CN114113010A - Automatic bacteria detection system and method based on digital micro-fluidic - Google Patents
Automatic bacteria detection system and method based on digital micro-fluidic Download PDFInfo
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- 241000894006 Bacteria Species 0.000 title claims abstract description 49
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- 238000005415 bioluminescence Methods 0.000 claims abstract description 13
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- IGXWBGJHJZYPQS-SSDOTTSWSA-N D-Luciferin Chemical compound OC(=O)[C@H]1CSC(C=2SC3=CC=C(O)C=C3N=2)=N1 IGXWBGJHJZYPQS-SSDOTTSWSA-N 0.000 claims description 5
- CYCGRDQQIOGCKX-UHFFFAOYSA-N Dehydro-luciferin Natural products OC(=O)C1=CSC(C=2SC3=CC(O)=CC=C3N=2)=N1 CYCGRDQQIOGCKX-UHFFFAOYSA-N 0.000 claims description 5
- BJGNCJDXODQBOB-UHFFFAOYSA-N Fivefly Luciferin Natural products OC(=O)C1CSC(C=2SC3=CC(O)=CC=C3N=2)=N1 BJGNCJDXODQBOB-UHFFFAOYSA-N 0.000 claims description 5
- 108060001084 Luciferase Proteins 0.000 claims description 5
- 239000005089 Luciferase Substances 0.000 claims description 5
- DDWFXDSYGUXRAY-UHFFFAOYSA-N Luciferin Natural products CCc1c(C)c(CC2NC(=O)C(=C2C=C)C)[nH]c1Cc3[nH]c4C(=C5/NC(CC(=O)O)C(C)C5CC(=O)O)CC(=O)c4c3C DDWFXDSYGUXRAY-UHFFFAOYSA-N 0.000 claims description 5
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- ZKHQWZAMYRWXGA-UHFFFAOYSA-N Adenosine triphosphate Natural products C1=NC=2C(N)=NC=NC=2N1C1OC(COP(O)(=O)OP(O)(=O)OP(O)(O)=O)C(O)C1O ZKHQWZAMYRWXGA-UHFFFAOYSA-N 0.000 description 14
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- JLVVSXFLKOJNIY-UHFFFAOYSA-N Magnesium ion Chemical compound [Mg+2] JLVVSXFLKOJNIY-UHFFFAOYSA-N 0.000 description 1
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- G01—MEASURING; TESTING
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- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
- G01N21/64—Fluorescence; Phosphorescence
- G01N21/6428—Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes"
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Abstract
The invention provides an automatic bacteria detection system and method based on digital microfluidics, wherein the system comprises: the digital microfluidic chip is used for separating and enriching bacteria in a sample; the optical path acquisition module is arranged right above the digital microfluidic chip and used for acquiring optical signals; the magnetic field control module is used for controlling the activation and the closing of a magnetic field during magnetic immune bioluminescence; the signal conditioning module is used for conditioning the optical signal collected by the optical path collecting module; and the chip control circuit is respectively connected with the digital microfluidic chip and the light path acquisition module. The method utilizes the digital microfluidic technology to rapidly carry out automatic detection on bacteria, completes generation, division and transportation of liquid drops on the basis of controlling to realize the movement of single or a plurality of discrete liquid drops on a chip plane, and has the advantages of miniaturization, integration, automation, parallelization, high efficiency and low cost.
Description
Technical Field
The invention relates to the technical field of digital micro-fluidic, in particular to an automatic bacteria detection system and method based on digital micro-fluidic.
Background
The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.
Pathogens, chemical contamination and illegal food additives are three major sources of food safety problems, with pathogen contamination by pathogenic bacteria being the primary problem. The most effective means for reducing the threat of pathogens is to timely and accurately detect pathogens in food. The detection method specified by the national standard is a traditional culture method, the detection result of the method is accurate, the cost is relatively low, but the detection time is 24-48 hours, the time is long, the labor is wasted, and obviously the requirements of the current food industry on quick and automatic detection cannot be met. In order to reduce the detection time, there are mainstream methods such as a metabolic detection method, a molecular biological detection method, a biosensor detection method, an immunological detection method, and the like for detecting bacteria, but in practical applications, these methods all face a problem that automated detection cannot be performed.
