A system and method for the analytical detection of cell deformation properties within microdroplets

Abstract

The application relates to a system and method for analyzing and detecting cell deformation characteristics in microdroplets, belonging to the field of microfluidic technology. The system comprises a microscopic imaging module, a data processing module, a capillary microchannel, a sample injection pump and a collection device; the microchannel is placed above a microscope object platform, a coaxial microchannel is adopted, a cell suspension is introduced into an inner tube, a continuous phase fluid is introduced into an outer tube, cells are wrapped in the suspension, the size of the droplet and the number of wrapped cells are controlled by changing the flow ratio, an outlet is connected with the collection device, and the collection device is used for collecting the detected cells and waste liquid; the capillary microchannel realizes mechanical extrusion of the cells in the microdroplets. The data processing module is connected with a microscope camera and is used for identifying the size change of the cells and analyzing the deformation characteristics according to characteristic parameters. The application generates cells wrapped by droplets in the microchannel and makes the cells pass through a narrow contraction area, analyzes the influence of the contraction area on the deformation of the cells in the microdroplets, and can realize efficient and accurate detection of the deformation of the cells in the microdroplets.

Description

Technical Field

[0001] This invention belongs to the field of microfluidics technology and relates to an analytical detection system and method for the deformation characteristics of cells within microdroplets. Background Technology

[0002] In the field of biomedical detection research, cell deformability is a core indicator for assessing cell activity, physiological function, and pathological changes, and is of great significance for disease diagnosis, drug screening, and cell therapy. Microfluidic technology, with its unique advantages such as miniaturization, low reagent consumption, high throughput, and the ability to simulate the in vivo physiological environment, has become a core technology in the field of microscale cell detection.

[0003] During flow, the geometry of microchannels affects flow patterns and alters cell shape; strong geometric constraints can lead to cell deformation and potentially cell inactivation. Cell encapsulation technology encapsulates cells within droplets formed by suspensions. Microdroplets can encapsulate single or multiple cells, forming independent miniature detection units. This shell / core structure reduces the impact of the external environment on cell viability and avoids cell contamination, thereby improving cell activity and stability. Furthermore, this encapsulation method can be used to analyze internal cell interactions and is therefore widely applied in scenarios such as cell morphology observation and analysis.

[0004] Currently, many studies have explored the deformation of single cells during flow. Chinese patent CN113008766A discloses a dynamic behavior detection system for cancer cells based on microfluidic multiple compression. This system achieves continuous cell compression by setting multiple narrow channels in a microfluidic chip and identifies cancer cells using high-speed imaging and visual processing. However, research on the deformation characteristics of cells encapsulated by droplets is very limited. Microdroplets prevent cells from directly contacting the external environment, reducing cell deformation and preventing cell inactivation. This invention provides an analysis and detection system for the deformation characteristics of cells within microdroplets. By changing the continuous phase flow rate to generate droplets of different sizes, the deformation coefficient is used to analyze the cell deformation characteristics to select the optimal droplet size. Summary of the Invention

[0005] To analyze the morphological changes of cells within microdroplets, this invention provides an analytical system and method for detecting the deformability characteristics of cells within microdroplets. The system is designed to analyze morphological changes of cells encapsulated by droplets and detect the anisotropic dimensions of the cells; simultaneously, it analyzes the interactions between multiple cells within the microdroplet. By changing parameters such as the microdroplet diameter, the optimal microdroplet size can be selected.

[0006] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: An analytical detection system for the deformation characteristics of cells within microdroplets is disclosed. This system detects the effect of contraction channels on cell deformation, clarifies the protective function of the droplets, and selects droplets of optimal size. The system includes a microscopic imaging module 1, a data processing module 2, a capillary microchannel 3, a sample injection pump 4, a collection device 5, an inner inlet tube 6, an outer inlet tube 7, a compression tube 8, and a recovery tube 9. The microscopic imaging module 1 includes a microscope and its camera for observing the morphological changes of cells within the microdroplets. The data processing module 2 is connected to the camera to receive images acquired by the camera, measure cell size, and determine the optimal droplet size based on the deformation coefficient. The deformation characteristics of cells are analyzed. The capillary microchannel 3 is placed on the microscope stage, with its inlet connected to the injection pump 4 and its outlet connected to the collection device 5. The injection pump 4 includes a continuous phase injection pump and a cell suspension injection pump, used to inject cell suspension and continuous phase fluid into the capillary microchannel 3 and control the flow rate, so that the cells are encapsulated in droplets. The collection device 5 adopts a sealed design and is connected to the outlet of the capillary microchannel 3 to collect the cells and waste liquid after detection. The microscope and camera acquire images of microdroplets and cells flowing through the capillary microchannel 3.

