Liquid viscosity detection device and method based on micro-fluidic chip

Abstract

The invention provides a liquid viscosity detection device and method based on a micro-fluidic chip, and belongs to the technical field of microfluidics, the device comprises a micro-fluidic chip, a pressure control module, a photoelectric detection module and a data processing module; the micro-fluidic chip is mainly used for droplet generation and comprises a substrate and a cover plate, the pressure control module is mainly used for controlling the inlet pressure of the micro-fluidic chip and ensuring stable pressure input, and comprises a micro-fluidic pressure pump and an airtight connecting device; the photoelectric detection module is mainly used for liquid drop frequency detection and comprises an optical fiber cable and a photoelectric sensor; and the data processing module is mainly used for processing the electric signal and converting frequency information into viscosity information, and comprises a single chip microcomputer and a display. According to the detection device provided by the invention, under the action of constant pressure, the two-phase fluid flows into the micro-fluidic chip, the liquid drops are generated at the T-shaped junction, and a fixed curve can be fitted by the liquid drop frequency and the dispersed phase fluid viscosity, so that the dispersed phase viscosity can be determined through the liquid drop generation frequency, and full-automatic instant detection of the fluid viscosity is realized.

Description

Technical Field

[0001] The invention belongs to the technical field of microfluidics, and relates to a liquid viscosity detection device and method based on a microfluidics chip. Background Art

[0002] Viscosity is an important physical parameter that describes the internal resistance of a fluid when it flows or deforms. It has very important scientific and engineering significance. In many practical applications, it is necessary to measure the viscosity of a sample. In industry, the viscosity of petroleum products, paints, polymers, and fermentation products is tested to improve production efficiency and economic benefits. In medical diagnosis, the viscosity of blood, plasma, cerebrospinal fluid, pleural fluid, and amniotic fluid is related to a series of diseases.

[0003] At present, there are many commercial viscosity testing instruments, whose main principles include vibration method, capillary method, falling ball method and rotation method. The existing traditional viscosity testing instruments are relatively mature, but the sample volume required is relatively large and the entire testing process takes a long time. In addition, in applications that require continuous measurement, the labor cost and sample consumption are too high. General viscosity characterization is limited to single-point measurement.

[0004] Microfluidic chip technology can achieve micro-quantification of samples and real-time viscosity detection. During the detection process, the sample dosage is at the microliter level, and the real-time viscosity detection can be completed by simply controlling the injection pressure through simple operations. The test results can be visualized and the professional requirements for personnel are reduced. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention proposes a liquid viscosity detection device and method based on a microfluidic chip. Under the condition of constant two-phase inlet pressure, a curve graph of discrete phase viscosity and droplet generation frequency is derived. The liquid viscosity detection device obtains the discrete phase viscosity by detecting the droplet generation frequency.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0007] A liquid viscosity detection device and method based on a microfluidic chip, the liquid viscosity detection device comprises a microfluidic chip, a pressure control module, a photoelectric detection module and a data processing module. The microfluidic chip is mainly used to generate droplets, and comprises a substrate 1 and a cover sheet 2, and the substrate 1 and the cover sheet 2 are bonded by gluing; the pressure control module is mainly used to control the inlet pressure of the microfluidic chip to ensure stable pressure input, and comprises an airtight connection device 3 and a microfluidic pressure pump 4; the photoelectric detection module is mainly used for droplet frequency detection, and comprises an optical fiber line group 5 and a photoelectric sensor 6; the data processing module is mainly used to process electrical signals and convert frequency information into viscosity information, and comprises a single-chip computer 7 and a display 8. The substrate 1 and cover 2 of the microfluidic chip are bonded together to form a whole, and are connected to the microfluidic pressure pump 4 through the airtight connection device 3 in the pressure control module. The optical fiber line group 5 in the photoelectric detection module is vertically fixed on the upper and lower sides of the microfluidic chip to transmit the light transmittance change to the photoelectric sensor 6. The data processing module receives the electrical signal change of the photoelectric sensor 6 through the single-chip microcomputer 7 and transmits it to the display 8 through the serial communication method. The details are as follows:

[0008] The substrate 1 is a plate-like structure, on which a continuous phase inlet pool 9, a discrete phase inlet pool 10, a drainage pool 11, a serpentine flow channel 12 and a T-shaped flow channel 13 are arranged. Specifically, the continuous phase inlet pool 9 is connected to the entrance of the serpentine flow channel 12, the end of the serpentine flow channel 12 is connected to the entrance of the main flow channel of the T-shaped flow channel 13, the end of the main flow channel of the T-shaped flow channel 13 is connected to the drainage pool 11, and the side flow channel of the T-shaped flow channel is connected to the discrete phase inlet pool 10. The continuous phase liquid enters the serpentine flow channel 12 through the continuous phase inlet pool 9 and then enters the main flow channel of the T-shaped flow channel 13, and the discrete phase liquid enters the side flow channel of the T-shaped flow channel 13 through the discrete phase inlet pool 10, and the two-phase fluid generates droplets at the intersection of the main flow channel and the side flow channel of the T-shaped flow channel 13.

[0009] The cover sheet 2 is a plate-like structure, on which a continuous phase liquid inlet hole 14, a discrete phase liquid inlet hole 15 and a drainage hole 16 are provided; after the substrate 1 and the cover sheet 2 are bonded by gluing, the continuous phase fluid can enter the continuous phase liquid inlet pool 9 through the continuous phase liquid inlet hole 14, the discrete phase liquid can enter the discrete phase liquid inlet pool 10 through the discrete phase liquid inlet hole 15, and the waste liquid in the drainage pool 11 is discharged through the drainage hole 16.

[0010] The airtight connection device 3 includes a plastic tube 17, a continuous phase airtight liquid reservoir 18 and a discrete phase airtight liquid reservoir 19. The microfluidic pressure pump 4 has two independent pressure output channels, channel one 20 and channel two 21, which can stably output a pressure of 0-1 bar. Channel 1 20 is connected to the discrete phase airtight liquid reservoir 19 through a plastic tube 17, and the discrete phase airtight liquid reservoir 19 is connected to the discrete phase liquid inlet hole 15 of the microfluidic chip through the plastic tube 17. The liquid in the discrete phase airtight liquid reservoir 19 enters the discrete phase liquid inlet hole 15 of the microfluidic chip under the action of the constant pressure output by the microfluidic pressure pump 4; Channel 2 21 of the microfluidic pressure pump 4 is connected to the continuous phase airtight liquid reservoir 18 through a plastic tube 17, and the continuous phase airtight liquid reservoir 18 is connected to the continuous phase liquid inlet hole 14 of the microfluidic chip through the plastic tube 17. The liquid in the continuous phase airtight liquid reservoir 18 enters the continuous phase liquid inlet hole 14 of the microfluidic chip under the action of the constant pressure output by the microfluidic pressure pump 4.

[0011] The optical fiber line group 5 includes a single-core optical fiber line 22 and a multi-core optical fiber line 23, and the photoelectric sensor 6 includes an infrared light emitting end 24, an infrared light receiving end 25 and a photoelectric signal conversion module 26. The single-core optical fiber line 22 can focus the light diameter to 0.5 mm, the multi-core optical fiber line 23 is used to receive the focused light, the infrared light emitting end 24 has a built-in 625nm red light as a light source, the infrared light receiving end 25 has a built-in photosensitive element for detecting the amount of light received, and the electrical signal conversion module 26 can convert the optical signal into an electrical signal and transmit it to the single-chip computer 7. The single-core optical fiber line 22 is connected to the infrared light emitting end 24 and focuses the diameter of the light emitted by the infrared light emitting end 24 to 0.5 mm, the multi-core optical fiber line 23 is connected to the infrared light receiving end 25, receives the focused light and transmits the light to the infrared light receiving end 25, the infrared light receiving end 25 transmits the optical signal to the electrical signal conversion module 26, and the electrical signal conversion module 26 converts the received optical signal into an electrical signal. When the colorless continuous phase fluid passes through the optical fiber group 5, the infrared light receiving end 25 can receive the red light with a wavelength of 625mm emitted by the infrared light emitting end 24. When the dyed discrete phase passes through the optical fiber head, it will block the light from the infrared light emitting end 24, and the amount of light received by the infrared light receiving end 25 will decrease. Based on the change in the amount of light received, it can be determined whether there are droplets passing by.

