Digital microfluidic chip integrating myocardial tissue culture and multimodal detection

Abstract

The application discloses a digital microfluidic chip integrating myocardial tissue culture and multimode detection, and belongs to the microfluidic chip field.The digital microfluidic chip comprises a lower substrate, an upper substrate and a sealing gasket; the lower substrate and the upper substrate are connected through the sealing gasket around the lower substrate and the upper substrate, and a space for liquid drop flow is formed in the middle; the lower substrate is provided with a functionalized partition electrode array, which comprises a liquid storage area, an electrical physiological acquisition area and a biochemical detection area; the electrical physiological acquisition area adopts an MEA electrical physiological acquisition array and is used for acquiring field potential signals of myocardial tissue in situ; a recess for accommodating a solid-phase carrier is formed in an electrode of the biochemical detection area, and a myocardial injury marker is captured through the solid-phase carrier; the upper substrate is made of a transparent material and is provided with a channel communicating with the liquid storage area and the electrical physiological acquisition area; and the digital microfluidic chip drives liquid drops through a dielectric wetting effect, integrates myocardial tissue culture, electrical physiological signal monitoring and biochemical marker detection on the same chip, and realizes in-situ synchronous detection of electrical physiology and biochemistry in a dual-mode manner.

Description

Technical Field

[0001] This invention relates to the field of microfluidic chips, and more particularly to a digital microfluidic chip that integrates myocardial tissue culture and multimodal detection. Background Technology

[0002] Cardiotoxicity is a major cause of candidate drug failure and market withdrawal in drug development. Therefore, accurate and efficient cardiotoxicity screening in the preclinical stage is crucial. Current technologies mainly rely on traditional two-dimensional cell culture, animal models, and early microfluidic platforms. Traditional cell culture models struggle to simulate the physiological microenvironment of myocardial tissue, and their detection methods are limited, typically relying on cell viability or a single molecular marker, failing to reflect the overall functional state of cardiomyocytes, particularly their electrophysiological characteristics. While animal models can provide overall organ responses, they suffer from species differences, ethical constraints, and high costs. Recent advancements in microfluidic organ-on-a-chip technology, particularly for myocardial research, have made it possible to construct more physiologically relevant models in vitro. However, most existing myocardial microarrays remain functionally limited, focusing either on culture and morphological observation or only performing one of two methods: field potential measurement or biochemical detection. This fragmented detection approach is cumbersome, requires large sample volumes, and presents fragmented information, hindering multi-parameter, real-time, and comprehensive assessment of drug cardiotoxicity, thus impacting the accuracy and efficiency of screening.

[0003] In summary, the existing technologies have the following problems: First, the existing detection methods are limited, and the detection of electrophysiological signals and key biochemical markers are usually carried out separately, resulting in fragmented multidimensional information and difficulties in correlation analysis; Second, there is a lack of an automated platform that integrates tissue culture, multi-parameter in-situ synchronous detection and data analysis, which is cumbersome to operate, has low throughput, and makes it difficult to achieve real-time and comprehensive efficacy evaluation.

[0004] Therefore, the present invention develops a miniaturized and automated digital microfluidic chip platform that can integrate myocardial tissue culture and simultaneously realize multimodal detection of electrophysiological and molecular markers, which is of urgent need and great significance for promoting the development of cardiotoxicity screening technology. Summary of the Invention

[0005] The purpose of this invention is to address the problems of insufficient physiological relevance of existing cardiotoxicity evaluation models, limited detection methods, cumbersome operation, and fragmented multi-dimensional information, by providing a digital microfluidic chip that integrates myocardial tissue culture and multimodal detection. This solution aims to integrate the dynamic construction and long-term culture of myocardial tissue with in-situ and simultaneous detection of field potential signals and molecular markers, achieving automated operation and real-time multi-parameter correlation analysis to improve the physiological relevance, accuracy, and efficiency of drug cardiotoxicity screening.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A digital microfluidic chip integrating myocardial tissue culture and multimodal detection includes a lower electrode plate, an upper electrode plate, and a sealing gasket; the lower electrode plate and the upper electrode plate are connected around the perimeter by the sealing gasket, forming a space for droplet flow in the middle; the lower electrode plate is provided with a functionalized partitioned electrode array, including a liquid storage area, an electrophysiological acquisition area, and a biochemical detection area;

[0008] The electrophysiological acquisition area uses an MEA electrophysiological acquisition array to acquire field potential signals of myocardial tissue in situ; the electrodes of the biochemical detection area have pits for accommodating solid carriers to capture myocardial injury markers through the solid carriers.

