Preparation system and preparation method of electrochemical micro-fluidic chip

Abstract

The invention belongs to the technical field of chips, and particularly relates to a preparation system and a preparation method of an electrochemical micro-fluidic chip, the preparation system comprises a first conveyor, the first conveyor is used for continuously conveying chips on an electrochemical micro-fluidic chip automatic production line for preparation; a plurality of pressing and covering discs are arranged to synchronously package a plurality of electrochemical micro-fluidic chips which are being conveyed in a non-stop manner, so that a traditional manner of sequentially packaging a single electrochemical micro-fluidic chip in an intermittent stop manner is replaced, and the packaging efficiency of the electrochemical micro-fluidic chips is improved; the two opposite guide plates are used for guiding the conveyed electrochemical micro-fluidic chip, the conveying deviation prevention effect on the electrochemical micro-fluidic chip is achieved, sliding plates on the guide plates slide on the inner wall of a first fixing frame, the position of the sliding plates is fixed through cooperation of limiting rods, the distance between the two guide plates can be adaptively adjusted, and the conveying deviation prevention effect on the electrochemical micro-fluidic chip is achieved. The method is suitable for preparing different types of electrochemical micro-fluidic chips.

Description

Technical Field

[0001] The invention belongs to the technical field of chips, and in particular relates to a preparation system and a preparation method of an electrochemical microfluidic chip. Background Art

[0002] Microfluidic chip technology utilizes fluid control in micron- or nanoscale channels to achieve precise processing and analysis of samples. This technology has the advantages of small sample requirements, fast response speed and easy integration, and is widely used in biomedical testing and environmental monitoring.

[0003] A patent application with publication number CN115414971A discloses a method for preparing a micro-control flow chip and a micro-control flow chip. Polydimethylsiloxane (PDMS) monomer is mixed with a curing agent to obtain a PDMS mother liquor; the PDMS mother liquor is poured into a first silicon mold, heated and cured to obtain a first cured PDMS; the PDMS mother liquor is poured into a second silicon mold, spin coated, and heated and cured to obtain a second cured PDMS; compared with traditional laser and mechanical finishing technologies, the chip processed by this application has high precision and a simple method.

[0004] The above-mentioned microfluidic chip preparation technology has higher precision than traditional laser and mechanical finishing technology. However, when preparing large quantities of electrochemical microfluidic chips, current electrochemical microfluidic chips are usually packaged in sequence with intermittent shutdowns, resulting in a large number of electrochemical microfluidic chips being difficult to quickly seal after production, thereby affecting the preparation efficiency of electrochemical microfluidic chips.

[0005] To this end, the present invention provides a system and method for preparing an electrochemical microfluidic chip. Summary of the invention

[0006] In order to make up for the deficiencies of the prior art, at least one technical problem raised in the background technology is solved.

[0007] The technical solution adopted by the present invention to solve its technical problem is: the preparation system of an electrochemical microfluidic chip described in the present invention includes a No. 1 conveyor, which is used to continuously convey chip preparation on an electrochemical microfluidic chip automated production line; the No. 1 conveyor is sequentially installed with a No. 1 photolithography machine, a No. 2 photolithography machine, a preparation box and a packaging module, the preparation box is located on the side of the No. 2 photolithography machine away from the No. 1 photolithography machine, and the packaging module is used to package the finished electrochemical microfluidic chip.

[0008] Preferably, a No. 1 fixing frame is fixedly connected to a side of the No. 1 conveyor close to the preparation box; a support seat is fixedly connected to a side of the No. 1 fixing frame away from the preparation box, and the support seat is installed at the tail end of the No. 1 conveyor; the top of the No. 1 fixing frame is fixedly connected to the No. 1 fixing seat; the packaging module includes a pressure plate, a support frame, an electric slider, an electric cylinder and a connecting frame; the support frame is fixedly connected to the top of the No. 1 fixing seat; the electric slider is slidably connected to the bottom end of the support frame; the electric cylinder is fixedly connected to the middle bottom end of the electric slider; the connecting frame is fixedly connected to the output end of the electric cylinder; a plurality of the pressure plates are arranged horizontally and fixedly connected to the bottom end of the connecting frame.

[0009] Preferably, two sliding plates are relatively slidably connected to the No. 1 fixing frame; guide plates are fixedly connected to the outer walls of the two sliding plates, and the guide plates are slidably connected to the inner wall of the No. 1 fixing frame.

[0010] Preferably, a plurality of limiting holes are provided on the two sliding plates; two fixing plates are relatively fixedly connected to the No. 1 fixing frame, and the fixing plates are located above the sliding plates; limiting rods are inserted through the fixing plates, and the limiting rods are inserted into the limiting holes.

[0011] Preferably, a No. 2 fixing frame is fixedly connected to the side of the support seat away from the No. 1 fixing frame; a No. 2 conveyor is installed between the No. 2 fixing frame and the support seat; an arc-shaped plate is fixedly connected to the outer wall of the support seat, the arc-shaped plate is located at the end of the No. 1 conveyor and above the No. 2 conveyor, and a sliding groove is opened inside the arc-shaped plate; a No. 2 fixing frame is fixedly connected to the support seat, and a second group of packaging modules is installed on the No. 2 fixing frame.

[0012] Preferably, an extrusion box is fixedly connected to the outer wall of the support frame; an extrusion rod is slidably connected to the inner wall of the extrusion box; an extrusion plate is fixedly connected to one end of the extrusion rod located inside the extrusion box, and the extrusion plate is slidably connected to the inside of the extrusion box; a No. 1 air duct is fixedly connected to the inside of the extrusion box; a guide box is fixedly connected to the outer wall of the extrusion box near the No. 1 air duct through the exhaust pipe; an elastic part is fixedly connected between the inner wall of the extrusion box and the outer wall of the extrusion plate.

[0013] Preferably, a No. 2 air duct is fixedly connected to the interior of the extrusion box; an air inlet is opened inside the extrusion box close to the extrusion rod; and a one-way valve is fixedly connected to the No. 1 air duct, the No. 2 air duct and the air inlet.

[0014] Preferably, an assembly frame is relatively fixedly connected to the support seat and the second fixing frame; and a pressure roller is rotatably connected between the two assembly frames.