The micro-fluidic chip utilizes micro-channels with different structures and external force fields with various forms to manipulate, process and control trace fluids or samples on a micro scale, thereby realizing the integration of partial or even all functions of a traditional laboratory on a microchip, and the schematic diagram of the micro-fluidic chip is shown in figure 1. Compared with the traditional method, the method has the advantages of low cost, less reagent consumption, capability of automatic operation and the like, and represents the development direction of miniaturization of future biological detection. However, the limitations of the conventional microfluidic chip are also very obvious, which requires the cooperation of mechanical pumps and valves, has high integration difficulty, is difficult to realize the continuous multi-step processing of samples, and has a quick effect on the precise control of the positions and reaction times of multiple reagents.
In recent years, with the wide application of digital microfluidic technology, the digital microfluidic technology is proposed to rapidly carry out automatic detection on bacteria. Digital Microfluidics (DMF) is a new technology for manipulating micro-volume liquids developed on chips in recent years. The principle is that voltage is applied to a polar plate electrode of a chip, so that the solid-liquid surface tension of a chip dielectric layer and liquid drops on the chip dielectric layer is changed, and the operation of generating, splitting, transporting and the like of the liquid drops is completed on the basis of controlling and realizing the movement of single or a plurality of discrete liquid drops on a chip plane. The digital microfluidic chip has the advantages of miniaturization, integration, automation, parallelization, high efficiency, low cost and the like, and is widely applied to the fields of biochemical experiment analysis, high-tech medical treatment, optical research and the like.
However, no digital microfluidic technology for automatically detecting bacteria in a sample has been studied, so there is a need for an automated bacteria detection system and method based on digital microfluidic technology.
Disclosure of Invention
The invention provides an automatic bacteria detection system and method based on digital microfluidics in order to solve the problems.
According to some embodiments, the invention adopts the following technical scheme:
an automated bacteria detection system based on digital microfluidics, comprising:
the digital microfluidic chip and the chip control circuit are used for controlling the driving of the electrodes through the chip control circuit and are used for separating and enriching samples;
the optical path acquisition module is arranged right above the digital microfluidic chip and used for acquiring optical signals;
the magnetic field control module is used for controlling the activation and the closing of a magnetic field during magnetic immune bioluminescence;
the signal conditioning module is used for conditioning the optical signal collected by the optical path collecting module;
the chip control circuit is respectively connected with the digital micro-fluidic chip and the light path acquisition module.
Further, in the digital microfluidic chip, a hydrophobic layer is uniformly coated on the surface of the dielectric layer by a spin coating method.
Furthermore, the optical path acquisition module comprises a photomultiplier tube PMT and a gain control circuit.
Furthermore, the photomultiplier converts the obtained different light intensity signals into electric signals with different voltages and outputs the electric signals to an upper computer so as to reflect the intensity of the current magnetic immune bioluminescence.
Further, the signal conditioning module comprises a signal amplifier, a fourth-order low-pass filter and a wave trap.
Further, the conditioning of the optical signal collected by the optical path collection module is specifically to condition the electrical signal output by the optical path collection module, and eliminate the noise of the signal collected by the photomultiplier through filtering amplification and analog-to-digital conversion.
Further, the chip control circuit is used for respectively outputting a digital microfluidic chip control program and a control program of a power supply and a gain of a photomultiplier in the optical path acquisition module.
An automated bacteria detection method based on digital microfluidics, comprising:
the driving of the electrode is controlled by a chip control circuit, liquid drops containing magnetic beads for capturing bacteria move to a magnetic bead separation point, a magnetic field is started by a magnetic field control module to enrich the magnetic beads, and the liquid drops are moved to a waste liquid area;
further, the driving of the electrodes is controlled by a chip control circuit, and bacteria not captured by the antibody are washed away.
