength, it emits fluorescence of the first wavelength; the fluorescence detection assembly 500 includes: a first fluorescence detector for detecting the fluorescence of the first wavelength.

[0225] With the first laser light source 410 and the first fluorescence detector provided, the fluorescence signal of the antigen or the secondary antibody can be detected, which is beneficial for the droplet sorting system to determine whether the droplet flowing through the droplet flow channel 311 is a target droplet.

[0226] Optionally, the laser assembly further includes a second laser light source 420, and the second laser light source 420 is used for emitting a laser of a second wavelength, and when the other of the antigen and the secondary antibody is excited by the laser of the second wavelength, it emits fluorescence of the second wavelength; the fluorescence detection assembly 500 further includes: a second fluorescence detector for detecting the fluorescence of the second wavelength.

[0227] Optionally, the bottom plate of the support frame 320 is provided with an observation window, and at least a first part of the microfluidic chip corresponding to the observation window is made of a transparent material; wherein, the light emitting direction of the laser assembly faces the observation window; and / or, the detection position of the fluorescence detection assembly 500 corresponds to the observation window.

[0228] With such a setting form, it is beneficial for the laser to act on the particle clusters in the droplet and is beneficial for the fluorescence detection assembly 500 to receive the fluorescence signal of the particle clusters.

[0229] The laser assembly emits a laser of the first wavelength and a laser of the second wavelength to excite the fluorescence signal in the antigen and the secondary antibody. This can further improve the accuracy of droplet recognition.

[0230] Optionally, the fluorescence detection assembly 500 includes a photomultiplier tube.

[0231] The photomultiplier tube can amplify the optical signal and convert it into an electrical signal, thereby reflecting the strength of the fluorescence signal. The fluorescence detection assembly 500 including a photomultiplier tube can improve the accuracy of droplet recognition.

[0232] Optionally, the fluorescence detection component 500 includes a first photomultiplier tube 510 and a second photomultiplier tube 520. The first photomultiplier tube 510 is used to detect the fluorescence signal of the antigen, and the second photomultiplier tube 520 is used to detect the fluorescence signal of the secondary antibody.

[0233] By detecting two fluorescence signals through the first photomultiplier tube 510 and the second photomultiplier tube 520, the interference between fluorescence signals can be reduced or avoided, which is beneficial to improving the accuracy of droplet recognition.

[0234] Optionally, the laser component includes a first laser light source 410 and a second laser light source 420. The first laser light source 410 is used to excite the fluorescent substance of the antigen, and the second laser light source 420 is used to excite the fluorescent substance of the secondary antibody.

[0235] Optionally, the light emitted by the laser component is directed towards the observation window.

[0236] Adopting such a setting form is beneficial for the laser component to excite the fluorescent substance in the particle cluster.

[0237] Optionally, the detection position of the fluorescence detection component 500 corresponds to the observation window.

[0238] Adopting such a setting form is beneficial for the fluorescence detection device to detect the fluorescence signal in the droplet.

[0239] Optionally, the laser component further includes a coaxial system 430. The coaxial system 430 is used to guide the laser of the first wavelength and the laser of the second wavelength to the droplet in the droplet flow channel 311, and the coaxial system 430 is further used to guide the fluorescence of the first wavelength and the fluorescence of the second wavelength in the droplet flow channel 311 to the first fluorescence detector and the second fluorescence detector.

[0240] The laser component includes an optical path coaxial system 430. The installation positions of the first laser light source 410 and the second laser light source 420 are not restricted, which is beneficial to the miniaturization of the droplet sorting system. The optical axis collimation of the optical path coaxial system 430 is relatively high, the transmission loss of the laser is small, and the laser transmission efficiency is high.

[0241] Optionally, the droplet sorting system further includes a fluorescence signal detection device. The fluorescence signal detection device includes a light source component 620 and an imaging component. The light emitting direction of the light source component 620 is towards the droplet in the first magnetic field; the imaging component, and the imaging position is towards the droplet in the first magnetic field.

[0242] By setting the imaging component, the image information of the target droplet can be obtained, which facilitates the user to observe and analyze the target droplet. By setting the imaging component, the image information of the suspected target droplet can also be obtained, so that the user can adjust the setting parameters of the droplet sorting system through the image of the suspected target droplet to further improve the accuracy of droplet recognition.

[0243] Optionally, the imaging component includes a high-speed camera 610.

[0244] Optionally, the imaging component includes a high-speed camera 610. The lens of the high-speed camera 610 faces the droplet in the first magnetic field, and the shutter of the high-speed camera 610 is opened synchronously with the light source component 620.

[0245] Even when the droplet is flowing at high speed, the high-speed camera 610 can still obtain a relatively clear droplet pattern. The imaging component includes a high-speed camera 610, which can increase the flow speed of the droplet. With such a setting, the light pollution of the light source component 620 can be reduced, and the service life of the light source component 620 can be increased.

[0246] To confirm whether there are target particle clusters in the droplet, fluorescence recognition can be performed on the antigens and antibodies in the target particle clusters. Specifically, the droplet is irradiated with a first laser and / or a second laser. The fluorescent substance in the antigen can emit a first fluorescence under the excitation of the first laser, and the fluorescent substance in the secondary antibody can emit a second fluorescence under the excitation of the second laser. If the intensity and / or characteristic peak of the first fluorescence and / or the second fluorescence both meet the preset conditions, then the droplet is considered a target droplet.

[0247] In actual operation, the antigens and secondary antibodies with fluorescent substances are distributed in each droplet. In some cases, even if the secondary antibody in the droplet is not bound to the antibody, the laser can still excite the unbound secondary antibody, resulting in a second fluorescence that interferes with the judgment. In other cases, even if the secondary antibody in the droplet is bound to the antibody, due to the relatively irregular distribution of the target particle clusters, the characteristic peaks of the fluorescence emitted by the fluorescent substances in the antigen and the secondary antibody excited by the laser are not obvious, which also easily leads to misjudgment.

[0248] Before or when the laser excites the fluorescent substance, a magnetic field is applied to the droplet, so that the target particle clusters can be arranged according to a certain rule. This can reduce the misjudgment of the target droplets. Specifically, the magnetic particles are paramagnetic magnetic particles. The magnetic particles themselves do not have magnetism, which can avoid the aggregation of magnetic particles during or before the incubation of the sample solution, thus affecting the binding of magnetic particles to antibodies. The paramagnetic magnetic particles are magnetized in the magnetic field and exhibit magnetism, so they are distributed along the magnetic induction lines of the magnetic field. The positions of the magnetic particles change, and the particle clusters with magnetic particles as the key components are distributed in the droplet according to a certain rule. The secondary antibodies not bound to the antibody do not follow this rule. When the laser is applied to the droplet, the target particle clusters distributed according to a certain rule emit fluorescence. At this time, if the characteristic peak of the first fluorescence in the particle cluster is relatively obvious, it is considered that the recognition is effective. Further, if the characteristic peak of the second fluorescence meets the preset conditions, then the droplet is considered a target droplet.

[0249] After entering the magnetic field, the unmagnetized magnetic particles are first magnetized. A magnetic domain is a region within a ferromagnetic material where the atomic magnetic moments (i.e., the spin magnetic moments of electrons) are aligned, forming a local magnetization region. In the absence of an external magnetic field, these magnetic domains are randomly arranged within the material, resulting in the material not exhibiting magnetism macroscopically. When an external magnetic field acts on the ferromagnetic material, the magnetic moments of these magnetic domains tend to align with the external magnetic field, causing the material to exhibit magnetism. The magnetic domains are rearranged along the direction of the magnetic induction lines in the magnetic field, causing the magnetic particles to exhibit magnetism macroscopically. If the direction of the magnetic induction lines changes significantly as the droplet flows, the magnetization effect on the magnetic particles is poor. If the direction of the magnetic induction lines changes slightly as the droplet flows, the initial position of the magnetic particles in the magnetic field is more likely to be the position where they are located after being magnetized in the magnetic field. That is, after the unmagnetized magnetic particles enter the magnetic field, they are not easily distributed according to a certain rule or along a straight line or curve, affecting the droplet recognition result.

[0250] The droplet sorting system provided by the embodiments of the present disclosure further includes a fluorescence signal enhancement device. The fluorescence signal enhancement device is used to enhance the fluorescence signal of the droplet so that the target droplet can be easily recognized by the fluorescence signal detection device in the droplet flow channel 311.

[0251] This can improve the accuracy of fluorescence signal recognition.

[0252] Optionally, the fluorescence signal enhancement device includes a magnet assembly 200. The magnet assembly 200 is used to generate a first magnetic field, and the magnetic particles in the droplet are pulled into a line shape in the first magnetic field.

[0253] This can make the magnetic particles in the droplet arranged more regularly, so that the fluorescence signal characteristic peak is obvious, which is beneficial for the droplet sorting system to recognize the target droplet.

[0254] Optionally, as shown in Figures 5 to 8 The magnet assembly 200 includes a first magnet 210 and a second magnet 220. Among them, the first magnet 210 is arranged on one side of the droplet flow channel 311; the second magnet 220 is arranged on the other side of the droplet flow channel 311; among them, the length direction of the droplet flow channel 311 is along the direction of cutting the magnetic induction lines between the first magnet 210 and the second magnet 220.

[0255] The surface of the first magnet 210 facing the second magnet 220 and the surface of the second magnet 220 facing the first magnet 210 are opposite magnetic poles. In this way, the magnetic induction lines between the first magnet 210 and the second magnet 220 are straight lines, which is beneficial to pulling the magnetic particles pre-magnetized by the pre-magnetization assembly in the droplet into a straight line, thereby enhancing the fluorescence signal to improve the accuracy of droplet recognition.

