A micron particle size distribution testing device

Abstract

The present invention provides a micron particle size distribution test device, comprising a microfluidic chip and an information acquisition and analysis unit; the microfluidic chip is provided with a microchannel; the microchannel comprises a sample flow channel, an extrusion flow channel, a separation channel and a discharge area; the extrusion flow channel introduces a pure fluid, and the sample flow channel introduces a sample fluid; the flow rate of the pure fluid is greater than the flow rate of the sample fluid; the sample flow channel, the separation channel and the discharge area are sequentially connected and arranged along a first direction, the extrusion flow channel is connected between the sample flow channel and the separation channel, and there is an angle relationship between the extrusion flow channel and the first direction; the flow area of ​​the separation channel is smaller than the flow area of ​​the sample flow channel; the discharge area comprises a plurality of discharge channels arranged in parallel with the first direction, and the plurality of discharge channels are arranged at intervals; the information acquisition and analysis unit monitors the discharge area, analyzes the number of micron particles flowing through each discharge channel, so as to obtain the micron particle size distribution information of the sample fluid. The structure is simple and the test accuracy is high.

Description

Technical Field

[0001] The invention belongs to the technical field of particle size distribution testing of micron particle materials, and in particular relates to a device for testing the particle size distribution of micron particles. Background Art

[0002] Micron particle materials are currently widely used in various fields, and they play an important role in energy, semiconductors, electronics, medicine, chemical engineering, bioengineering, cosmetics and other fields. The size and distribution of micron particles are one of the key parameters of the material, which has a vital impact on the subsequent performance and application of micron particles, as well as product development. Therefore, the test of particle size distribution of micron particle materials is a basic and key technical requirement.

[0003] At present, mature methods for testing the particle size distribution of micron particles include laser diffraction, dynamic light scattering, microscopy, screening, etc. However, these methods either require the application of complex principles, rely on expensive equipment support and skilled manual operation, or are inefficient, or require a large amount of samples during the test process. The limitations of existing particle size distribution test methods for micron particles have led to increased costs and limited production efficiency, making it difficult to meet the current application needs of micron particle materials. Summary of the invention

[0004] The technical purpose of the present invention is to provide a micron particle size distribution testing device, which aims to solve the technical problems in the related art that the testing method needs to apply complex principles, rely on expensive equipment support and skilled manual operation, or is inefficient, or requires a large amount of samples during the testing process.

[0005] To solve the above technical problems, the present invention is implemented as follows: a micron particle size distribution test device comprises a microfluidic chip and an information acquisition and analysis unit; the microfluidic chip is provided with a microchannel; the microchannel comprises a sample flow channel, an extrusion flow channel, a separation channel and a discharge area; the extrusion flow channel is used to introduce a pure fluid, and the sample flow channel is used to introduce a sample fluid; the flow rate of the pure fluid is greater than the flow rate of the sample fluid; the sample flow channel, the separation channel and the discharge area are sequentially connected and arranged along a first direction, the extrusion flow channel is connected between the sample flow channel and the separation channel, and there is an angle relationship between the extrusion flow channel and the first direction; the flow area of ​​the separation channel is smaller than the flow area of ​​the sample flow channel; the discharge area comprises a plurality of discharge channels arranged parallel to the first direction, and the plurality of discharge channels are arranged at intervals; the information acquisition and analysis unit is used to monitor the discharge area, and to analyze the number of micron particles flowing through each of the discharge channels, so as to obtain the micron particle size distribution information of the sample fluid.

[0006] Furthermore, in some embodiments, the information acquisition and analysis unit includes a microscope module, a camera module and an information processing module, the microscope module focuses on the discharge area and / or the microchannel, the camera module is used to perform image monitoring of the discharge area under the microscope module, and the information processing module is used to analyze and statistically obtain micron particle size distribution information of the sample fluid based on the image monitoring results.

[0007] Furthermore, in some embodiments, the ratio of the flow rate of the sample fluid to the flow rate of the pure fluid ranges from 0.006 to 0.02.

[0008] Furthermore, in some embodiments, the flow rate V1 of the sample fluid has a numerical range of 0.0048 mL / min to 0.0072 mL / min, and the flow rate V2 of the pure fluid has a numerical range of 0.48 mL / min to 0.72 mL / min.

[0009] Further, in some embodiments, the ratio of the transverse cross-sectional width w of the separation channel to the transverse cross-sectional width W of the sample flow channel is in the range of 0.3 to 0.8.

[0010] Furthermore, in some embodiments, the transverse cross-sectional width w of the separation channel ranges from 100 μm to 150 μm, and the transverse cross-sectional width W of the sample flow channel ranges from 200 μm to 300 μm.

[0011] Further, in some embodiments, the sample flow channel includes a first outlet channel, the extrusion flow channel includes a second outlet channel, the first outlet channel is connected to the second outlet channel and both are connected to the separation channel, the ratio of the flow area of ​​the first outlet channel to the flow area of ​​the second outlet channel is between 0.986-1.014, and the ratio of the flow area of ​​the first outlet channel to the flow area of ​​the discharge channel is between 0.986-1.014.

[0012] Furthermore, in some embodiments, the testing device further comprises an injection system and a liquid transfer device, wherein the injection system is connected to the sample flow channel to introduce a sample fluid; and the liquid transfer device is connected to the extrusion flow channel to introduce a pure fluid.

[0013] Furthermore, in some embodiments, the testing device further includes a discharge liquid collection system, wherein the discharge liquid collection system includes a plurality of collection areas corresponding one-to-one to the discharge channels, and the collection areas are connected to the discharge channels.