[0007] The capillary microchannel 3 includes an inner inlet tube 6, an outer inlet tube 7, a compression tube 8, and a recovery tube 9, all four tubes being coaxially mounted. Specifically: The inner inlet tube 6 extends into the outer inlet tube 7 from the left end, and the two are coaxially mounted. The left port of the inner inlet tube 6 is outside the outer inlet tube 7 and is connected to a cell suspension injection pump for introducing cell suspension into the inner inlet tube 6. The left port of the outer inlet tube 7 is connected to a continuous phase injection pump for introducing continuous phase between the outer wall of the inner inlet tube 6 and the inner wall of the outer inlet tube 7. The compression tube 8 is inserted into the outer inlet tube 7 from the right end, and the two are coaxially mounted. The right port of the compression tube 8 is inserted into the recovery tube 9, and the two are coaxially mounted. The right side of the recovery tube 9 is connected to the collection device 5.

[0008] Cell suspension and continuous phase are introduced through the inner inlet tube 6 and the outer inlet tube 7. After the two phases are mixed at the right end of the outer inlet tube 7, they enter the compression tube 8 and flow into the recovery tube 9. The compression tube 8 realizes the mechanical deformation of cells within the microdroplets. The recovery tube 9 is used to restore the mechanical deformation of cells.

[0009] Furthermore, the inner diameter of the inlet inner tube 6 is 10-30 μm, and the wall thickness is 3-5 μm. The inner diameter of the inlet outer tube 7 is 50-80 μm, and the wall thickness is 5-8 μm. The inner diameter of the compression tube 8 is 10-65 μm, and the wall thickness is 3-6 μm. The inner diameter of the recovery tube 9 is 50-80 μm, and the wall thickness is 5-8 μm. The inner diameter of the recovery tube 9 is larger than the outer diameter of the compression tube 8, the outer diameter of the compression tube 8 is smaller than that of the inlet outer tube 7, and the inner diameter of the compression tube 8 is larger than the inner diameter of the inlet inner tube 6.

[0010] Furthermore, the length of the inner inlet tube 6 is 400-500 μm; the length of the outer inlet tube 7 is 1000-1200 μm; the length of the recovery tube 9 is 600-1000 μm; and the length of the recovery tube 8 is 300-500 μm. The inner inlet tube 6 is inserted into the outer inlet tube 7 to a depth of 300-350 μm; the compression tube 8 is inserted into the outer inlet tube 7 and the recovery tube 9 to the same depth, which is 50-100 μm.

[0011] Furthermore, the inner diameter of the inlet tube 7 and the recovery tube 9 in the capillary microchannel 3 is larger than the diameter of the microdroplet, and the inner diameter of the compression tube 8 in the capillary microchannel 3 is smaller than the diameter of the microdroplet.

[0012] Furthermore, the capillary microchannel 3 is made of materials including glass, polymer, and metal.

[0013] Furthermore, the continuous phase is silicone oil, and the cell suspension is used to culture cells in a suspension, the cells being human red blood cells and cancer cells, and the suspension being a polyethylene glycol solution or a phosphate buffer solution.

[0014] Furthermore, the flow rate of the continuous phase is 100-400 μL·min. -1 The flow rate of the cell suspension is 10-100 μL·min. -1 .

[0015] Furthermore, the data processing module 2 can process the images captured by the camera, extract the axial and radial diameters of the deformed cells, calculate the cell deformation coefficient, and generate an analysis report.