[0009] The upper electrode plate is made of transparent material and has a channel that connects to the liquid storage area and the electrophysiological acquisition area.

[0010] The digital microfluidic chip drives droplets through dielectric wetting effect, and integrates myocardial tissue culture, electrophysiological signal monitoring and biochemical marker detection on the same chip, realizing in-situ synchronous detection of electrophysiological and biochemical dual modes.

[0011] The biochemical detection area includes detection sites corresponding to cardiac troponin I (cTnI), myoglobin (Myo), and creatine kinase isoenzyme (CK-MB), respectively; the solid carrier is a solid micro-block pre-coated with the corresponding detection antibodies Myo, cTnI, and CK-MB primary antibodies, which is fixed in the pit by physical embedding.

[0012] The storage area includes multiple reservoirs for independently storing cell suspensions, culture media, test drugs, and detection secondary antibodies; the digital microfluidic chip is configured to automatically drive droplets to complete the entire process of cell culture, drug administration, electrophysiological signal acquisition, and biochemical and immunological detection according to a preset droplet path plan.

[0013] The in-situ simultaneous detection of electrophysiological and biochemical dual modes refers to the continuous recording of changes in the field potential of myocardial tissue under drug stimulation during the same drug screening experiment. At the same time, the culture waste liquid containing myocardial injury markers generated by the drug stimulation is automatically driven to the biochemical detection area, captured by the solid-phase carrier, and detected by external fluorescence in real time through the upper electrode plate, thereby establishing an immediate correlation between electrophysiological abnormalities and the release of molecular markers.

[0014] The functionalized partitioned electrode array also includes a driving region for driving droplet movement.

[0015] The chip also integrates a temperature control module, which includes a thermistor integrated inside the chip and an external feedback circuit.

[0016] The chip also includes a signal processing link, which includes a low-noise operational amplifier and a filter circuit connected to the MEA electrophysiological acquisition array via a gold finger adapter board, for capturing microvolt-level field potential signals.

[0017] The application of a digital microfluidic chip integrating myocardial tissue culture and multimodal detection is described above, used to evaluate the cardiotoxicity of the test drug.

[0018] The application is as follows: First, cardiomyocyte suspension and culture medium are driven to the electrophysiological acquisition area for culture; then, drug droplets are driven to the electrophysiological acquisition area for cell co-culture, and the electrophysiological signals of the cells are acquired simultaneously; finally, the waste liquid after cell co-culture is driven sequentially to the Myo, cTnI and CK-MB myocardial marker detection areas, and secondary antibody droplets are removed from the corresponding Myo, cTnI and CK-MB secondary antibody reservoirs to the corresponding detection areas for immune response, thereby assessing the cardiotoxicity of the test drug.

[0019] A method for screening drug cardiotoxicity based on the aforementioned digital microfluidic chip includes the following steps:

[0020] 1) Myocardial tissue construction and culture: Myocardial cell suspension droplets are moved from the myocardial cell suspension reservoir to the electrophysiological acquisition area where the MEA electrophysiological acquisition array is located. Culture medium is continuously supplied through the culture medium reservoir, and myocardial tissue is dynamically constructed and cultured for a long time under the physiological temperature conditions maintained by the temperature control module.

[0021] 2) Synchronous monitoring of drug stimulation and electrophysiology: The drug droplets to be tested are moved from the drug reservoir to the electrophysiological acquisition area and co-cultured with myocardial tissue. At the same time, the field potential signal of myocardial tissue is synchronously acquired through the MEA electrophysiological acquisition array to record the dynamic changes of electrophysiological activity under the action of drugs.

[0022] 3) In-situ capture of myocardial markers: The waste liquid droplets after drug co-culture are sequentially moved from the electrophysiological acquisition area to the biochemical detection area where the solid-phase carrier coated with the corresponding myocardial marker primary antibody is located, so that the myocardial marker in the waste liquid can specifically bind to the capture antibody on the solid-phase carrier;

[0023] 4) Immunoassay and fluorescence analysis: The corresponding enzyme-labeled or fluorescently labeled secondary antibody droplets are moved from the myocardial marker secondary antibody reservoir to the biochemical detection area, where they undergo an immunoassay with the solid-phase carrier that has captured the myocardial markers. Fluorescence detection is performed through the upper electrode plate to quantitatively analyze the myocardial marker content.

