Microfluidic chip and droplet state monitoring method

Abstract

The present application relates to a kind of microfluidic chip and droplet state monitoring method, belong to microfluidic chip technical field, solve the problem that multiple channels of microfluidic chip cannot be simultaneously driven control and state monitoring in prior art.The microfluidic chip of the present application includes: chip matrix, multiple voltage dividing elements and multiple voltage dividing acquisition circuits, multiple microchannels are formed on chip matrix, each microchannel is respectively correspondingly provided with an electrode group, and the electrode group includes one common electrode and multiple drive electrodes;Driving power supply is respectively connected with all drive electrodes;Driving power supply and each common electrode are respectively connected with one voltage dividing element in series, and voltage dividing element and voltage dividing acquisition circuit correspond one by one, and each voltage dividing acquisition circuit is respectively used to collect the voltage division signal at both ends of one voltage dividing element.The present application realizes the simultaneous driving control and state monitoring of multiple channels of microfluidic chip, improves the accuracy of the feedback droplet state position information.

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 various 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 movement position information during the drive process, are important links in realizing the functions of the chip and even the microfluidic device. Real-time monitoring and feedback of the droplet movement status can enable equipment operators to judge the working status of the microfluidic chip, reflect whether the droplets move normally according to the planned movement path, and judge whether the droplet movement position is correct, so that when abnormal droplet movement occurs in the chip, the cause can be promptly identified and adjustment measures can be taken.

[0003] Currently, most real-time monitoring schemes for droplet motion in microfluidic chips use capacitance values ​​collected by capacitance detection circuits to determine droplet position. Some hardware circuits use timers to time-share the voltage drive circuit and capacitance detection circuit. Since the voltage drive circuit and capacitance detection circuit cannot operate simultaneously, the droplet drive control must be stopped during capacitance detection, which consumes a considerable amount of time and resources. Furthermore, existing capacitance detection circuits suffer from high interference and slow detection speeds.

[0004] Since changes in capacitance will cause changes in the corresponding voltage signal, the existing technology also monitors the state of droplet movement through a voltage acquisition circuit. For example, in the existing droplet drive information feedback sensing circuit, a method (point-tracing 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 voltage signal changes caused by capacitance changes, the existing acquisition method uses range switching to ensure that signals of different sizes can be accurately identified. However, the range switching time of this method is long, resulting in the range switching during the droplet movement not keeping up with the change in equivalent capacitance, which will cause delays in voltage signal data acquisition 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 application aim to provide a microfluidic chip and a droplet state monitoring method to solve the problem that the prior art cannot simultaneously drive control and state monitoring of multiple channels of a microfluidic chip and the accuracy of the acquired droplet motion position information is low and real-time performance is poor.

[0007] In one aspect, the embodiments of the present application provide a microfluidic chip, comprising: a chip substrate, a plurality of voltage division elements, and a plurality of voltage division acquisition circuits,

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

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

[0010] A voltage division element is connected in series between the drive power source and each common electrode, and the voltage division element corresponds to the voltage division acquisition circuit one-to-one, and each voltage division acquisition circuit is used to acquire the voltage division signal between the voltage division element,

[0011] Wherein, the motion position information of the droplets in each microchannel is obtained according to the voltage division signal acquired by each voltage division acquisition circuit and the drive voltage signal of the drive power source.

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

[0013] Based on the further improvement of the above-mentioned microfluidic chip, the chip substrate comprises a first substrate and a second substrate arranged oppositely, the common electrode is arranged on the first substrate, the drive electrode is arranged on the second substrate, and the first substrate and the second substrate form a plurality of microchannels through encapsulation.

[0014] Based on the further improvement of the above-mentioned microfluidic chip, the voltage division acquisition circuit comprises: an acquisition module and a plurality of first amplification channels arranged in parallel, each first amplification channel comprises a first amplifier and a first AC-DC element connected in series, and the amplification coefficients of the first amplifiers of each first amplification channel are different,

[0015] The acquisition module is configured to acquire a voltage division signal across the voltage division element, the first amplifier is configured to amplify the acquired voltage division signal, and the first AC-to-DC element is configured to convert the amplified voltage division signal from an AC signal to a DC signal and output the DC signal as a voltage division signal measurement value.