[0015] A method for preparing an electrochemical microfluidic chip, the method is applicable to the electrochemical microfluidic chip preparation system described above for processing, and the method steps are as follows:

[0016] S1: First, multiple electrochemical microfluidic chip substrates are sequentially placed on conveyor No. 1 for transportation. When the electrochemical microfluidic chip substrates pass through the interior of photolithography machine No. 1, photolithography machine No. 1 uses photolithography technology to manufacture microfluidic channels on the electrochemical microfluidic chip substrates. Then, photolithography machine No. 2 uses micro-electromechanical system MEMS technology to integrate electrochemical electrodes in the microfluidic channels.

[0017] S2: The electrochemical microfluidic chip is then sent to a preparation box to modify the surface of magnetic beads with anti-Salmonella typhimurium and anti-Escherichia coli antibodies;

[0018] S3: After the inspection, the electrochemical microfluidic chip is then sent to the No. 1 fixing rack, and a plurality of pressing plates with packaging films are respectively pressed on a plurality of finished electrochemical microfluidic chips. The top surface of the electrochemical microfluidic chip is firstly laminated. As the electrochemical microfluidic chip is continuously transported, the laminated electrochemical microfluidic chip is turned over to the other side and laminated again, thereby completing the preparation of the electrochemical microfluidic chip.

[0019] Preferably, the microfluidic channel material described in S1 is polydimethylsiloxane; the electrochemical electrode integrated on the microfluidic channel is used to detect electrochemical signals, and the electrochemical electrode is made of one of gold, platinum and carbon materials; the electrochemical microfluidic chip is provided with sodium alginate gel microspheres, and the surface is modified with antibodies that specifically bind to target bacteria; one of the pressing plates with a packaging film first presses one side of the electrochemical microfluidic chip, and as the arc plate guides and flips the electrochemical microfluidic chip, another pressing plate with a packaging film presses the other side of the electrochemical microfluidic chip to complete the packaging.

[0020] The beneficial effects of the present invention are as follows:

[0021] 1. The preparation system and preparation method of an electrochemical microfluidic chip described in the present invention, through the provision of multiple pressing plates, multiple electrochemical microfluidic chips being transported are packaged synchronously without stopping, replacing the traditional method of intermittently stopping and sequentially packaging a single electrochemical microfluidic chip, thereby improving the efficiency of electrochemical microfluidic chip packaging, and utilizing two relative guide plates to guide the electrochemical microfluidic chip being transported, thereby preventing the electrochemical microfluidic chip from being deviated during transportation, and the sliding plate on the guide plate slides on the inner wall of the No. 1 fixed frame, and the position of the sliding plate is fixed by the limit rod, and the distance between the two guide plates can be adaptively adjusted, so that it is suitable for the preparation of electrochemical microfluidic chips of different models, and utilizing arc plates to be arranged at the head and tail of the two conveyors, so that the electrochemical microfluidic chip can be quickly turned over, thereby achieving the effect of double-sided packaging of the electrochemical microfluidic chip.

[0022] 2. The system and method for preparing an electrochemical microfluidic chip described in the present invention slide and squeeze the extrusion rod through an electric slider, so that the extrusion plate connected to the extrusion rod squeezes the gas inside the extrusion box to discharge it, and uses the squeezed gas to air-cool the electrochemical microfluidic chip that has just been separated from the pressing plate, thereby reducing the damage to the electrochemical microfluidic chip caused by the heat of the packaging film. The gas in the extrusion box is squeezed again to be discharged during the resetting process of the extrusion plate, thereby continuously cooling the chip during the reciprocating movement of the extrusion plate. The conveyed electrochemical microfluidic chip is compacted by a pressure roller, thereby reducing the occurrence of bubbling on the surface of the electrochemical microfluidic chip.

[0023] 3. The preparation system and preparation method of an electrochemical microfluidic chip described in the present invention have the following advantages: high sensitivity and high specificity: by using magnetic beads modified with specific antibodies and sodium alginate gel microspheres, target bacteria can be efficiently captured and detected, significantly improving the sensitivity and specificity of detection; rapid detection: the entire bacterial separation, enrichment and detection process is simultaneously realized on a microfluidic chip integrated with electrochemical electrodes, greatly shortening the detection time; multiple detection: the signals obtained through different electrochemical potentials can realize the simultaneous detection of multiple target bacteria, thereby improving the detection efficiency; wide application: this technology can be widely used in food safety testing, medical diagnosis, environmental monitoring and other fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention will be further described below in conjunction with the accompanying drawings.

[0025] Figure 1 is a stereogram of the present invention;

[0026] Figure 2 It is a structural schematic diagram of the pressure roller in the present invention;

[0027] Figure 3 It is a structural schematic diagram of the guide plate in the present invention;

[0028] Figure 4 It is a structural schematic diagram of the connecting frame in the present invention;

[0029] Figure 5 It is a partial structural cross-sectional view of the extrusion box in the present invention;

[0030] Figure 6 It is a structural schematic diagram of the curved plate in the present invention;

[0031] Figure 7 It is a structural schematic diagram of the sliding plate in the present invention;

[0032] Figure 8 is a flow chart of the method for preparing the electrochemical microfluidic chip of the present invention;

[0033] Fig. 9It is a schematic diagram of the structure of the electrochemical microfluidic chip of the present invention;

[0034] Fig.10 Schematic diagram of the capture and detection process of target bacteria of the present invention;

[0035] Fig.11 It is a flow chart of the bacteria detection method of the present invention.