[0014] Further, in some embodiments, the testing device also includes an electric translation stage, the discharge liquid collection system is mounted on the electric translation stage, the discharge liquid collection system includes a plurality of collection spaces arranged at intervals along the moving direction of the electric translation stage, and each of the collection spaces includes the plurality of collection areas.

[0015] Compared with the related art, the micron particle size distribution testing device of the present invention has the following beneficial effects:

[0016] In the embodiment of the present invention, since the sample flow channel, the separation channel and the discharge area are sequentially connected and arranged along the first direction, and the extrusion flow channel connected between the sample flow channel and the separation channel has an angle relationship with the first direction; and since the flow area of ​​the separation channel is smaller than the flow area of ​​the sample flow channel, that is, the separation channel is relatively narrow; and at the same time, the flow rate of the pure fluid is much greater than the flow rate of the sample fluid, therefore, when the sample fluid flows toward the separation channel along the first direction, and the pure fluid flows toward the separation channel along the direction having an angle relationship with the first direction, an extrusion flow can be formed in the separation channel. That is to say, the embodiment of the present invention can realize the extrusion of the sample fluid with micron particles by introducing a pure fluid with a high flow rate and flowing obliquely or vertically relative to the sample fluid into a narrow separation channel. Under the influence of the extrusion flow, in the process of flowing from the separation channel to the discharge area, the larger micron particles in the sample fluid tend to maintain the original trajectory, that is, flow along the first direction and remain in the middle of the channel, while the smaller micron particles also flow along the first direction but tend to be pushed to the channel wall. In addition, the discharge area includes a plurality of discharge channels that are parallel to the first direction and spaced apart. Therefore, under the influence of the extrusion flow, micron particles of different sizes will enter different discharge channels, and micron particles of the same size will enter the same discharge channel. The information acquisition and analysis unit can monitor each discharge channel, and can analyze the number of micron particles in each discharge channel according to the monitoring situation, so as to know the distribution of different particle sizes of micron particles in the sample fluid, and realize the test of the particle size distribution of micron particles in the sample fluid.

[0017] The embodiment of the present invention can simplify the composition of the sample fluid by designing the microchannel and introducing pure fluid, so that micron particles of different particle sizes in the sample fluid can be classified and separated, and the deviation of the test results caused by the complexity of the sample fluid and the unstable environment can be reduced as much as possible, thereby improving the accuracy of the test results. In addition, by applying the microchannel to the particle size distribution measurement, the sample consumption can be significantly reduced and the cost can be reduced; at the same time, the particle size distribution results can be measured quickly to ensure the measurement accuracy, without relying on expensive equipment with harsh use conditions and high operating requirements, which greatly reduces the test cost. In addition, the microchannel has a simple structure, so that the fluid flow resistance is relatively small, rapid separation can be achieved, and the accuracy of the test results can be further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 is a schematic structural diagram of a device for testing the particle size distribution of micron particles according to an embodiment of the present invention;

[0020] Figure 2 is a schematic diagram of the structure of a microfluidic chip in an embodiment of the present invention;

[0021] Figure 3 is a schematic diagram of the structure of a microchannel in an embodiment of the present invention;

[0022] Figure 4 yes Figure 3 A magnified view of detail A;

[0023] Figure 5 Schematic diagram of the principle of separation of micron particles and measurement of particle size distribution based on extrusion flow in an embodiment of the present invention;

[0024] Figure 6 Schematic diagram of simulation results of micron particle separation based on extrusion flow of the microfluidic chip in an embodiment of the present invention, wherein (a) simulates the separation of micron particles with a particle size range of 5 μm to 100 μm; (b) simulates the separation of micron particles with a particle size range of 30 μm to 35 μm;

[0025] Figure 7 It is a schematic diagram of the process flow of manufacturing microchannels in a microfluidic chip according to an embodiment of the present invention.

[0026] In the accompanying drawings, each figure mark represents: 1. microfluidic chip; 11. microchannel; 111. sample flow channel; 1111. first inlet; 1112. first outlet channel; 112. extrusion flow channel; 1121. second inlet; 1122. second outlet channel; 113. separation channel; 114. discharge area; 1141. discharge channel; 1142. guide channel; 2. information acquisition and analysis unit; 3. injection system; 4. liquid transfer equipment; 5. discharge liquid collection system; 6. electric translation stage; 7. sample fluid array to be tested; 10. first substrate layer; 101. through hole; 102. connecting groove; 20. second substrate layer. DETAILED DESCRIPTION

[0027] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but are not to be construed as limiting the present invention. All other embodiments obtained by ordinary technicians in the field without creative work based on the embodiments of the present invention are within the scope of protection of the present invention.

[0028] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "circumferential", "radial" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0029] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0030] See also Figures 1 to 6 The embodiment of the present invention provides a micron particle size distribution testing device, comprising a microfluidic chip 1 and an information acquisition and analysis unit 2; the microfluidic chip 1 is provided with a microchannel 11; the microchannel 11 comprises a sample flow channel 111, an extrusion flow channel 112, a separation channel 113 and a discharge area 114; the extrusion flow channel 112 is used to introduce a pure fluid, and the sample flow channel 111 is used to introduce a sample fluid; the flow rate of the pure fluid is greater than the flow rate of the sample fluid; the sample flow channel 111, the separation channel 113 and the discharge area 114 are sequentially connected and arranged along a first direction, and ... sample flow channel 111, the separation channel 113 and the discharge area 114 are sequentially connected and arranged along a first direction, and the extrusion flow channel 112 is used to introduce a pure fluid, and the sample flow channel 111 is used to introduce a sample fluid; the sample flow channel 111, the separation channel 113 and the discharge area 114 are sequentially connected and arranged along a first direction, and the extrusion flow channel The flow channel 112 is connected between the sample flow channel 111 and the separation channel 113, and there is an angle relationship between the extrusion flow channel 112 and the first direction; the flow area of ​​the separation channel 113 is smaller than the flow area of ​​the sample flow channel 111; the discharge area 114 includes a plurality of discharge channels 1141 arranged parallel to the first direction, and the plurality of discharge channels 1141 are arranged at intervals; the information acquisition and analysis unit 2 is used to monitor the discharge area 114, and to analyze the number of micron particles flowing through each discharge channel 1141, so as to obtain the micron particle size distribution information of the sample fluid.