[0016] Based on the further improvement of the microfluidic chip, 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.

[0017] Based on the further improvement of the microfluidic chip, the microfluidic chip further comprises a processing module,

[0018] The processing module is connected to the output end of each first amplification channel of each voltage division acquisition circuit, and 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 acquired by the voltage division acquisition circuit according to a preset threshold, so as to obtain the motion position information of the droplet in the corresponding microchannel.

[0019] Based on the further improvement of the microfluidic chip, the microfluidic chip further comprises a driving voltage acquisition circuit,

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

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

[0022] In another aspect, the embodiment of the present application provides a droplet state monitoring method, which is realized based on the microfluidic chip as described above, and the method comprises the following steps:

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

[0024] Each microchannel corresponds to a voltage division acquisition circuit, and each voltage division acquisition circuit comprises a plurality of first amplification channels,

[0025] The driving voltage signal applied by the driving power supply is acquired;

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

[0027] Based on the further improvement of the above method, the acquisition of the partial voltage signal corresponding to each micro-channel by each partial voltage acquisition circuit comprises:

[0028] In the partial voltage acquisition circuit corresponding to each micro-channel, the measurement values of the plurality of partial voltage signals are respectively acquired through the plurality of first amplification channels thereof;

[0029] According to the preset threshold, the measurement value of the partial voltage signal output by one of the first amplification channels is selected as the effective measurement value of the partial voltage signal corresponding to the micro-channel.

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

[0031]

[0032] In the formula, U measureC is the effective measurement value of the partial voltage signal corresponding to the micro-channel, A C is the amplification coefficient of the effective measurement value of the partial voltage signal corresponding to the micro-channel, Z is the impedance of the partial voltage 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 application can at least achieve one of the following beneficial effects:

[0034] 1. In the present application, the liquid drops in the plurality of micro-channels of the micro-fluidic chip can be simultaneously driven and controlled and monitored, which is beneficial to improve the working efficiency of the micro-fluidic chip.

[0035] 2. In the present application, the signal acquisition does not affect the liquid drop driving work of the measured micro-fluidic chip, realizes real-time monitoring and judgment of the motion state of the liquid drop during the liquid drop driving process, and is beneficial to save time.

[0036] 3. In the present application, considering that the variation range of the partial voltage signal at both ends of the partial voltage element is large, the partial voltage acquisition circuit adopts a plurality of parallel amplification channels with different amplification factors to acquire signals, and when the front-end partial voltage signal changes, the signal value of any amplification channel can be read in real time as needed, which not only realizes the range requirement of measuring different amplitude voltage signals, but also avoids the delay of signal acquisition, and ensures the speed and accuracy of signal reading.

[0037] 4. In the present application, the rear end of the plurality of amplification channels of the partial voltage acquisition circuit is processed and converted into a direct current signal by an alternating current to direct current element, compared with the existing "point drawing method" of point acquisition and synthesis of voltage signals, the voltage data fed back can be more truly reflected, and the accuracy of the liquid drop driving information fed back is improved.

[0038] The technical solutions in the present application can be combined with each other to realize more preferred combination solutions. Other features and advantages of the present application will be described in the following description, and some advantages will become apparent from the description, or will be learned by practice of the present application. The objects and other advantages of the present application can be realized and obtained by the content particularly pointed out in the description and the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0039] The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the principles of the application. In the drawings:

[0040] Figure 1 Structure schematic view of microfluidic chip of the embodiment of the present application;

[0041] Figure 2 Structure schematic view of microchannel of the embodiment of the present application;

[0042] Figure 3 Structure schematic view of the voltage division acquisition circuit of the embodiment of the present application;

[0043] Figure 4 Flowchart of the voltage division signal acquisition process of the embodiment of the present application;

[0044] Figure 5 Structure schematic view of the driving voltage acquisition circuit of the embodiment of the present application;

[0045] Figure 6 Flowchart of the driving voltage signal acquisition process of the embodiment of the present application.

[0046] Reference signs:

[0047] 1, first substrate; 2, second substrate; 3, microchannel; 4, common electrode;

[0048] 5, driving electrode; 6, voltage division element; 7, hydrophobic and dielectric layer. DETAILED DESCRIPTION

[0049] The preferred embodiments of the present application will be described in detail below with reference to the drawings, which form a part of this application. The drawings together with the description are used to explain the principles of the present application and are not used to limit the scope of the present application.