[0036] In the figure: 1. Conveyor No. 1; 11. Photolithography machine No. 1; 12. Photolithography machine No. 2; 13. Preparation box; 14. Fixed frame No. 1; 15. Support seat; 16. Pressure plate; 2. Fixed seat No. 1; 21. Support frame; 22. Electric slide block; 23. Electric cylinder; 24. Connecting frame; 3. Sliding plate; 31. Guide plate; 4. Fixed plate; 41. Limit rod; 5. Fixed frame No. 2; 51. Conveyor No. 2; 52. Arc plate; 53. Fixed seat No. 2; 6. Extrusion box; 61. Extrusion rod; 62. Extrusion plate; 63. Air duct No. 1; 64. Guide box; 65. Elastic part; 7. Air duct No. 2; 71. Air inlet; 8. Assembly frame; 81. Pressure roller. DETAILED DESCRIPTION

[0037] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0038] like Figures 1 to 4 As shown, a preparation system of an electrochemical microfluidic chip described in an embodiment of the present invention comprises a No. 1 conveyor 1, which is used for continuously conveying chip preparation on an electrochemical microfluidic chip automated production line; a No. 1 photolithography machine 11, a No. 2 photolithography machine 12, a preparation box 13 and a packaging module are sequentially arranged on the No. 1 conveyor 1, the preparation box 13 is located on the side of the No. 2 photolithography machine 12 away from the No. 1 photolithography machine 11, and the packaging module is used for packaging finished electrochemical microfluidic chips; when preparing a large number of electrochemical microfluidic chips, the No. 1 conveyor 1 is used as a conveying tool for the electrochemical microfluidic chip substrate to convey the electrochemical microfluidic chip The electrochemical microfluidic chips are sent to multiple devices for processing with different processes. The No. 1 photolithography machine 11 can use photolithography technology to manufacture microfluidic channels on the substrate of the electrochemical microfluidic chip. The No. 2 photolithography machine 12 uses micro-electromechanical system MEMS technology to integrate electrochemical electrodes in the microfluidic channel. The preparation box 13 uses EDC / NHS coupling method to fix specific antibodies on the surface of magnetic beads. Finally, the packaging module cooperates with the No. 1 conveyor 1 to quickly package the finished electrochemical microfluidic chips in large quantities without stopping, which replaces the traditional intermittent shutdown and sequential packaging method of a single electrochemical microfluidic chip, thereby improving the efficiency of electrochemical microfluidic chip packaging.

[0039] A No. 1 fixed frame 14 is fixedly connected to one side of the No. 1 conveyor 1 close to the preparation box 13; a support seat 15 is fixedly connected to the side of the No. 1 fixed frame 14 away from the preparation box 13, and the support seat 15 is installed at the tail end of the No. 1 conveyor 1; the top of the No. 1 fixed frame 14 is fixedly connected to the No. 1 fixed seat 2; the packaging module includes a pressing plate 16, a support frame 21, an electric slider 22, an electric cylinder 23 and a connecting frame 24; the support frame 21 is fixedly connected to the top of the No. 1 fixed seat 2; the electric slider 22 is slidably connected to the bottom end of the support frame 21; the electric cylinder 23 is fixedly connected to the electric slider 2 ... The middle bottom end of the slider 22; the connecting frame 24 is fixedly connected to the output end of the electric cylinder 23; a plurality of the pressing plates 16 are arranged horizontally and fixedly connected to the bottom end of the connecting frame 24; when packaging a large number of electrochemical microfluidic chips, firstly, a large number of electrochemical microfluidic chip substrates are placed on the No. 1 conveyor 1 for transportation and processing. After the electrochemical microfluidic chip processing is completed, the No. 1 conveyor 1 conveys the finished electrochemical microfluidic chip to the position below the support frame 21 supported by the No. 1 fixing seat 2, and then the output end of the electric cylinder 23 drives the plurality of pressing plates with packaging films at the bottom end of the connecting frame 24. The covering plate 16 extends downward until the multiple pressing plates 16 press the packaging film onto the multiple electrochemical microfluidic chip products. The electric slider 22 drives the pressing plates 16 pressed onto the multiple electrochemical microfluidic chips to slide synchronously with the conveying speed of the No. 1 conveyor 1. The conveying speed of the No. 1 conveyor 1 is relatively slow. The conveying speed is slowed down to match the packaging speed. The conveying and packaging are carried out simultaneously, thereby improving the packaging effect of the electrochemical microfluidic chip, so that the packaging film can be kept under pressure for a distance on the electrochemical microfluidic chip, and then the output end of the electric cylinder 23 drives the multiple pressing plates 16 to lift up. The electric slider 22 drives the multiple pressing plates 16 to reset. During the resetting process of the multiple pressing plates 16, the film is moved to the bottom of the pressing plates 16 by a manipulator. Two groups of manipulators are provided. The two groups of manipulators are respectively installed on the sides of the two support frames 21. The manipulators are mainly used to pick up a new packaging film and stick it to the bottom of the pressing plate 16 after the pressing plate 16 presses the electrochemical microfluidic chip. The vacuum pump installed on the connecting frame 24 cooperates with the multiple pressing plates 16 to adsorb the packaging film respectively, and the electrochemical microfluidic chip is continuously packaged reciprocatingly, thereby improving the efficiency of packaging the electrochemical microfluidic chip.

[0040] like Figures 1 to 3 , Figure 7As shown, two sliding plates 3 are relatively slidably connected to the No. 1 fixed frame 14; the outer walls of the two sliding plates 3 are fixedly connected with guide plates 31, and the guide plates 31 are slidably connected to the inner wall of the No. 1 fixed frame 14; when the electrochemical microfluidic chip is packaged, since the No. 1 conveyor 1 is prone to shaking during transportation, the position of the electrochemical microfluidic chip is offset, and two relative guide plates 31 are placed at the end of the No. 1 conveyor 1. The two guide plates 31 can guide the conveying direction of the electrochemical microfluidic chip, so that the electrochemical microfluidic chip can be guided and transported to the bottom of multiple pressure plates 16 for packaging, which plays a role in preventing the electrochemical microfluidic chip from being deviated during transportation. At the same time, the sliding plate 3 on the guide plate 31 is slid on the inner wall of the No. 1 fixed frame 14, so that the distance between the two guide plates 31 can be adaptively adjusted, which is suitable for the preparation of electrochemical microfluidic chips of different models.

[0041] A plurality of limiting holes are provided on the two sliding plates 3; two fixing plates 4 are relatively fixedly connected to the No. 1 fixing frame 14, and the fixing plate 4 is located above the sliding plate 3; a limiting rod 41 is inserted through the fixing plate 4, and the limiting rod 41 is inserted into the limiting hole; when the two guide plates 31 are located on the No. 1 conveyor 1 to guide the transportation of the electrochemical microfluidic chip, the fixing plate 4 is fixed to the outer wall of the No. 1 fixing frame 14, and the limiting rod 41 is inserted through the fixing plate 4 into the limiting hole of the sliding plate 3, thereby limiting the position of the guide plate 31 and ensuring the stability of the two guide plates 31 in guiding the electrochemical microfluidic chip.