[0024] 5) Multiparameter correlation analysis: The electrophysiological signal time series data obtained in step 2) are correlated with the myocardial marker release time series data obtained in step 4) to assess the myocardial toxicity of the test drug.

[0025] Compared with the prior art, the beneficial effects achieved by the technical solution of this invention are:

[0026] 1. High integration and simultaneous multimodal detection: On a single digital microfluidic chip platform, it integrates dynamic construction of myocardial tissue, long-term culture, programmed drug stimulation, in situ monitoring of electrophysiological signals (field potentials), and biochemical detection of key myocardial biomarkers, solving the core problems of traditional methods such as single detection dimensions and fragmented operation processes.

[0027] 2. Through precise digital drive of microdroplets, the entire process of cultivation and detection is fully automated and programmed, significantly improving the repeatability and throughput of experiments;

[0028] 3. Real-time, in-situ, and synchronous acquisition of multiple parameters (electrophysiological and biochemical indicators) makes it possible to analyze the correlation between myocardial tissue function and structural damage under drug action, greatly improving the accuracy of cardiotoxicity assessment and early warning capabilities, and providing a more physiologically relevant and information-rich efficient platform for drug screening. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall structure of a microfluidic chip.

[0030] Figure 2 This is a schematic diagram of the exploded structure of a digital microfluidic chip.

[0031] Figure 3 This is a schematic diagram of the structure of the functionalized partitioned electrode array for the lower electrode plate.

[0032] Figure 4 This is a schematic diagram of the MEA electrophysiological acquisition array.

[0033] Figure 5 This is a cross-sectional schematic diagram of the cardiac biomarker detection electrode of a digital microfluidic chip.

[0034] Figure 6 A schematic diagram illustrating the allocation of liquid reservoirs and droplet path planning for a digital microfluidic chip.

[0035] Figure 7 This is a product image of a digital microfluidic chip.

[0036] Figure 8 Microscopic images of stained cardiac fibroblasts cultured on a digital microfluidic chip.

[0037] Figure 9 The images show the fluorescence effects of cTnI immunoassay before and after detection using a digital microfluidic chip.

[0038] Figure reference numerals: upper electrode 1, lower electrode 2, sealing gasket 3, solid phase carrier 4, MEA electrophysiological acquisition array 21, pit 22, temperature sensor 23, gold finger adapter plate 24. Detailed Implementation

[0039] To make the technical problems, technical solutions and beneficial effects of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0040] This invention integrates a digital microfluidic chip for myocardial tissue culture and multimodal detection. Its core innovation lies in breaking the spatiotemporal separation between electrophysiological signals and molecular biological indicators in traditional drug toxicity evaluation, and constructing an automated multimodal monitoring platform for the entire life cycle.

[0041] First, by integrating an MEA electrophysiological acquisition array into a digital microfluidic (DMF) electrode array, non-destructive and real-time acquisition of field potential signals in myocardial tissue is achieved, filling the gap in electrophysiological monitoring under digital fluid manipulation.

[0042] Secondly, by embedding micro-pit structures in the electrode array and fixing functionalized solid carriers, the problem of accurate positioning and stability of solid carriers in an open microfluidic environment is solved, thereby realizing in-situ capture and fluorescence analysis of myocardial markers such as Myo, cTnI and CK-MB.

[0043] The "electro-chemical dual-modal" integrated solution provided by this invention aims to achieve an innovative design that seamlessly integrates and synchronously operates two different analytical techniques—electrophysiological signal monitoring and chemical molecular marker detection—on the same spatiotemporal scale on a digital microfluidic chip platform.

[0044] This "electrochemical dual-modal" integrated solution, combined with the chip's built-in closed-loop temperature control system and automated droplet drive, enables researchers to simultaneously observe the complete dynamic process of cardiomyocytes from abnormal electrophysiological activity to the release of molecular damage markers in a microsystem that highly simulates the in vivo physiological environment, significantly improving the accuracy and efficiency of drug screening.

[0045] Example 1

[0046] like Figures 1-7 As shown in the figure, this embodiment of a digital microfluidic chip integrating myocardial tissue culture and multimodal detection includes an upper electrode plate 1, a lower electrode plate 2 and a sealing gasket 3; the lower electrode plate and the upper electrode plate are connected around the perimeter by the sealing gasket, forming a space in the middle for droplet flow.