[0016] Furthermore, the inlet of the capillary microchannel 3 is connected to the injection pump 4, and the outlet of the capillary microchannel 3 is connected to the collection device 5 through sterile rigid tubes. The inner diameter of the tubes matches the inner diameter of the inlet and outlet of the capillary microchannel 3 to ensure the sealing and stability of the fluid transport.

[0017] Furthermore, the compression ratio in the capillary microchannel 3 can be changed according to actual needs, wherein the compression ratio is the ratio of the inner diameter of the compression tube 8 to the inner diameter of the inlet outer tube 7. The range of the compression ratio is between 1 / 4 and 3 / 4.

[0018] Furthermore, the detection system can detect droplets with different numbers of cells depending on actual needs. When the droplet size is small, each droplet contains only one cell. Adjusting the continuous phase flow rate can make each droplet contain two or more cells, and the mutual compression phenomenon between cells can be observed.

[0019] Furthermore, the injection pump 4 can be adjusted to different flow rates to change the flow ratio between the cell suspension and the continuous phase, thereby generating microdroplets of different sizes to meet the detection needs of cells of different sizes.

[0020] Furthermore, the camera can perform noise reduction and sharpening processing on the acquired images, effectively improving image quality in low-light and high-speed acquisition scenarios, clearly capturing subtle features of cell deformation, and providing clearer and more accurate images for cell contour extraction and deformation coefficient calculation in data processing module 2.

[0021] An analytical method for detecting cell deformability characteristics within microdroplets, implemented based on the aforementioned system, includes the following steps: Step 1: Place the inlet outer tube 7 in the center of the substrate and fix the reference position with glue. After the inlet outer tube 7 is fixed, insert the inlet inner tube 6 and the compression tube 8 from the left side of the inlet outer tube 7 and insert the compression tube 8 from the right side of the inlet outer tube 7. Observe the coaxiality of the capillary microchannel 3 under a microscope and fix it simply with glue. After the compression tube 8 is fixed, insert the recovery tube 9 on the right side of the compression tube 8. Observe under a microscope to ensure the coaxiality of all capillaries and fix the position of the capillaries with glue.

[0022] Furthermore, the substrate material includes glass, polymer, or metal.

[0023] Step 2: Connect the inlet of the capillary microchannel 3 to the injection pump 4 and the outlet to the collection device 5, and seal the connection to ensure that all connections are sealed and leak-free. The preparation of the capillary microchannel 3 is now complete.

[0024] Step 3: Adjust the microscope position so that the lens is aligned with the compression tube 8 of the capillary microchannel 3; turn on the power to the microscope, data processing module 2, injection pump 4 and collection device 5, check the connection status of each component, and ensure that the signal connection of data processing module 2 is normal.

[0025] Step 4: After the detection device is set up, the continuous phase fluid is first introduced through the inlet outer tube 7. After the inlet outer tube 7 is filled with the continuous phase fluid, the cell suspension injection pump is started to introduce the cell suspension through the inlet inner tube 6. When the flow pattern is stable, the deformation and recovery process of red blood cells under the action of flow field and shear are recorded. The image is imported into the data processing module 2 to calculate the cell deformation coefficient to avoid human error.

[0026] Step 5: After the detection is completed, turn off the injection pump 4. After all the remaining liquid in the capillary microchannel 3 has flowed into the collection device 5, classify and process the samples in the collection device 5. For cell waste and damaged cells, pour them into the biological waste collection container. For cells with good activity, separate the microdroplets from the cells by aseptic centrifugation, collect the precipitated active cells, wash them with physiological saline, and they can be used for subsequent related experimental research. All sterile tubes and collection devices 5 that have come into contact with cells are disinfected by soaking in a solution containing 75% ethanol for 30 minutes. After disinfection, rinse them with sterile deionized water, air dry them, and store them properly to avoid cross-contamination.

[0027] Step 6: Plot the deformation coefficient of the cells at different positions in the compression tube 8 into images, analyze the effect of droplets of different sizes on the cell deformation coefficient, and select the optimal droplet size to protect the cells.

[0028] Furthermore, the criterion for judging cell deformation is the deformation coefficient. The calculation method is as follows: in, a The axial diameter of the cell, in μm; b Radial diameter of the cell, in μm. Deformation coefficient. Between -1 and 1, the closer to 0, the smaller the cell deformation.