Further, the driving of the electrode is controlled by a chip control circuit, the bacteria are cracked, ATP in the bacteria is released, the ATP is fully reacted with luciferin and luciferase in the fluorescent reagent, fluorescence is generated, and the fluorescence is detected.
Compared with the prior art, the invention has the beneficial effects that:
the invention utilizes the digital micro-fluidic technology to rapidly and automatically detect bacteria, completes the generation, the division and the transportation of liquid drops on the basis of controlling the movement of single or a plurality of discrete liquid drops on a chip plane, and has the advantages of miniaturization, integration, automation, parallelization, high efficiency and low cost.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the application and, together with the description, serve to explain the application and are not intended to limit the application.
FIG. 1 is a system configuration diagram of the present embodiment;
FIG. 2 is a schematic view of the droplet driving principle of the present embodiment;
FIG. 3 is a circuit diagram of the power supply control circuit of the photomultiplier tube PMT of the present embodiment;
FIG. 4 is a circuit for controlling the gain of the photomultiplier tube PMT according to this embodiment;
FIG. 5 is a circuit diagram of the signal conditioning module of the present embodiment;
FIG. 6 is a diagram showing the electrowetting effect of the present embodiment;
FIG. 7 is a circuit diagram of a chip control circuit of the present embodiment;
FIG. 8 is a graph of bioluminescence response data for different concentrations of ATP sample of this example;
FIG. 9 is a schematic structural diagram of the digital microfluidic chip of the present embodiment;
wherein, 1, a liquid storage area; 2. a waste liquid zone; 3. a magnetic bead separation point; 4. a mixing zone; 5. and (6) detecting the area.
The specific implementation mode is as follows:
the invention is further described with reference to the following figures and examples.
It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.
Adenosine Triphosphate (ATP) is an energy substance present in all biological cells and is a common energy carrier for all vital activities. Cells with metabolic activity contain a certain amount of ATP, the ATP is combined with luciferin and luciferase to generate fluorescence under the environment of magnesium ions and oxygen, and the number of bacteria can be detected by detecting the luminous intensity of ATP. In recent years, magnetic immune separation technology has become a research hotspot in the field of bacteria detection due to its extremely high enrichment efficiency. The magnetic immune bioluminescence combines an ATP luminescence principle with a magnetic immune separation technology and is used for converting separated and enriched target bacteria into a bioluminescence signal.
In a first aspect, the present invention provides an automated bacteria detection system based on digital microfluidics, comprising:
the digital microfluidic chip and the chip control circuit are used for controlling the driving of the electrodes through the chip control circuit and are used for separating and enriching bacteria in the sample;
the optical path acquisition module is arranged right above the digital microfluidic chip and used for acquiring optical signals;
the magnetic field control module is used for controlling the activation and the closing of a magnetic field during magnetic immune bioluminescence;
the signal conditioning module is used for conditioning the optical signal collected by the optical path collecting module;
the chip control circuit is respectively connected with the digital micro-fluidic chip and the light path acquisition module.
In particular, the method comprises the following steps of,
as shown in fig. 2, the digital microfluidic driving and detecting system includes five parts, namely a digital microfluidic chip, a light path collecting module for collecting light signals, a magnetic field control module for magnetic immune bioluminescence, a signal conditioning module for conditioning signals collected by the light path collecting module, and a chip control circuit respectively connected to the digital microfluidic chip and the light path collecting module.
The digital microfluidic chip comprises a substrate, an electrode layer, a dielectric layer and a hydrophobic layer. The substrate and the electrode layer are made of a Printed Circuit Board (PCB). The dielectric layer is uniformly coated on the upper surface of the electrode layer, and the hydrophobic layer is uniformly coated on the surface of the dielectric layer by a spin coating method. The dielectric layer material adopts an Ethylene Tetrafluoroethylene (ETFE) film with the thickness of 12 microns, and the hydrophobic layer material adopts a fluoroplastic material of Cytonix company. In addition, a layer of silicone oil is coated on the hydrophobic layer, so that the moving effect of the liquid drops is enhanced.