[0256] Optionally, the magnet assembly 200 includes a first magnet 210 and a second magnet 220. The first magnet 210 is disposed on the inner surface of the first side plate 322, and the second magnet 220 is disposed on the inner surface of the second side plate 323.

[0257] The side of the first magnet 210 facing the second magnet 220 and the side of the second magnet 220 facing the first magnet 210 have opposite magnetic poles. In this way, the magnetic induction lines between the first magnet 210 and the second magnet 220 are straight lines, which is beneficial to pulling the particle clusters including magnetic particles into a straight line, thereby enhancing the fluorescence signal to improve the accuracy of droplet identification. The first magnet 210 and the second magnet 220 are respectively fixed to the first side plate 322 and the second side plate 323 of the support frame 320, which is beneficial to fixing the magnet assembly 200.

[0258] Optionally, in combination Figures 5 to 8 As shown, the fluorescence signal enhancement device further includes a pre-magnetization assembly for generating a pre-magnetization magnetic field. The magnetic particles in the droplet agglomerate in the pre-magnetization magnetic field, and the agglomerated magnetic particles are pulled into a line in the first magnetic field.

[0259] The magnetic particles are rearranged in the pre-magnetization magnetic field according to the direction of the magnetic induction lines of the pre-magnetization magnetic field, so as to exhibit magnetism macroscopically. It should be noted that during and after the magnetization of the magnetic particles, under the action of the magnetic field force and the Brownian motion of the magnetic particles, the magnetic particles approach each other and become an agglomerated state. The agglomerated state can be defined as the magnetic particles inside the droplet attracting and approaching each other.

[0260] The first magnetic field is located at the subsequent stage of the pre-magnetization magnetic field. The pre-magnetized magnetic particles enter the first magnetic field formed by the magnet assembly 200 along with the droplet. Since the magnetic particles are in a magnetized state, they are not easily remagnetized by the first magnetic field, but tend to rotate or move in the first magnetic field so that the magnetic induction lines inside the magnetic particles tend to be in the same direction as the magnetic induction lines of the first magnetic field. In this case, when the magnetic induction lines in the first magnetic field are straight lines, multiple magnetic particles are distributed along a straight line, and when the magnetic induction lines in the first magnetic field are curved lines, multiple magnetic particles are distributed along a curved line. In addition, the multiple magnetic particles entering the first magnetic field are in an agglomerated state, and the agglomerated magnetic particles are distributed along the same or adjacent magnetic induction lines in the first magnetic field under the action of the magnetic field force of the first magnetic field. In this way, the distribution of the magnetic particles in the first magnetic field can be made more regular, which is beneficial to reducing the misjudgment caused by the irregular distribution of the magnetic particles, thereby improving the accuracy of droplet identification.

[0261] After the magnetic particles in the droplet are drawn into a line, the antigen and / or secondary antibody bound to the magnetic particles are recognized by the fluorescence signal detection device. The fluorescence signal detection device marks the droplets that meet the conditions as target droplets, and the sorting device deflects the target droplets to the first outlet channel 314 when the target droplets flow through the outlet section of the droplet flow channel 311.

[0262] Combined Figure 9 As shown, the distribution of non-pre-magnetized magnetic particles and particle clusters is relatively dispersed; combined Figure 10 As shown, the distribution of pre-magnetized magnetic particles and particle clusters is in an aggregated state.

[0263] Combined Figure 11 As shown, when non-pre-magnetized droplets enter the first magnetic field, the particle clusters are drawn into multiple thin lines. Combined Figure 12 As shown, when pre-magnetized droplets enter the first magnetic field, the particle clusters are drawn into a thick line.

[0264] Combined Figure 13 As shown, Figure 13 In the left peak is the fluorescence intensity characteristic peak when non-pre-magnetized droplets enter the first magnetic field, and the right peak is the fluorescence signal characteristic peak when pre-magnetized droplets enter the first magnetic field. It can be seen that the characteristic peak is more obvious when pre-magnetized droplets enter the first magnetic field, which is beneficial to the fluorescence signal recognition of droplets.

[0265] Using the droplet sorting system provided by the embodiments of the present disclosure, by setting the pre-magnetization assembly 100, the magnetic particles can be magnetized before entering the first magnetic field to form an aggregated state. The magnetized and aggregated magnetic particles can be drawn into a line after entering the first magnetic field, so that the fluorescent substances in the particle clusters can be more fully excited by the laser, thereby improving the recognition accuracy of the droplets.

[0266] Using the pre-magnetization assembly 100 to generate a pre-magnetization magnetic field can magnetize and aggregate the magnetic particles in the droplets. The magnetic particles in the pre-magnetized droplets are drawn into a line in the first magnetic field of the magnet assembly 200. The magnetic particles drawn into a line emit fluorescence under the excitation of the fluorescence signal detection device, and the characteristic peak of the fluorescence signal is obvious. Adopting such a setting form is beneficial to the droplet sorting system to identify target droplets.

[0267] Optionally, the magnetic field intensity of the pre-magnetization magnetic field is greater than the magnetic field intensity of the first magnetic field.

[0268] The intensity of the pre-magnetization magnetic field is relatively high, which can increase the magnetization speed of the magnetic particles. The magnetic field intensity of the first magnetic field is relatively low, which can reduce or avoid the re-magnetization of the magnetic particles in the first magnetic field, and is beneficial to the magnetic particles in the droplets being drawn into a line in the first magnetic field.

[0269] The pre-magnetization of the magnetic particles in the droplets can be carried out in a container or in a pipeline. When carried out in a container, the droplets are in a static state. The container containing the droplets is placed in a pre-magnetization magnetic field, and the magnetic particles in the droplets are magnetized. This form facilitates the control of the magnetization of the magnetic particles. When carried out in a pipeline, the droplets are in a flowing state. The pipeline through which the droplets flow is placed in a pre-magnetization magnetic field, and the magnetic particles in the droplets are magnetized during the flowing process. This form facilitates driving the droplets to flow and is conducive to the pre-magnetized droplets entering the subsequent first magnetic field.

[0270] Optionally, optionally, combine Figures 5 to 8 As shown, the pre-magnetization assembly 100 includes a pre-magnetization pipeline 110 and a pre-magnetization magnet 120. The pre-magnetization pipeline 110 defines a pre-magnetization flow channel for the droplets to flow through; the pre-magnetization magnet 120 is used to generate a pre-magnetization magnetic field, and at least part of the pre-magnetization flow channel is located in the pre-magnetization magnetic field.

[0271] The pre-magnetization pipeline 110 defines a first flow channel, and the pre-magnetization magnet forms a pre-magnetization magnetic field. At least part of the first flow channel is located in the pre-magnetization magnetic field. When the droplets flow through the part of the first flow channel located in the pre-magnetization magnetic field, they are magnetized in the pre-magnetization magnetic field. The pre-magnetization assembly 100 includes a pre-magnetization pipeline 110 and a pre-magnetization magnet, which is conducive to the fluorescence signal enhancement device magnetizing the magnetic particles in the droplets and causing the magnetic particles to agglomerate. Since the pre-magnetization of the droplets is carried out in the pre-magnetization pipeline 110, the droplets can be pre-magnetized in a flowing state. In this way, the pre-magnetization of the magnetic particles in the droplets can be carried out continuously, thereby improving the continuity of the pre-magnetization of the droplets by the fluorescence signal enhancement device.

[0272] Optionally, the pre-magnetization flow channel is connected to the droplet flow channel 311, and the droplet flow channel 311 is located at the subsequent stage of the pre-magnetization flow channel along the droplet flow direction.

[0273] After passing through the pre-magnetization assembly 100, the droplets enter the droplet flow channel 311 and are drawn into a linear shape when flowing through the first section of the droplet flow channel 311. Adopting such a setting form is conducive to the fluorescence signal recognition of the droplets and is also conducive to the observation and photographing of the droplets. Adopting such a setting form, the droplets flow continuously in the pre-magnetization flow channel and the droplet flow channel 311, which can improve the continuous working ability of the fluorescence signal enhancement device.

[0274] Optionally, the pre-magnetization magnet includes a first pre-magnetization magnet 121 and a second pre-magnetization magnet 122. Among them, the first pre-magnetization magnet 121 is arranged on one side of the pre-magnetization pipeline 110; the second pre-magnetization magnet is arranged on the other side of the pre-magnetization pipeline 110.

[0275] The first pre-magnetized magnet 121 and the second pre-magnetized magnet 122 are arranged opposite to each other, with the N pole of the first pre-magnetized magnet 121 facing the S pole of the second pre-magnetized magnet 122, or the S pole of the first pre-magnetized magnet 121 facing the N pole of the second pre-magnetized magnet 122. A straight-line form of magnetic induction lines is formed between the first pre-magnetized magnet 121 and the second pre-magnetized magnet 122. When the droplet flows through the pre-magnetized magnet, the direction of the magnetic induction lines remains generally unchanged, which can improve the magnetization effect on the magnetic particles.

[0276] The first pre-magnetized and the second pre-magnetized magnets 122 are arranged on both sides of the pre-magnetized pipeline 110. The magnetic force between the first pre-magnetized magnet 121 and the second pre-magnetized magnet 122 acts on the droplets in the pre-magnetized pipeline 110. By changing the distance between the first pre-magnetized magnet and the second pre-magnetized magnet 122, the intensity of the pre-magnetized magnetic field can be changed. In addition, the pre-magnetized magnet and the pre-magnetized pipeline 110 are in a separate setting form, which facilitates the user to assemble and maintain the pre-magnetized component 100.