[0029] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) In this invention, cells protected by microdroplets are squeezed through a narrow area, causing the cells to exhibit mechanical deformation behavior in response to the squeeze. The camera can clearly capture the changes in cell shape. After the flow pattern stabilizes, the changes in cells within the microdroplets are observed, and the flow rate of the syringe pump is adjusted in real time according to the changes in the cell images under the microscope to generate droplets of different sizes. The degree of cell deformation is analyzed using the deformation coefficient to select the optimal droplet size.

[0030] (2) The present invention can efficiently and accurately detect the deformation of cells within microdroplets, providing data support for the selection of droplet size in droplet-protected cells. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of an analytical detection system for the deformation characteristics of cells within microdroplets according to the present invention.

[0032] Figure 2 This is a schematic diagram illustrating the dynamic changes of microdroplets containing single cells within a capillary microchannel.

[0033] Figure 3 This is a schematic diagram showing the dynamic changes of microdroplets containing multiple cells in a capillary microchannel.

[0034] In the figure, 1 is the microscopic imaging module; 2 is the data processing module; 3 is the capillary microchannel; 4 is the injection pump; 5 is the collection device; 6 is the inlet inner tube; 7 is the inlet outer tube; 8 is the compression tube; and 9 is the recovery tube. Detailed Implementation

[0035] To enhance understanding and appreciation of the present invention, the technical solutions of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the examples shown herein are only a part of the examples of the present invention, used to explain the present invention, and do not represent all the examples, nor should they be considered as limitations on the present invention. Other embodiments obtained by those skilled in the art based on the embodiments provided by the present invention without creative effort are all within the scope of protection of the present invention.

[0036] Example 1 See Figure 1 and Figure 2 An analytical detection system for the deformation characteristics of cells within microdroplets, comprising a microscopic imaging module 1, a data processing module 2, a capillary microchannel 3, a sample injection pump 4, a collection device 5, an inner inlet tube 6, an outer inlet tube 7, a compression tube 8, and a recovery tube 9.

[0037] The microscopic imaging module 1 mounts the camera onto the microscope and connects to the data processing module 2 via a USB interface. The capillary microchannel 3 is placed on the microscope's platform, with its inlet connected to the injection pump 4 and its outlet connected to the collection device 5. The capillary microchannel 3 is made of glass capillaries and includes an inner inlet tube 6, an outer inlet tube 7, a compression tube 8, and a recovery tube 9. The inner inlet tube 6 carries the cell suspension; the outer inlet tube 7 carries a continuous phase fluid, encapsulating the cells in the suspension and allowing them to fully develop before entering the compression tube 8; the compression tube 8 is used to achieve mechanical deformation of the cells within the microdroplets; and the recovery tube 9 is used to restore the mechanical deformation of the cells. The data processing module 2 is connected to the camera and is used to receive and process image data, measure cell size, and analyze cell deformation characteristics based on the deformation coefficient.

[0038] In this embodiment, human peripheral blood erythrocytes are used as the detection object. By detecting the behavior of individual cells within the droplet, the protective effect of the droplet on the cells is determined, and the protective droplet of the optimal size is selected.

[0039] Step 1: Fabricate capillary microchannels 3. Select capillary microchannels 3 with a compression ratio of 1 / 3, where the compression ratio is the ratio of the inner diameter of the compression tube 8 to the inner diameter of the inlet outer tube 7. Specifically, the inner diameter of the inlet inner tube 6 is 22 μm, the outer diameter is 31 μm, and the length is 400 μm, ensuring cells can enter the capillary microchannel 3; the inner diameter of the inlet outer tube 7 is 75 μm, the outer diameter is 90 μm, and the cells are encapsulated in the suspension by adding a continuous phase; its length is 1000 μm; the inner diameter of the compression tube 8 is 25 μm, the outer diameter is 35 μm, and the length is 800 μm; the inner diameter of the recovery tube 9 is 75 μm, the outer diameter is 90 μm, and the length is 400 μm.