[0031] In the embodiment of the present invention, since the sample flow channel 111, the separation channel 113 and the discharge area 114 are sequentially connected and arranged along the first direction, and the extrusion flow channel 112 connected between the sample flow channel 111 and the separation channel 113 has an angle relationship with the first direction; and since the flow area of ​​the separation channel 113 is smaller than the flow area of ​​the sample flow channel 111, that is, the separation channel 113 is relatively narrow; and at the same time, the flow rate of the pure fluid is much greater than the flow rate of the sample fluid, therefore, when the sample fluid flows toward the separation channel 113 along the first direction and the pure fluid flows toward the separation channel 113 along the direction having an angle relationship with the first direction, an extrusion flow can be formed in the separation channel 113. That is to say, the embodiment of the present invention can realize the extrusion of the sample fluid with micron particles by introducing a pure fluid with a high flow rate and flowing obliquely or vertically relative to the sample fluid into a narrow separation channel 113. Under the influence of the squeeze flow, in the process of flowing from the separation channel 113 to the discharge area 114, the larger micron particles in the sample fluid tend to maintain the original trajectory, that is, flow along the first direction and remain in the middle of the channel, while the smaller micron particles also flow along the first direction but tend to be pushed to the channel wall. In addition, the discharge area 114 includes a plurality of discharge channels 1141 that are parallel to the first direction and spaced apart. Therefore, under the influence of the squeeze flow, micron particles of different particle sizes will enter different discharge channels 1141, and micron particles of the same particle size will enter the same discharge channel 1141. The information acquisition and analysis unit 2 can monitor each discharge channel 1141, and can also analyze the number of micron particles in each discharge channel 1141 based on the monitoring situation, so as to know the different particle size distribution of micron particles in the sample fluid, and realize the test of the particle size distribution of micron particles in the sample fluid.

[0032] The embodiment of the present invention can simplify the composition of the sample fluid by designing the microchannel 11 and introducing pure fluid, so that micron particles of different particle sizes in the sample fluid can be classified and separated, and the deviation of the test results caused by the complexity of the sample fluid and the unstable environment can be reduced as much as possible, thereby improving the accuracy of the test results. In addition, by applying the microchannel 11 to the particle size distribution measurement, the sample consumption can be significantly reduced and the cost can be reduced; at the same time, the particle size distribution results can be measured quickly to ensure the measurement accuracy; and there is no need to rely on expensive equipment with harsh use conditions and high operating requirements, which greatly reduces the test cost. In addition, the microchannel 11 has a simple structure, so that the fluid flow resistance is relatively small, rapid separation can be achieved, and the accuracy of the test results can be further improved.

[0033] In addition, it can be understood that the flow area is expressed as the area when the fluid flows through, that is, it represents the area of ​​the transverse cross-section of each channel.

[0034] Furthermore, in some embodiments, the angular relationship between the central axis of the extrusion flow channel 112 and the central axis of the sample flow channel 111 ranges from 45° to 110°.

[0035] Specifically, the first direction is the setting direction of the sample flow channel 111, the separation channel 113 and the discharge area 114, which is specifically manifested as the central axis of the sample flow channel 111, the central axis of the separation channel 113 and the central axis of the discharge area 114 are parallel to the first direction. The extrusion flow channel 112 has an angle relationship with the first direction, which is actually the central axis of the extrusion flow channel 112 and the central axis of the sample flow channel 111 (the central axis of the separation channel 113, the central axis of the discharge area 114) have an angle relationship. The angle relationship can be specifically 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, 90°, 95°, 100°, 105° or 110°, etc. In the angle range of 45°~110°, when the sample fluid flows from the sample flow channel 111 to the separation channel 113, and the pure fluid flows from the extrusion flow channel 112 to the separation channel 113, the pure fluid can better and faster extrude the sample fluid with micron particles, thereby better forming an extrusion flow, so that the micron particles in the sample fluid can be better separated and classified, and then the particle size distribution of the micron particles in the sample fluid can be tested more quickly.

[0036] Furthermore, in some embodiments, the information acquisition and analysis unit 2 includes a microscope module, a camera module and an information processing module. The microscope module focuses on the discharge area 114 and / or the microchannel 11, the camera module is used to perform image monitoring of the discharge area 114 under the microscope module, and the information processing module is used to analyze and statistically obtain the micron particle size distribution information of the sample fluid based on the image monitoring results.

[0037] Specifically, by focusing the microscope module on the discharge area 114 and / or the entire microchannel 11, the microscope module can magnify the discharge area 114 and / or the entire microchannel 11. At the same time, the camera module can perform real-time image monitoring of all discharge channels 1141, so that the discharge channel 1141 forms an observation counting area; the image monitoring results can be transmitted to the information processing module, so that the information processing module can analyze and count the number of micron particles flowing to different discharge channels 1141, and finally the particle size distribution of the micron particles in the sample fluid can be quickly obtained based on the statistical results. In an embodiment of the present invention, the method of separating the micron particles first and then monitoring and counting the number is adopted to infer the particle size distribution of the micron particles. In this way, not only can the rapid measurement of the particle size distribution result be achieved to ensure the measurement accuracy, but also the test can be completed by combining with a microscope equipped with a high-speed camera. The structure is simple, the space is small, and there is no need to rely on expensive equipment with harsh use conditions and high operating requirements, which greatly reduces the test cost.