[0277] Optionally, the microfluidic chip 310 is further configured with a pre-magnetized flow channel. The part of the microfluidic chip 310 configured with the pre-magnetized flow channel serves as the above-mentioned pre-magnetized pipeline 110. After the droplet flows through the pre-magnetized flow channel, it enters the sample liquid inflow channel 313.

[0278] Adopting such a setting form can improve the integration degree of the droplet sorting system, thereby reducing the cost of the droplet sorting system.

[0279] Optionally, the pre-magnetized magnet includes a first pre-magnetized magnet 121 and a second pre-magnetized magnet 122, and the first pre-magnetized magnet 121 and the second pre-magnetized magnet 122 are respectively arranged on the upper and lower surfaces of the microfluidic chip 310.

[0280] Adopting such a setting form, when the droplet flows in the pre-magnetized flow, the flow direction is along the direction of cutting the magnetic induction lines of the pre-magnetized magnet, which is beneficial to magnetizing the magnetic particles in the droplet. In addition, when the magnetic particles flow with the droplet, the distances from the first pre-magnet and the second pre-magnetized magnet 122 do not change too much, which can reduce or avoid damage to the sample caused by the magnetized magnetic particles squeezing the droplet when moving towards the first pre-magnetized magnet 121 or the second pre-magnetized magnet 122.

[0281] Optionally, the pre-magnetized magnet includes a pre-magnetized coil 123. The pre-magnetized coil 123 is wound around the pre-magnetized pipeline 110, and the axis of the pre-magnetized coil 123 is along the length direction of the pre-magnetized pipeline 110. When the coil is energized, a pre-magnetized magnetic field is generated.

[0282] The pre-magnetization coil 123 is wound around the pre-magnetization pipeline 110 in a spiral shape. When the pre-magnetization coil 123 is energized, an electromagnet is formed, and the electromagnet is used to generate a pre-magnetization magnetic field. The axis of the pre-magnetization coil 123, that is, the line around which the pre-magnetization coil 123 spirals, and the two ends of the pre-magnetization pipeline 110 serve as the N pole and the S pole respectively. Adopting such a setting form is beneficial to reducing the volume of the pre-magnetization assembly 100, and the intensity of the pre-magnetization magnetic field can be adjusted by adjusting the current intensity and / or the number of turns of the pre-magnetization coil 123.

[0283] Optionally, the pre-magnetization magnet is used to generate a pre-magnetization magnetic field with a changing direction. When the magnetic particles in the droplet are in the pre-magnetization flow channel, they move and agglomerate under the action of the changing magnetic field force.

[0284] The magnetic particles in the droplet will not only be magnetized in the pre-magnetization magnetic field, but also rotate and move under the action of the magnetic force, thus agglomerating. The magnetic particles can be magnetized in a relatively short time, but it takes more time to agglomerate. When the direction of the pre-magnetization magnetic field changes, the movement of the magnetic particles in the magnetic field will be intensified, thus accelerating the agglomeration of the magnetic particles. Adopting such a setting form can improve the agglomeration effect of the magnetic particles in the droplet in the pre-magnetization magnetic field.

[0285] Optionally, the pre-magnetization magnet includes a plurality of magnet pairs. The plurality of magnet pairs are arranged close to the pre-magnetization flow channel. Magnetic induction lines are formed between each magnet pair, and the directions of the magnetic induction lines of the plurality of magnet pairs are different to form a pre-magnetization magnetic field with a changing direction.

[0286] As an implementation form of generating a pre-magnetization magnetic field with a changing direction, the pre-magnetization magnet includes a plurality of magnet pairs. Each magnet pair includes two magnets with opposite N and S poles. The plurality of magnet pairs are arranged along the length direction of the pre-magnetization flow channel, and the two magnets of each magnet pair are respectively opposite to both sides of the pre-magnetization flow channel. The directions of the magnetic induction lines inside the plurality of magnet pairs are different, so the direction of the magnetic force received by the droplet when flowing through the pre-magnetization flow channel also changes. Adopting such a setting form is beneficial to the agglomeration of the magnetic particles in the droplet in the pre-magnetization magnetic field.

[0287] Optionally, the plurality of magnet pairs are distributed in a spiral shape.

[0288] The plurality of magnet pairs are distributed in a form similar to the helix of an RNA molecule. In this way, the magnetic force received by the droplet when flowing through the pre-magnetization pipeline 110 rotates in one direction. This can better make the magnetic particles rotate and move in the pre-magnetization magnetic field and thus agglomerate.

[0289] Optionally, the pre-magnetizing magnet includes an electromagnet, and a pre-magnetizing magnetic field with a changing direction is formed by adjusting the current intensity and / or current direction of the electromagnet; or, the pre-magnetizing magnet includes a coil wound around the pre-magnetizing pipeline 110, and a pre-magnetizing magnetic field is generated when the coil is energized, and a pre-magnetizing magnetic field with a changing direction is formed by adjusting the current intensity and / or current direction of the coil.

[0290] When the current direction of the electromagnet is changed, the magnetic field direction of the electromagnet changes; when the current intensity of the electromagnet is changed, the magnetic field intensity of the electromagnet changes. The pre-magnetizing assembly 100 includes an electromagnet, and the pre-magnetizing assembly 100 can form a pre-magnetizing magnetic field with a changing direction by changing the current direction and / or current intensity.

[0291] When the pre-magnetizing magnet includes the pre-magnetizing coil 123 wound around the pre-magnetizing pipeline 110, a pre-magnetizing magnetic field with a changing direction can also be formed by changing the current direction and / or current intensity.

[0292] When the magnetic field intensity and / or magnetic field direction of the pre-magnetizing magnetic field change, the magnetic particles in the droplet can be magnetized and agglomerated more fully, which is beneficial to pulling the magnetic particles into a line shape in the first magnetic field.

[0293] Optionally, the pre-magnetizing flow channel is a flow channel with a changing direction, and at least part of the flow channel with a changing direction is located in the pre-magnetizing magnetic field. When the magnetic particles in the droplet move in the flow channel with a changing direction, they are affected by the acting force of the first magnetic field and move to agglomerate.

[0294] When the magnetic field direction remains unchanged, the pre-magnetizing flow channel is a flow with a changing direction. When the droplet flows in the pre-magnetizing flow channel, the force of the pre-magnetizing magnet that the magnetism in the droplet receives in the pre-magnetizing magnetic field changes, and in this way, the agglomeration of the magnetism in the droplet in the pre-magnetizing magnetic field can also be accelerated.

[0295] It should be noted that when the magnetic field direction and / or magnetic field intensity change, the direction of the pre-magnetizing flow channel also changes, which can further accelerate the movement of the magnetic particles in the droplet in the pre-magnetizing magnetic field, so that the magnetic particles in the droplet agglomerate.

[0296] Optionally, the pre-magnetizing flow channel includes a plurality of bending segments, and the plurality of bending segments are connected end to end to form a pre-magnetizing flow channel with a changing direction.

[0297] As an implementation form of the pre-magnetized flow channel for a flow channel with a changing direction, the pre-magnetized flow channel includes a plurality of bending segments. The plurality of bending segments are U-shaped or S-shaped, and the plurality of bending segments are connected end to end. With such a setting form, not only can the magnetic particles in the droplet be subjected to a magnetic field force with a changing direction, but also the flow formation of the droplet in the pre-magnetized magnetic field can be increased, thereby enhancing the pre-magnetization effect and agglomeration effect of the magnetic particles in the droplet by increasing the residence time of the droplet in the pre-magnetized magnetic field.

[0298] Optionally, the pre-magnetized flow channel is a spiral flow channel.

[0299] When the pre-magnetized flow channel is a spiral flow channel, the droplet is also subjected to a centrifugal force in the pre-magnetized flow channel. When the droplet moves along the spiral flow channel, the antigen, antibody, secondary antibody, and magnetic particles in the droplet tend to move to the outside of the pre-magnetized flow channel under the action of the centrifugal force. This is not only conducive to the specific binding between the antigen, antibody, secondary antibody, and magnetic particles, but also conducive to the agglomeration of the magnetized magnetic particles.

[0300] Optionally, the pre-magnetized pipeline 110 is wound around the pre-magnetized magnet to form a flow channel with a changing direction.

[0301] In the form that the pre-magnetized pipeline 110 is wound around the pre-magnetized magnet, the pre-magnetized magnet can play a role in fixing the pre-magnetized pipeline 110, which can improve the structural rigidity of the pre-magnetized assembly 100. In addition, in the form that the pre-magnetized pipeline 110 is wound around the pre-magnetized magnet, the volume of the pre-magnetized assembly 100 can be reduced.

[0302] When the pre-magnetized pipeline 110 is wound around the pre-magnetized magnet, on the one hand, when the size of the pre-magnetized magnet is limited, the length of the pre-magnetized pipeline 110 can be increased, thereby increasing the residence time of the droplet in the pre-magnetized magnetic field. This can improve the pre-magnetization effect of the pre-magnetized magnetic field on the magnetic particles. On the other hand, in the form that the pre-magnetized pipeline 110 is wound around the pre-magnetized magnet, the radial direction of the pre-magnetized pipeline 110 is along the direction of cutting the magnetic induction lines of the pre-magnetized magnet. When the droplet flows in the pre-magnetized pipeline 110, the magnetic induction lines acting on the magnetic particles are along generally the same direction, which can further improve the pre-magnetization effect of the pre-magnetized magnetic field on the magnetic particles.

[0303] Optionally, the pre-magnetized magnetic field includes a first part and a second part. The magnetic field direction of the first part remains unchanged, and the magnetic field direction of the second part changes with time.