An interdigital pattern is adopted by the electrode on the electrode layer, so that the moving effect of liquid drops is enhanced. As shown in fig. 9, the schematic diagram of the digital microfluidic chip includes an electrode layer including a liquid storage region 1, a waste liquid region 2, a magnetic bead separation point 3, a mixing region 4, and a detection region 5.
The light path acquisition module is positioned right above the digital microfluidic chip and consists of a photomultiplier tube (PMT), a power supply thereof and a gain control circuit. The bioluminescent signals are converged to an effective induction area of the photomultiplier through the objective lens, different light intensity signals obtained in the photomultiplier are converted into electric signals with different voltages to be output, and the output of the photomultiplier is transmitted to an upper computer in real time to reflect the intensity of the current magnetic immune bioluminescence. In addition, in order to enable the photomultiplier and the system to be supplied with power uniformly, and simultaneously, in order to match different gain requirements in the detection process, a photomultiplier power supply and a gain control circuit matched with the photomultiplier power supply and the gain control circuit are designed according to data in a data manual.
The magnetic field control module is used for controlling the activation and the closing of a magnetic field during magnetic immune bioluminescence.
The signal conditioning module comprises a signal amplifier, a fourth-order low-pass filter, a wave trap and the like, and is used for conditioning the electric signal output by the optical path acquisition module and eliminating the noise of the signal acquired by the photomultiplier through filtering amplification and analog-to-digital conversion.
The chip control circuit is respectively connected with the digital microfluidic chip switch circuit and the light path acquisition module and is used for respectively outputting a digital microfluidic chip control program and a control program of a power supply and a gain of a photomultiplier in the light path acquisition module.
As an example of the manner in which the device may be used,
the photomultiplier tube (PMT) power supply control circuit is shown in figure 3, the PMT needs to provide a power supply of plus or minus 12V for supplying power, and the system adopts a power supply of plus or minus 5V for supplying power, so that a power supply module produced by Anshijie company is added at the input end of the power supply, and the plus or minus 5V input voltage is converted into plus or minus 15V. The +15V voltage is input into the three-terminal voltage-stabilizing integrated chip L7812CV, the +15V voltage is converted into +12V voltage, the obtained-15V voltage is input into the three-terminal voltage-stabilizing integrated chip L7912CV, the-15V voltage is converted into-12V voltage, and the generated 12V is output by the voltage-stabilizing diode and then supplies power for the PMT.
The photomultiplier tube (PMT) gain control circuit is shown in FIG. 4, different fluorescent intensities need to be matched with different PMT gains to meet different sensitivities
The gain of the PMT is voltage controlled, and thus it is necessary to output different gains by inputting different voltages. The circuit adopts REF193 as a precise band-gap reference voltage source, so that the +3V reference voltage is generated. The +3V reference voltage is reduced to +1V after the voltage is subjected to capacitance filtering and resistance voltage division, and the maximum control voltage is provided for the PMT. And the control voltage is divided by eight resistors to divide the voltage into eight control voltages with the same interval. The eight-out-of-one single-pole multi-throw switch CD4051 is used to select different gain voltages, and the voltages are isolated and output through an operational amplifier OP07CN (with the characteristics of low noise and high precision).
As an example of the manner in which the device may be used,
the circuit connection diagram of the signal conditioning module is shown in fig. 5, and for the selected photomultiplier, the invention designs AD8630 as a preamplifier; a Butterworth fourth-order low-pass filter with the cut-off frequency of 1KHz is designed to filter signals; an amplifier with adjustable gain is designed by the ADG804, and the detection range of the system is increased.