[0047] The lower electrode plate is constructed using a high-stability PCB process, and its surface is gold-plated to ensure the faithful transmission of bioelectrical signals. Its core lies in the layout of the functionalized partitioned electrode array, which includes a reservoir area, a driving area, an electrophysiological acquisition area, and a biochemical detection area.

[0048] The electrophysiological acquisition area (also known as the core culture area) employs an MEA electrophysiological acquisition array 21 for in-situ acquisition of field potential signals from myocardial tissue; such as Figure 4 As shown, a 3×3 distributed microelectrode array (φ300 μm) is used to directly couple with myocardial tissue to achieve high-fidelity capture of microvolt-level field potential signals.

[0049] The myocardial marker detection electrode in the biochemical detection area has a recess 22 for accommodating the solid carrier 4; the recess structure is precisely matched in size with the solid carrier to ensure that the immune capture site always maintains spatial stability during the frequent back-and-forth driving of the droplet.

[0050] The driving region is used to drive the movement of the droplet. Specifically, to ensure the smoothness of droplet driving, both the upper and lower electrodes are provided with hydrophobic layers, and the electrode surfaces are covered with a dielectric layer, thus creating a highly efficient driving performance.

[0051] The biochemical detection area includes detection sites corresponding to cardiac troponin I (cTnI), myoglobin (Myo), and creatine kinase isoenzyme (CK-MB), respectively. The solid-phase carrier is a solid micro-bulb pre-coated with the corresponding detection antibodies Myo, cTnI, and CK-MB primary antibodies, which is physically embedded in the pit of the lower electrode for detecting cardiac biomarkers. Under automated program control, the test droplet flows through this area, enabling in-situ specific capture and fluorescence detection of the biomarkers without interfering with electrophysiological monitoring.

[0052] See Figure 6 The storage area includes multiple reservoirs for independently storing cardiomyocyte suspensions, culture media, test drugs, and detection secondary antibodies. Additionally, a buffer zone and a waste zone are located on the lower electrode plate. The digital microfluidic chip is configured to automatically drive droplets to complete the entire process of cell culture, drug administration, electrophysiological signal acquisition, and biochemical and immunological detection according to a preset droplet path plan.

[0053] The upper electrode plate is made of a transparent material and has channels that connect to the liquid storage area and the electrophysiological acquisition area; specifically, a vent is provided above the electrophysiological acquisition area (see...). Figures 1-2 , Figure 4 and Figure 7 An injection port is provided above the corresponding storage area (see [link]). Figures 1-2 and Figure 7In addition, the upper electrode plate is provided with diagonally arranged oil injection holes and oil outlet holes, as well as conductive silver paste holes. In this embodiment, 0.8 mm ITO conductive glass is used, which not only provides a global grounding reference potential, but also supports real-time fluorescence detection of the markers captured in the pit by external fluorescence detection equipment due to its high transparency.

[0054] To ensure the long-term viability and signal quality of myocardial tissue, this embodiment incorporates several technical compensations in its detailed design. Regarding thermal management, a thermistor 23 is integrated within the chip, working in conjunction with an external feedback circuit to achieve precise temperature control of ±0.1℃, ensuring that the myocardial tissue maintains physiological homeostasis even during dynamic operations such as fluid changes or drug administration. In terms of signal transmission, the MEA electrophysiological acquisition array, through an external gold finger adapter board 24, is coupled to a low-noise operational amplifier and filter circuit, enabling it to capture weak field potential changes at the microvolt level.

[0055] Example 2

[0056] In this embodiment, the digital microfluidic chip drives droplets through dielectric wetting effect, and integrates myocardial tissue culture, electrophysiological signal monitoring and biochemical marker detection on the same chip, realizing in-situ synchronous detection of electrophysiological and biochemical dual modalities.

[0057] The in-situ simultaneous detection of electrophysiological and biochemical dual modes refers to the continuous recording of changes in the field potential of myocardial tissue under drug stimulation during the same drug screening experiment. At the same time, the culture waste liquid containing myocardial injury markers generated by the drug stimulation is automatically driven to the biochemical detection area, captured by the solid-phase carrier, and detected by external fluorescence in real time through the upper electrode plate, thereby establishing an immediate correlation between electrophysiological abnormalities and the release of molecular markers.