[0304] The magnetic particles in the droplet will be magnetized in the pre-magnetized magnetic field, and the magnetized magnetic shells will agglomerate during the flow process in the pre-magnetized magnetic field and after leaving the pre-magnetized magnetic field. For the agglomeration of the magnetic particles, it is beneficial for the magnetic field direction of the pre-magnetized magnetic field to change; for the magnetization of the magnetic particles, it is beneficial for the magnetic field direction of the pre-magnetized magnetic field to remain unchanged.

[0305] Therefore, the pre-magnetizing magnetic field includes a first part and a second part. The magnetic field direction of the first part remains unchanged, while the magnetic field direction of the second part changes with time. In this way, the magnetic particles are magnetized in the first part of the pre-magnetizing magnetic field and agglomerate in the second part of the pre-magnetizing magnetic field. Although the magnetic particles will still be magnetized in the second part of the pre-magnetizing magnetic field and agglomeration will also occur in the first part of the pre-magnetizing magnetic field, such a setting form can separate the pre-magnetization and agglomeration of the magnetic particles to a certain extent, thereby improving the magnetization effect and agglomeration effect of the magnetic particles.

[0306] Optionally, the pre-magnetizing magnet includes an alternating current electromagnet, and the second part of the pre-magnetizing magnetic field is formed when the alternating current electromagnet is energized.

[0307] The magnetic field direction of the alternating current electromagnet changes with the change of the current direction, and the magnetic particles can move more in the second part of the pre-magnetizing magnetic field, so as to agglomerate better.

[0308] Optionally, the pre-magnetizing magnet includes a direct current electromagnet, and the first part of the pre-magnetizing magnetic field is formed when the direct current electromagnet is energized.

[0309] The magnetic field direction of the direct current electromagnet remains unchanged, and the magnetic field intensity of the first part of the pre-magnetizing magnetic field formed by the direct current electromagnet is easy to adjust.

[0310] Optionally, the pre-magnetizing pipeline 110 is a flexible hose, and the length of the part of the pre-magnetizing flow channel located in the pre-magnetizing magnetic field is adjusted by moving the pre-magnetizing pipeline 110.

[0311] For the pre-magnetization of magnetic particles, if the pre-magnetization time is short, the magnetization effect is not obvious, and it is not easy for magnetic particles to reach an ideal agglomerated state. If the pre-magnetization time is long, it is not easy for the agglomerated magnetic particles to be drawn into a linear shape in the first magnetic field. When the flow rate of the droplets is constant, the length of the pre-magnetization pipeline 110 located in the pre-magnetization magnetic field determines the residence time of the droplets in the pre-magnetization magnetic field. For different droplets, the required pre-magnetization time and magnetic field strength are also different. When the magnetic field strength is constant, by adjusting the length of the part of the pre-magnetization pipeline 110 located in the pre-magnetization magnetic field, the pre-magnetization time of the droplets in the pre-magnetization magnetic field can be adjusted. With such a setting, it is convenient for users to adjust the pre-magnetization degree of the droplets as needed. Since the length of the pre-magnetization pipeline 110 located in the pre-magnetization magnetic field is adjustable, the pre-magnetization time can be adjusted by adjusting the length of the part of the pre-magnetization pipeline 110 located in the pre-magnetization magnetic field, so that the magnetic particles in the droplets can achieve a preset pre-magnetization effect. Exemplarily, as a way of length adjustment, the pre-magnetization pipeline 110 is a flexible pipeline, and the length of the part of the pre-magnetization pipeline 110 located in the pre-magnetization magnetic field is adjusted by changing the number of turns of the pre-magnetization pipeline 110 in the pre-magnetization magnetic field.

[0312] Optionally, at least a part of the pre-magnetization pipeline 110 is spirally arranged in the pre-magnetization magnetic field.

[0313] With such a setting, on the one hand, the length of the pre-magnetization pipeline 110 can be increased, thereby increasing the residence time of the droplets in the pre-magnetization magnetic field, and further improving the pre-magnetization effect of the pre-magnetization magnetic field on the magnetic particles. It should be noted that at the initial stage when the magnetic particles enter the pre-magnetization magnetic field, N poles and S poles are macroscopically presented. During the subsequent movement of the droplets, the magnetic particles can make the magnetic induction lines inside them tend to be consistent with the magnetic induction lines of the pre-magnetization magnetic field under the action of the magnetic field force, that is, the magnetic particles rotate themselves to adapt to the change of the direction of the magnetic induction lines of the pre-magnetization magnetic field. Although the spiral pre-magnetization pipeline 110 causes multiple changes in the direction of the magnetic induction lines in the radial direction of the pre-magnetization pipeline 110, increasing the residence time of the magnetic particles in the pre-magnetization magnetic field can generally improve the pre-magnetization effect on the magnetic particles.

[0314] Optionally, the droplet sorting system further includes a carrier plate 710 and a fixing component 720, wherein the carrier plate 710 is provided with an installation window; the fixing component 720 is used to fix the flow channel component 300 to the installation window.

[0315] The flow channel component 300 is fixed to the installation window, and the droplet flow channels 311 of the microfluidic chip 310 are exposed on both the downward side and the upward side, which is conducive to fluorescence identification and observation of the droplets in the droplet flow channels 311.

[0316] Optionally, the light source assembly 620 is disposed below the carrier plate 710.

[0317] With such an arrangement, the influence of ambient light on the light source assembly 620 can be reduced. In addition, the carrier plate 710 can serve as a protective plate for the light source assembly 620 to prevent the light source assembly 620 from shifting or being damaged when the user operates the droplet sorting system.

[0318] Optionally, the fluorescence recognition assembly is disposed below the carrier plate 710.

[0319] Similarly, this can reduce the influence of ambient light on the fluorescence recognition assembly. In addition, the carrier plate 710 also serves as a protective plate for the fluorescence recognition assembly to prevent the fluorescence recognition assembly from shifting or being damaged when the user operates the droplet sorting system.

[0320] Optionally, the high-speed camera 610 is disposed below the carrier plate 710.

[0321] This can reduce the influence of ambient light on the high-speed camera 610. In addition, the carrier plate 710 also serves as a protective plate for the high-speed camera 610 to prevent the high-speed camera 610 from shifting or being damaged when the user operates the droplet sorting system.

[0322] Optionally, the fixing assembly 720 includes a first clamping member 721 and a second clamping member 722. The first clamping member 721 is used to fix the first end of the flow channel assembly 300, and the second clamping member 722 is used to fix the second end of the flow channel assembly 300.

[0323] By clamping both ends of the flow channel assembly 300 with the first clamping member 721 and the second clamping member 722, the flow channel assembly 300 can be better fixed to the carrier plate 710.

[0324] Optionally, the pre-magnetization assembly 100 is fixed to the carrier plate 710.

[0325] With such an arrangement, it not only facilitates the installation of the pre-magnetization assembly 100, but also is beneficial for the user to adjust the length of the pre-magnetization pipeline 110 located in the pre-magnetization magnetic field.

[0326] Optionally, the bottom plate of the support frame 320 is provided with an observation window. At least a first part of the microfluidic chip corresponding to the observation window is made of a transparent material, and the imaging position of the imaging assembly faces the first part of the observation window.

[0327] This is beneficial for the imaging device to acquire droplet images and can reduce or avoid the occlusion of the microfluidic chip by the imaging device.

[0328] Optionally, the fluorescence recognition assembly is disposed below the carrier plate 710.

[0329] Similarly, this can reduce the influence of ambient light on the fluorescence recognition component. In addition, the carrier plate 710 also serves as a protective plate for the fluorescence recognition component, preventing the fluorescence recognition component from shifting or being damaged when the user uses the droplet sorting system.

[0330] Optionally, at least a part of the upper surface of the microfluidic chip corresponding to the second part of the observation window is made of a transparent material, and the light emitted by the light source component 620 is directed towards the second part of the microfluidic chip.

[0331] The microfluidic chip can be entirely made of a transparent material, which is conducive to the fluorescence signal recognition of the droplets in the droplet flow channel 311 and the acquisition of images of the droplets in the droplets. The microfluidic chip can also be partially made of a transparent material. When the microfluidic chip is partially made of a transparent material, at least the part corresponding to the observation window is made of a transparent material. This is conducive to the imaging of the imaging device and the visual observation of the user on the droplets in the droplet flow channel 311.

[0332] Combined Figure 23 As shown, an embodiment of the present disclosure provides a droplet sorting method, including:

[0333] S31, the droplet sorting system applies a laser to the droplet to make the fluorescent label combined with the magnetic particles in the droplet emit light.

[0334] S41, the droplet sorting system marks the droplets that meet the fluorescence condition as target droplets.

[0335] S51, the droplet sorting system applies a deflecting force to the target droplet to deflect the droplet to the target droplet flow channel.

[0336] Exemplarily, the droplet sorting method is used to sort cells prepared into water-in-oil droplets. The droplets include at least one cell, a plurality of magnetic particles, a plurality of antibodies specifically binding to the magnetic particles, a plurality of antigens specifically binding to the antibodies, and / or secondary antibodies, and at least one of the antigen and / or secondary antibody is fluorescently stained.

[0337] The number of antigens and / or secondary antibodies bound to the magnetic particles is obtained by fluorescence signal detection, thereby indirectly obtaining the number of specific antibodies produced by the cells. If the number of specific antibodies produced by the cells is large, the cells are target cells, and the droplets containing the cells are target droplets.

[0338] When the target droplet is flowing, applying a deflecting force to the target droplet can make the target droplet deviate from its original flow state and move to the target position. By such a method, the sorting and enrichment of target cells can be achieved.

[0339] Optionally, as shown in Figure 20 S51, the droplet sorting system applies a deflecting force to the target droplet to deflect the droplet to the target droplet flow channel, including:

[0340] S100, the droplet sorting system obtains the flow rate of the target droplet.

