Micro-fluidic chip and droplet state monitoring method

Abstract

The invention relates to a micro-fluidic chip and a droplet state monitoring method, belongs to the technical field of micro-fluidic chips, and solves the problem that driving control and state monitoring cannot be performed on a plurality of channels of the micro-fluidic chip at the same time in the prior art. The micro-fluidic chip comprises a chip substrate, a plurality of voltage division elements and a plurality of voltage division acquisition circuits, a plurality of micro-channels are formed on the chip substrate, each micro-channel is correspondingly provided with an electrode group, and each electrode group comprises a common electrode and a plurality of driving electrodes; the driving power supply is respectively connected with all the driving electrodes; a voltage division element is connected in series between the driving power supply and each common electrode, the voltage division elements are in one-to-one correspondence with the voltage division acquisition circuits, and each voltage division acquisition circuit is used for acquiring voltage division signals at the two ends of one voltage division element. According to the invention, driving control and state monitoring are simultaneously carried out on a plurality of channels of the micro-fluidic chip, and the accuracy of feedback liquid drop state position information is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of microfluidic chips, and in particular to a microfluidic chip and a droplet monitoring method. Background Art

[0002] In the application of biological reaction processes in microfluidic chips, different types of droplets in the chip need to complete multiple movement and reaction functions such as migration, fusion, and splitting. Therefore, the source of power for droplet movement, that is, the drive control of the droplets and the feedback of the movement position information during the drive process, are important links in the realization of the functions of the chip and even the microfluidic equipment. Real-time monitoring and feedback of the droplet movement state can enable the equipment operator to judge the working state of the microfluidic chip, whether the droplets move normally according to the planned movement path, and whether the droplet movement position is correct, so that when abnormal droplet movement occurs in the chip, the cause can be promptly investigated and adjustment measures can be taken.

[0003] At present, most of the real-time monitoring schemes for the motion state of droplets in microfluidic chips use the capacitance value collected by the capacitance detection circuit to determine the position of the droplets. Among them, some hardware circuits use timers to time-share the voltage drive circuit and the capacitance detection circuit. The voltage drive circuit and the capacitance detection circuit cannot work at the same time. When performing capacitance detection, the drive control of the droplet needs to be stopped, which takes up a lot of time and resources. In addition, the existing capacitance detection circuit has problems such as large interference and slow detection speed.

[0004] Since changes in capacitance will cause changes in the corresponding voltage signal, the existing technology also monitors the motion state of the droplet through a voltage acquisition circuit. For example, in the existing droplet drive information feedback sensor circuit, a method (point drawing method) is adopted to read the drive voltage signal value point by point and then superimpose it to form a feedback curve. However, this method has problems such as inaccurate sampling data and abnormal individual data points leading to inaccurate overall feedback information. That is, the data sampling frequency needs to meet certain requirements and abnormal signal points need to be shielded. At the same time, for the voltage signal changes caused by capacitance changes, the existing acquisition method uses the switching of the range to ensure that signals of different sizes can be accurately identified. However, the long range switching time of this method causes the range switching during the droplet movement to fail to keep up with the change of the equivalent capacitance, which will cause delays in the acquisition of voltage signal data and feedback of erroneous information.

[0005] At the same time, existing microfluidic chips generally perform drive control and status monitoring on droplets in a single microchannel separately, and are unable to perform drive control and status monitoring on multiple channels of the microfluidic chip at the same time, resulting in low working efficiency of the microfluidic chip. Summary of the invention

[0006] In view of the above analysis, the embodiments of the present invention aim to provide a microfluidic chip and a droplet state monitoring method to solve the problems in the prior art that multiple channels of the microfluidic chip cannot be driven and controlled and state monitored simultaneously, and the acquired droplet motion position information has low accuracy and poor real-time performance.