[0042] like Figures 1 to 3 , Figure 6As shown, a No. 2 fixing frame 5 is fixedly connected to the side of the support seat 15 away from the No. 1 fixing frame 14; a No. 2 conveyor 51 is installed between the No. 2 fixing frame 5 and the support seat 15; an arc plate 52 is fixedly connected to the outer wall of the support seat 15, and the arc plate 52 is located at the end of the No. 1 conveyor 1 and above the No. 2 conveyor 51, and a sliding groove is opened inside the arc plate 52; a No. 2 fixing seat 53 is fixedly connected to the support seat 15, and a second group of packaging modules is installed on the No. 2 fixing seat 53; after the top surface of the electrochemical microfluidic chip is packaged, the bottom surface of the electrochemical microfluidic chip needs to be packaged again, and the No. 2 fixing frame 5 cooperates with the support seat 15 to support the No. 2 conveyor 51, and a No. 2 fixing frame 53 is fixedly connected to the support seat 15, and a second group of packaging modules is installed on the No. 2 fixing seat 53. The electrochemical microfluidic chip after top surface packaging is transported on conveyor No. 1 to the arc plate 52, and the electrochemical microfluidic chip is received by the arc plate 52 with a sliding groove. The arc of the arc plate 52 is 75-80 degrees, and the electrochemical microfluidic chip slides down along the arc-shaped sliding groove to conveyor No. 2 51. The conveying directions of conveyors No. 1 and No. 2 51 are consistent, so that the electrochemical microfluidic chip can be quickly turned over and transported. Two relative guide plates 31 are also installed on the support seat 15. With the guidance of the two guide plates 31, the electrochemical microfluidic chip is transported to the second group of packaging modules for further packaging, which plays a role in double-sided packaging of the electrochemical microfluidic chip.

[0043] like Figures 1 to 5 As shown, the outer wall of the support frame 21 is fixedly connected with an extrusion box 6; the inner wall of the extrusion box 6 is slidably connected with an extrusion rod 61; one end of the extrusion rod 61 located inside the extrusion box 6 is fixedly connected with an extrusion plate 62, and the extrusion plate 62 is slidably connected to the inside of the extrusion box 6; the inside of the extrusion box 6 is fixedly connected with a No. 1 air duct 63; the outer wall of the extrusion box 6 is fixedly connected with a guide box 64 near the No. 1 air duct 63 through an exhaust pipe; an elastic member 65 is fixedly connected between the inner wall of the extrusion box 6 and the outer wall of the extrusion plate 62; when encapsulating the electrochemical microfluidic chip, it is necessary to press the packaging film with heat onto the electrochemical microfluidic chip, but the heat is conducted for a long time. The extrusion box 6 is fixed on the tail of the support frame 21, and the electric slider 22 can squeeze the extrusion rod 61 during sliding. The extrusion rod 61 drives the extrusion plate 62 to squeeze the gas inside the extrusion box 6, and the elastic member 65 is squeezed and contracted. Then the squeezed gas is sent to the guide box 64 through the No. 1 air duct 63 and the exhaust pipe for discharge. The guide box 64 is facing the electrochemical microfluidic chip being transported on the No. 1 conveyor 1, and the squeezed gas is used to cool the electrochemical microfluidic chip that has just left the pressure plate 16, so as to reduce the heat of the packaging film and cause damage to the electrochemical microfluidic chip.

[0044] The interior of the extrusion box 6 is fixedly connected with a No. 2 air duct 7; the interior of the extrusion box 6 near the extrusion rod 61 is provided with an air inlet 71; the No. 1 air duct 63, the No. 2 air duct 7 and the air inlet 71 are all fixedly connected with a one-way valve; when the electrochemical microfluidic chip that has just been filmed is air-cooled, the electric slider 22 slides and squeezes the extrusion rod 61, and the extrusion plate 62 squeezes the elastic member 65 to contract and bear the force, at this time, the one-way valves on the No. 2 air duct 7 and the air inlet 71 are in a closed state, and the one-way valve on the No. 1 air duct 63 is in an open state, and the extrusion plate 62 can squeeze the gas inside the extrusion box 6 through the No. 1 air duct 63 to the guide box 64 for external discharge, so as to air-cool the electrochemical microfluidic chip that has just been filmed, and then The electric slider 22 is reset, and the elastic force of the elastic member 65 drives the extrusion plate 62 to reset. During the resetting process of the extrusion plate 62, the one-way valve on the No. 1 air duct 63 is in a closed state, and the one-way valve on the No. 2 air duct 7 and the air inlet 71 is in an open state. The air inlet 71 intakes air into the interior of the extrusion box 6, and the extrusion plate 62 squeezes the gas entering the air inlet 71 and discharges it into the No. 2 air duct 7, and the No. 2 air duct 7 then sends the gas to the No. 1 air duct 63 and the exhaust pipe, and finally the gas is discharged from the guide box 64, which plays a role in continuously cooling the chip with air during the reciprocating process of the extrusion plate 62. It should be noted that the open state of the one-way valve indicates that exhaust or air intake can be achieved, and conversely, the closed state indicates that exhaust or air intake cannot be achieved.

[0045] like Figures 1 to 3 As shown, the support seat 15 and the second fixing frame 5 are relatively fixedly connected with an assembly frame 8; a pressure roller 81 is rotatably connected between the two assembly frames 8; when the electrochemical microfluidic chip that has just been filmed is transported, the two assembly frames 8 are used to support a pressure roller 81 located above the electrochemical microfluidic chip to be transported, and when the electrochemical microfluidic chip is transported to the bottom of the pressure roller 81, the pressure roller 81 can compact the surface of the transported electrochemical microfluidic chip, so that the electrochemical microfluidic chip and the packaging film are more closely attached, reducing the occurrence of bubbling on the surface of the electrochemical microfluidic chip.