[0040] First, the inlet outer tube 7 is placed at the center of the substrate and fixed with glue to determine the reference position of the entire capillary microchannel 3. Then, the inlet inner tube 6 and the compression tube 8 are inserted into the inlet outer tube 7 from the left and right sides respectively. The coaxiality of each capillary is calibrated under a microscope and initially fixed with glue. Next, the recovery tube 9 is inserted to the right of the compression tube 8, and the overall coaxial alignment is ensured again by microscopic calibration. Finally, glue is used to complete the final fixation. The inlet inner tube 6 is inserted into the inlet outer tube 7 to a depth of 300 μm; the compression tube 8 is inserted into the inlet outer tube 7 and the recovery tube 9 to the same depth, 100 μm. Then, the capillary microchannel 3 and all connections of the tubing are sealed with glue and left to stand for 48 hours to allow the glue to cure before use.

[0041] Step 2: Connect the inlet of the capillary microchannel 3 to the injection pump 4 and the outlet to the collection device 5, and seal the connection to ensure that all connections are sealed and leak-free. The preparation of the capillary microchannel 3 is now complete.

[0042] Step 3: Adjust the microscope position so that the lens is aligned with the compression tube 8 of the capillary microchannel 3; turn on the power to the microscope, data processing module 2, injection pump 4 and collection device 5, check the connection status of each component, and ensure that the signal connection of data processing module 2 is normal.

[0043] Step 4: After the detection device is assembled, first introduce the continuous phase fluid into the capillary microchannel 3 through the inlet outer tube 7; after the channel is completely filled with the continuous phase, start the cell suspension injection pump. Use 20 μm diameter red blood cells as the detection cells, a 5% polyethylene glycol solution as the suspension phase, and a sample red blood cell concentration of 1 × 10⁻⁶. 6 Cells / mL were kept constant to ensure consistent initial cell viability. -1The continuous phase used was silicone oil. Microdroplets of different outer diameters were fabricated by adjusting the flow rate of the continuous phase, with the droplet diameter controlled between 25-50 μm to ensure that most microdroplets contained a single red blood cell. Droplets containing mononuclear red blood cells were observed, while other results were ignored.

[0044] After observing the droplets encapsulating red blood cells under the microscope, the system is continuously monitored for 5 minutes. The camera captures images of red blood cells flowing through the microchannel in real time, recording the deformation and recovery process of red blood cells under the action of flow field and shear. The images are then imported into data processing module 2 to calculate the cell deformation coefficient, thus avoiding human error.

[0045] Step 5: After the test is completed, immediately turn off the injection pump 4. After all the remaining liquid in the capillary microchannel 3 has flowed into the collection device 5, classify and process the samples in the collection device 5. For cell waste and damaged cells, pour them into a special biological waste collection container. For red blood cells with good activity, separate the microdroplets from the cells by aseptic centrifugation, collect the precipitated active red blood cells, wash them 3 times with physiological saline, and they can be used for subsequent related experimental research. All sterile tubes and collection devices 5 that have come into contact with cells are disinfected by soaking in a solution containing 75% ethanol for 30 minutes. After disinfection, rinse them with sterile deionized water, air dry them, and store them properly to avoid cross-contamination.

[0046] Step 6: Plot the deformation coefficients of cells inside the microdroplets at different positions in the compression tube 8, analyze the influence of droplets of different sizes on the cell deformation coefficients, and select the optimal droplet size to protect the cells.

[0047] Example 2 See Figure 3 In this embodiment, human breast cancer cells (MCF-7) are used as the detection object. The detection system invented is used to explore the interaction law of multiple cells in the flow process of capillary microchannel 3 within the microdroplet, including the squeezing and cooperative deformation characteristics between cells. The detection system is fabricated and connected with reference to Example 1.

[0048] Step 1: Fabricate capillary microchannels 3. Select capillary microchannels 3 with a compression ratio of 2 / 3. The compression ratio is the ratio of the inner diameter of the compression tube 8 to the inner diameter of the inlet outer tube 7. Specifically, the inner diameter of the inlet inner tube 6 is 18 μm, the outer diameter is 25 μm, and the length is 400 μm; the inner diameter of the inlet outer tube 7 is 60 μm, the outer diameter is 70 μm, and the length is 1000 μm; the inner diameter of the compression tube 8 is 40 μm, the outer diameter is 48 μm, and the length is 800 μm; and the inner diameter of the recovery tube 9 is 60 μm, the outer diameter is 70 μm, and the length is 400 μm.