[0341] S200, the droplet sorting system determines the first moment when the target droplet flows through the working area of the electrode assembly according to the flow rate of the target droplet.

[0342] S300, the droplet sorting system controls the multiple positive electrodes of the electrode assembly to be energized one by one starting from the first moment.

[0343] The sheath liquid inflow channel 312 is used to fill the sheath liquid, and the sheath liquid inflow channel is provided with a sheath liquid injection port 3121. The liquid inlet end of the sample liquid inflow channel 313 is used to fill the sample liquid, and the sample liquid injection channel is provided with a sample liquid injection port 3131. The sample liquid contains water-in-oil droplets, and the droplets at least include one sample such as cells, bacteria, viruses, etc. and several recognition markers.

[0344] When sorting droplets, the sheath liquid is injected from the sheath liquid injection port 3121, and the sample liquid is injected from the sample liquid injection port 3131. The sheath liquid enters the droplet flow channel 311 along the sheath liquid inflow channel 312, and the sample liquid enters the droplet flow channel 311 along the sample liquid inflow channel 313. The sheath liquid and the sample liquid are mixed in the liquid inlet section of the droplet flow channel 311, so that the droplets in the sample liquid can continue to flow along the droplet flow channel 311 at a certain distance and a certain speed.

[0345] When the droplet flows along the droplet flow 311, the sorting device identifies the target droplet, and the droplet sorting system obtains the flow rate of the target droplet. Exemplarily, the sorting device includes a fluorescence signal detection device, and the fluorescence signal detection device detects the fluorescence signal of the droplet and identifies the target droplet and the non-target droplet through the characteristics of the fluorescence signal.

[0346] In the case where the droplet flows at a constant speed or the flow rate of the droplet is determined, the droplet sorting system determines the first moment when the target droplet flows through the working area of the electrode assembly. Exemplarily, if the flow rate of the droplet is v, the distance that the droplet flows from being identified to the position of the electrode assembly in the droplet flow is s1, and the time required for the droplet to flow from the current position to the droplet assembly is t1, then there is:

[0347] t1 = s1 / v1;

[0348] The current moment delayed by t duration is the first moment when the target droplet flows through the working area of the electrode assembly.

[0349] The positive electrode and the negative electrode of the electrode assembly are located on the same side of the droplet flow channel, and the droplet sorting system controls the multiple positive electrodes of the electrode assembly to be energized one by one starting from the first moment. When the positive electrode is energized, an electric field acting on the target droplet in the target droplet is formed with the adjacent or nearby negative electrode, and an electrophoresis force is applied to pull the target droplet towards the side where the electrode assembly is located.

[0350] During the flow process, the target droplet deflects towards the side where the electrode assembly is located, and the deflected target droplet flows into the first liquid outlet channel 314. When the non-target droplet flows through the position where the electrode assembly is located, it is not affected by the electric field force and enters the second liquid outlet channel 315 under the action of inertia.

[0351] The target droplets that enter the first liquid outlet channel 314 flow along the first liquid outlet channel and flow out from the first liquid outlet 3141 to be collected. The non-target droplets that enter the second liquid outlet channel 315 flow along the second liquid outlet channel and flow out from the second liquid outlet 3151. In this way, a primary droplet sorting of the sample liquid is completed.

[0352] The working area of the electrode assembly is the area where the droplet flow channel can be affected by the electric field. When the target droplet flows through the working area of the electrode assembly, if multiple positive electrodes are energized, the target droplet is affected by multiple electric fields when flowing through the electrode assembly, and the target droplet in the target droplet is easily broken. In the droplet sorting method provided by the embodiments of the present disclosure, the droplet sorting system controls multiple electrodes to start one by one. The target droplet is only affected by one or two electric fields within the same time period, and the deflection of the target droplet is easy to control, and the droplet is not easily broken. In the droplet sorting method provided by the embodiments of the present disclosure, the electrode assembly can provide a continuous and uniform pulling force for the target droplet, so as to allow the droplet to pass through the droplet flow channel at a higher speed, which can significantly improve the sorting throughput; by providing a pulling force for the target droplet through multiple electrode units or multiple positive electrodes of the electrode assembly, the pulling force received by the target droplet is relatively gentle, and the droplet is not easily broken.

[0353] Optionally, as shown in Figure 21 Step S100 of the droplet sorting system obtaining the flow rate of the target droplet includes:

[0354] S111, the droplet sorting system determines the first time required for the droplet to flow through the fluorescence signal detection device according to the wave width of the fluorescence signal.

[0355] S112, the droplet sorting system determines the flow rate of the droplet according to the first time and the working length of the fluorescence signal detection device.

[0356] For the precise sorting of droplets, it is necessary to accurately judge the moment when the target droplet flows through the sorting device. As shown in Figure 13As shown, the abscissa is time and the ordinate is the fluorescence signal intensity. When the target droplet flows through the fluorescence signal detection device, the fluorescence signal intensity first increases and then decreases with time, which is reflected as a peak in the intensity-time graph of the fluorescence signal. When the sample size in the droplet is relatively uniform and the position of the fluorescence signal detection device remains unchanged, the moving distance of the droplet corresponding to the peak (i.e., the working length of the fluorescence signal detection device) is constant. Exemplarily, if the working length of the fluorescence signal detection device is s2 and the width of the peak is t2, then:

[0357] V = s2 / t2;

[0358] In this way, the flow rate of the droplet can be accurately determined according to the peak width of the fluorescence signal and the working length of the fluorescence signal detection device. In addition, the fluorescence signal detection device is used to identify the target droplet and determine the flow rate of the target droplet at the same time, which can reduce the volume of the dispensing device and the cost of the sorting device.

[0359] In addition, using the fluorescence signal wave width to determine the above-mentioned first duration is sensitive and has a relatively fast detection speed, allowing the droplet to flow through the fluorescence signal detection device at a higher speed. This can increase the throughput of the sorted droplets.

[0360] Optionally, as shown in Figure 22 Step S100 of the droplet sorting system to obtain the flow rate of the target droplet includes:

[0361] S121, the droplet sorting system controls the high-speed camera to continuously capture droplet images at intervals of a second duration.

[0362] S122, the droplet sorting system compares the continuously captured droplet images to determine the displacement distance of the droplet.

[0363] S123, the droplet sorting system determines the flow rate of the droplet according to the droplet displacement distance and the second duration.

[0364] The ratio of the displacement distance determined by the comparison unit to the second duration can accurately reflect the flow rate of the droplet. In the case where it is necessary to record the droplet image by a high-speed camera, this method has a lower cost and accurate results. In addition, the high-speed camera is used to take pictures of the target droplet and determine the flow rate of the target droplet at the same time, which can reduce the volume of the dispensing device and the cost of the sorting device.

[0365] Determining the flow rate of the droplet through the droplet image can improve the accuracy of the obtained droplet flow rate when the sample size in the droplet is not uniform. Since the droplet flow rate is more accurate, the droplet sorting system can more precisely control the energization of the positive electrode or energize one by one. This can improve the accuracy of sorting droplets.

[0366] Optionally, as shown in Figure 21As shown, step S300 controls the multiple positive electrodes of the electrode assembly of the droplet sorting system to be energized one by one starting from the first moment, including:

[0367] S311, the droplet sorting system determines the energization interval of the electrodes according to the flow rate of the target droplet.

[0368] S312, the droplet sorting system controls the multiple electrodes of the electrode assembly to be energized one by one starting from the first moment according to the energization interval.

[0369] When the multiple electrodes are energized one by one, the distance between adjacent positive electrodes is determined, while the flow rate of the target droplet is adjustable. If the energization interval of the multiple electrodes does not match the droplet flow rate, it is easy to break the droplet or prevent the droplet from deflecting to the target side. Determining the energization interval of the electrodes according to the flow rate of the target droplet can make the droplet flow rate match the energization interval, improving the efficiency and effect of the electrode assembly in pulling the target droplet to the target side.

[0370] Optionally, as shown in Figure 22 step S300 controls the multiple positive electrodes of the electrode assembly of the droplet sorting system to be energized one by one starting from the first moment, including:

[0371] S321, the droplet sorting system determines the target voltage of the multiple electrodes according to the flow rate of the target droplet.

[0372] S322, the droplet sorting system controls the multiple electrodes of the electrode assembly to be energized one by one starting from the first moment according to the determined energization voltage.

[0373] When the flow rate of the target droplet is relatively fast, the time duration for passing through the working area of the electrode assembly is shorter. In order to deflect the target droplet within a shorter time duration, the electrode assembly requires a larger voltage to apply a larger electrophoretic force to the target droplet. When the flow rate of the target droplet is relatively slow, the time duration for passing through the working area of the electrode assembly is longer. In order to avoid breaking the droplet due to excessive electrophoretic force, the electrode assembly requires a smaller voltage.

[0374] Optionally, as shown in Figure 24 before step S31 where the droplet sorting system applies a laser to the droplet to make the fluorescent marker combined with the magnetic particles in the droplet emit light, the droplet sorting method further includes:

[0375] S21, the droplet sorting system applies a magnetic field to the droplet to pull the agglomerated magnetic particles into a linear shape.

[0376] As shown in Figure 11 When the droplet without pre-magnetization enters the first magnetic field, the particle clusters are pulled into multiple thin lines. This can make the distribution of the magnetic particles in the droplet have a certain directionality, which is beneficial for the droplet sorting system to accurately identify the target droplet.

[0377] Optionally, in combination with Figure 24 As shown, before the droplet sorting system applies a magnetic field to the droplets in step S21 to pull the agglomerated magnetic particles into a line, the method further includes:

[0378] S11, the droplet sorting system pre-magnetizes the droplets to cause the magnetic particles in the droplets to agglomerate.