[0050] The microfluidic chip provided by the embodiment of the present application is as shown in Figure 1 and Figure 2The microfluidic chip comprises a chip base, a plurality of voltage division elements 6 and a plurality of voltage division acquisition circuits. The chip base is provided with a plurality of microchannels 3 for accommodating liquid droplets, and each microchannel 3 is provided with an electrode group for controlling the movement of the liquid droplets, which comprises a common electrode 4 and a plurality of driving electrodes 5 arranged along the movement path of the liquid droplets.

[0051] A driving power source is connected with all the driving electrodes 5, and the driving power source applies a driving voltage to one or more driving electrodes 5 to control the movement of the liquid in one or more microchannels 3. A voltage division element 6 is connected in series between the driving power source and each common electrode 4, and the voltage division element 6 corresponds to the voltage division acquisition circuit. Each voltage division acquisition circuit is used to acquire the voltage division signal between the two ends of the voltage division element 6, and the movement position information of the liquid droplets in each microchannel 3 is obtained according to the voltage division signal acquired by each voltage division acquisition circuit and the driving voltage signal of the driving power source.

[0052] Specifically, the voltage division element 6 comprises a voltage division resistor or a voltage division capacitor.

[0053] During the driving control of the liquid droplets in the microfluidic chip, the movement position state of the liquid droplets needs to be monitored in real time to determine whether the chip is working normally. In the implementation, after the liquid droplets are added into the microchannels 3 of the microfluidic chip, the electrodes of each microchannel 3 can be regarded as an equivalent capacitor, and the equivalent capacitance value changes during the movement of the liquid droplets.

[0054] In the embodiment of the application, the electrode group of each microchannel 3, the corresponding voltage division element 6 and the driving power source are connected in series to form a loop, the voltage division signal between the two ends of the voltage division element 6 with a fixed impedance value is measured by the voltage division acquisition circuit, and the voltage between the electrodes of each microchannel 3 can be calculated in combination with the driving voltage signal of the driving power source, so as to obtain the capacitance value and determine the movement position information of the liquid droplets in each microchannel 3.

[0055] Compared with the prior art, in the embodiment of the application, the liquid droplets in a plurality of microchannels 3 of the microfluidic chip can be driven and controlled and monitored at the same time, which is beneficial to improve the working efficiency of the microfluidic chip. At the same time, in the application, the signal acquisition will not affect the driving work of the liquid droplets in the microfluidic chip, the movement state of the liquid droplets during the driving process can be monitored and determined in real time, which is beneficial to save time.

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

[0057] The driving power supply provides a high-voltage alternating current signal required for droplet driving control, and the driving power supply is connected with all the driving electrodes 5 through a switch array, the switch array selects the driving voltage signal, and thus the driving voltage is applied to the corresponding driving electrode 5 to drive the droplet in each microchannel 3 to move.

[0058] In one embodiment, as shown in Figure 1 The chip substrate comprises a first substrate 1 and a second substrate 2 arranged oppositely, 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 through encapsulation.

[0059] The first substrate 1 and the second substrate 2 can both be glass substrates, the common electrode 4 and the driving electrode 5 are prepared on the first substrate 1 and the second substrate 2 respectively by using metal oxide (for example, indium tin oxide ITO), and a hydrophobic layer and a medium layer 7 are coated on the surfaces of the common electrode 4 and the driving electrode 5 respectively after the electrodes are prepared.

[0060] In one embodiment, the voltage division acquisition circuit comprises an acquisition module and a plurality of first amplification channels arranged in parallel, and each first amplification channel comprises a first amplifier and a first AC-DC element connected in series, and the amplification coefficients of the first amplifiers of the first amplification channels are different. The acquisition module is used for acquiring the voltage division signal between the two ends of the voltage division element 6, the first amplifier is used for amplifying the acquired voltage division signal, and the first AC-DC element is used for converting the voltage division signal amplified by the corresponding first amplifier from an alternating current signal into a direct current signal and outputting the direct current signal as a voltage division signal measurement value.