[0049] First, the inlet outer tube 7 is placed at the center of the substrate and fixed with glue to determine the reference position of the entire capillary microchannel 3. Then, the inlet inner tube 6 is inserted into the inlet outer tube 7 from the left, and the compression tube 8 is inserted into the inlet outer tube 7 from the right. The coaxiality of each capillary is calibrated under a microscope and initially fixed with glue. Subsequently, the recovery tube 9 is inserted to the right of the compression tube 8, and the overall coaxial alignment is ensured again by microscopic calibration, and then final fixation is completed with glue. The inlet inner tube 6 is inserted into the inlet outer tube 7 to a depth of 300 μm; the compression tube 8 is inserted into the inlet outer tube 7 and the recovery tube 9 to the same depth, 100 μm. Then, the capillary microchannel 3 and the connections of the tubing are sealed with glue, and left to stand for 48 hours to allow the glue to cure before use.

[0050] Step 2: Connect the inlet of the capillary microchannel 3 to the injection pump 4 and the outlet to the collection device 5, and seal the connection to ensure that all connections are sealed and leak-free. The preparation of the capillary microchannel 3 is now complete.

[0051] Step 3: Adjust the microscope position so that the lens is aligned with the compression tube 8 of the capillary microchannel 3; turn on the power to the microscope, data processing module 2, injection pump 4 and collection device 5, check the connection status of each component, and ensure that the signal connection of data processing module 2 is normal.

[0052] Step 4: After the detection device is assembled, first inject the continuous phase fluid into the capillary microchannel 3 through the inlet tube 7. Once the channel is completely filled with the continuous phase, then turn on the cell suspension injection pump. Using 12 μm diameter MCF-7 cells as inner cells, culture them in 1% bovine serum albumin phosphate buffer, adjusting the inlet flow rate to 20 μL / min. -1 Using silicone oil as the continuous phase, the droplet diameter was controlled between 25-40 μm by adjusting the continuous phase flow rate, ensuring that most droplets contained two cells and preventing cell adhesion to the inner wall of the microdroplets. Droplets containing two MCF-7 cells were observed, while other results were ignored.

[0053] After observing the droplet containing two MCF-7 cells under the microscope, the system was continuously monitored for 8 minutes. The camera captured the complete dynamic process of the microdroplet flowing through the capillary microchannel 3 in real time, focusing on recording the relative position changes and morphological differences of the cells within the microdroplet. The data processing module 2 analyzed the transmitted image data and calculated the cell deformation coefficient.

[0054] Step 5: After the test is completed, turn off the injection pump 4. After the liquid remaining in the capillary microchannel 3 has completely flowed into the collection device 5, disconnect the sterile tubing connections of each component to avoid sample leakage and contamination. All damaged cells and related waste liquid in the collection device 5 should be transferred to a dedicated biological waste collection container to retain viable cells for subsequent research. For viable MCF-7 cells, collect the precipitated viable cells by aseptic centrifugation, transfer them to a sterile cell culture flask, wash them three times with physiological saline, and they can be used for subsequent experimental research. All sterile tubing and the collection device 5 that have come into contact with cells should be disinfected by soaking in a solution containing 75% ethanol for 30 minutes. After disinfection, rinse thoroughly with sterile deionized water, air dry, and store properly to avoid cross-contamination.

[0055] Step 6: The deformation coefficients of multiple cells inside the microdroplet at different positions in the compression tube 8 are plotted into images to analyze the influence of droplets of different sizes on the cell deformation coefficients, and the optimal droplet size is selected to protect the cells.