[0012] The single chip microcomputer 7 and the photoelectric sensor 6 are connected by wires. The single chip microcomputer 7 receives the electrical signal from the photoelectric sensor 6, and can calculate the number of droplets and the droplet generation frequency through the change of the electrical signal, and then calculate the discrete phase viscosity according to the relationship between the droplet generation frequency and the discrete phase viscosity, wherein the relationship between the droplet generation frequency and the discrete phase viscosity is shown in Formula I:

[0013]

[0014] Among them, α and β are constants that are only related to the microfluidic chip structure and input pressure; η represents the discrete viscosity; and f represents the droplet generation frequency.

[0015] The display 8 receives the viscosity information of the discrete phase in the single chip computer 7 through serial communication and displays it.

[0016] A liquid viscosity detection device and method based on a microfluidic chip, comprising the following steps:

[0017] Step 1, take 1 ml of the dyed discrete phase liquid and add it into the discrete phase airtight liquid reservoir 19, take 1 ml of the colorless continuous phase liquid and add it into the continuous phase airtight liquid reservoir 18.

[0018] Step 2: Connect all devices, check the air tightness of the devices, and turn on the power of all equipment.

[0019] Step 3, regulating the output pressure of channel 1 20 and channel 2 21 of the microfluidic pressure pump 4, controlling channel 1 20 to stably output a pressure of 30 mbar and channel 2 21 to stably output a pressure of 50 mbar.

[0020] Step 4, under the action of the pressure output by channel 1 20 and channel 2 21 of the microfluidic pressure pump 4, the dyed discrete phase liquid in the discrete phase airtight liquid reservoir 19 flows into the discrete phase liquid inlet hole 15 through the plastic tube 17, enters the discrete phase liquid inlet pool 10, and then flows into the side channel of the T-type flow channel 13. The colorless continuous phase liquid in the continuous phase airtight liquid reservoir 18 flows into the continuous phase liquid inlet hole 14 through the plastic tube 17, enters the continuous phase liquid inlet pool 9, and flows into the main channel of the T-type flow channel 13 through the serpentine flow channel 12. The dyed discrete phase liquid and the colorless continuous phase liquid meet at the intersection of the main channel and the side channel of the T-type flow channel 13. Under the combined action of interfacial tension, shear stress and pressure difference, the dyed discrete phase liquid enters the main channel and generates discrete phase droplets under the extrusion of the colorless continuous phase liquid. The droplets flow into the downstream of the main channel of the T-type flow channel 13 wrapped in the colorless continuous phase liquid. All the liquids finally flow into the drainage pool 11 and are discharged through the drainage hole 16.

[0021] Step 5, the 625nm red light emitted by the infrared light emitting end 24 is focused by the single-core optical fiber line 22 and then received by the multi-core optical fiber line 23, and the multi-core optical fiber line 23 then transmits the received red light to the infrared light receiving end 25; when the colorless continuous phase liquid passes through the optical fiber line group 5, the infrared light receiving end 25 can receive the 625nm red light emitted by the infrared light emitting end 24, and when the dyed discrete phase liquid passes through the optical fiber line group 5, the 625nm red light emitted by the infrared light emitting end 24 is blocked, and the amount of light received by the infrared light receiving end 25 is reduced. Therefore, the electrical signal conversion module 26 can determine whether there are discrete phase droplets passing according to the change in the amount of light received by the infrared light receiving end 25 and output a corresponding electrical signal. When the amount of light received is greater than the set threshold, the electrical signal conversion module 26 outputs a high level, and when it is lower than the set threshold, the electrical signal conversion module 26 outputs a low level. Therefore, when droplets pass, the electrical signal conversion module 26 outputs a low level, and when no droplets pass, the electrical signal conversion module 26 outputs a high level.