[0038] Exemplarily, the information acquisition and analysis unit 2 may be a microscope integrated with a high-speed camera.

[0039] It can be understood that in the observation and counting area, along the spacing arrangement direction of each discharge channel 1141, that is, the direction orthogonal to the first direction, the particle size of the micron particles farther away from the extrusion flow channel 112 is smaller. Figure 5 As shown, there exists D1>D2>D3>···>D n relationship.

[0040] Furthermore, in some embodiments, the ratio of the flow rate of the sample fluid to the flow rate of the pure fluid ranges from 0.006 to 0.02.

[0041] Specifically, the ratio of the flow rate of the sample fluid to the flow rate of the pure fluid can be 0.006, 0.0065, 0.007, 0.008, 0.009, 0.01, 0.011, 0.012, 0.013, 0.014, 0.015, 0.016, 0.017, 0.018, 0.019 or 0.02, etc. By setting the ratio of the flow rate of the sample fluid to the flow rate of the pure fluid in the range of 0.006~0.02, the flow rate of the pure fluid can be much greater than the flow rate of the sample fluid. Under the action of fluid lift and drag, the larger micron particles in the sample fluid tend to maintain the original trajectory, that is, flow along the first direction and remain in the middle of the channel, while the smaller micron particles also flow along the first direction but tend to be pushed to the channel wall, ensuring a better fluid squeezing effect, so that the micron particles in the sample fluid can be better separated and classified, and then the particle size distribution of the micron particles in the sample fluid can be tested more quickly.

[0042] For further information, see Figure 5 In some embodiments, the flow rate V1 of the sample fluid ranges from 0.0048 mL / min to 0.0072 mL / min, and the flow rate V2 of the pure fluid ranges from 0.48 mL / min to 0.72 mL / min.

[0043] Specifically, the flow rate of the sample fluid may indicate the flow rate when the sample fluid is introduced into the sample flow channel 111 , and the flow rate of the pure fluid may indicate the flow rate when the pure fluid is introduced into the extrusion flow channel 112 . Among them, the flow rate of the sample fluid can be 0.0048mL / min, 0.005mL / min, 0.0052mL / min, 0.0055mL / min, 0.0058mL / min, 0.006mL / min, 0.0062mL / min, 0.0065mL / min, 0.0068mL / min, 0.007mL / min or 0.0072mL / min, etc.; the flow rate of the pure fluid can be 0.48mL / min, 0.5mL / min, 0.52mL / min, 0.55mL / min, 0.58mL / min, 0.6mL / min, 0.62mL / min, 0.65mL / min, 0.68mL / min, 0.7mL / min or 0.72mL / min, etc. By setting the flow rate range of the sample fluid to 0.0048mL / min~0.0072mL / min, the flow state of the sample fluid can be better controlled, so that the sample fluid will not adhere to the sample flow channel 111 due to too slow speed; nor will it rush directly to the separation channel 113 due to too fast speed, so that there will be no problem of not having enough time to contact with the pure fluid and unable to form an extrusion flow. By setting the flow rate range of the pure fluid to 0.48mL / min~0.72mL / min, the flow state of the pure fluid can also be better controlled, so that the pure fluid will not impact the channel wall due to too fast speed, and the sample fluid can be better squeezed at a higher flow rate to ensure a better fluid squeezing effect, that is, the squeezing flow can be better formed, so that the micron particles in the sample fluid can be better separated and classified, and then the particle size distribution of the micron particles in the sample fluid can be tested more quickly.

[0044] For further information, see Figure 4 In some embodiments, the ratio of the transverse cross-sectional width w of the separation channel 113 to the transverse cross-sectional width W of the sample flow channel 111 ranges from 0.3 to 0.8.

[0045] Specifically, the flow area of ​​the microchannel 11 depends on the depth of the transverse section of the microchannel 11 and the width of the transverse section of the microchannel 11. In some specific embodiments, the depths of the sample flow channel 111, the extrusion flow channel 112, the separation channel 113 and the discharge area 114 can be equal or extremely close. Therefore, the relative size of the flow area of ​​the sample flow channel 111 and the flow area of ​​the separation channel 113 depends on the relative size of the transverse section width W of the sample flow channel 111 and the transverse section width w of the separation channel 113. By setting the ratio of W to w between 0.3 and 0.8, the transverse section width w of the separation channel 113 is smaller than the transverse section width W of the sample flow channel 111, so that the separation channel 113 is formed into a narrow channel, which can ensure a better fluid extrusion effect, that is, the extrusion flow can be better formed, so that the test of the particle size distribution of the micron particles of the sample fluid can be realized more quickly; at the same time, it can prevent the channel from being blocked and ensure the smoothness of the fluid flow.

[0046] Illustratively, the depth of the microchannel 11 may be 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, 200 μm, 210 μm, 220 μm, 230 μm, 240 μm, 250 μm, and so on.

[0047] In some specific embodiments, the depth of the microchannel 11 is not equal everywhere. In this case, the ratio of the flow area of ​​the sample flow channel 111 to the flow area of ​​the separation channel 113 can be adjusted between 0.3 and 0.8, which can also ensure a better fluid extrusion effect and prevent channel blockage.

[0048] For further information, see Figure 4 In some embodiments, the width w of the transverse section of the separation channel 113 ranges from 100 μm to 150 μm, and the width W of the transverse section of the sample flow channel 111 ranges from 200 μm to 300 μm.