[0058] First, cardiomyocyte suspension and culture medium are driven to the electrophysiological acquisition area for culture. Then, drug droplets are driven to the electrophysiological acquisition area for cell co-culture, and the electrophysiological signals of the cells are collected simultaneously. Finally, the waste liquid after cell co-culture is driven sequentially to the Myo, cTnI and CK-MB myocardial marker detection areas, and secondary antibody droplets are removed from the corresponding Myo, cTnI and CK-MB secondary antibody reservoirs to the corresponding detection areas for immune response, thereby assessing the cardiotoxicity of the test drugs.

[0059] Specifically, such as Figure 6 As shown, droplet path planning clearly demonstrates the fully automated operation from cell culture to drug screening and detection, including the following steps:

[0060] 1) Myocardial tissue construction and culture: Myocardial cell suspension droplets are moved from the myocardial cell suspension reservoir to the electrophysiological acquisition area where the MEA electrophysiological acquisition array is located. Culture medium is continuously supplied through the culture medium reservoir, and myocardial tissue is dynamically constructed and cultured for a long time under the physiological temperature conditions maintained by the temperature control module.

[0061] 2) Synchronous monitoring of drug stimulation and electrophysiology: The drug droplets to be tested are moved from the drug reservoir to the electrophysiological acquisition area and co-cultured with myocardial tissue. At the same time, the field potential signal of myocardial tissue is synchronously acquired through the MEA electrophysiological acquisition array to record the dynamic changes of electrophysiological activity under the action of drugs.

[0062] 3) In-situ capture of myocardial markers: The waste liquid droplets after drug co-culture are sequentially moved from the electrophysiological acquisition area to the Myo, cTnI and CK-MB myocardial marker detection electrodes containing solid carriers coated with the corresponding myocardial marker primary antibodies, so that the myocardial markers in the waste liquid can specifically bind to the capture antibodies on the solid carriers;

[0063] 4) Immunoassay and fluorescence analysis: The corresponding enzyme-labeled or fluorescently labeled secondary antibody droplets are moved from the myocardial marker secondary antibody reservoir to the corresponding detection electrode, where they undergo an immunoassay with the solid-phase carrier that has captured the myocardial markers. Fluorescence detection is performed through the upper electrode plate to quantitatively analyze the myocardial marker content.

[0064] 5) Multiparameter correlation analysis: The electrophysiological signal time series data obtained in step 2) are correlated with the myocardial marker release time series data obtained in step 4) to assess the myocardial toxicity of the test drug.

[0065] like Figure 8 The image shown is a micrograph of a cultured cardiomyocyte fibroblast culturation using a digital microfluidic chip, demonstrating the good biocompatibility of the digital microfluidic chip. Figure 9 The fluorescence intensity diagrams of the solid-phase carrier of the digital microfluidic chip before and after cTnI immunoassay show that the solid-phase carrier in the myocardial marker detection electrode can effectively capture the corresponding myocardial markers in the droplets, which can be used to determine the content of myocardial markers in the droplets and then evaluate the myocardial toxicity of the test drug.

Claims

1. A digital microfluidic chip integrating myocardial tissue culture and multimodal detection, characterized in that: It includes a lower electrode plate, an upper electrode plate, and a sealing gasket; the lower electrode plate and the upper electrode plate are connected around the perimeter by the sealing gasket, forming a space in the middle for droplet flow; the lower electrode plate is provided with a functionalized partitioned electrode array, including a liquid storage area, an electrophysiological acquisition area, and a biochemical detection area; The electrophysiological acquisition area uses an MEA electrophysiological acquisition array to acquire field potential signals of myocardial tissue in situ; the electrodes of the biochemical detection area have pits for accommodating solid carriers to capture myocardial injury markers through the solid carriers. The upper electrode plate is made of transparent material and has a channel that connects to the liquid storage area and the electrophysiological acquisition area. The digital microfluidic chip drives droplets through dielectric wetting effect, and integrates myocardial tissue culture, electrophysiological signal monitoring and biochemical marker detection on the same chip, realizing in-situ detection of electrophysiological and biochemical dual modalities.

2. The digital microfluidic chip integrating myocardial tissue culture and multimodal detection as described in claim 1, characterized in that: The biochemical detection area includes detection sites corresponding to cardiac troponin I (cTnI), myoglobin (Myo), and creatine kinase isoenzyme (CK-MB), respectively; the solid carrier is a solid micro-block pre-coated with the corresponding detection antibodies Myo, cTnI, and CK-MB primary antibodies, which is fixed in the pit by physical embedding.