[0061] In the embodiment of the application, considering that the voltage division signal between the two ends of the voltage division element 6 has a large variation range, the voltage division acquisition circuit adopts a plurality of amplification channels with different amplification multiples to acquire signals in parallel, and when the front-end voltage division signal changes, the signal value of any amplification channel can be read in real time as needed, which not only realizes the range requirement of measuring different amplitude voltage signals, but also avoids the delay of signal acquisition, thereby ensuring the speed and accuracy of signal reading.

[0062] Meanwhile, in the application, the rear ends of the plurality of amplification channels of the voltage division acquisition circuit are processed and converted into direct current signals by AC-DC elements, compared with the existing "point drawing method" of collecting and synthesizing voltage signal points, the voltage data fed back can be more truly reflected, and the accuracy of the position information of the droplet state fed back is improved.

[0063] In implementation, as shown in Figure 3 and Figure 4As shown in FIG. 1, in the voltage division acquisition circuit, the voltage division signal between the two ends of the voltage division element 6 is obtained by the acquisition module, and the acquired voltage division signal is respectively connected in parallel to multiple (for example, three) first amplification channels with different amplification factors. The multiple channels simultaneously amplify the voltage division signal. When the front-end voltage division signal changes, the signal value of any channel can be read at any time as needed, which not only realizes the range switching function required for measuring different amplitude voltage signals, but also ensures the speed and accuracy of signal reading. The rear end of the multiple first amplification channels adopts an AC-to-DC element for signal processing, completes rectification and filtering, and converts the signal into a measurable DC signal, which is more stable and reliable.

[0064] Specifically, 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.

[0065] 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, thereby effectively suppressing the interference jitter and jump of the measurement signal, making the measurement value more stable and reliable.

[0066] In implementation, if the amplification factor of the first amplifier of the first amplification channel is large, the effective value chip of the channel can be set to have a long integration time; if the amplification factor of the first amplifier of the first amplification channel is small, the effective value chip of the channel can be set to have a short integration time.

[0067] Preferably, the voltage division 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 end of the multiple first amplification channels. Specifically, as shown in FIG. 1, the first voltage follower is connected between the output end of the acquisition module and the input end of the multiple first amplification channels. Figure 3 As shown in FIG. 1, 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 comprises a processing module (for example, a CPU processor). The processing module is connected to the output end of each first amplification channel of each voltage division acquisition circuit, and 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 acquired by the voltage division acquisition circuit according to a preset threshold, which is used to obtain the motion position information of the droplet in the corresponding microchannel 3.

[0069] In this embodiment, one voltage division signal measurement value within a suitable range is automatically selected by the processing module to calculate the current equivalent capacitance value of the measured microfluidic chip to obtain the motion position information of the droplet, which is beneficial to ensure the accuracy of the feedback droplet driving information.

[0070] Specifically, 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 value obtained by traversing different first amplification channels is 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 for converting the voltage division signals output by the plurality of first amplification channels into digital signals.

[0072] Specifically, as shown in Figure 4 The voltage division acquisition circuit comprises three parallel first amplification channels. The amplification coefficients of the first amplifiers of the three first amplification channels are set to 1, 10 and 100 times, respectively.

[0073] In one embodiment, the microfluidic chip further comprises a driving voltage acquisition circuit. The driving voltage acquisition circuit comprises an attenuation module, a second amplifier and a second AC-DC element. 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. 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. The effective value of the driving voltage signal is calculated according to the driving voltage signal measurement value.

[0074] In the embodiment of the application, the droplet driving information feedback sensing circuit is divided into two paths for voltage signal acquisition as a whole, respectively for measuring the driving voltage signal applied by the driving power supply and the voltage division signal across the voltage division element 6. The equivalent capacitance of the chip after adding the droplet can be calculated through the measured signal, and the real-time position state information in the droplet driving control process can be represented.

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

[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 realize the measurement of the driving voltage signal, the driving voltage acquisition circuit in the embodiment of the application first attenuates the driving voltage signal through an attenuation module.

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

[0078] Specifically, the second AC-DC element is an effective value chip, and the integration time of the effective value chip is set according to the amplification coefficient of the corresponding second amplifier. Wherein, the effective value chip can convert the AC voltage signal applied by the driving power supply into a measurable DC voltage signal through rectification 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, and make the measurement value more stable and reliable.