In a second aspect, the invention provides an automated bacteria detection method based on digital microfluidics, comprising:
the driving of the electrode is controlled by a chip control circuit, liquid drops containing magnetic beads for capturing bacteria move to a magnetic bead separation point, a magnetic field is started by a magnetic field control module to enrich the magnetic beads, and the liquid drops are moved to a waste liquid area;
further, the driving of the electrodes is controlled by a chip control circuit, and bacteria not captured by the antibody are washed away.
Further, the driving of the electrode is controlled by a chip control circuit, the bacteria are cracked, ATP in the bacteria is released, the ATP is fully reacted with luciferin and luciferase in the fluorescent reagent, fluorescence is generated, and the fluorescence is detected.
In particular, the method comprises the following steps of,
the detection method of the automatic bacteria detection system based on the digital microfluidic technology comprises the following specific processes:
step A, respectively placing liquid drops containing magnetic beads for capturing bacteria, a cracking reagent, a fluorescent reagent and a cleaning solution in four liquid storage areas 1, adding a proper amount of silicone oil to wrap the liquid drops, and pre-electrifying the electrodes by using a chip control circuit.
And step B, controlling the driving of the electrodes by using a chip control circuit, moving the liquid drops containing the magnetic beads for capturing bacteria to the magnetic bead separation point 3, starting a magnetic field by using a magnetic field control module to enrich the magnetic beads, and then moving the liquid drops to the waste liquid area 2.
And step C, controlling the driving of the electrode by using a chip control circuit, moving the cleaning solution to the magnetic bead separation point 3, closing the magnetic field by using a magnetic field control module, then moving the liquid drop to the mixing area 4, and returning to the magnetic bead separation point 3 after mixing and oscillation. The magnetic field is then switched on to enrich the magnetic beads and move the droplets to the waste zone 2. This step is intended to wash away bacteria not captured by the magnetic beads.
And D, controlling the driving of the electrode by using a chip control circuit, moving the cracking reagent to the magnetic bead separation point 3, closing the magnetic field by using a magnetic field control module, moving the liquid drop to the mixing area 4, mixing and vibrating, and moving to the detection area 5. This step is intended to lyse the bacteria, releasing their ATP.
And step F, controlling the driving of the electrodes by using a chip control circuit, moving the fluorescent reagent to the detection area 5, and fusing the liquid drops in the step D. And then moving the liquid drops to a mixing area 4, enabling the mixed liquid drops to fully react in a liquid drop driving mode, and returning to a detection area 5 after the mixed liquid drops vibrate. This step is intended to allow sufficient reaction of ATP with luciferin and luciferase in the fluorogenic reagent to produce fluorescence.
Step G detects fluorescence.
As an example of the manner in which the device may be used,
the substrate and the electrodes of the chip in the system are made of a Printed Circuit Board (PCB) and comprise the substrate and the electrodes, and a dielectric layer and a hydrophobic layer are covered on the substrate and the electrodes.
When the electrode is not electrified, the liquid drop and the contact surface are in a hydrophobic state, and the contact angle is large; when the electrode is electrified, the hydrophobic state disappears, the contact angle is reduced, and the contact surface is increased, which is called electrowetting.
The principle of driving droplets is based on the electrowetting phenomenon, as shown in fig. 6, in which the droplets are initially located on electrode No. 1, and at this time, no electrodes are energized; when the adjacent No. 2 electrode is electrified, the contact surface of the liquid drop and the No. 2 electrode is increased and finally moves to the position above the No. 2 electrode completely.
As an example of the manner in which the device may be used,
as shown in fig. 7, the chip control circuit controls the transistor and the relay by controlling the photoelectric coupler through stm32, thereby realizing the power-up of the electrodes on the chip. Because the system adopts a power supply of +/-5V for power supply, the voltage required to be applied for driving the liquid drops is usually dozens to hundreds of volts, and the amplitude is required to be continuously changed according to the requirement, if an external high-voltage circuit is directly connected with a control system, the problem that the chip is burnt due to the backward flow of current can occur. For this purpose, an opto-coupler is used to isolate the control circuit from the external high voltage.