[0379] In combination with Figure 9 As shown, the distribution of the non-pre-magnetized magnetic particles and particle clusters is relatively dispersed; in combination with Figure 10 As shown, the distribution of the pre-magnetized magnetic particles and particle clusters is in an agglomerated state.

[0380] In combination with Figure 12 As shown, after the pre-magnetized droplets enter the first magnetic field, the particle clusters are pulled into a thick line.

[0381] In combination with Figure 13 As shown, Figure 13 In, the left peak is the fluorescence intensity characteristic peak after the non-pre-magnetized droplets enter the first magnetic field, and the right peak is the fluorescence signal characteristic peak after the pre-magnetized droplets enter the first magnetic field. It can be seen that the characteristic peak is more obvious after the pre-magnetized droplets enter the first magnetic field, which is beneficial to the fluorescence signal recognition of the droplets.

[0382] In the embodiments of the present disclosure, pre-magnetizing the droplets to cause the magnetic particles in the droplets to agglomerate can be performed by the pre-magnetizing component of the fluorescence signal enhancement device in the above embodiments, or it can be that a magnetic field is applied to the droplets after incubation is completed so that the magnetic particles are magnetized and agglomerated. Since the incubation has ended, magnetizing the magnetic particles will not affect the incubation effect.

[0383] In the embodiments of the present disclosure, applying a magnetic field to the droplets can be completed in the above-mentioned flow channel assembly, or it can be completed in other forms of flow sorting devices. Pulling the particle clusters composed of magnetic particles into a line can improve the accuracy of fluorescence recognition of the droplets.

[0384] Using the droplet sorting method provided by the embodiments of the present disclosure, the pre-magnetizing component can magnetize the magnetic particles before entering the first magnetic field to form an agglomerated state. The magnetized and agglomerated magnetic particles can be better pulled into a line after entering the magnetic field, so that the fluorescent substances in the particle clusters can be more fully excited by the laser, thereby improving the recognition accuracy of the droplets.

[0385] Optionally, applying a deflection force to the target droplet to deflect the end of the target droplet to the target flow channel includes: the droplet sorting system sequentially activates a plurality of electrodes arranged along the droplet flow direction to apply an electrophoresis force to the target droplet multiple times to deflect the target droplet to the target flow channel.

[0386] The sorting device includes a positive electrode and a negative electrode. The number of positive electrodes is multiple, and the multiple positive electrodes are arranged at intervals along the direction of the droplet flow channel on one side of the droplet flow channel. When the multiple positive electrodes are activated successively, a deflection force is applied to the target droplet multiple times, so that the target droplet is deflected to the target flow channel, which is also the first liquid outlet flow channel mentioned above.

[0387] With such a setting form, the electrophoresis force acts on the droplet for a longer time, and the droplet can be better deflected to the target flow channel.

[0388] Optionally, the target flow channel is connected to a first air pump. Applying a deflection force to the target droplet to deflect the end of the target droplet to the target flow channel includes: starting the first air pump to apply positive pressure to the target flow channel when a non-target droplet is about to enter the target flow channel, so that the non-target droplet is deflected to the non-target flow channel.

[0389] When the first air pump works, it applies positive pressure to the first liquid outlet flow channel. In this way, a certain pressure difference is generated between the first liquid outlet flow channel and the second liquid outlet flow channel. When the non-target droplet flows through the liquid outlet section of the droplet flow channel, it is deflected to the second liquid outlet flow channel under the action of the pressure difference. The response speed of the air pump is relatively fast, and high-speed sorting of droplets can be achieved. In addition, when positive pressure is applied to the first liquid outlet flow channel by the air pump, the force on the droplet is uniform, and the droplets in the droplet are not easily damaged.

[0390] Optionally, the non-target flow channel is connected to a second air pump. Applying a deflection force to the target droplet to deflect the end of the target droplet to the target flow channel includes: starting the second air pump to apply positive pressure to the non-target flow channel when the target droplet is about to enter the non-target flow channel, so that the target droplet is deflected to the target flow channel.

[0391] When the second air pump works, it applies positive pressure to the second liquid outlet flow channel. In this way, a certain pressure difference is generated between the first liquid outlet flow channel and the second liquid outlet flow channel. When the target droplet flows through the liquid outlet section of the droplet flow channel, it is deflected to the first liquid outlet flow channel under the action of the pressure difference. In this way, high-speed sorting of droplets can also be achieved, and the target droplet is not easily damaged when the target droplet is deflected.

[0392] Optionally, there are multiple antibodies in the droplet that specifically bind to magnetic particles, multiple antigens that specifically bind to the antibodies, and multiple secondary antibodies that specifically bind to the antibodies. Both the antigen and the secondary antibody are fluorescently stained; among them, the droplet sorting system applies a laser to the droplet to make the fluorescent label combined with the magnetic particles in the droplet emit light, including: the droplet sorting system applies a first laser and a second laser to the linear magnetic particles to make the first fluorescent label and the second fluorescent label combined with the magnetic particles in the droplet emit light; the droplet sorting system marks the droplets that meet the fluorescence conditions as target droplets, including: marking the droplets whose first fluorescence signal meets the first condition and whose second fluorescence signal meets the second condition as target droplets.

[0393] After applying the first laser and the second laser to the droplet, the antibodies and antigens in the droplet are excited to emit the first fluorescence signal and the second fluorescence signal. If the intensities of both the first fluorescence signal and the second fluorescence signal meet the preset conditions, it is considered that there is a particle cluster in the droplet where magnetic particles, antibodies, antigens, and secondary antibodies are combined, and then the droplet is marked as a target droplet.

[0394] With such a setting form, the accuracy of droplet recognition can be further improved.

[0395] Optionally, the second condition is determined according to the first condition.

[0396] The numbers of magnetic particle antigens and secondary antibodies are different in different droplets. When there are fewer magnetic particles or antigens in the particle cluster, it is considered that the corresponding antibody quantity is less. Therefore, setting a correspondingly lower second condition for the second fluorescence signal when the first fluorescence signal is weak is conducive to identifying more samples that meet the usage requirements.

[0397] Optionally, in combination Figure 24 As shown, after marking the droplets whose first fluorescence signal meets the first condition and whose second fluorescence signal meets the second condition as target droplets, the droplet sorting method further includes:

[0398] S61, the droplet sorting system obtains the first moment when the target droplet flows through the imaging position.

[0399] S71, the droplet sorting system activates the imaging component at the first moment to obtain an image of the target droplet.

[0400] With such a setting form, an image of the target droplet can also be obtained during the process of sorting droplets, which is not only conducive to users analyzing and researching the samples in the target droplets based on the images of the target droplets, but also convenient for users to adjust parameters such as the pre-magnetization magnetic field intensity, the first magnetic field intensity, and the droplet flow rate of the droplet sorting system according to the obtained images.

[0401] Optionally, in combination Figure 24 As shown, after calculating the first moment when the target droplet flows through the imaging position, the droplet sorting method further includes:

[0402] S81, the droplet sorting system activates the light source component at the first moment to supplement light for the imaging component.

[0403] The light source component is only activated at the first moment, which can reduce the light pollution of the light source component and increase the service life of the light source component.

[0404] In combination Figure 25 As shown, an embodiment of the present disclosure provides a fluorescence signal detection method for enhancing the fluorescence signal of droplets, including:

[0405] S01, the fluorescence signal detection device pre-magnetizes the droplet to agglomerate the magnetic particles in the droplet.

[0406] S02, the fluorescence signal detection device applies a magnetic field to the droplet to pull the agglomerated magnetic particles into a line.

[0407] S03, the fluorescence signal detection device applies a laser to the droplet to cause the fluorescent labels combined with the magnetic particles in the droplet to emit light.

[0408] S04, the fluorescence signal detection device detects the fluorescence signal of the fluorescent labels in the droplet.

[0409] Exemplarily, the droplet includes at least one cell, a plurality of magnetic particles, a plurality of antibodies specifically binding to the magnetic particles, a plurality of antigens specifically binding to the antibodies, and / or secondary antibodies, and at least one of the antigen and / or secondary antibody is fluorescently stained.

[0410] In the embodiments of the present disclosure, pre-magnetizing the droplet to agglomerate the magnetic particles in the droplet can be performed by the pre-magnetizing component of the fluorescence signal enhancement device in the above embodiments, or can be that after applying a magnetic field to the droplet after incubation is completed, the magnetic particles are magnetized and agglomerated. Since the incubation has ended, magnetizing the magnetic particles will not affect the incubation effect.

[0411] In the embodiments of the present disclosure, applying a magnetic field to the droplet can be completed in the above-mentioned flow channel component, or can be completed in other forms of flow sorting devices. Pulling the particle clusters composed of magnetic particles into a line in any sorting form can improve the accuracy of fluorescence recognition of the droplet.

[0412] The fluorescence signal detection method provided by the embodiments of the present disclosure can be implemented based on the above-mentioned fluorescence signal enhancement device, fluorescence signal detection device, or droplet observation device.

[0413] After pre-magnetizing the droplet, the magnetic particles in the droplet are magnetized and agglomerated. The agglomerated magnetic particles are pulled into a line in the first magnetic field. Since the magnetic particles are in a line, the antigen and / or secondary antibody bound to the magnetic particles are also distributed in a line. After applying a laser to the linear magnetic particles, the antigen and / or secondary antibody can be more fully excited. When detecting the fluorescence signal of the fluorescent label, the fluorescence signal has obvious characteristic peaks. In this way, it can be more accurately determined whether the droplet contains the target droplet through the characteristic peaks of the antigen and / or secondary antibody.