[0022] Step 6, the electrical signal conversion module 26 transmits the electrical signal change to the single-chip microcomputer 7, and the single-chip microcomputer 7 can calculate the droplet generation frequency by processing the electrical signal. Specifically: when the droplet passes through the optical fiber line group 5, the electrical signal received by the single-chip microcomputer 7 changes from a high level to a low level, generating a falling edge. The single-chip microcomputer 7 calculates the number of droplets generated by edge counting. Combined with the timer in the single-chip microcomputer 7, the single-chip microcomputer 7 can calculate the droplet generation frequency, and the droplet generation frequency is brought into Formula I to calculate the discrete phase viscosity. The single-chip microcomputer 7 transmits the viscosity data to the display 8 through serial communication. At this point, the discrete phase viscosity detection is completed.

[0023] The beneficial effects of the present invention are:

[0024] A new viscosity detection method is proposed. Based on the droplet generation frequency, the viscosity of discrete phases is detected. The liquid viscosity can be detected in a short time and the sample amount can be controlled at the microliter level.

[0025] Highly integrated, fully automatic detection. This device integrates droplet generation, frequency detection, and viscosity calculation. The viscosity result can be obtained after adding the sample, without the need for professional operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a side view of a microfluidic chip of a liquid viscosity detection device and method based on a microfluidic chip of the present invention.

[0027] Figure 2 It is a schematic diagram of a liquid viscosity detection device and method based on a microfluidic chip of the present invention.

[0028] Figure 3 It is a top view of a microfluidic chip of a liquid viscosity detection device and method based on a microfluidic chip of the present invention.

[0029] Figure 4 It is a schematic diagram of a liquid viscosity detection device and method based on a microfluidic chip of the present invention.

[0030] Figure 5 The present invention is a relationship diagram between the droplet generation frequency and the viscosity of the discrete phase droplet of a liquid viscosity detection device and method based on a microfluidic chip; wherein a is a curve showing the change of the droplet generation frequency with the viscosity of the discrete phase solution; b is a curve showing the change of the inverse of the droplet generation frequency with the viscosity of the discrete phase solution, and the slope after linear fitting in the figure is α, and the intercept is β.

[0031] Explanation of the reference numerals: 1 substrate; 2 cover plate; 3 airtight connection device; 4 microfluidic pressure pump; 5 optical fiber line group; 6 photoelectric sensor; 7 single-chip computer; 8 display; 9 continuous phase liquid inlet tank; 10 discrete phase liquid inlet tank; 110 liquid discharge tank; 12 serpentine flow channel; 13 T-type flow channel 14 continuous phase liquid inlet hole; 15 discrete phase liquid inlet hole; 16 liquid discharge hole; 17 plastic tube; 18 continuous phase airtight liquid storage tank; 19 discrete phase airtight liquid storage tank; 20 channel one; 21 channel two; 22 single-core optical fiber line; 23 multi-core optical fiber line; 24 infrared light emitting end; 25 infrared light receiving end; 26 electrical signal conversion module. DETAILED DESCRIPTION

[0032] The present invention is further described in detail below in conjunction with an example of blood viscosity detection so that those skilled in the art can implement the invention with reference to the description.

[0033] Unless otherwise specified, the methods used in the following technical schemes are all conventional methods. The materials and reagents used in the following technical schemes can be obtained through commercial channels.