[0007] In one aspect, an embodiment of the present invention provides a microfluidic chip, the microfluidic chip comprising: a chip substrate, a plurality of voltage-dividing elements and a plurality of voltage-dividing acquisition circuits,

[0008] A plurality of microchannels for accommodating droplets are formed on the chip substrate, and each of the microchannels is respectively provided with an electrode group for controlling the movement of the droplets, and the electrode group includes a common electrode and a plurality of driving electrodes arranged at intervals along the movement path of the droplets;

[0009] A driving power source is connected to all the driving electrodes respectively, and the driving power source applies a driving voltage to one or more driving electrodes to control the movement of liquid in one or more of the microchannels;

[0010] A voltage divider element is connected in series between the driving power supply and each of the common electrodes. The voltage divider elements correspond to the voltage divider collection circuits one by one. Each of the voltage divider collection circuits is used to collect a voltage divider signal at both ends of the voltage divider element.

[0011] The movement position information of the droplets in each microchannel is obtained according to the voltage division signal collected by each voltage division collection circuit and the driving voltage signal of the driving power supply.

[0012] Based on the further improvement of the above-mentioned microfluidic chip, the driving power supply is connected to all the driving electrodes through a switch array module, and the switch array module is used to select the connection between one or more of the driving electrodes and the driving power supply.

[0013] Based on the further improvement of the above-mentioned microfluidic chip, the chip substrate includes a first substrate and a second substrate arranged relatively to each other, the common electrode is arranged on the first substrate, the driving electrode is arranged on the second substrate, and a plurality of the microchannels are formed between the first substrate and the second substrate by sealing.

[0014] Based on the further improvement of the above-mentioned microfluidic chip, the voltage-dividing acquisition circuit includes: an acquisition module and a plurality of first amplifying channels arranged in parallel, each of the first amplifying channels includes a first amplifier and a first AC-DC converter connected in series, and the amplification factor of the first amplifier of each first amplifying channel is different.

[0015] The acquisition module is used to acquire the voltage-dividing signal at both ends of the voltage-dividing element, the first amplifier is used to amplify the acquired voltage-dividing signal, and the first AC-to-DC element is used to convert the voltage-dividing signal amplified by the corresponding first amplifier from an AC signal to a DC signal and output it as a voltage-dividing signal measurement value.

[0016] Based on the further improvement of the above-mentioned microfluidic chip, the first AC-DC converter is an effective value chip, wherein the integration time of the effective value chip of each first amplification channel is set according to the amplification factor of the corresponding first amplifier.

[0017] Based on the further improvement of the above-mentioned microfluidic chip, the microfluidic chip further includes: a processing module,

[0018] The processing module is respectively connected to the output ends of the multiple first amplification channels of each of the voltage division acquisition circuits. The processing module selects the voltage division signal measurement value output by one of the first amplification channels as the effective measurement value of the voltage division signal collected by the voltage division acquisition circuit according to a preset threshold value, so as to obtain the movement position information of the droplets in the corresponding microchannel.

[0019] Based on the further improvement of the above-mentioned microfluidic chip, the microfluidic chip further includes: a driving voltage acquisition circuit,

[0020] The driving voltage acquisition circuit includes: an attenuation module, a second amplifier and a second AC-DC conversion element,

[0021] The attenuation module is used to collect and attenuate the driving voltage signal applied by the driving power supply, the second amplifier is used to amplify the attenuated driving voltage signal, and the second AC-DC element is used to convert the amplified driving voltage signal from an AC signal to a DC signal and output it as a driving voltage signal measurement value.

[0022] On the other hand, an embodiment of the present invention provides a method for monitoring a droplet state, which is implemented based on the microfluidic chip as described above, and the method includes:

[0023] The driving power supply applies a driving voltage to one or more driving electrodes to control the movement of liquid in one or more of the microchannels;

[0024] The voltage division signal corresponding to each microchannel is obtained through each voltage division acquisition circuit respectively;

[0025] Acquiring a driving voltage signal applied by a driving power source;

[0026] The equivalent capacitance value between electrodes of each microchannel is calculated according to the voltage division signal corresponding to each microchannel and the driving voltage signal of the driving power supply, so as to obtain the movement position information of the droplets in each microchannel.