[0049] Specifically, the transverse cross-sectional width w of the separation channel 113 can be 100μm, 105μm, 110μm, 115μm, 120μm, 125μm, 130μm, 135μm, 140μm, 145μm or 150μm, etc.; the transverse cross-sectional width W of the sample flow channel 111 can be 200μm, 205μm, 210μm, 215μm, 220μm, 225μm, 230μm, 235μm, 240μm, 245μm, 250μm, 255μm, 260μm, 265μm, 270μm, 275μm, 280μm, 285μm, 290μm, 295μm or 300μm, etc. Generally, the maximum value of the micron particle size of the sample fluid is usually between 90 μm and 110 μm. Therefore, by setting the transverse cross-sectional width range w of the separation channel 113 to 100 μm to 150 μm and the transverse cross-sectional width range W of the sample flow channel 111 to 200 μm to 300 μm, the test device can be applied to sample fluids within the usual particle size range, thereby improving the practicality of the test device. Moreover, such a setting can make the transverse cross-sectional width of the separation channel 113 smaller than the transverse cross-sectional width of the sample flow channel 111, so that the separation channel 113 forms a narrow channel, which can ensure a better fluid extrusion effect, that is, a better extrusion flow can be formed, so that the test of the particle size distribution of the micron particles of the sample fluid can be realized more quickly; at the same time, it can also prevent blockage and ensure the smoothness of fluid flow.

[0050] For further information, see Figure 3 and Figure 4 In some embodiments, the sample flow channel 111 includes a first outlet channel 1112, the extrusion flow channel 112 includes a second outlet channel 1122, the first outlet channel 1112 is connected to the second outlet channel 1122 and both are connected to the separation channel 113, the ratio of the flow area of ​​the first outlet channel 1112 to the flow area of ​​the second outlet channel 1122 is in the range of 0.986-1.014, and the ratio of the flow area of ​​the first outlet channel 1112 to the flow area of ​​the discharge channel 1141 is in the range of 0.986-1.014.

[0051] Specifically, the sample flow channel 111 includes a first inlet 1111 and a first outlet channel 1112, and the sample fluid flows from the first inlet 1111 to the first outlet channel 1112; the extrusion flow channel 112 includes a second inlet 1121 and a second outlet channel 1122, and the pure fluid flows from the second inlet 1121 to the second outlet channel 1122. The ratio of the flow area of ​​the first outlet channel 1112 to the flow area of ​​the second outlet channel 1122 may be 0.986, 0.99, 0.995, 0.996, 0.997, 0.998, 0.999, 1, 1.001, 1.002, 1.003, 1.004, 1.005, 1.008, 1.01, 1.012 or 1.014. and so on; the ratio of the flow area of ​​the first outlet channel 1112 to the flow area of ​​the discharge channel 1141 can be 0.986, 0.99, 0.995, 0.996, 0.997, 0.998, 0.999, 1, 1.001, 1.002, 1.003, 1.004, 1.005, 1.008, 1.01, 1.012 or 1.014 and so on.

[0052] By setting the ratio of the flow area of ​​the first outlet channel 1112 to the flow area of ​​the second outlet channel 1122 to be between 0.986 and 1.014, and the ratio of the flow area of ​​the first outlet channel 1112 to the flow area of ​​the discharge channel 1141 to be between 0.986 and 1.014, a better extrusion flow effect can be ensured between the first outlet channel 1112, the second outlet channel 1122 and the discharge channel 1141, so that micron particles of different particle sizes can flow well to different discharge channels 1141; at the same time, it is shown that the flow area of ​​the extrusion flow channel 112 can be slightly smaller than, equal to or slightly larger than the flow area of ​​the sample flow channel 111, and the flow area of ​​the discharge channel 1141 can be slightly smaller than, equal to or slightly larger than the flow area of ​​the sample flow channel 111, that is, some deviations in the process manufacturing process are allowed to reduce the manufacturing difficulty.

[0053] In addition, it should be noted that the first inlet 1111 represents an opening at the inlet, and the first outlet channel 1112 represents a section of the channel at the outlet, and the first inlet 1111 and the first outlet channel 1112 are located at both ends of the sample flow channel 111, but they are not the same structure. Similarly, the second inlet 1121 represents an opening at the inlet, and the second outlet channel 1122 represents a section of the channel at the outlet, and the second inlet 1121 and the second outlet channel 1122 are located at both ends of the extrusion flow channel 112, but they are not the same structure.

[0054] For further information, see Figure 3 and Figure 4In some feasible embodiments, the sample flow channel 111 includes a first flow channel between a first inlet 1111 and a first outlet channel 1112, and the first flow channel tapers along the flow direction of the sample fluid; the extrusion flow channel 112 includes a second flow channel between a second inlet 1121 and a second outlet channel 1122, and the second flow channel tapers along the flow direction of the pure fluid, and the first flow channel and the second flow channel can taper synchronously.

[0055] Specifically, when the sample fluid is introduced, the flow rate is constant. Therefore, by setting the first flow channel to taper along the flow direction of the sample fluid, the speed of the sample fluid during the flow process can be promoted to a certain extent. Similarly, when the pure fluid is introduced, the flow rate is constant. Therefore, by setting the extrusion flow channel 112 to taper along the flow direction of the pure fluid, the speed of the pure fluid during the flow process can be promoted to a certain extent. In addition, the sample flow channel 111 and the extrusion flow channel 112 are synchronously tapered, so that the relative size of the flow rate of the sample fluid and the pure fluid can represent the relative speed of the flow of the two, and will not be affected by the size of the flow area of ​​the sample flow channel 111 and the extrusion flow channel 112. Therefore, at this time, the formation of the extrusion flow can be controlled by adjusting the relative size of the flow rate of the sample fluid and the pure fluid.