[0046] like Figure 8-Figure 11 As shown, a method for preparing an electrochemical microfluidic chip is used for processing by the electrochemical microfluidic chip preparation system described above. The steps of the method are as follows:

[0047] S1: First, the substrates of multiple electrochemical microfluidic chips are sequentially placed on the No. 1 conveyor 1 for conveyance. When the substrates of the electrochemical microfluidic chips pass through the interior of the No. 1 photolithography machine 11, the No. 1 photolithography machine 11 uses photolithography technology to manufacture microfluidic channels on the substrates of the electrochemical microfluidic chips. Then, the No. 2 photolithography machine 12 uses micro-electromechanical system MEMS technology to integrate electrochemical electrodes in the microfluidic channels.

[0048] S2: The electrochemical microfluidic chip is then sent to the preparation box 13, and the surface of the magnetic beads is modified with anti-Salmonella typhimurium and anti-Escherichia coli antibodies;

[0049] S3: After the detection, the electrochemical microfluidic chip is then sent to the No. 1 fixing rack 14, and a plurality of pressing plates 16 with packaging films are respectively pressed on a plurality of finished electrochemical microfluidic chips. The top surface of the electrochemical microfluidic chip is firstly pasted with film. As the electrochemical microfluidic chip is continuously transported, the film-pasted electrochemical microfluidic chip is turned over to the other side and then pasted with film again, thereby completing the preparation of the electrochemical microfluidic chip.

[0050] The microfluidic channel material described in S1 is polydimethylsiloxane; the electrochemical electrode integrated on the microfluidic channel is used to detect electrochemical signals, and the electrochemical electrode is made of one of gold, platinum and carbon materials; the electrochemical microfluidic chip is provided with sodium alginate gel microspheres, and the surface is modified with antibodies that specifically bind to target bacteria; the pressing plate 16 with a packaging film first presses one side of the electrochemical microfluidic chip, and after the arc plate 52 guides and flips the electrochemical microfluidic chip, the other pressing plate 16 with a packaging film presses the other side of the electrochemical microfluidic chip to complete the packaging;

[0051] Sodium alginate gel microspheres are loaded with different metal ions or other electrochemically active molecules, the particle size range of the sodium alginate gel microspheres is 10-200 microns, the metal ions loaded on the sodium alginate gel microspheres are lead ions, copper ions, zinc ions or cadmium ions, and other electrochemically active molecules loaded on the sodium alginate gel microspheres are thionine, Prussian blue, Nile blue, methyl blue or ferrocene, etc. The sodium alginate gel microspheres are prepared by a sol-gel method, and the particle size range of the magnetic beads is 0.1-10 microns;

[0052] When detecting a variety of bacteria, the electrochemical microfluidic chip achieves efficient, rapid and sensitive detection of a variety of foodborne pathogens such as Salmonella typhimurium and Escherichia coli by combining microfluidic chips and electrochemical biosensor technology;

[0053] The electrochemical microfluidic chip for detecting multiple bacteria adopts the sandwich immunosandwich method, which captures the target bacteria through antibodies modified with magnetic beads, and then combines the captured target bacteria with sodium alginate gel microspheres loaded with different metal ions or other electrochemically active molecules and modified with specific antibodies. The signals obtained by different electrochemical potentials can realize the simultaneous detection of multiple target bacteria at one time.

[0054] When preparing the electrochemical microfluidic chip, the microfluidic channel is made on the polydimethylsiloxane (PDMS) substrate by photolithography technology, and the electrochemical electrode is integrated in the channel. The structure and size of the microfluidic channel are reasonably designed to ensure the flow stability and sufficient reaction of the sample in the channel. Then, the magnetic beads are modified with antibodies, and the specific antibodies are fixed on the surface of the magnetic beads by the EDC / NHS coupling method. First, the magnetic beads are suspended in MES buffer, EDC and NHS are added to activate the surface of the magnetic beads, and then the antibody solution is added and reacted at room temperature to achieve the binding of the antibody to the magnetic beads. Finally, the magnetic beads are washed with PBS buffer to remove the unbound antibodies. Then, the sodium alginate gel microspheres are modified with electrochemically active molecules and specific antibodies. The sodium alginate gel microspheres are prepared by the sol-gel method, and different metal ions or electrochemically active molecules, as well as specific antibodies, are fixed by cross-linking reactions. The specific steps are as follows: The method comprises the following steps: firstly mixing a sodium alginate solution with different metal ions or electrochemically active molecules, and dropping the mixture into a CaCl2 solution to form gel microspheres and fix the electrochemically active components; then suspending the microspheres in a solution containing different antibodies to react and modify the antibodies; finally washing the gel microsphere probes with a PBS buffer solution; and then capturing and detecting bacteria. The sample to be tested is injected into a microfluidic channel, and the sample flow is driven by a micropump. Antibody-modified magnetic beads are introduced into the microfluidic channel to specifically bind to target bacteria in the sample to form an antibody-bacteria complex; then, sodium alginate gel microspheres loaded with different metal ions or electrochemically active molecules and modified with specific antibodies are introduced into the channel to further bind to the antibody-bacteria complex to form a sandwich structure; electrochemical signals are detected at different potentials by electrochemical electrodes, and simultaneous detection of multiple target bacteria is achieved based on the characteristic peaks of the electrical signals.

[0055] When preparing the electrochemical microfluidic chip, a first photolithography machine 11 uses photolithography technology to make a microfluidic channel on a polydimethylsiloxane (PDMS) substrate, and the channel width is 100 microns and the height is 50 microns. The second photolithography machine 12 uses micro-electromechanical system MEMS technology to integrate electrochemical electrodes in the microfluidic channel. The electrochemical microfluidic chip is then sent to a preparation box 13, and the specific antibodies against Salmonella typhimurium and Escherichia coli are fixed on the surface of the magnetic beads by the EDC / NHS coupling method. The magnetic beads are then suspended in MES buffer, EDC and NHS are added, and the reaction is carried out at room temperature to activate the surface of the magnetic beads. The antibody solution is added and the reaction is carried out at room temperature. The magnetic beads are washed with PBS buffer to remove After removing the unbound antibodies, the antibody-modified magnetic beads are obtained, and then the sodium alginate gel microspheres are modified with antibodies: the sodium alginate gel microspheres are prepared by the sol-gel method, and different metal ions (such as lead ions, copper ions, zinc ions or cadmium ions, etc.) or electrochemically active molecules (such as thionine, Prussian blue, Nile blue, methyl blue or ferrocene, etc.), as well as specific antibodies are fixed by cross-linking reactions; the specific steps are as follows: first, the sodium alginate solution is mixed with different metal ions or electrochemically active molecules, and then added dropwise to the CaCl2 solution to form gel microspheres and fix the electrochemically active components, and then the microspheres are suspended in a solution containing different antibodies to react and modify the antibodies, and finally the gel microsphere probes are washed with PBS buffer.

