Myocardial cell signal detection platform

Abstract

The invention discloses a myocardial cell signal detection platform, which is characterized in that an ordered fiber scaffold is integrated on a flexible layer of a second micro-beam structure, the extension direction of micro-beams is perpendicular to the extension direction of fibers, anisotropy of myocardial cells and a natural growth environment rich in micro-nano structures are simulated, and the cells are suspended and grow orderly without being limited by a plane substrate; the method is suitable for long-term stable culture and recording of electrophysiological signals of engineered myocardial tissues.

Description

Technical Field

[0001] The invention belongs to the technical field of bioengineering, and in particular relates to a myocardial cell signal detection platform. Background Art

[0002] Cardiovascular disease ranks first among the causes of death in humans, and drug-induced cardiotoxicity is the main reason for the failure of drug development. As an emerging preclinical screening method, myocardial chips have considerable potential in predicting drug-induced cardiotoxicity at an early stage and effectively reducing health risks in clinical applications. Cardiomyocytes have electrophysiological properties, and their electrophysiological signals can directly reflect the physiological state of cells. Cardiovascular diseases represented by arrhythmias and cardiotoxic drugs can cause changes in the electrophysiological signals of myocardial cells. It is becoming more and more common to detect the electrical properties of myocardial cells for drug screening, drug analysis, and analysis of disease models. In view of the special electrophysiological characteristics of myocardial cells, researchers have developed many tools or methods to characterize the electrophysiological parameters of myocardial cells.

[0003] Microelectrode array (MEA) has attracted great attention in the biomedical field as a non-invasive, highly flexible and high-resolution sensor device. MEA can obtain the extracellular field potential signal of cardiomyocytes by detecting the potential difference generated by the movement of ions across the membrane. In order to obtain cell electrophysiological signals more accurately and efficiently, researchers have conducted in-depth research on MEA.

[0004] MEAs prepared on rigid substrates are the most common tools for detecting electrophysiological signals of cardiomyocytes. Rigid substrates such as silicon and glass combine well with semiconductor technology and are still widely used. However, the biggest problem with rigid MEAs is that they do not match the mechanical properties of flexible biological tissues. The Young's modulus of silicon and glass, commonly used substrates for rigid MEAs, is in the GPa range, which is significantly mechanically mismatched with flexible myocardial tissues or cells with a Young's modulus of approximately 0.02-0.5MPa. Related studies have shown that substrates with significant differences in hardness from biological tissues can change the electromechanical behavior of immature cells, affecting cell morphology, contractility, and electrical signal transmission.

[0005] At present, using flexible materials as substrates to provide an environment that matches the modulus of myocardial tissue is a common method to improve the maturity of immature cardiomyocytes. Microelectrode arrays are prepared on flexible substrates such as PDMS and hydrogels using inkjet printing, screen printing and other technologies. They usually have good flexibility and stretchability and can maintain mechanical and electrical properties under repeated stretching cycles. However, there is an unavoidable problem that cells still grow on flexible substrates, which is inconsistent with their anisotropic and rich natural growth environment of micro-nano structures. In order to further simulate the natural growth environment of cardiomyocytes, researchers have achieved the restoration of the in vivo environment by constructing topographic cues and providing cell scaffolds. The topographic induction and protein induction of cells can be achieved on MEA using microcontact printing and micromolding methods, making the cells highly ordered, but from a microscopic perspective, single cells are still in an adherent state, and their growth and maturation are restricted. PLA / PCL scaffolds are prepared on the surface of rigid MEA to provide a more favorable environment for cardiomyocyte adhesion and growth, and more mature cell morphology can also be recorded. However, the method of promoting cell maturation by simply simulating the natural growth environment of cardiomyocytes still has limitations. A cardiomyocyte electrophysiological signal detection platform that can not only simulate the growth environment of cardiomyocytes to the greatest extent, but also provide stimulation to the cells, thereby further promoting the maturation of cell morphology and the expression of electromechanical behavior, needs to be developed urgently. This is crucial for the reliability of cardiotoxic drug detection. Summary of the invention

[0006] The purpose of the present invention is to provide a myocardial cell signal detection platform with a fiber scaffold-flexible microbeam complex, which can promote cell morphology and functional maturation and achieve long-term stable recording of electrophysiological signals of engineered myocardial tissue.

[0007] The technical solution of the present invention is as follows:

[0008] A cardiomyocyte signal detection platform includes a fiber scaffold-flexible microbeam complex, wherein the fiber scaffold-flexible microbeam complex is a first microbeam structure flexible layer, a metal microelectrode array, a second microbeam structure flexible layer and an ordered fiber scaffold stacked in sequence from bottom to top:

[0009] The first micro-beam structure flexible layer is hollowed out to form a plurality of parallel micro-beams, and the micro-beams extend in a first direction;

[0010] The metal microelectrode array includes a plurality of metal microelectrodes, each of which has a detection end and an interface end, wherein the detection end is electrically connected to the interface end, and the detection end array of the plurality of metal microelectrodes is arranged on the first microbeam structure flexible layer, and the interface end is arranged along the edge of the first microbeam structure flexible layer;

[0011] The second micro-beam structure flexible layer covers most of the surface of the metal micro-electrode array and exposes the detection end and the interface end;

[0012] The ordered fiber support comprises a plurality of fiber filaments arranged in a direction, wherein the fiber filaments extend in a second direction, and the first direction is perpendicular to the second direction.

[0013] In some preferred implementations, the density of the fiber filaments is 400-1000 filaments / mm, and the thickness of the ordered fiber scaffold is 3-10 μm.