[0056] In addition, it can be understood that synchronous tapering does not mean that the shrinkage amount of the first flow channel and the second flow channel is always equal. The shrinkage amount of the first flow channel can be set to be slightly larger than, equal to, or slightly smaller than the shrinkage amount of the second flow channel.

[0057] In some embodiments, the flow areas of the sample flow channel 111 and the extrusion flow channel 112 are completely equal everywhere, that is, the first flow channel and the second flow channel are exactly the same, and the first outlet channel 1112 and the second outlet channel 1122 are exactly the same. Similarly, the formation of the extrusion flow can be controlled by adjusting the relative size of the flow rates of the sample fluid and the pure fluid.

[0058] It can be understood that the flow rate of the sample fluid indicates the flow rate when the sample fluid is introduced into the sample flow channel 111, which actually indicates that the sample fluid is introduced into the sample flow channel 111 at a certain fluid flow rate; and the speed of the sample fluid in the sample flow channel 111 can be expressed as the speed of the sample fluid flowing in the sample flow channel 111. Similarly, the flow rate of the pure fluid indicates the flow rate when the pure fluid is introduced into the extrusion flow channel 112, which actually indicates that the pure fluid is introduced into the sample flow channel 111 at a certain fluid flow rate; and the speed of the pure fluid in the extrusion flow channel 112 can be expressed as the speed of the pure fluid flowing in the extrusion flow channel 112.

[0059] For further information, see Figure 1In some embodiments, the testing device further includes an injection system 3 and a liquid transfer device 4. The injection system 3 is connected to the sample flow channel 111 to introduce the sample fluid; the liquid transfer device 4 is connected to the extrusion flow channel 112 to introduce the pure fluid.

[0060] Specifically, the injection system 3 can be a conventional automatic injection system, and the sample flow channel 111 and the injection system 3 can be connected through a catheter. During the operation, automatic injection can be achieved through instructions such as buttons or program settings, and the samples only need to be prepared and placed in order. In addition, the liquid transfer device 4 can be a liquid pumping device, and illustratively, it can be a syringe pump or a peristaltic pump. The extrusion flow channel 112 and the liquid transfer device 4 can also be connected through a catheter. In the actual process, the sample to be tested can be dispersed in a specific liquid (such as water) and then introduced into the microfluidic chip 1 through the automatic injection system, specifically, it can be introduced into the first inlet 1111 of the sample flow channel 111 at a certain flow rate; at the same time, the pure fluid can be introduced into the microfluidic chip 1 through the liquid transfer device 4 at a much higher inflow rate than the sample fluid, specifically, it can be introduced into the extrusion flow channel 112.

[0061] For further information, see Figure 1 In some embodiments, the testing device further includes a discharge liquid collection system 5 , which includes a plurality of collection areas corresponding one to one with the discharge channels 1141 , and the collection areas are connected to the discharge channels 1141 .

[0062] Specifically, the discharge channel 1141 and the corresponding collection area can be connected through a conduit, and multiple discharge channels 1141 correspond to multiple conduits, so that the discharge channels 1141, the conduits and the collection areas correspond one to one. In the microfluidic chip 1, the sample fluid after extrusion flow separation and high-speed microscopic image analysis can be discharged into each collection area of ​​the discharge liquid collection system 5 through the discharge channel 1141, wherein different collection areas correspond to different discharge channels 1141, and different discharge channels 1141 correspond to micron particles of different particle sizes in the sample fluid, so that classified micron particles of different particle sizes can be collected in the collection area, which can be used for subsequent more in-depth measurements.

[0063] For further information, see Figure 1 In some embodiments, the testing device further includes an electric translation stage 6, and the discharge liquid collection system 5 is mounted on the electric translation stage 6. The discharge liquid collection system 5 includes a plurality of collection spaces arranged at intervals along the moving direction of the electric translation stage 6, and each collection space includes a plurality of collection areas.

[0064] Specifically, the electric translation stage 6 can be a conventional automated device with a load-bearing structure and the load-bearing structure can be translated. The discharge liquid collection system 5 can be assembled and connected with the load-bearing structure so that the discharge liquid collection system 5 and the load-bearing structure can be translated synchronously. In addition, the discharge liquid collection system 5 includes a plurality of collection spaces, and the plurality of collection spaces are arranged at intervals along the moving direction of the electric translation stage 6. In this way, when the electric translation stage 6 is translated, the position of the collection space can also be automatically switched. In addition, each collection space includes a plurality of collection areas, and these plurality of collection areas correspond to a test of a sample fluid, that is, one collection space can correspond to a test of a sample fluid. When a new sample fluid is tested, a new collection space can be corresponded, so that the discharge channel 1141 can correspond to a new collection area. In this way, the discharge liquid collection system 5 can also collect different types of sample fluids at the same time. Since the multiple collection spaces are arranged at intervals along the moving direction of the electric translation stage 6, when testing a new sample fluid, the current collection space can be automatically switched to a new collection space, so that the discharge channel 1141 can correspond to the new collection area, which can reduce manual intervention. It is only necessary to connect the catheter connected to the discharge channel 1141 to the new collection area.

[0065] Exemplarily, the discharge liquid collection system 5 can be a porous plate, and the porous plate can be placed on the electric translation stage 6. The porous plate includes a plurality of micro-wells arranged in an array, and each micro-well can be used as a collection area, so that a plurality of collection spaces can be divided.