[0027] Based on the further improvement of the above method, the step of obtaining the voltage division signal corresponding to each microchannel through each voltage division acquisition circuit includes:

[0028] In the voltage division acquisition circuit corresponding to each microchannel, the measurement values ​​of multiple voltage division signals are respectively obtained through the multiple first amplification channels thereof;

[0029] The measured value of the voltage-divided signal output by one of the first amplification channels is selected as the effective measured value of the voltage-divided signal corresponding to the microchannel according to a preset threshold.

[0030] Based on the further improvement of the above method, the equivalent capacitance value C between electrodes of each microchannel is calculated according to the following formula: d :

[0031]

[0032] Where U measureC is the effective measured value of the partial pressure signal corresponding to the microchannel, A C is the amplification factor of the effective measurement value of the voltage divider signal corresponding to the microchannel, Z is the impedance of the voltage divider element, U is the effective value of the driving voltage signal, and ω is the angular frequency of the driving voltage signal.

[0033] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0034] 1. In the present invention, the drive control and status monitoring of droplets in multiple microchannels of the microfluidic chip can be performed simultaneously, which is beneficial to improving the working efficiency of the microfluidic chip.

[0035] 2. In the present invention, the droplet driving work of the microfluidic chip under test will not be affected when collecting signals, and the real-time monitoring and judgment of the motion state of the droplets during the droplet driving process can be achieved, which is conducive to saving time.

[0036] 3. In the present invention, considering that the voltage divider signal at both ends of the voltage divider element has a large variation range, the voltage divider acquisition circuit adopts multiple parallel amplification channels with different amplification factors to acquire signals. When the front-end voltage divider signal changes, the signal value of any amplification channel can be read in real time on demand, which not only realizes the range requirements for measuring voltage signals of different amplitudes, but also avoids the delay of signal acquisition, thereby ensuring the speed and accuracy of signal reading.

[0037] 4. In the present invention, the back ends of multiple amplification channels of the voltage-dividing acquisition circuit are all processed and converted into DC signals using AC-DC conversion elements. Compared with the existing "point drawing method" of voltage signal point acquisition and resynthesis, it can more truly reflect the feedback voltage data and improve the accuracy of the feedback droplet driving information.

[0038] In the present invention, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present invention will be described in the subsequent description, and some advantages can become obvious from the description, or can be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

[0040] Figure 1 Schematic diagram of the structure of the microfluidic chip according to an embodiment of the present invention;

[0041] Figure 2 It is a schematic diagram of the structure for collecting the voltage division signal and the driving voltage signal of the microchannel according to an embodiment of the present invention;

[0042] Figure 3 It is a structural schematic diagram of a voltage division acquisition circuit according to an embodiment of the present invention;

[0043] Figure 4 Schematic diagram of the process of collecting voltage division signals according to an embodiment of the present invention;

[0044] Figure 5 It is a structural schematic diagram of a driving voltage acquisition circuit according to an embodiment of the present invention;

[0045] Figure 6 The figure is a flow chart of a driving voltage signal acquisition process according to an embodiment of the present invention.

[0046] Reference numerals:

[0047] 1. First substrate; 2. Second substrate; 3. Microchannel; 4. Common electrode;

[0048] 5. Driving electrode; 6. Voltage divider element; 7. Hydrophobic and dielectric layer. DETAILED DESCRIPTION

[0049] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0050] A microfluidic chip provided by an embodiment of the present invention, such as Figure 1 and Figure 2As shown in . The microfluidic chip comprises: a chip substrate, a plurality of voltage-dividing elements 6 and a plurality of voltage-dividing acquisition circuits. A plurality of microchannels 3 for accommodating droplets are formed on the chip substrate, and each of the microchannels 3 is respectively provided with an electrode group for controlling the movement of the droplets, and the electrode group comprises a common electrode 4 and a plurality of driving electrodes 5 arranged at intervals along the movement path of the droplets.