[0056] When detecting multiple bacteria simultaneously, the sample is processed first, and the sample to be tested (such as food samples, medical samples or environmental samples) is injected into the microfluidic channel. The sample flow is driven by a micropump, and then the target bacteria are captured. Antibody-modified magnetic beads are introduced into the microfluidic channel, and specifically bind to the target bacteria in the sample to form an antibody-bacteria complex. Finally, the target bacteria are detected, and sodium alginate gel microspheres loaded with different metal ions or electrochemically active molecules and modified with specific antibodies are introduced into the microfluidic channel, and further bind to the antibody-bacteria complex to form a sandwich structure. The electrochemical signals are detected at different potentials by electrochemical electrodes, and the simultaneous detection of multiple target bacteria is achieved based on the characteristic peak values ​​of the electrical signals.

[0057] In the practical application of the electrochemical microfluidic chip, when performing food safety testing, the electrochemical microfluidic chip of the present invention is applied to the detection of food samples, such as the detection of foodborne pathogens in meat, dairy products and vegetables. The detection sensitivity and specificity of the present invention are verified by testing different food samples.

[0058] When diagnosing medical conditions, electrochemical microfluidic chips are used to detect medical samples, such as pathogen detection in urine, blood, and saliva. The detection effect and clinical application prospects of electrochemical microfluidic chips are verified by testing different medical samples.

[0059] When performing environmental monitoring for medical treatment, the electrochemical microfluidic chip is applied to the detection of environmental samples, such as microbial contamination detection in water, soil and air. The application value of the present invention in environmental monitoring is verified by detecting different environmental samples.

[0060] Through the above specific implementation methods, the electrochemical microfluidic chip of the present invention can efficiently, quickly and sensitively detect multiple bacteria at the same time, significantly improving the detection efficiency and accuracy, and has broad application prospects and market value.

[0061] Working process: When packaging a large number of electrochemical microfluidic chips, first place a large number of electrochemical microfluidic chip substrates on the No. 1 conveyor 1 for transportation, and then send them to the No. 1 photolithography machine 11, the No. 2 photolithography machine 12, the preparation box 13 and the packaging module for processing. The No. 1 photolithography machine 11 can use photolithography technology to manufacture microfluidic channels on the polydimethylsiloxane (PDMS) substrate of the electrochemical microfluidic chip, and the No. 2 photolithography machine 12 uses micro-electromechanical system MEMS technology to integrate electrochemical electrodes in the microfluidic channel. By reasonably designing the structure and size of the microfluidic channel, the sample can ensure stable flow and sufficient reaction in the channel. The preparation box 13 uses EDC / NHS coupling method to fix specific antibodies on the surface of magnetic beads. When the magnetic beads are modified with antibodies, the magnetic beads are first suspended in MES buffer, EDC and NHS are added to activate the surface of the magnetic beads, and then the antibody solution is added to react at room temperature to achieve the binding of the antibody to the magnetic beads. Finally, the magnetic beads are washed with PBS buffer to remove unbound antibodies. Then, the sodium alginate gel microspheres are modified with electrochemically active molecules and specific antibodies. The sodium alginate gel microspheres are prepared by the sol-gel method, and different metal ions or electrochemically active molecules and specific antibodies are fixed by cross-linking reactions. The specific steps are as follows: first, the sodium alginate solution is mixed with different metal ions or electrochemically active molecules, and then the mixture is added dropwise to a CaCl2 solution to form gel microspheres and fix the electrochemically active components. Then, the microspheres are suspended in a solution containing different antibodies. The antibody is modified by the reaction in the middle, and the gel microsphere probe is finally washed with PBS buffer. Then, the bacteria are captured and detected. The sample to be tested is injected into the microfluidic channel, and the sample flow is driven by a micropump. The magnetic beads modified with antibodies are introduced into the microfluidic channel, and specifically bind to the target bacteria in the sample to form an antibody-bacteria complex. Subsequently, sodium alginate gel microspheres loaded with different metal ions or electrochemically active molecules and modified with specific antibodies are introduced into the channel, and further bind to the antibody-bacteria complex to form a sandwich structure. The electrochemical signal is detected at different potentials by electrochemical electrodes. According to the characteristic peak value of the electrical signal, multiple target bacteria can be detected simultaneously. Finally, the finished product is electrochemically processed in large quantities through the packaging module and the No. 1 conveyor. The electrochemical microfluidic chip is packaged quickly without stopping. After the electrochemical microfluidic chip processing is completed, the No. 1 conveyor 1 conveys the finished electrochemical microfluidic chip to the position below the support frame 21 supported by the No. 1 fixing seat 2, and then the output end of the electric cylinder 23 drives the multiple pressing plates 16 with packaging films at the bottom of the connecting frame 24 to extend downward until the multiple pressing plates 16 press the packaging films on the multiple electrochemical microfluidic chip products. The electric slider 22 drives the pressing plates 16 pressed on the multiple electrochemical microfluidic chips to slide synchronously with the conveying speed of the No. 1 conveyor 1. The conveying speed of the No. 1 conveyor 1 is relatively slow, and the conveying and packaging are carried out at the same time. The conveying speed is slowed down to match the packaging speed, thereby improving the packaging effect of the electrochemical microfluidic chip.The packaging film can be kept under pressure on the electrochemical microfluidic chip for a distance, and then the output end of the electric cylinder 23 drives the multiple pressing plates 16 to be lifted, and the electric slider 22 drives the multiple pressing plates 16 to be reset. During the resetting process of the multiple pressing plates 16, the film is moved to the bottom of the pressing plates 16 by a manipulator. Two groups of manipulators are provided, and the two groups of manipulators are respectively installed on the sides of the two support frames 21. The manipulator is mainly used to pick up a new packaging film and stick it to the bottom of the pressing plate 16 after the pressing plate 16 presses the electrochemical microfluidic chip. The vacuum pump installed on the connecting frame 24 cooperates with the multiple pressing plates 16 to adsorb the packaging film respectively, and the electrochemical microfluidic chip is continuously packaged reciprocally, thereby improving the efficiency of packaging the electrochemical microfluidic chip; when packaging the electrochemical microfluidic chip, since the No. 1 conveyor 1 is prone to shaking during transportation, the position of the electrochemical microfluidic chip is offset. In the present invention, two relative guide plates 31 are placed at the end of the No. 1 conveyor 1. The two guide plates 31 can guide the conveying direction of the electrochemical microfluidic chip, so that the electrochemical microfluidic chip can be guided and conveyed to the bottom of the multiple pressure plates 16 for packaging, which plays a role in preventing the electrochemical microfluidic chip from being deflected during conveying. At the same time, the sliding plate 3 on the guide plate 31 is slid on the inner wall of the No. 1 fixed frame 14, so that the distance between the two guide plates 31 can be adaptively adjusted, which is suitable for the preparation of electrochemical microfluidic chips of different models. When the two guide plates 31 are located on the No. 1 conveyor 1 to guide the conveying of the electrochemical microfluidic chip, the fixed plate 4 is fixed to the outer wall of the No. 1 fixed frame 14, and the limiting rod 41 penetrates the fixed plate 4 and is inserted into the limiting hole of the sliding plate 3, so as to limit the position of the guide plate 31 and ensure the stability of the two guide plates 31 in guiding the electrochemical microfluidic chip.