[0066] For further information, see Figure 1 In some embodiments, the test device may further include a sample fluid array 7 to be tested. For example, the sample fluid array 7 to be tested may be another porous plate, and the other porous plate collects multiple types of sample fluids, and each micropore collects a sample fluid. In this way, the different sample fluids on the porous plate can be sequentially and orderly flowed through the microchannel 11 of the microfluidic chip 1 by the automatic injection system, and the electric translation stage 6 can be synchronously translated to replace different collection spaces, so that there is no need to go through the "injection-testing-retraction" cycle process like the traditional test method, and continuous operation can be achieved, so that the particle size distribution test for different sample fluids can be carried out continuously and orderly, and manual intervention can be reduced. Moreover, this continuous test method also makes online real-time monitoring possible, and the micron particle size distribution of the sample fluid on the production line can be synchronously tested to monitor product quality, thereby optimizing the process and efficiency of quality monitoring. In addition, the porous plate structure can further prove that the test method of the embodiment of the present invention can significantly reduce sample consumption and reduce costs compared with the traditional test method.

[0067] Furthermore, in practical applications, before testing a new sample, a pure fluid (for example, water or ethanol) can be introduced into the first inlet 1111 of the sample flow channel 111 to clean the microchannel 11. Specifically, the automatic injection system is switched to pure fluid injection, and then switched to a new sample after washing. The washing liquid does not need to be collected and reused, and can be directly discarded.

[0068] Furthermore, different types of sample fluids have different particle size distributions, so different test processes will present different micron particle discharge forms. For example, different sample fluids correspond to different discharge channels 1141 during each test, and the number of micron particles in the same discharge channel 1141 is different. Figure 6 , Figure 6 is a schematic diagram of simulation results of micron particle separation based on extrusion flow of the microfluidic chip 1 in an embodiment of the present invention, wherein: Figure 6 (a) simulates the separation of micron particles with a size range of 5 μm to 100 μm; Figure 6 (b) simulates the separation of micron particles with a particle size range of 30 μm to 35 μm. It can be seen that the test method according to the embodiment of the present invention can quickly distinguish and evaluate micron particles in different sample fluids through continuous and orderly operations and combined with image collection of the microscope module and the camera module.

[0069] Compared with the existing testing methods, the testing method of the embodiment of the present invention is more intuitive and clear, and can easily and instantly obtain the particle size distribution results of micron particles. Exemplarily, when used for the detection of material quality and performance, the particle size distribution test method of the embodiment of the present invention can better compare and judge the various materials based on the test results of the various materials, so that in the production process, it can be immediately determined which material can better meet the development needs of the product. In this way, the embodiment of the present invention is more conducive to product testing. In addition, the embodiment of the present invention can also significantly reduce sample consumption and reduce costs; and the structure is simple, without relying on expensive equipment with harsh use conditions and high operating requirements, which greatly reduces the cost of testing; at the same time, it can reduce the deviation of test results caused by environmental instability. In addition, the real-time online monitoring capability is also improved.

[0070] Further, in some embodiments, in order to enable the discharge liquid collection system 5 to be better connected to the microfluidic chip 1, a guide channel 1142 connected to the discharge channel 1141 can be opened in the microfluidic chip 1, that is, the discharge area 114 also includes a plurality of guide channels 1142 corresponding to the plurality of discharge channels 1141, so that the discharge area 114 of the discharge liquid collection system 5 can be connected to the discharge channel 1141 through the guide channel 1142. It can be understood that the discharge channel 1141 is parallel to the first direction, but the guide channel 1142 can be parallel to the first direction, or have an angle relationship with the first direction. In addition, different guide channels 1142 can have different directions, thereby reducing the difficulty of manufacturing. In addition, a discharge port is provided on the side of the guide channel 1142 away from the discharge channel 1141, so that the microfluidic chip 1 has a plurality of discharge ports, and the discharge port is connected to the discharge area 114 of the discharge liquid collection system 5.

[0071] Further, in some specific embodiments, the overall process of the detection method includes the following steps: the first step is to assemble the microfluidic chip 1 on a microscope equipped with a high-speed camera, the microscope is focused on the observation and counting area in the microchannel 11, and the high-speed camera classifies and records the number of particles flowing through this area. The second step is to start the test device, and use the automatic sampling system to introduce the sample fluid into the microfluidic chip 1 in order at a certain flow rate V1 (when measuring multiple sample fluids within a certain period of time, the multiple sample fluids are sorted in order and measured in sequence), and at the same time, a pure fluid is introduced at a flow rate V2 much higher than the sample fluid to form an extrusion flow. Under the influence of the extrusion flow, the larger particles in the sample fluid tend to maintain the original trajectory and remain in the middle of the channel, while the smaller particles tend to be pushed to the channel wall, and finally separation is achieved according to the different particle sizes, and enters different discharge channels 1141. The third step is that the micron particles in the sample fluid are recorded by the high-speed camera when they flow through the observation and counting area of ​​the discharge channel 1141. After image analysis, the number of micron particles flowing through multiple discharge channels 1141 is counted respectively. Since the micron particles flowing through each discharge channel 1141 have different particle size ranges, the particle size distribution of the sample micron particles can be finally obtained through analysis. In the fourth step, the micron particles in the sample fluid are separated and discharged from different discharge ports after detection, and then collected into different micropores of the porous plate, which can be used for subsequent more precise measurement and analysis. Combined with the electric translation stage 6, the position of the porous plate can be adjusted to continue collecting other sample discharge liquids, that is, to start the fifth step of operation. In the fifth step, use the automatic sampling system to introduce new samples to be tested, and start a new round of testing from the second step until all sample fluid tests are completed.