3. The digital microfluidic chip integrating myocardial tissue culture and multimodal detection as described in claim 1, characterized in that: The storage area includes multiple reservoirs for independently storing cell suspensions, culture media, test drugs, and detection secondary antibodies; the digital microfluidic chip is configured to automatically drive droplets to complete the entire process of cell culture, drug administration, electrophysiological signal acquisition, and biochemical and immunological detection according to a preset droplet path plan.

4. The digital microfluidic chip integrating myocardial tissue culture and multimodal detection as described in claim 1, characterized in that: The in-situ detection of the electrophysiological and biochemical dual modalities refers to the continuous recording of changes in the field potential of myocardial tissue under drug stimulation during the same drug screening experiment. At the same time, the culture waste liquid containing myocardial injury markers generated by the drug stimulation is automatically driven to the biochemical detection area, captured by the solid-phase carrier, and detected by external fluorescence in real time through the upper electrode plate, thereby establishing an immediate correlation between electrophysiological abnormalities and the release of molecular markers.

5. The digital microfluidic chip integrating myocardial tissue culture and multimodal detection as described in claim 1, characterized in that: The functionalized partitioned electrode array also includes a driving region for driving droplet movement.

6. The digital microfluidic chip integrating myocardial tissue culture and multimodal detection as described in claim 1, characterized in that: The chip also integrates a temperature control module, which includes a thermistor integrated inside the chip and an external feedback circuit.

7. The digital microfluidic chip integrating myocardial tissue culture and multimodal detection as described in claim 1, characterized in that: The chip also includes a signal processing link, which includes a low-noise operational amplifier and a filter circuit connected to the MEA electrophysiological acquisition array via a gold finger adapter board, for capturing microvolt-level field potential signals.

8. The application of the digital microfluidic chip integrating myocardial tissue culture and multimodal detection as described in any one of claims 1 to 7, characterized in that: Used to assess the cardiotoxicity of the test drug.

9. The application as described in claim 8, characterized in that: First, cardiomyocyte suspension and culture medium are driven to the electrophysiological acquisition area for culture. Then, drug droplets are driven to the electrophysiological acquisition area for cell co-culture, and the electrophysiological signals of the cells are collected simultaneously. Finally, the waste liquid after cell co-culture is driven sequentially to the Myo, cTnI and CK-MB myocardial marker detection areas, and secondary antibody droplets are removed from the corresponding Myo, cTnI and CK-MB secondary antibody reservoirs to the corresponding detection areas for immune response, thereby assessing the cardiotoxicity of the test drug.

10. A method for screening drug cardiotoxicity based on the digital microfluidic chip according to any one of claims 1 to 7, characterized in that, Includes the following steps: 1) Myocardial tissue construction and culture: Myocardial cell suspension droplets are moved from the myocardial cell suspension reservoir to the electrophysiological acquisition area where the MEA electrophysiological acquisition array is located. Culture medium is continuously supplied through the culture medium reservoir, and myocardial tissue is dynamically constructed and cultured for a long time under the physiological temperature conditions maintained by the temperature control module. 2) Synchronous monitoring of drug stimulation and electrophysiology: The drug droplets to be tested are moved from the drug reservoir to the electrophysiological acquisition area and co-cultured with myocardial tissue. At the same time, the field potential signal of myocardial tissue is synchronously acquired through the MEA electrophysiological acquisition array to record the dynamic changes of electrophysiological activity under the action of drugs. 3) In-situ capture of myocardial markers: The waste liquid droplets after drug co-culture are sequentially moved from the electrophysiological acquisition area to the biochemical detection area where the solid-phase carrier coated with the corresponding myocardial marker primary antibody is located, so that the myocardial marker in the waste liquid can specifically bind to the capture antibody on the solid-phase carrier; 4) Immunoassay and fluorescence analysis: The corresponding enzyme-labeled or fluorescently labeled secondary antibody droplets are moved from the myocardial marker secondary antibody reservoir to the biochemical detection area, where they undergo an immunoassay with the solid-phase carrier that has captured the myocardial markers. Fluorescence detection is performed through the upper electrode plate to quantitatively analyze the myocardial marker content. 5) Multiparameter correlation analysis: The electrophysiological signal time series data obtained in step 2) are correlated with the myocardial marker release time series data obtained in step 4) to assess the myocardial toxicity of the test drug.

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