[0034] The present example implements a liquid viscosity detection device and method based on a microfluidic chip, which includes a microfluidic chip, a pressure control module, a photoelectric detection module and a data processing module.

[0035] The microfluidic chip is mainly used for droplet generation, including a substrate 1 and a cover sheet 2. The substrate 1 and the cover sheet 2 are made of PMMA, and flow channels are processed thereon by micro-milling, and holes are punched, and then the substrate 1 and the cover sheet 2 are bonded by gluing. Specifically, the substrate 1 is provided with a continuous phase inlet pool 9 with a diameter of 3 mm and a depth of 1 mm, a discrete phase inlet pool 10 with a diameter of 3 mm and a depth of 1 mm, a drainage pool 11 with a diameter of 3 mm and a depth of 1 mm, a serpentine flow channel 12 with a length of 300 mm, a width of 1 mm and a depth of 1 mm, and a serpentine flow channel 12 with a width of 1 mm and a depth of 1 mm. The continuous phase inlet pool 9 is connected to the entrance of the serpentine flow channel 12, the end of the serpentine flow channel 12 is connected to the entrance of the main flow channel of the T-type flow channel 13, the end of the main flow channel of the T-type flow channel 13 is connected to the drainage pool 11, and the side flow channel of the T-type flow channel is connected to the discrete phase inlet pool 10. The continuous phase liquid enters the serpentine flow channel 12 through the continuous phase inlet pool 9 and then enters the main channel of the T-type flow channel 13, and the dispersed phase liquid enters the side channel of the T-type flow channel 13 through the dispersed phase inlet pool 10, and the two-phase fluid generates droplets at the intersection of the main channel and the side channel of the T-type flow channel 13. The cover sheet 2 is provided with a continuous phase inlet hole 14 with a diameter of 2mm, a dispersed phase inlet hole 15 with a diameter of 2mm, and a drainage hole 16 with a diameter of 2mm. The continuous phase fluid can enter the continuous phase inlet pool 9 through the continuous phase inlet hole 14, and the dispersed phase liquid can enter the dispersed phase inlet pool 10 through the dispersed phase inlet hole 15, and the waste liquid in the drainage pool 11 is discharged through the drainage hole 16.

[0036] The pressure control module is mainly used to control the inlet pressure of the microfluidic chip to ensure stable pressure input, including an airtight connection device 3 and a microfluidic pressure pump 4. The photoelectric detection module is mainly used for droplet frequency detection, including an optical fiber line group 5 and a photoelectric sensor 6. The data processing module is mainly used to process electrical signals and convert frequency information into viscosity information, including a single-chip microcomputer 7 and a display 8. The inlet of the microfluidic chip is connected to the microfluidic pressure pump 4 through the airtight connection device 3 in the pressure control module. The optical fiber line group 5 in the photoelectric detection module is vertically fixed on the upper and lower sides of the microfluidic chip to transmit the transmittance change to the photoelectric sensor 6. The data processing module receives the electrical signal change of the photoelectric sensor 6 through the single-chip microcomputer 7, and transmits it to the display 8 through serial communication.

[0037] Based on the above system, a liquid viscosity detection device and method based on a microfluidic chip includes the following steps:

[0038] Step 1, select white clay-cephalin suspension as a coagulant, take 0.4 ml of the coagulant and add it to the discrete phase airtight liquid reservoir 19, take 1 ml of colorless dimethyl silicone oil and add it to the continuous phase airtight liquid reservoir 18, wherein the viscosity of the dimethyl silicone oil is 18.08 mm 2 / s.

[0039] Step 2, add 1 ml of fresh rabbit whole blood to 0.4 ml of coagulant, place the discrete phase airtight reservoir 19 in a 37°C water bath, connect all pipes, check the airtightness of the airtight connection device 3 and the microfluidic pressure pump 4, and turn on the power of all equipment.