[0051] The driving power supply is respectively connected to all the driving electrodes 5, and the driving power supply applies the driving voltage to one or more driving electrodes 5 to control the movement of liquid in one or more of the microchannels 3; a voltage divider element 6 is respectively connected in series between the driving power supply and each of the common electrodes 4, and the voltage divider element 6 corresponds to the voltage divider acquisition circuit one by one, and each of the voltage divider acquisition circuits is respectively used to collect a voltage divider signal at both ends of the voltage divider element 6, wherein the movement position information of the droplets in each microchannel 3 is obtained according to the voltage divider signal collected by each voltage divider acquisition circuit and the driving voltage signal of the driving power supply.

[0052] Specifically, the voltage dividing element 6 includes a voltage dividing resistor or a voltage dividing capacitor.

[0053] In the process of droplet drive control of the microfluidic chip, it is necessary to monitor the state of the droplet movement position in real time to determine whether the chip is working properly. In implementation, after adding droplets to the microchannels 3 of the microfluidic chip, the electrodes between each microchannel 3 can be regarded as an equivalent capacitor, and the equivalent capacitance value changes during the movement of the microfluidic chip.

[0054] In an embodiment of the present invention, the electrode group of each microchannel 3, the corresponding voltage divider element 6 and the driving power supply are connected in series to form a loop, and the voltage divider signal at both ends of the voltage divider element 6 with a fixed impedance value is measured by a voltage divider acquisition circuit. The voltage between the electrodes of each microchannel 3 can be calculated in combination with the driving voltage signal of the driving power supply, and then its capacitance value can be obtained to determine the movement position information of the droplets in each microchannel 3.

[0055] Compared with the prior art, in the embodiment of the present invention, the droplets in multiple microchannels 3 of the microfluidic chip can be driven and controlled and the state is monitored at the same time, which is beneficial to improving the working efficiency of the microfluidic chip. At the same time, in the present invention, the droplet driving work of the microfluidic chip is not affected when collecting signals, and the real-time monitoring and judgment of the motion state of the droplets in the droplet driving process is realized, which is beneficial to saving time.

[0056] In one embodiment, the driving power source is connected to all the driving electrodes 5 via a switch array module, and the switch array module is used to enable the connection between one or more of the driving electrodes 5 and the driving power source.

[0057] Among them, the driving power supply provides the high-voltage AC signal required for droplet driving control. The driving power supply is connected to all driving electrodes 5 through a switch array. The switch array selects the driving voltage signal, thereby applying the driving voltage to the corresponding driving electrode 5 to drive the droplets in each microchannel 3 to move.

[0058] In one embodiment, Figure 1 As shown in the figure, the chip substrate includes a first substrate 1 and a second substrate 2 arranged opposite to each other, the common electrode 4 is arranged on the first substrate 1, the driving electrode 5 is arranged on the second substrate 2, and a plurality of microchannels 3 are formed between the first substrate 1 and the second substrate 2 by sealing.

[0059] Among them, the first substrate 1 and the second substrate 2 can both be glass substrates, and the common electrode 4 and the driving electrode 5 are prepared on the first substrate 1 and the second substrate 2 respectively using metal oxide (such as indium tin oxide ITO). After the electrodes are prepared, a hydrophobic and dielectric layer 7 is coated on the surface of the common electrode 4 and the driving electrode 5 respectively.