[0062] After the top surface of the electrochemical microfluidic chip is packaged, the bottom surface of the electrochemical microfluidic chip needs to be packaged again. The No. 2 fixing frame 5 cooperates with the support seat 15 to support the No. 2 conveyor 51. The No. 1 conveyor 1 transports the electrochemical microfluidic chip with the top surface packaged to the arc plate 52. The arc plate 52 with a sliding groove is used to receive the electrochemical microfluidic chip. The arc of the arc plate 52 is 75-80 degrees, and the electrochemical microfluidic chip slides down to the No. 2 conveyor 51 along the arc sliding groove. The conveying directions of the No. 1 conveyor 1 and the No. 2 conveyor 51 are consistent, so that the electrochemical microfluidic chip can be quickly turned over and transported. The support seat 15 is also equipped with two relative guide plates 31. With the guidance of the two guide plates 31, the electrochemical microfluidic chip is transported to the second group of packaging modules for further packaging, which plays a role in double-sided packaging of the electrochemical microfluidic chip.

[0063] When encapsulating the electrochemical microfluidic chip, it is necessary to press the hot encapsulation film onto the electrochemical microfluidic chip, but the heat is conducted to the electrochemical microfluidic chip for a long time, which is easy to cause damage to the electrochemical microfluidic chip. The extrusion box 6 is fixed to the tail of the support frame 21, and the electric slider 22 can squeeze the extrusion rod 61 during the sliding process. The extrusion rod 61 drives the extrusion plate 62 to squeeze the gas inside the extrusion box 6, and the elastic member 65 is squeezed and contracted. The squeezed gas is then sent to the guide box 64 through the No. 1 air duct 63 and the exhaust pipe for discharge. The guide box 64 is facing the electrochemical microfluidic chip being transported on the No. 1 conveyor 1, and the squeezed gas is used to air-cool the electrochemical microfluidic chip that has just been separated from the pressing plate 16, so as to reduce the heat of the encapsulation film and the damage to the electrochemical microfluidic chip. When the electrochemical microfluidic chip that has just been filmed is air-cooled, the electric slider 22 slides and squeezes the extrusion rod 61, and the extrusion plate 62 squeezes the elastic member 65 and contracts. At this time, the No. 2 air duct The one-way valves on the No. 1 air duct 63 and the air inlet 71 are in a closed state, and the one-way valve on the No. 1 air duct 63 is in an open state. The extrusion plate 62 can squeeze the gas inside the extrusion box 6 through the No. 1 air duct 63 to be discharged to the guide box 64, and the electrochemical microfluidic chip just pasted with the film is cooled by air. Then the electric slider 22 is reset, and the elastic force of the elastic member 65 drives the extrusion plate 62 to reset. During the resetting process of the extrusion plate 62, the one-way valve on the No. 1 air duct 63 is in a closed state, and the No. 2 air duct 7 and the air inlet 71 are in a closed state. The one-way valve on 1 is in the open state, and the air inlet 71 enters the interior of the extrusion box 6. The extrusion plate 62 squeezes the gas entering the air inlet 71 and discharges it into the No. 2 air duct 7. The No. 2 air duct 7 then sends the gas to the No. 1 air duct 63 and the exhaust pipe, and finally the gas is discharged at the guide box 64, which plays a role in continuously cooling the chip with air during the reciprocating process of the extrusion plate 62. It should be noted that the open state of the one-way valve indicates that exhaust or intake is possible, and conversely, the closed state indicates that exhaust or intake is not possible;

[0064] When the electrochemical microfluidic chip that has just been film-affixed is transported, two assembly frames 8 are used to support a pressure roller 81 located above the electrochemical microfluidic chip to be transported. When the electrochemical microfluidic chip is transported below the pressure roller 81, the pressure roller 81 can compact the surface of the transported electrochemical microfluidic chip, so that the electrochemical microfluidic chip and the packaging film are more closely attached, thereby reducing the occurrence of bubbling on the surface of the electrochemical microfluidic chip.