[0040] Step 3, regulating the output pressures of channel 1 20 and channel 2 21 of the microfluidic pressure pump 4, controlling channel 1 20 to stably output a pressure of 30 mbar and channel 2 21 to stably output a pressure of 50 mbar.

[0041] Step 4, under the action of the pressure output from channel 1 20 and channel 2 21 of the microfluidic pressure pump 4, the whole rabbit blood mixed with the coagulant in the discrete phase airtight reservoir 19 flows into the discrete phase inlet hole 15 through the plastic tube 17, enters the discrete phase inlet pool 10, and then flows into the side channel of the T-shaped flow channel 13, and the colorless dimethyl silicone oil solution in the continuous phase airtight reservoir 18 flows into the continuous phase inlet hole 14 through the plastic tube 17, enters the continuous phase inlet pool 9, and flows into the T-shaped flow channel through the serpentine flow channel 12 The rabbit whole blood mixed with the coagulant and the colorless dimethyl silicone oil solution meet at the intersection of the main channel and the side channel of the T-shaped flow channel 13. Under the combined action of interfacial tension, shear stress and pressure difference, the rabbit whole blood mixed with the coagulant enters the main channel and generates rabbit whole blood droplets under the extrusion of the colorless dimethyl silicone oil solution. The rabbit whole blood droplets are wrapped in the colorless dimethyl silicone oil solution and flow into the downstream of the T-shaped flow channel 13. At this time, the rabbit whole blood is a discrete phase and the dimethyl silicone oil solution is a continuous phase.

[0042] Step 5, the 625nm red light emitted by the infrared light emitting end 24 is focused by the single-core optical fiber line 22 and then received by the multi-core optical fiber line 23, and the multi-core optical fiber line 23 then transmits the received red light to the infrared light receiving end 25; when the colorless dimethyl silicone oil solution passes through the optical fiber line group 5, the infrared light receiving end 25 can normally receive the 625nm red light emitted by the infrared light emitting end 24. When the rabbit whole blood drop passes through the optical fiber line group 5, the 625nm red light emitted by the infrared light emitting end 24 is blocked, and the amount of light received by the infrared light receiving end 25 is reduced. Therefore, the electrical signal conversion module 26 can determine whether there is a droplet passing according to the change in the amount of light received by the infrared light receiving end 25 and output a corresponding electrical signal. When the amount of light received is greater than the set threshold, the electrical signal conversion module 26 outputs a high level, and when it is lower than the set threshold, the electrical signal conversion module 26 outputs a low level. Therefore, when no droplet passes, the electrical signal conversion module 26 outputs a high level, and when a droplet passes, the electrical signal conversion module 26 outputs a low level.

[0043] Step 6, the electrical signal conversion module 26 transmits the electrical signal change to the single-chip microcomputer 7, and the single-chip microcomputer 7 can calculate the droplet generation frequency by processing the electrical signal. Specifically: when the droplet passes through the optical fiber line group 5, the electrical signal received by the single-chip microcomputer 7 changes from a high level to a low level, generating a falling edge. The single-chip microcomputer 7 calculates the number of droplets generated by edge counting. Combined with the timer in the single-chip microcomputer 7, the single-chip microcomputer 7 can calculate the droplet generation frequency and bring the droplet generation frequency into Formula I (for the above experimental conditions, it can be concluded that α in Formula I is 0.0186 and β is 0.2211), and the discrete phase viscosity is calculated. The single-chip microcomputer 7 transmits the discrete phase viscosity data to the display 8 through serial communication, thereby realizing blood viscosity detection.