[0060] In one embodiment, the voltage-dividing acquisition circuit includes: an acquisition module and a plurality of first amplifying channels arranged in parallel, each of the first amplifying channels includes a first amplifier and a first AC-DC converter connected in series, and the amplification factor of the first amplifier of each first amplifying channel is different. The acquisition module is used to acquire the voltage-dividing signal at both ends of the voltage-dividing element 6, the first amplifier is used to amplify the acquired voltage-dividing signal, and the first AC-DC converter is used to convert the voltage-dividing signal amplified by the corresponding first amplifier from an AC signal to a DC signal and output it as a voltage-dividing signal measurement value.

[0061] In the embodiment of the present invention, considering that the voltage divider signal at both ends of the voltage divider element 6 has a large variation range, the voltage divider acquisition circuit adopts multiple parallel amplification channels with different amplification factors to acquire signals. When the front-end voltage divider signal changes, the signal value of any amplification channel can be read in real time on demand, which not only realizes the range requirements for measuring voltage signals of different amplitudes, but also avoids the delay of signal acquisition, thereby ensuring the speed and accuracy of signal reading.

[0062] At the same time, in the present invention, the back ends of multiple amplification channels of the voltage divider acquisition circuit are all processed and converted into DC signals using AC-DC conversion elements. Compared with the existing "point drawing method" of voltage signal point acquisition and resynthesis, it can more truly reflect the feedback voltage data and improve the accuracy of the feedback droplet state position information.

[0063] When implementing, Figure 3 and Figure 4As shown in , in the voltage-dividing acquisition circuit, the voltage-dividing signals at both ends of the voltage-dividing element 6 are acquired through the acquisition module, and the acquired voltage-dividing signals are connected to multiple (for example, three) first amplification channels with different amplification factors in parallel. Multiple channels simultaneously amplify the voltage-dividing signals. When the voltage-dividing signal at the front end changes, the signal value of any channel can be read as needed at any time, which not only realizes the range switching function required for measuring voltage signals of different amplitudes, but also ensures the speed and accuracy of signal reading. The back ends of multiple first amplification paths all use AC-to-DC elements for signal processing, complete the rectification and filtering to convert them into measurable DC signals, and the measured values ​​are more stable and reliable.

[0064] Specifically, the first AC-DC converter is an effective value chip, wherein the integration time of the effective value chip of each first amplification channel is set according to the amplification factor of the corresponding first amplifier.

[0065] Among them, the effective value chip can convert the AC voltage signal applied by the driving power supply into a measurable DC voltage signal through rectification and filtering, and the integration time of the effective value chip can be set, so as to effectively suppress the interference jitter and jump of the measurement signal, making the measurement value more stable and reliable.

[0066] During implementation, if the gain factor of the first amplifier of the first amplifier channel is larger, the effective value chip of the channel can be set to a longer integration time; if the gain factor of the first amplifier of the first amplifier channel is smaller, the effective value chip of the channel can be set to a shorter integration time.

[0067] Preferably, the voltage-dividing acquisition circuit further comprises: a first voltage follower. The first voltage follower is connected between the output end of the acquisition module and the input ends of the plurality of first amplification channels. Specifically, Figure 3 As shown in , the first voltage follower adopts an amplifier, and the first voltage follower is used for signal buffering and isolation to increase the load capacity.

[0068] In one embodiment, the microfluidic chip further includes: a processing module (e.g., a CPU processor). The processing module is respectively connected to the output ends of the plurality of first amplification channels of each of the voltage-dividing acquisition circuits, and the processing module selects a voltage-dividing signal measurement value output by one of the first amplification channels as a valid voltage-dividing signal measurement value collected by the voltage-dividing acquisition circuit according to a preset threshold value, so as to obtain the motion position information of the droplet in the corresponding microchannel 3.

[0069] In this embodiment, a voltage division signal measurement value within a suitable range is automatically selected by the processing module for calculating the current equivalent capacitance value of the microfluidic chip under test to obtain the motion position information of the droplet, which is conducive to ensuring the accuracy of the feedback droplet driving information.