[0056] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. It should be noted that any modifications, substitutions, improvements, etc., made by those skilled in the art within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An analytical detection system for the cell deformability characteristics within microdroplets, used to detect the effect of contraction channels on cell deformability, clarify the protective effect of droplets, and select droplets of optimal size, characterized in that, The analytical detection system includes a microscopic imaging module (1), a data processing module (2), a capillary microchannel (3), a sample injection pump (4), a collection device (5), an inner inlet tube (6), an outer inlet tube (7), a compression tube (8), and a recovery tube (9). Specifically: The microscopic imaging module (1) includes a microscope and its camera, used to observe the morphological changes of cells within microdroplets; the data processing module (2) is connected to the camera, used to receive images acquired by the camera and measure cell size, and to process the data based on the deformation coefficient. The deformation characteristics of cells are analyzed; the capillary microchannel (3) is placed on the microscope stage, its inlet is connected to the injection pump (4), and its outlet is connected to the collection device (5); the injection pump (4) includes a continuous phase injection pump and a cell suspension injection pump, which are used to inject cell suspension and continuous phase fluid into the capillary microchannel (3) and control the flow rate so that the cells are encapsulated in droplets; the collection device (5) adopts a sealed design and is connected to the outlet of the capillary microchannel (3) to collect the cells and waste liquid after detection; the microscope and camera acquire images of microdroplets and cells flowing through the capillary microchannel (3).

2. The analytical detection system for cell deformability characteristics within microdroplets according to claim 1, characterized in that, The capillary microchannel (3) includes an inner inlet tube (6), an outer inlet tube (7), a compression tube (8), and a recovery tube (9), all four tubes being coaxially mounted; specifically: The inner inlet tube (6) extends into the left end of the outer inlet tube (7), and its left port is connected to the cell suspension injection pump for introducing cell suspension into the inner inlet tube (6); the left port of the outer inlet tube (7) is connected to the continuous phase injection pump for introducing continuous phase between the outer wall of the inner inlet tube (6) and the inner wall of the outer inlet tube (7); the compression tube (8) is inserted from the right end of the outer inlet tube (7), and the right port of the compression tube (8) is inserted into the recovery tube (9), the right end of the recovery tube (9) is connected to the collection device (5); Cell suspension and continuous phase are introduced through the inner inlet tube (6) and the outer inlet tube (7). After the two phases are mixed at the right end of the outer inlet tube (7), they flow into the recovery tube (9) through the compression tube (8). The compression tube (8) realizes the mechanical deformation of cells in microdroplets. The recovery tube (9) is used to restore the mechanical deformation of cells.

3. The analytical detection system for cell deformability characteristics within microdroplets according to claim 2, characterized in that, In the capillary microchannel (3): The inner diameter of the inlet inner tube (6) is 10-30 μm and the wall thickness is 3-5 μm; the inner diameter of the inlet outer tube (7) is 50-80 μm and the wall thickness is 5-8 μm; the inner diameter of the compression tube (8) is 10-65 μm and the wall thickness is 3-6 μm; the inner diameter of the recovery tube (9) is 50-80 μm and the wall thickness is 5-8 μm; and the inner diameter of the recovery tube (9) is greater than the outer diameter of the compression tube (8), the outer diameter of the compression tube (8) is smaller than the inlet outer tube (7), and the inner diameter of the compression tube (8) is greater than the inner diameter of the inlet inner tube (6); The length of the inner inlet tube (6) is 400-500 μm; the length of the outer inlet tube (7) is 1000-1200 μm; the length of the recovery tube (9) is 600-1000 μm; the length of the recovery tube (9) is 300-500 μm; the depth to which the inner inlet tube (6) is inserted into the outer inlet tube (7) is 300-350 μm; the depth to which the compression tube (8) is inserted into the outer inlet tube (7) and the recovery tube (9) is the same, which is 50-100 μm.

4. The analytical detection system for cell deformability characteristics within microdroplets according to claim 2, characterized in that, The inner diameter of the inlet tube (7) and the recovery tube (9) in the capillary microchannel (3) is larger than the diameter of the microdroplet, and the inner diameter of the compression tube (8) in the capillary microchannel (3) is smaller than the diameter of the microdroplet.