[0044] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A liquid viscosity detection device and method based on a microfluidic chip, characterized in that: The liquid viscosity detection device comprises a microfluidic chip, a pressure control module, a photoelectric detection module and a data processing module; The microfluidic chip is used to generate droplets, and comprises a substrate (1) and a cover sheet (2) bonded to the substrate (1); the pressure control module is used to control the inlet pressure of the microfluidic chip, and comprises an airtight connection device (3) and a microfluidic pressure pump (4); the photoelectric detection module is used to detect the frequency of droplets, and comprises an optical fiber line group (5) and a photoelectric sensor (6); the data processing module is used to process electrical signals, and comprises a single-chip computer (7) and a display (8); the microfluidic chip is connected to the microfluidic pressure pump (4) through the airtight connection device (3) in the pressure control module, the optical fiber line group (5) in the photoelectric detection module is vertically fixed on the upper and lower sides of the microfluidic chip, and transmits the transmittance change to the photoelectric sensor (6); the single-chip computer (7) of the data processing module receives the electrical signal change of the photoelectric sensor (6), converts it into viscosity information, and then transmits it to the display (8).

2. A liquid viscosity detection device based on a microfluidic chip according to claim 1, characterized in that: The substrate (1) is provided with a continuous phase liquid inlet pool (9), a discrete phase liquid inlet pool (10), a liquid drainage pool (11), a serpentine flow channel (12), and a T-shaped flow channel (13); the continuous phase liquid in the continuous phase liquid inlet pool (9) enters the main flow channel of the T-shaped flow channel (13) through the serpentine flow channel (12), and the discrete phase liquid in the discrete phase liquid inlet pool (10) enters the side flow channel of the T-shaped flow channel (13), and the two-phase fluid generates droplets at the intersection of the main flow channel and the side flow channel of the T-shaped flow channel (13); the main flow channel of the T-shaped flow channel (13) is connected to the liquid drainage pool (11); The cover sheet (2) is provided with a continuous phase liquid inlet hole (14), a discrete phase liquid inlet hole (15) and a liquid discharge hole (16); after the substrate (1) and the cover sheet (2) are bonded by gluing, the continuous phase fluid enters the continuous phase liquid inlet pool (9) through the continuous phase liquid inlet hole (14), the discrete phase liquid enters the discrete phase liquid inlet pool (10) through the discrete phase liquid inlet hole (15), and the waste liquid in the liquid discharge pool (11) is discharged through the liquid discharge hole (16).

3. A liquid viscosity detection device based on a microfluidic chip according to claim 2, characterized in that: The airtight connection device (3) comprises a plastic tube (17), a continuous phase airtight liquid reservoir (18) and a discrete phase airtight liquid reservoir (19), and the microfluidic pressure pump (4) has two independent pressure output channels, channel one (20) and channel two (21); The channel 1 (20) is connected to the discrete phase airtight liquid reservoir (19) through a plastic tube (17), the discrete phase airtight liquid reservoir (19) is connected to the discrete phase liquid inlet hole (15) of the microfluidic chip through the plastic tube (17), and the liquid in the discrete phase airtight liquid reservoir (19) enters the discrete phase liquid inlet hole (15) through a microfluidic pressure pump (4); The second channel (21) is connected to the continuous phase airtight liquid reservoir (18) via a plastic tube (17), the continuous phase airtight liquid reservoir (18) is connected to the continuous phase liquid inlet hole (14) of the microfluidic chip via the plastic tube (17), and the liquid in the continuous phase airtight liquid reservoir (18) enters the continuous phase liquid inlet hole (14) via a microfluidic pressure pump (4).

4. The liquid viscosity detection device based on a microfluidic chip according to claim 3 is characterized in that: The optical fiber line group (5) comprises a single-core optical fiber line (22) and a multi-core optical fiber line (23); the photoelectric sensor (6) comprises an infrared light emitting end (24), an infrared light receiving end (25) and a photoelectric signal conversion module (26); the single-core optical fiber line (22) is used to focus the light to a diameter of 0.5 mm, and is connected to the infrared light emitting end (24); the multi-core optical fiber line (23) is used to receive the focused light, and is connected to the infrared light emitting end (24); the infrared light emitting end (24) serves as a light source; the infrared light receiving end (25) is used to detect the amount of light received, and transmit the optical signal to the electrical signal conversion module (26); the electrical signal conversion module (26) converts the optical signal into an electrical signal and transmits it to the single-chip microcomputer (7); When the colorless continuous phase fluid passes through the optical fiber line group (5), the infrared light receiving end (25) receives the red light emitted by the infrared light emitting end (24). When the dyed discrete phase passes through the optical fiber head, it blocks the light from the infrared light emitting end (24), and the amount of light received by the infrared light receiving end (25) decreases. Whether a droplet has passed is determined based on the change in the amount of light received.