[0070] Specifically, the value range of the preset threshold value can be set to 1 / 3 to 2 / 3 of the driving voltage value, preferably 1 / 2 of the driving voltage value. In other words, in the process of collecting the voltage division signal, the voltage division measurement values ​​obtained by traversing different first amplification channels are preferably the voltage division signal measurement value closest to 1 / 2 of the driving voltage value as the effective measurement value.

[0071] Preferably, the processing module comprises an analog-to-digital conversion unit, and the analog-to-digital conversion unit is used to convert the voltage-divided signals output by the plurality of first amplification channels from analog signals into digital signals respectively.

[0072] Specifically, Figure 4 As shown in , the voltage-dividing acquisition circuit includes: three first amplifying channels connected in parallel. The amplification factors of the first amplifiers of the three first amplifying channels are respectively set to 1, 10 and 100 times.

[0073] In one embodiment, the microfluidic chip further includes: a driving voltage acquisition circuit. The driving voltage acquisition circuit includes: an attenuation module, a second amplifier, and a second AC-DC element, wherein the second attenuation module is used to acquire and attenuate the driving voltage signal applied by the driving power supply, the second amplifier is used to amplify the attenuated driving voltage signal, and the second AC-DC element is used to convert the amplified driving voltage signal from an AC signal to a DC signal and output it as a driving voltage signal measurement value. Wherein, the effective value of the driving voltage signal is calculated based on the driving voltage signal measurement value.

[0074] In an embodiment of the present invention, the droplet drive information feedback sensing circuit is divided into two paths for voltage signal collection as a whole, which are used to measure the drive voltage signal applied by the drive power supply and the voltage divider signal at both ends of the voltage divider element 6 respectively. The equivalent capacitance of the chip after the droplet is added can be calculated through the collected signal measurement value, and then the real-time position state information during the droplet drive control process can be characterized.

[0075] The driving voltage acquisition circuit is used to collect and process the voltage signal of the driving power supply (high-voltage inverter power supply), and separate the driving voltage applied to the microfluidic chip into a single channel for signal acquisition. Figure 4 and Figure 5 as shown in .

[0076] It should be noted that the driving voltage signal applied by the driving power supply is a high-voltage AC signal. In order to measure the driving voltage signal, the driving voltage acquisition circuit of the embodiment of the present invention first attenuates the driving voltage signal through an attenuation module.

[0077] Specifically, Figure 6 As shown in , the attenuation coefficient of the attenuation module is set to 46.5 times, and the amplification factor of the second amplifier is set to 1 times.

[0078] Specifically, the second AC-DC converter is an effective value chip, and the integration time of the effective value chip is set according to the amplification factor of the corresponding second amplifier. The effective value chip can convert the AC voltage signal applied by the driving power supply into a measurable DC voltage signal through rectification and filtering, and the integration time of the effective value chip can be set, so as to effectively suppress the interference jitter and jump of the measurement signal, making the measurement value more stable and reliable.

[0079] Preferably, the driving voltage acquisition circuit further includes: a second voltage follower. The second voltage follower is connected between the output end of the attenuation module and the input end of the second amplifier. Specifically, Figure 5 As shown in , the second voltage follower adopts an amplifier, and the second voltage follower is used for signal buffering and isolation to increase the load capacity.

[0080] In an embodiment of the present invention, for the high-voltage AC signal of the drive control, the attenuation module uses resistance proportional attenuation to convert it into a signal within 5V. After the signal is attenuated, it is followed and amplified by the second voltage follower and the second amplifier to optimize the transmission signal quality. Then, the second AC to DC element (effective value chip) is used to rectify and filter the input signal and convert it into a DC signal. Finally, the analog-to-digital conversion unit (ADC) of the processing module completes the signal conversion and drives the voltage signal measurement value.