[0079] Preferably, the driving voltage acquisition circuit further comprises 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, as shown in Figure 5 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 the embodiment of the present application, for the driving control high-voltage AC signal, the attenuation module adopts resistance proportional attenuation, and the signal is specifically changed to 5V, and after the signal attenuation, the second voltage follower and the second amplifier are used for following amplification to optimize the transmission signal quality, and then the second AC-DC element (effective value chip) is used to rectify and filter the input signal into a DC signal, and finally the analog-to-digital conversion unit (ADC) of the processing module completes the signal conversion, and the driving voltage signal measurement value.

[0081] On the other hand, the embodiment of the present application provides a droplet state monitoring method, which is realized based on the microfluidic chip as described above, and the method comprises:

[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 microchannels 3;

[0083] Step 1, respectively acquiring the corresponding voltage division signals of each microchannel 3 through each voltage division acquisition circuit;

[0084] Step 2, acquiring the driving voltage signal applied by the driving power supply;

[0085] Step 3, respectively calculating the inter-electrode equivalent capacitance values of each microchannel 3 according to the corresponding voltage division signals of each microchannel 3 and the driving voltage signal of the driving power supply, to obtain the movement position information of the droplets in each microchannel 3.

[0086] Specifically, step 1, the acquisition of the corresponding voltage division signals of each microchannel 3 through each voltage division acquisition circuit comprises:

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

[0088] Step 12: Select the measured value of the voltage-divided signal output by one of the first amplifying channels as the effective measured value of the voltage-divided signal corresponding to the microchannel 3 according to a preset threshold.

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

[0090] Specifically, in step 3, the equivalent capacitance 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 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 process steps of the above-described embodiments can be implemented by instructing related hardware through a computer program, and the program can be stored in a computer-readable storage medium, such as a magnetic disk, an optical disk, a read-only memory, or a random access memory.

[0100] The above description is only the preferred embodiment of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A microfluidic chip, characterized in that: The microfluidic chip includes: a chip substrate, multiple voltage-dividing elements and multiple voltage-dividing acquisition 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 spaced apart along the droplet movement path; A driving power supply is connected to all the driving electrodes respectively, and 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; 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 acquisition circuits one by one. Each of the voltage divider acquisition circuits is used to collect a voltage divider signal at both ends of the voltage divider element. The chip substrate includes a first substrate and a second substrate arranged opposite to each other, the common electrode is provided on the first substrate, the driving electrode is provided on the second substrate, a plurality of microchannels are formed between the first substrate and the second substrate by sealing, and the common electrode, microchannels and driving electrodes are spatially arranged in sequence, so that the driving power supply, the voltage divider element and the corresponding electrode group form a series circuit; The motion position information of the liquid droplets in each microchannel is acquired according to the divided voltage signal collected by each divided voltage 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 voltage-dividing acquisition circuit includes: an acquisition module and a plurality of first amplifying channels arranged in parallel, wherein 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-DC conversion 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.

4. The microfluidic chip according to claim 3, characterized in that 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.

5. The microfluidic chip according to claim 3, characterized in that: The microfluidic chip further comprises: a processing module, The processing module is respectively connected to the output ends of multiple first amplification channels of each of the voltage divider acquisition circuits. The processing module selects the voltage divider signal measurement value output by one of the first amplification channels as the effective measurement value of the voltage divider signal collected by the voltage divider acquisition circuit according to a preset threshold, so as to obtain the motion position information of the droplet in the corresponding microchannel.

6. The microfluidic chip according to claim 1 or 2, characterized in that: 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 converter. 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 into a DC signal and output it as a driving voltage signal measurement value.

7. A method for monitoring droplet status, implemented based on the microfluidic chip according to any one of claims 1 to 6, 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; Obtaining the voltage division signal corresponding to each microchannel through each voltage division acquisition circuit respectively; Acquiring a driving voltage signal applied by a driving power supply; 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 motion position information of the droplet in each microchannel.

8. The method for monitoring the state of a droplet according to claim 7, wherein: 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 the 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 amplifying channels is selected as the effective measured value of the voltage-divided signal corresponding to the microchannel according to a preset threshold.

9. The method for monitoring the state of a droplet according to claim 7, wherein: The equivalent capacitance C between the electrodes of each microchannel is calculated according to the following formula: d : Where U measureC is the effective measured value of the pressure divider 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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