The purpose of the electrode drive is to realize the movement of the liquid drop on the chip, thereby realizing a series of operations of generation, movement, splitting and mixing of the liquid drop (the liquid drop is dispensed from the liquid storage tank, the dispensed liquid drop is transported to a target position, a single liquid drop is separated into two liquid drops, and the two liquid drops can be combined into one liquid drop).
As an example of the manner in which the device may be used,
the fluorescence is detected, in the detection process, a photomultiplier tube (PMT) is used for collecting optical signals on the digital microfluidic chip, different light intensity signals obtained in the PMT are converted into electric signals with different voltages and then are output to an upper computer, and therefore the intensity of the magnetic immune bioluminescence is reflected, and the number of bacteria is further reflected.
FIG. 8 is a graph of bioluminescence response data for different concentrations of ATP sample.
As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Although the embodiments of the present invention have been described with reference to the accompanying drawings, it is not intended to limit the scope of the present invention, and it should be understood by those skilled in the art that various modifications and variations can be made without inventive efforts by those skilled in the art based on the technical solution of the present invention.
Claims (10)
1. An automated bacteria detection system based on digital microfluidics, comprising:
the digital microfluidic chip and the chip control circuit are used for controlling the driving of the electrodes through the chip control circuit and are used for separating and enriching samples;
the optical path acquisition module is arranged right above the digital microfluidic chip and used for acquiring optical signals;
the magnetic field control module is used for controlling the activation and the closing of a magnetic field during magnetic immune bioluminescence;
the signal conditioning module is used for conditioning the optical signal collected by the optical path collecting module;
the chip control circuit is respectively connected with the digital micro-fluidic chip and the light path acquisition module.
2. The automated bacteria detection system based on digital microfluidics according to claim 1, wherein in the digital microfluidic chip, a hydrophobic layer is uniformly coated on the surface of the dielectric layer by a spin coating method.
3. The automated bacteria detection system based on digital microfluidics of claim 2, wherein the optical path acquisition module comprises a photomultiplier tube (PMT) and a gain control circuit.
4. The automated bacteria detection system based on digital microfluidics according to claim 3, wherein the photomultiplier tube converts the obtained different light intensity signals into electrical signals with different voltages and outputs the electrical signals to an upper computer.
5. The automated bacteria detection system based on digital microfluidics of claim 4, wherein the signal conditioning module comprises a signal amplifier, a fourth-order low-pass filter and a wave trap.
6. The automated bacteria detection system based on digital microfluidics according to claim 5, wherein the optical signal collected by the optical path collection module is conditioned, specifically, the electrical signal output by the optical path collection module is conditioned, and noise of the signal collected by the photomultiplier is eliminated through filtering amplification and analog-to-digital conversion.
7. The automated bacteria detection system based on digital microfluidics of claim 6, wherein the chip control circuit is configured to output a control program for the digital microfluidic chip and a control program for power supply and gain of the photomultiplier in the optical path acquisition module, respectively.
8. An automated bacteria detection method based on digital microfluidics, which is based on the automated bacteria detection system based on digital microfluidics as claimed in any one of claims 1 to 7, and which comprises:
the driving of the electrode is controlled by the chip control circuit, liquid drops containing magnetic beads for capturing bacteria move to the magnetic bead separation point, the magnetic field is started by the magnetic field control module, the magnetic beads are enriched, and the liquid drops are moved to the waste liquid area.
9. The automated bacteria detection method based on digital microfluidics according to claim 8, wherein the bacteria that are not captured by the antibody are washed away by controlling the driving of the electrodes by the chip control circuit.
10. The automated bacteria detection method based on digital microfluidics, according to claim 9, wherein the driving of the electrodes is controlled by a chip control circuit, bacteria are lysed, ATP in the bacteria is released, and the ATP is sufficiently reacted with luciferin and luciferase in a fluorescent reagent to generate fluorescence, and the fluorescence is detected.
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