[0081] On the other hand, an embodiment of the present invention provides a method for monitoring a droplet state, which is implemented based on the microfluidic chip as described above, and the method includes:

[0082] Step 0, the driving power supply applies a driving voltage to one or more driving electrodes 5 to control the movement of liquid in one or more of the microchannels 3;

[0083] Step 1, respectively obtaining the divided voltage signal corresponding to each microchannel 3 through each divided voltage acquisition circuit;

[0084] Step 2, obtaining a driving voltage signal applied by a driving power source;

[0085] Step 3, calculating the equivalent capacitance between electrodes of each microchannel 3 according to the voltage division signal corresponding to each microchannel 3 and the driving voltage signal of the driving power supply, so as to obtain the movement position information of the droplets in each microchannel 3.

[0086] Specifically, step 1, obtaining the voltage division signal corresponding to each microchannel 3 through each voltage division acquisition circuit, includes:

[0087] Step 11, in the voltage division acquisition circuit corresponding to each microchannel 3, the measurement values ​​of multiple voltage division signals are respectively obtained through the multiple first amplification channels thereof;

[0088] Step 12: selecting, according to a preset threshold, a measurement value of the voltage-divided signal output by one of the first amplification channels as a valid measurement value of the voltage-divided signal corresponding to the microchannel 3 .

[0089] Specifically, in step 2, a driving voltage signal applied by a driving power source is acquired through a driving voltage acquisition circuit.

[0090] Specifically, in step 3, the equivalent capacitance value C between electrodes of each microchannel 3 is calculated according to the following formula: d :

[0091]

[0092] Where U measureC is the effective measured value of the voltage divider signal corresponding to microchannel 3, A C is the amplification factor of the effective measurement value of the voltage divider signal corresponding to the microchannel 3, Z is the impedance of the voltage divider element 6, U is the effective value of the driving voltage signal, and ω is the angular frequency of the driving voltage signal.

[0093] When the voltage divider element 6 is a voltage divider resistor, Z = R C , R C is the resistance value of the voltage divider resistor. When the voltage divider element 6 is the voltage divider element 6, C C is the capacitance value of the voltage divider element 6.

[0094] Specifically, the effective value U of the driving voltage signal is calculated according to the following formula:

[0095]

[0096] Where U measureV A is the measured value of the driving voltage signal, which is obtained through the driving voltage acquisition circuit; V is the amplification factor of the driving voltage signal measurement value; R2 / R1 is the attenuation coefficient. Figure 4 As shown in , R1 and R2 are the resistors in the attenuation module.

[0097] Furthermore, the equivalent capacitance C between the electrodes of the microchannel 3 is d The total calculation formula is as follows:

[0098]

[0099] Those skilled in the art will appreciate that all or part of the processes of the above-mentioned embodiments can be implemented by instructing related hardware through a computer program, and the program can be stored in a computer-readable storage medium, wherein the computer-readable storage medium is a disk, an optical disk, a read-only storage memory, or a random access memory, etc.

[0100] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A microfluidic chip, characterized in that: The microfluidic chip comprises: a chip substrate, a plurality of voltage-dividing elements and a plurality of voltage-dividing collection circuits, A plurality of microchannels for accommodating droplets are formed on the chip substrate, and each of the microchannels is respectively provided with an electrode group for controlling the movement of the droplets, and the electrode group includes a common electrode and a plurality of driving electrodes arranged at intervals along the movement path of the droplets; A driving power source is connected to all the driving electrodes respectively, and the driving power source applies a driving voltage to one or more driving electrodes to control the movement of liquid in one or more of the microchannels; A voltage divider element is connected in series between the driving power supply and each of the common electrodes. The voltage divider elements correspond to the voltage divider collection circuits one by one. Each of the voltage divider collection circuits is used to collect a voltage divider signal at both ends of the voltage divider element. The movement position information of the droplets in each microchannel is obtained according to the voltage division signal collected by each voltage division collection circuit and the driving voltage signal of the driving power supply.