[0414] Using the droplet sorting method provided by the embodiments of the present disclosure, the pre-magnetizing component can magnetize the magnetic particles before entering the first magnetic field to form an agglomerated state. The magnetized and agglomerated magnetic particles can be better pulled into a line after entering the magnetic field, so that the fluorescent substances in the particle cluster can be more fully excited by the laser, thereby improving the recognition accuracy of the droplet.

[0415] Optionally, pre-magnetizing the droplets to agglomerate the magnetic particles in the droplets includes: applying a pre-magnetizing magnetic field to the magnetic particles to magnetize the magnetic particles in the droplets; and changing the direction and / or intensity of the pre-magnetizing magnetic field multiple times to cause the magnetized magnetic particles in the droplets to agglomerate.

[0416] The magnetic particles in the droplets are not only magnetized in the pre-magnetizing magnetic field, but also rotate and move under the action of magnetic force to agglomerate. The magnetic particles can be magnetized in a relatively short time, but it takes more time to agglomerate. When the direction of the pre-magnetizing magnetic field changes, the movement of the magnetic particles in the magnetic field will be intensified, thus accelerating the agglomeration of the magnetic particles. By using such a method, the agglomeration effect of the magnetic particles in the droplets in the pre-magnetizing magnetic field can be improved.

[0417] Optionally, changing the direction of the pre-magnetizing magnetic field multiple times includes: controlling the direction of the pre-magnetizing magnetic field to change with time; or, changing the angle of the droplets in the pre-magnetizing magnetic field multiple times.

[0418] As an implementation, the pre-magnetizing magnet includes an alternating current electromagnet. When the pre-magnetizing magnet is energized, a circumferential magnetic field is generated. As another implementation, when the droplets flow in the pre-magnetizing magnetic field, a flow path with a changing direction is formed. This is beneficial to the movement of the magnetic particles in the droplets in the pre-magnetizing magnetic field to cause agglomeration.

[0419] Optionally, changing the intensity of the pre-magnetizing magnetic field multiple times includes: controlling the intensity of the pre-magnetizing magnetic field to change with time; or, changing the position of the droplets in the pre-magnetizing magnetic field multiple times.

[0420] As an implementation form, the pre-magnetizing magnet includes an electromagnet, and the intensity of the pre-magnetizing magnetic field is changed by changing the current intensity of the electromagnet. As another implementation, when the droplets flow in the pre-magnetizing magnetic field, they are at different positions in the pre-magnetizing magnetic field, so that the magnetic field intensity acting on the droplets changes. This is beneficial to the movement of the magnetic particles in the droplets in the pre-magnetizing magnetic field to cause agglomeration.

[0421] Combined Figure 26 As shown in the figure, an embodiment of the present disclosure provides a device for controlling a droplet sorting system, including a processor 900 (processor) and a memory 901. Optionally, the device may further include a communication interface 902 (Communication Interface) and a bus 903. Among them, the processor, the communication interface, and the memory can complete communication with each other through the bus. The communication interface can be used for information transmission. The processor can call the logical instructions in the memory to execute the droplet sorting method of the above embodiment.

[0422] In addition, when the logical instructions in the above-mentioned memory are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium.

[0423] As a computer-readable storage medium, the memory can be used to store software programs and computer-executable programs, such as the program instructions / modules corresponding to the methods in the embodiments of the present disclosure. The processor executes functional applications and data processing by running the program instructions / modules stored in the memory, that is, implements the droplet sorting method in the above embodiments.

[0424] The memory may include a program storage area and a data storage area. Among them, the program storage area can store an operating system and application programs required for at least one function; the data storage area can store data created according to the use of the terminal device, etc. In addition, the memory may include high-speed random access memory and may also include non-volatile memory.

[0425] The embodiments of the present disclosure provide a droplet sorting system, including: a droplet sorting system body and the above-mentioned device for controlling the droplet sorting system. The device for controlling the droplet sorting system is installed on the product body. The installation relationship described here is not limited to being placed inside the product, but also includes installation connections with other components of the product, including but not limited to physical connections, electrical connections, or signal transmission connections, etc. Those skilled in the art can understand that the device for controlling the droplet sorting system can be adapted to a feasible product body, thereby implementing other feasible embodiments.

[0426] The embodiments of the present disclosure provide a computer-readable storage medium storing computer-executable instructions, and the computer-executable instructions are set to execute the above-mentioned droplet sorting method.

[0427] The above-mentioned computer-readable storage medium can be a transient computer-readable storage medium or a non-transient computer-readable storage medium.

[0428] The technical solutions of the embodiments of the present disclosure can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes one or more instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in the embodiments of the present disclosure. The foregoing storage medium can be a non-transient storage medium, including: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes, or can also be a transient storage medium.

[0429] The above description and the accompanying drawings fully illustrate the embodiments of the present disclosure, enabling those skilled in the art to practice them. Other embodiments may include structural, logical, electrical, process, and other changes. The embodiments merely represent possible variations. Unless explicitly required, individual components and functions are optional, and the order of operations may vary. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. Moreover, the terms used in this application are only for describing the embodiments and do not limit the claims. As used in the description of the embodiments and the claims, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are intended to also include the plural forms. Similarly, as used in this application, the term "and / or" refers to any and all possible combinations including one or more of the associated listed items. Additionally, when used in this application, the term "comprise" and its variants "comprises" and / or "comprising" etc. mean the presence of the stated features, wholes, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or groups of these. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, or apparatus comprising the element. Herein, each embodiment may focus on the differences from other embodiments, and the same or similar parts among the embodiments may be referred to each other. For the methods, products, etc. disclosed in the embodiments, if they correspond to the method part disclosed in the embodiments, the relevant parts may refer to the description of the method part.

[0430] Those skilled in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed in a hardware or software manner may depend on the specific application and design constraints of the technical solution. The skilled person may use different methods for each specific application to implement the described functions, but such implementation should not be considered to exceed the scope of the embodiments of the present disclosure. The skilled person can clearly understand that for the convenience and brevity of description, the specific working processes of the systems, devices, and units described above can refer to the corresponding processes in the foregoing method embodiments and will not be elaborated herein.

[0431] In the embodiments disclosed in this document, the disclosed methods, products (including but not limited to devices, equipment, etc.) can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units can be merely a logical function division. In actual implementation, there can be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Additionally, the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces. The indirect coupling or communication connection of devices or units can be in electrical, mechanical, or other forms. The units described as separate components may or may not be physically separated. The components displayed as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to implement this embodiment. Additionally, in the embodiments of this disclosure, the various functional units can be integrated in one processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit.

[0432] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to embodiments of the present disclosure. In this regard, each block in the flowchart or block diagram can represent a module, a program segment, or a part of code that contains one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks can occur in a different order than that marked in the accompanying drawings. For example, two consecutive blocks can actually be executed substantially in parallel, and they can sometimes be executed in the reverse order, depending on the functions involved. In the descriptions corresponding to the flowcharts and block diagrams in the accompanying drawings, the operations or steps corresponding to different blocks can also occur in a different order than that disclosed in the description. Sometimes, there is no specific order between different operations or steps. For example, two consecutive operations or steps can actually be executed substantially in parallel, and they can sometimes be executed in the reverse order, depending on the functions involved. Each block in the block diagram and / or flowchart, as well as the combination of blocks in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system for performing the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

Claims

1. A droplet sorting system, characterized in that, Comprising: A flow channel assembly defining a droplet flow channel, a first liquid outlet flow channel, and a second liquid outlet flow channel for the flow of droplets; A fluorescence signal detection device for exciting droplets to emit fluorescence and marking droplets that meet the fluorescence condition as target droplets; A sorting device provided corresponding to the liquid outlet section of the droplet flow channel. The target droplets flowing through the liquid outlet section of the droplet flow channel enter the first liquid outlet flow channel under the deflection action of the sorting device, and the non-target droplets enter the second liquid outlet flow channel.

2. The droplet sorting system according to claim 1, wherein The sorting device includes: A sorting electromagnet provided at the liquid outlet section of the droplet flow channel. The sorting electromagnet is activated when the target droplets flow through the liquid outlet section of the droplet flow channel so that the target droplets are deflected to the first liquid outlet flow channel under the action of the magnetic force.

3. The droplet sorting system according to claim 1, characterized in that The sorting device includes: A first air pump provided in the first liquid outlet flow channel. The first air pump is configured to apply a positive pressure to the first liquid outlet flow channel when the non-target droplets flow through the liquid outlet section of the droplet flow channel.

4. The droplet sorting system according to claim 1, wherein The sorting device includes: A second air pump provided in the second liquid outlet flow channel. The second air pump is configured to apply a positive pressure to the second liquid outlet flow channel when the target droplets flow through the sorting device.

5. The droplet sorting system according to any one of claims 1 to 4, characterized in that The sorting device further includes: A positive electrode provided on one side of the droplet flow channel; A negative electrode provided on the same side of the droplet flow channel as the positive electrode. When the positive electrode and the negative electrode are energized, an electric field acting on the liquid outlet section of the droplet flow channel is formed, and the target droplets are deflected to the first liquid outlet flow channel under the action of the electrophoresis force.

6. The droplet sorting system according to claim 5, wherein The sorting device includes a plurality of positive electrodes and a plurality of negative electrodes. The plurality of positive electrodes and the plurality of negative electrodes are alternately arranged, and the plurality of negative electrodes are connected to each other.

7. The droplet sorting system according to claim 5, wherein The sorting device includes a plurality of positive electrodes and two negative electrodes. The two negative electrodes are respectively located on both sides of the plurality of positive electrodes.