[0072] Furthermore, in some specific embodiments, the microfluidic chip 1 can be formed by bonding two transparent substrate layers. Figure 2 and Figure 7It should be noted that Figure 7 The figures of each step are structural cross-sectional views, and are simple schematic diagrams showing the direction from the inlet to the outlet in the microchannel 11. Figure 7 The specific structures and the connection relationship between the structures such as the sample flow channel 111, the separation channel 113 and the discharge area 114 in the microchannel 11 are briefly described. Specifically, the microchannel 11 can be processed and opened on the first substrate layer 10 by photolithography, soft photolithography, hot stamping and other methods, and then the first substrate layer 10 and the second substrate layer 20 are bonded.

[0073] The specific process may be: step 1, a plurality of through holes 101 penetrating the first substrate layer 10 and a plurality of connecting grooves 102 connected to the through holes 101 may be opened on the first substrate layer 10, wherein the plurality of through holes 101 may respectively form a first inlet 1111, a second inlet 1121 and a plurality of outlets, and the connecting grooves 102 may be used to combine with the second substrate layer 20 to form the remaining structure of the microchannel 11, for example, one of the connecting grooves 102 combined with the second substrate layer 20 may be used as the remaining structure of the sample flow channel 111 except the first inlet 1111; step 2, bonding the second substrate layer 20 and the first substrate layer 10 to finally form the microchannel 11 structure.

[0074] In this way, in the microchannel 11, the first inlet 1111, the second inlet 1121 and the multiple outlets are through holes 101 connected to the outside world, so that the microchannel 11 can be connected to the outside world at the first inlet 1111, the second inlet 1121 and the multiple outlets through Teflon or other conduits; and the remaining structure of the microchannel 11 is the internal connection groove 102 structure, which ultimately makes the microchannel 11 as a whole in a closed state.

[0075] In addition, illustratively, the length of the microfluidic chip 1 may be 50-60 mm, and the width may be 30-40 mm. Furthermore, the material of the transparent substrate layer may be polydimethylsiloxane (PDMS), quartz glass, polymethyl methacrylate (PMMA), or polycarbonate (PC).

[0076] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0077] The above is a description of the technical solution provided by the present invention. For those skilled in the art, according to the ideas of the embodiments of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A micron particle size distribution testing device, characterized in that: Including microfluidic chip and information acquisition and analysis unit; The microfluidic chip is provided with a microchannel; the microchannel comprises a sample flow channel, an extrusion flow channel, a separation channel and a discharge area; The extrusion flow channel is used to introduce pure fluid, and the sample flow channel is used to introduce sample fluid; the flow rate of the pure fluid is greater than the flow rate of the sample fluid; The sample flow channel, the separation channel and the discharge area are sequentially connected and arranged along a first direction, the extrusion flow channel is connected between the sample flow channel and the separation channel, and there is an angle relationship between the extrusion flow channel and the first direction; The flow area of ​​the separation channel is smaller than the flow area of ​​the sample flow channel; The discharge area includes a plurality of discharge channels arranged parallel to the first direction, and the plurality of discharge channels are arranged at intervals; The information acquisition and analysis unit is used to monitor the discharge area and to analyze the number of micron particles flowing through each of the discharge channels to obtain the micron particle size distribution information of the sample fluid; The sample flow channel includes a first outlet channel, the extrusion flow channel includes a second outlet channel, the first outlet channel is connected to the second outlet channel and both are connected to the separation channel, the ratio of the flow area of ​​the first outlet channel to the flow area of ​​the second outlet channel is between 0.986-1.014, and the ratio of the flow area of ​​the first outlet channel to the flow area of ​​the discharge channel is between 0.986-1.014; The testing device further comprises an injection system and a liquid transfer device. The injection system is connected to the sample flow channel to introduce a sample fluid; the liquid transfer device is connected to the extrusion flow channel to introduce a pure fluid.

2. The micron particle size distribution testing device according to claim 1, characterized in that: The information acquisition and analysis unit includes a microscope module, a camera module and an information processing module. The microscope module focuses on the discharge area and / or the microchannel. The camera module is used to perform image monitoring of the discharge area under the microscope module. The information processing module is used to analyze and count the micron particle size distribution information of the sample fluid based on the image monitoring results.

3. The micron particle size distribution testing device according to claim 1, characterized in that: The ratio of the flow rate of the sample fluid to the flow rate of the pure fluid is in the range of 0.006 to 0.

02.

4. The micron particle size distribution testing device according to claim 3, characterized in that: The flow rate of the sample fluid ranges from 0.0048 mL / min to 0.0072 mL / min, and the flow rate of the pure fluid ranges from 0.48 mL / min to 0.72 mL / min.

5. The micron particle size distribution testing device according to claim 1, characterized in that: The ratio of the transverse cross-sectional width w of the separation channel to the transverse cross-sectional width W of the sample flow channel is in the range of 0.3 to 0.

8.

6. The micron particle size distribution testing device according to claim 5, characterized in that: The transverse cross-sectional width w of the separation channel ranges from 100 μm to 150 μm, and the transverse cross-sectional width W of the sample flow channel ranges from 200 μm to 300 μm.

7. The micron particle size distribution testing device according to claim 1, characterized in that: The testing device further comprises a discharge liquid collection system, wherein the discharge liquid collection system comprises a plurality of collection areas corresponding one to one with the discharge channels, and the collection areas are connected to the discharge channels.

8. The micron particle size distribution testing device according to claim 7, characterized in that: The testing device also includes an electric translation stage, the discharge liquid collection system is mounted on the electric translation stage, the discharge liquid collection system includes a plurality of collection spaces arranged at intervals along the moving direction of the electric translation stage, and each of the collection spaces includes the plurality of collection areas.

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