2. The microfluidic chip according to claim 1, characterized in that: The driving power source is connected to all the driving electrodes via a switch array module, and the switch array module is used to enable the connection between one or more of the driving electrodes and the driving power source.

3. The microfluidic chip according to claim 1 or 2, characterized in that: The chip substrate comprises a first substrate and a second substrate which are arranged opposite to each other, the common electrode is arranged on the first substrate, the driving electrode is arranged on the second substrate, and a plurality of microchannels are formed between the first substrate and the second substrate by sealing glue.

4. The microfluidic chip according to claim 1 or 2, characterized in that: The voltage-dividing acquisition circuit includes: an acquisition module and a plurality of first amplifying channels arranged in parallel, each of the first amplifying channels includes a first amplifier and a first AC-DC converter connected in series, and the amplification factor of the first amplifier of each first amplifying channel is different. The acquisition module is used to acquire the voltage-dividing signal at both ends of the voltage-dividing element, the first amplifier is used to amplify the acquired voltage-dividing signal, and the first AC-to-DC element is used to convert the voltage-dividing signal amplified by the corresponding first amplifier from an AC signal to a DC signal and output it as a voltage-dividing signal measurement value.

5. The microfluidic chip according to claim 4, characterized in that: The first AC-to-DC element is an effective value chip, wherein the integration time of the effective value chip of each first amplification channel is set according to the amplification factor of the corresponding first amplifier.

6. The microfluidic chip according to claim 4, characterized in that: The microfluidic chip further comprises: a processing module, The processing module is respectively connected to the output ends of the multiple first amplification channels of each of the voltage division acquisition circuits. The processing module selects the voltage division signal measurement value output by one of the first amplification channels as the effective measurement value of the voltage division signal collected by the voltage division acquisition circuit according to a preset threshold value, so as to obtain the movement position information of the droplets in the corresponding microchannel.

7. The microfluidic chip according to claim 1 or 2, characterized in that: The microfluidic chip further comprises: a driving voltage acquisition circuit, The driving voltage acquisition circuit includes: an attenuation module, a second amplifier and a second AC-DC conversion element, The attenuation module is used to collect and attenuate the driving voltage signal applied by the driving power supply, the second amplifier is used to amplify the attenuated driving voltage signal, and the second AC-DC element is used to convert the amplified driving voltage signal from an AC signal to a DC signal and output it as a driving voltage signal measurement value.

8. A method for monitoring the state of a droplet, implemented based on the microfluidic chip according to any one of claims 1 to 7, characterized in that: The method comprises: The driving power supply applies a driving voltage to one or more driving electrodes to control the movement of liquid in one or more of the microchannels; The voltage division signal corresponding to each microchannel is obtained through each voltage division acquisition circuit respectively; Acquiring a driving voltage signal applied by a driving power source; The equivalent capacitance value between electrodes of each microchannel is calculated according to the voltage division signal corresponding to each microchannel and the driving voltage signal of the driving power supply, so as to obtain the movement position information of the droplets in each microchannel.

9. The method for monitoring the state of a droplet according to claim 8, characterized in that: The step of obtaining the voltage division signal corresponding to each microchannel through each voltage division acquisition circuit includes: In the voltage division acquisition circuit corresponding to each microchannel, the measurement values ​​of multiple voltage division signals are respectively obtained through the multiple first amplification channels thereof; The measured value of the voltage-divided signal output by one of the first amplification channels is selected as the effective measured value of the voltage-divided signal corresponding to the microchannel according to a preset threshold.

10. The method for monitoring the state of a droplet according to claim 8, characterized in that: The equivalent capacitance C between electrodes of each microchannel is calculated according to the following formula: d : Where U measureC is the effective measured value of the partial pressure signal corresponding to the microchannel, A C is the amplification factor of the effective measurement value of the voltage divider signal corresponding to the microchannel, Z is the impedance of the voltage divider element, U is the effective value of the driving voltage signal, and ω is the angular frequency of the driving voltage signal.

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