5. A liquid viscosity detection method based on a microfluidic chip, implemented based on the detection device according to any one of claims 1 to 4, characterized in that: The following steps are involved: Step 1, adding the dyed discrete phase liquid into the discrete phase airtight liquid reservoir (19), and adding the colorless continuous phase liquid into the continuous phase airtight liquid reservoir (18); Step 2, connect all devices, check the air tightness of the devices, and turn on the power of all devices; Step 3, regulating the output pressure of channel 1 (20) and channel 2 (21) of the microfluidic pressure pump (4), controlling channel 1 (20) to stably output a pressure of 30 mbar and channel 2 (21) to stably output a pressure of 50 mbar; Step 4, under the action of the pressure output from channel 1 (20) and channel 2 (21) of the microfluidic pressure pump (4), the dyed discrete phase liquid and the colorless continuous phase liquid meet at the intersection of the main channel and the side channel of the T-shaped channel (13). At this time, the dyed discrete phase liquid enters the main channel and generates discrete phase droplets. The discrete phase droplets flow into the downstream of the main channel of the T-shaped channel (13) while being wrapped by the colorless continuous phase liquid. All the liquid finally flows into the drainage pool (11) and is discharged through the drainage hole (16); Step 5, the infrared light emitting end (24) emits red light which is focused by the single-core optical fiber (22) and then received by the multi-core optical fiber (23), and the multi-core optical fiber (23) transmits the received red light to the infrared light receiving end (25); when the colorless continuous phase liquid passes through the optical fiber group (5), the infrared light receiving end (25) receives the red light emitted by the infrared light emitting end (24); when the dyed discrete phase liquid passes through the optical fiber group (5), the red light emitted by the infrared light emitting end (24) is blocked, and the infrared light receiving end (25) receives the red light emitted by the infrared light emitting end (24). The amount of light received by the receiving end (25) decreases, so the electrical signal conversion module (26) can determine whether there are discrete phase droplets passing through according to the change in the amount of light received by the infrared light receiving end (25) and output a corresponding electrical signal. When the amount of light received is greater than a set threshold, the electrical signal conversion module (26) outputs a high level, and when it is lower than the set threshold, the electrical signal conversion module (26) outputs a low level. Therefore, when there are droplets passing through, the electrical signal conversion module (26) outputs a low level, and when there are no droplets passing through, the electrical signal conversion module (26) outputs a high level. Step 6, the electrical signal conversion module (26) transmits the electrical signal change to the single chip microcomputer (7), and the single chip microcomputer (7) can calculate the droplet generation frequency by processing the electrical signal. Specifically: when the droplet passes through the optical fiber line group (5), the electrical signal received by the single chip microcomputer (7) changes from a high level to a low level, generating a falling edge, and the single chip microcomputer (7) calculates the number of droplet generation by edge counting. Combined with the timer in the single chip microcomputer (7), the single chip microcomputer (7) can calculate the droplet generation frequency, and the droplet generation frequency is brought into Formula I to calculate the discrete phase viscosity, and the viscosity data is displayed by the display (8); wherein, the relationship between the droplet generation frequency and the discrete phase viscosity is shown in Formula I: Among them, α and β are constants that are only related to the microfluidic chip structure and input pressure; η represents the discrete phase viscosity; and f represents the droplet generation frequency.

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