5. The analytical detection system for cell deformability characteristics within microdroplets according to claim 2, characterized in that, The analytical detection system: The materials of the capillary microchannel (3) include glass, polymer, and metal; The continuous phase is silicone oil; the flow rate of the continuous phase is 100-400 μL·min. -1 ; The cell suspension is used to culture cells, which are human red blood cells and cancer cells, in a suspension that is either a polyethylene glycol solution or a phosphate buffer solution; the flow rate of the cell suspension is 10-100 μL / min. -1 .

6. The analytical detection system for cell deformability characteristics within microdroplets according to claim 2, characterized in that, The analytical detection system: The data processing module (2) processes the images captured by the camera, extracts the axial and radial diameters of the deformed cells, calculates the cell deformation coefficient, and generates an analysis report. The detection system can detect droplets containing different numbers of cells according to actual needs. When the droplet size is small, each droplet contains only one cell. Adjusting the continuous phase flow rate can make each droplet contain two or more cells, and the mutual compression phenomenon between cells can be observed.

7. The analytical detection system for cell deformability characteristics within microdroplets according to claim 2, characterized in that, The analytical detection system: The inlet of the capillary microchannel (3) is connected to the injection pump (4) and the outlet of the capillary microchannel (3) is connected to the collection device (5) through sterile hard tubes. The inner diameter of the tubes matches the inner diameter of the inlet and outlet of the capillary microchannel (3) to ensure the sealing and stability of the fluid transport. The compression ratio in the capillary microchannel (3) is changed according to actual needs, wherein the compression ratio is the ratio of the inner diameter of the compression tube (8) to the inner diameter of the inlet outer tube (7); the range of the compression ratio is between 1 / 4 and 3 / 4; The injection pump (4) adjusts the flow rate to change the flow ratio between the cell suspension and the continuous phase, thereby generating microdroplets of different sizes to meet the detection needs of cells of different sizes.

8. A method for analyzing and detecting the deformability characteristics of cells within microdroplets, characterized in that, Based on the analysis and detection system according to any one of claims 1-7, the method includes the following steps: Step 1: Place the inlet outer tube (7) in the center of the substrate, fix the reference position, and install the inlet inner tube (6), inlet outer tube (7), compression tube (8) and recovery tube (9). Ensure the coaxiality of all capillaries under a microscope. Step 2: Connect the inlet of the capillary microchannel (3) to the injection pump (4) and the outlet to the collection device (5), and seal the connection. The capillary microchannel (3) is now ready. Step 3: Adjust the microscope position so that the lens is aligned with the compression tube (8) of the capillary microchannel (3); turn on the power of the microscope, data processing module (2), injection pump (4) and collection device (5), check the connection status of each component, and ensure that the signal connection of the data processing module (2) is normal. Step 4: After the detection device is set up, the continuous phase fluid is first introduced through the inlet outer tube (7). After the inlet outer tube (7) is filled with the continuous phase fluid, the cell suspension injection pump is started to introduce the cell suspension from the inlet inner tube (6). When the flow pattern is stable, the deformation and recovery process of red blood cells under the action of flow field and shear are recorded. The image is imported into the data processing module (2). The data processing module (2) identifies the size change of the cell and calculates the cell deformation coefficient. Step 5: After the test is completed, turn off the injection pump (4). After all the remaining liquid in the capillary microchannel (3) flows into the collection device (5), classify the sample in the collection device (5). Step 6: Plot the deformation coefficient of the cell at different positions in the compression tube (8) into an image, analyze the effect of droplets of different sizes on the cell deformation coefficient, and select the droplet of the optimal size to protect the cell; The criterion for judging cell deformation is the deformation coefficient. The calculation method is as follows: in, a The axial diameter of the cell, in μm; b Radial diameter of the cell, unit: μm; coefficient of deformation Between -1 and 1, the closer to 0, the smaller the cell deformation.

9. The method for analyzing and detecting cell deformability characteristics within microdroplets according to claim 8, characterized in that, The substrate material in step 1 includes glass, polymer, or metal.

10. The method for analyzing and detecting cell deformability characteristics within microdroplets according to claim 8, characterized in that, The classification process in step 5 is as follows: for cell waste liquid and damaged cells, pour them into a biological waste liquid collection container; for cells with good activity, separate microdroplets from cells by aseptic centrifugation, collect the precipitated active cells, and use them for subsequent related experimental research.

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