[0065] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A system for preparing an electrochemical microfluidic chip, comprising a No. 1 conveyor (1), wherein the No. 1 conveyor (1) is used for continuously conveying chip preparation on an electrochemical microfluidic chip automated production line; the No. 1 conveyor (1) is sequentially arranged with a No. 1 photolithography machine (11), a No. 2 photolithography machine (12), a preparation box (13) and a packaging module, wherein the preparation box (13) is located on a side of the No. 2 photolithography machine (12) away from the No. 1 photolithography machine (11), and the packaging module is used for packaging finished electrochemical microfluidic chips.

2. The system for preparing an electrochemical microfluidic chip according to claim 1, characterized in that: A No. 1 fixed frame (14) is fixedly connected to one side of the No. 1 conveyor (1) close to the preparation box (13); a support seat (15) is fixedly connected to one side of the No. 1 fixed frame (14) away from the preparation box (13), and the support seat (15) is installed at the tail end of the No. 1 conveyor (1); the top of the No. 1 fixed frame (14) is fixedly connected to the No. 1 fixed seat (2); the packaging module comprises a pressure plate (16), a support frame (21), an electric slider (22), an electric cylinder (23) and a connecting frame (24); the support frame (21) is fixedly connected to the top of the No. 1 fixed seat (2); the electric slider (22) is slidably connected to the bottom end of the support frame (21); the electric cylinder (23) is fixedly connected to the middle bottom end of the electric slider (22); the connecting frame (24) is fixedly connected to the output end of the electric cylinder (23); a plurality of pressure plates (16) are arranged horizontally and fixedly connected to the bottom end of the connecting frame (24).

3. The system for preparing an electrochemical microfluidic chip according to claim 2, characterized in that: Two sliding plates (3) are relatively slidably connected to the first fixing frame (14); guide plates (31) are fixedly connected to the outer walls of the two sliding plates (3), and the guide plates (31) are slidably connected to the inner wall of the first fixing frame (14).

4. The system for preparing an electrochemical microfluidic chip according to claim 3, characterized in that: A plurality of limiting holes are provided on the two sliding plates (3); two fixing plates (4) are relatively fixedly connected to the first fixing frame (14), and the fixing plates (4) are located above the sliding plates (3); a limiting rod (41) is inserted through the fixing plate (4), and the limiting rod (41) is inserted into the limiting hole.

5. The system for preparing an electrochemical microfluidic chip according to claim 3, characterized in that: A No. 2 fixing frame (5) is fixedly connected to the side of the support seat (15) away from the No. 1 fixing frame (14); a No. 2 conveyor (51) is installed between the No. 2 fixing frame (5) and the support seat (15); an arc plate (52) is fixedly connected to the outer wall of the support seat (15), and the arc plate (52) is located at the end of the No. 1 conveyor (1) and above the No. 2 conveyor (51), and a sliding groove is opened inside the arc plate (52); a No. 2 fixing seat (53) is fixedly connected to the support seat (15), and a second group of packaging modules is installed on the No. 2 fixing seat (53).

6. The system for preparing an electrochemical microfluidic chip according to claim 2, characterized in that: The outer wall of the support frame (21) is fixedly connected to an extrusion box (6); the inner wall of the extrusion box (6) is slidably connected to an extrusion rod (61); one end of the extrusion rod (61) located inside the extrusion box (6) is fixedly connected to an extrusion plate (62), and the extrusion plate (62) is slidably connected to the inside of the extrusion box (6); the inside of the extrusion box (6) is fixedly connected to a No. 1 air duct (63); the outer wall of the extrusion box (6) is fixedly connected to a guide box (64) near the No. 1 air duct (63) through an exhaust pipe; an elastic member (65) is fixedly connected between the inner wall of the extrusion box (6) and the outer wall of the extrusion plate (62).

7. The system for preparing an electrochemical microfluidic chip according to claim 6, characterized in that: The extrusion box (6) is fixedly connected to a No. 2 air duct (7); an air inlet (71) is provided inside the extrusion box (6) near the extrusion rod (61); and one-way valves are fixedly connected to the No. 1 air duct (63), the No. 2 air duct (7) and the air inlet (71).

8. The system for preparing an electrochemical microfluidic chip according to claim 5, characterized in that: The support seat (15) and the second fixing frame (5) are both relatively fixedly connected with an assembly frame (8); and a pressure roller (81) is rotatably connected between the two assembly frames (8).

9. A method for preparing an electrochemical microfluidic chip, the method being applicable to the electrochemical microfluidic chip preparation system according to any one of claims 1 to 8, characterized in that: The steps of this method are as follows: S1: First, the substrates of a plurality of electrochemical microfluidic chips are sequentially placed on a No. 1 conveyor (1) for conveyance. When the substrates of the electrochemical microfluidic chips pass through a No. 1 photolithography machine (11), the No. 1 photolithography machine (11) uses photolithography technology to manufacture microfluidic channels on the substrates of the electrochemical microfluidic chips. Then, the No. 2 photolithography machine (12) uses micro-electromechanical system (MEMS) technology to integrate electrochemical electrodes in the microfluidic channels. S2: The electrochemical microfluidic chip is then sent to a preparation box (13) to modify the surface of the magnetic beads with anti-Salmonella typhimurium and anti-Escherichia coli antibodies; S3: After the electrochemical microfluidic chip is tested, it is sent to the first fixing rack (14), and a plurality of pressing plates (16) with packaging films are respectively pressed on a plurality of finished electrochemical microfluidic chips. The top surface of the electrochemical microfluidic chip is firstly laminated. As the electrochemical microfluidic chip is continuously transported, the laminated electrochemical microfluidic chip is turned over to the other side and laminated again, thereby completing the preparation of the electrochemical microfluidic chip.

10. The method for preparing an electrochemical microfluidic chip according to claim 9, characterized in that: The microfluidic channel material described in S1 is polydimethylsiloxane; the electrochemical electrode integrated on the microfluidic channel is used to detect electrochemical signals, and the electrochemical working electrode is made of one of gold, platinum and carbon materials; the electrochemical microfluidic chip is provided with sodium alginate gel microspheres, and the surface is modified with antibodies that specifically bind to target bacteria; a pressing plate (16) with a packaging film first presses one side of the electrochemical microfluidic chip, and after the arc plate (52) guides and flips the electrochemical microfluidic chip, another pressing plate (16) with a packaging film presses the other side of the electrochemical microfluidic chip to complete the packaging.

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