8. The droplet sorting system according to claim 5, wherein The sorting device includes a plurality of positive electrodes. The distances between the plurality of positive electrodes and the droplet flow channel are not completely the same, or the plurality of positive electrodes are sequentially activated when the target droplets flow through the liquid outlet section of the droplet flow channel.

9. The droplet sorting system according to any one of claims 1 to 4, characterized in that The sorting device further includes: An electrode assembly including at least one electrode unit. The electrode unit is provided on one side of the droplet flow channel; Wherein, the electrode unit includes: One or more positive electrodes; Two negative electrodes respectively located on both sides of the one or more positive electrodes.

10. The droplet sorting system according to claim 9, wherein Along the droplet flow direction, the distances between the plurality of positive electrodes and the droplet flow channel gradually increase; and / or Along the droplet flow direction, the voltages of the plurality of positive electrodes gradually decrease.

11. The droplet sorting system according to claim 9, wherein The electrode assembly includes a plurality of electrode units, and the plurality of electrode units are arranged on the first side of the droplet flow channel.

12. The droplet sorting system according to claim 11, wherein Two adjacent electrode units share one negative electrode.

13. The droplet sorting system according to claim 9, wherein The positive electrode and / or the negative electrode are connected to a power source through a high-voltage isolation pulse transformer.

14. The droplet sorting system according to any one of claims 1 to 4, characterized in that, The flow channel assembly includes: A microfluidic chip that defines the droplet flow channel, the first liquid outlet flow channel, and the second liquid outlet flow channel inside.

15. The droplet sorting system according to claim 14, wherein, The microfluidic chip further defines a sheath liquid inlet flow channel and a sample liquid inlet flow channel. The liquid inlet end of the sample liquid inlet flow channel is used to fill droplets that have passed through a pre-magnetizing magnetic field. The liquid outlet end of the sample liquid inlet flow channel and the liquid outlet end of the sheath liquid inlet flow channel are connected to the liquid inlet end of the droplet flow channel. The droplets that have passed through the pre-magnetizing magnetic field are mixed with the sheath liquid and then enter the droplet flow channel.

16. The droplet sorting system according to claim 15, wherein, The microfluidic chip further defines a positive electrode flow channel and a negative electrode flow channel. A conductive medium is filled in the positive electrode flow channel to form a positive electrode, and / or a conductive medium is filled in the negative electrode flow channel to form a negative electrode.

17. The droplet sorting system according to claim 16, wherein, The material of the conductive medium is metal, and the metal conductive medium is filled in the electrode flow channel in a liquid state.

18. The droplet sorting system according to claim 14, wherein The flow channel assembly further includes: A support frame including a bottom plate, a first side plate, and a second side plate, with the first side plate and the second side plate disposed opposite to each other; Wherein, the microfluidic chip is located between the first side plate and the second side plate and is lapped on the upward-facing surface of the bottom plate.

19. The droplet sorting system according to claim 18, wherein The sorting device further includes: An electrode mounting plate fixed to the first side plate and / or the second side plate of the support frame; A positive electrode connecting member fixed to the electrode mounting plate and extending towards the microfluidic chip, and the positive electrode connecting member is used to connect the positive electrode to a power source; A negative electrode connecting member fixed to the electrode mounting plate and extending towards the microfluidic chip, and the negative electrode connecting member is used to connect the negative electrode to a power source.

20. The droplet sorting system according to any one of claims 1 to 4, characterized in that The fluorescence signal detection device includes: A laser assembly for emitting laser light to magnetic particles drawn into a line shape, and a fluorescent marker in the droplet is excited by the laser light to emit fluorescence; A fluorescence detection assembly for detecting the fluorescence emitted by the fluorescent marker in the droplet.

21. The droplet sorting system according to claim 20, wherein, The laser assembly includes: A first laser light source for emitting laser light of a first wavelength, and when one of the antigen and the secondary antibody is excited by the laser light of the first wavelength, it emits fluorescence of the first wavelength; The fluorescence detection assembly includes: A first fluorescence detector for detecting fluorescence of the first wavelength.

22. The droplet sorting system according to claim 21, wherein, The laser assembly further includes: A second laser light source for emitting laser light of a second wavelength, and when the other of the antigen and the secondary antibody is excited by the laser light of the second wavelength, it emits fluorescence of the second wavelength; The fluorescence detection assembly further includes: A second fluorescence detector for detecting fluorescence of the second wavelength.

23. The droplet sorting system according to claim 22, wherein The laser assembly further includes: A coaxial system for guiding a laser of a first wavelength and a laser of a second wavelength to droplets in a droplet flow channel, and the coaxial system is further configured to guide fluorescence of the first wavelength and fluorescence of the second wavelength in the droplet flow channel to a first fluorescence detector and a second fluorescence detector.

24. The droplet sorting system according to any one of claims 1 to 4, characterized in that, The fluorescence signal detection device includes: A light source assembly with a light emitting direction towards the droplets in the first magnetic field; An imaging assembly with an imaging position towards the droplets in the first magnetic field.

25. The droplet sorting system according to claim 24, wherein The imaging assembly includes: A high-speed camera with a lens towards the droplets in the first magnetic field, and the shutter of the high-speed camera is opened synchronously with the light source assembly.

26. The droplet sorting system according to any one of claims 1 to 4, characterized in that, It further includes: A fluorescence signal enhancement device for enhancing the fluorescence signal of magnetic particles in the droplets.

27. The droplet sorting system according to claim 26, wherein The fluorescence signal enhancement device includes: A magnet assembly for generating a first magnetic field, and the magnetic particles in the droplets are drawn into a line in the first magnetic field.

28. The droplet sorting system according to claim 27, wherein, It further includes: A pre-magnetization assembly for generating a pre-magnetization magnetic field, and the magnetic particles in the droplets are magnetized and agglomerated in the pre-magnetization magnetic field, and the agglomerated magnetic particles are drawn into a line in the first magnetic field.

29. The droplet sorting system according to claim 28, wherein The magnetic field intensity of the pre-magnetization magnetic field is greater than the magnetic field intensity of the first magnetic field.

30. The droplet sorting system according to claim 28, wherein, The pre-magnetization assembly includes: A pre-magnetization pipeline defining a pre-magnetization flow channel for the droplets to flow through; A pre-magnetization magnet for generating the pre-magnetization magnetic field, and at least a part of the pre-magnetization flow channel is located in the pre-magnetization magnetic field.

31. The droplet sorting system according to claim 30, wherein The pre-magnetization flow channel is connected to the droplet flow channel, and the droplet flow channel is located at the downstream of the pre-magnetization flow channel along the droplet flow direction.

32. The droplet sorting system according to claim 30, characterized in that, The pre-magnetization magnet includes: A first pre-magnetization magnet disposed on one side of the pre-magnetization pipeline; A second pre-magnetization magnet disposed on the other side of the pre-magnetization pipeline.

33. The droplet sorting system according to claim 30, wherein, The pre-magnetization magnet includes: A pre-magnetization coil wound around the pre-magnetization pipeline, the axis of the pre-magnetization coil is along the length direction of the pre-magnetization pipeline, and the pre-magnetization magnetic field is generated when the coil is energized.

34. The droplet sorting system according to claim 30, wherein The pre-magnetization magnet is used to generate a pre-magnetization magnetic field with a changing direction, and the magnetic particles in the droplets move and agglomerate under the action of the changing magnetic field force when in the pre-magnetization flow channel.

35. The droplet sorting system according to claim 34, wherein The pre-magnetization magnet includes a plurality of magnet pairs disposed close to the pre-magnetization flow channel, magnetic induction lines are formed between each magnet pair, and the magnetic induction line directions of the plurality of magnet pairs are different to form the pre-magnetization magnetic field with a changing direction.

36. The droplet sorting system according to claim 34, wherein The pre-magnetization magnet includes an electromagnet, and the pre-magnetization magnetic field with a changing direction is formed by adjusting the current intensity and / or current direction of the electromagnet; or, The pre-magnetization magnet includes a coil wound around the pre-magnetization pipeline, the pre-magnetization magnetic field is generated when the coil is energized, and the pre-magnetization magnetic field with a changing direction is formed by adjusting the current intensity and / or current direction of the coil.

37. The droplet sorting system according to claim 30, wherein the pre-magnetized flow channel is a flow channel with a changing direction, at least a part of the flow channel with a changing direction is located in the pre-magnetized magnetic field, and the magnetic particles in the droplet move under the action of the first magnetic field when moving in the flow channel with a changing direction and agglomerate.

38. The droplet sorting system according to claim 37, wherein the pre-magnetized flow channel includes a plurality of bending segments, and the plurality of bending segments are connected end to end to form a pre-magnetized flow channel with a changing direction.

39. The droplet sorting system according to claim 38, wherein the pre-magnetized flow channel is a spiral flow channel.

40. The droplet sorting system according to claim 39, wherein the pre-magnetized pipeline is wound around the pre-magnetized magnet to form the flow channel with a changing direction.

41. The droplet sorting system according to claim 30, wherein the pre-magnetized magnetic field includes a first part and a second part, the magnetic field direction of the first part remains unchanged, and the magnetic field direction of the second part changes with time.

42. The droplet sorting system according to claim 41, wherein the pre-magnetized magnet includes an alternating current electromagnet, and the second part of the pre-magnetized magnetic field is formed when the alternating current electromagnet is energized.

43. The droplet sorting system according to claim 41, wherein the pre-magnetized magnet is a direct current electromagnet, and the first part of the pre-magnetized magnetic field is formed when the direct current electromagnet is energized.

44. The droplet sorting system according to claim 30, wherein the pre-magnetized pipeline is a flexible hose, and the length of the part of the pre-magnetized flow channel located in the pre-magnetized magnetic field is adjusted by moving the pre-magnetized pipeline.

Images