[0014] In some preferred implementations, the method for preparing an ordered fiber scaffold on the second micro-beam structure flexible layer comprises the following steps:

[0015] ① Dissolve polycaprolactone in an organic solvent and stir until it is clear to obtain a fiber solution;

[0016] ② attaching the device including the second micro-beam structure flexible layer to the roller, and then spraying the fiber solution on the second micro-beam structure flexible layer by electrospinning to obtain a device integrated with an ordered fiber scaffold;

[0017] ③ The device integrated with the ordered fiber scaffold is removed from the drum, and the excess fiber filaments are removed to obtain a fiber scaffold-flexible microbeam complex;

[0018] Wherein, the extension direction of the micro-beams of the second micro-beam structure flexible layer is the axial direction of the roller;

[0019] The operating conditions of electrospinning are as follows: a voltage of 5 to 20 kV is applied to the spinneret, the drum is grounded, the relative distance between the drum and the spinneret is 10 to 30 cm, the propulsion speed of the fiber solution is 100 to 1000 μL / h, the rotation speed of the drum is 500 to 2000 rpm, and the electrospinning time is 5 to 20 min.

[0020] In some preferred implementations, the micro-beams are straight-line, broken-line, or curved.

[0021] In some preferred implementations, the width of the microbeam is 400-1000 μm, and the distance between two adjacent microbeams is 1-1.5 mm.

[0022] In some preferred implementations, the thickness of the first micro-beam structure flexible layer is 200-500 μm, and the thickness of the second micro-beam structure flexible layer is 10-20 μm.

[0023] In some preferred implementations, the thickness of the metal microelectrode is 100-500 nm, the characteristic size of the detection end is 50-200 μm, the distance between two adjacent detection ends is 400-2000 μm, and the characteristic size of the interface end is 1-2 mm.

[0024] In some preferred implementations, the metal microelectrode is a thin film made of an inert noble metal, and the detection end and the interface end are two opposite ends of the thin film.

[0025] In some preferred implementations, the cardiomyocyte signal detection platform further includes two culture chambers arranged opposite to each other;

[0026] The culture chamber has a cavity with a depth of 2 to 5 mm and a volume of 5 to 15 mm, and the cavities of the two culture chambers are arranged opposite to each other;

[0027] The fiber scaffold-flexible micro-beam complex is arranged between the two culture cavities and is irreversibly bonded to the two culture cavities respectively.

[0028] In some preferred implementations, the cavity is a pneumatic chamber.

[0029] In some preferred implementations, the material of the fiber filaments is polycaprolactone.

[0030] In some preferred implementations, the material of the first micro-beam structure flexible layer is polydimethylsiloxane.

[0031] In some preferred implementations, the material of the second micro-beam structure flexible layer is polydimethylsiloxane.

[0032] In some preferred implementations, the metal microelectrode is made of platinum or gold.

[0033] In some preferred implementations, the method for preparing the fiber scaffold-flexible micro-beam complex comprises the following steps:

[0034] (1) preparing a first flexible layer;

[0035] (2) preparing a metal microelectrode array on the surface of the first flexible layer by magnetron sputtering;

[0036] (3) forming a plurality of micro-beams on the first flexible layer by laser cutting to obtain a first micro-beam structure flexible layer provided with a metal micro-electrode array;

[0037] (4) preparing a second microbeam structure flexible layer on the surface of the first microbeam structure flexible layer provided with a metal microelectrode array by electrostatic spraying, and selectively exposing the detection end and the interface end of the metal microelectrode array to obtain a device including the second microbeam structure flexible layer;

[0038] (5) An ordered fiber scaffold is prepared on the second microbeam structure flexible layer by electrospinning to obtain a fiber scaffold-flexible microbeam complex.

[0039] In some preferred implementations, the specific operation of step (1) is: mixing polydimethylsiloxane with a curing agent to obtain a polymer solution, then placing the solution in a mold for curing, and demolding the solution to obtain a first flexible layer. In this embodiment, the curing agent is hydrogenated silicone oil, the amount of the curing agent added is 10-15wt%, the curing temperature is 80-90°C, and the curing time is 30-40min.

[0040] In some preferred implementations, the specific operation of step (2) is: covering the surface of the first flexible layer with a mask plate to expose only the position corresponding to the metal microelectrode array, and then placing the first flexible layer covered with the mask plate in a magnetron sputtering machine for sputtering, with a sputtering power of 150 W and a sputtering time of 20 to 60 minutes, removing the mask plate, and obtaining the first flexible layer provided with a metal microelectrode array.

[0041] In some preferred implementations, the specific operation of step (3) is: designing a drawing of the first micro-beam structure flexible layer, then importing the drawing into a laser processing device and laser cutting the first flexible layer provided with the metal micro-electrode array. After the cutting is completed, ultrasonic cleaning is performed with anhydrous ethanol for 10 to 20 minutes to remove surface chips, thereby obtaining the first micro-beam structure flexible layer provided with the metal micro-electrode array.

[0042] In some preferred implementations, the specific operations of step (4) are:

[0043] ① Dilute the polymer solution of polydimethylsiloxane and curing agent with a diluent;

[0044] ② Covering the surface of the first micro-beam structure flexible layer provided with the metal micro-electrode array with a mask plate, the mask plate covers the detection end and the interface end of the metal micro-electrode array and exposes the corresponding shape of the second micro-beam structure flexible layer;

[0045] ③ Apply a voltage of 5 to 20 kV to the spray needle, the mask plate is grounded, the relative distance between the spray needle and the mask plate is 10 to 30 cm, the propulsion speed of the diluted polymer solution is 100 to 500 μL / h, and the spray time is 20 to 40 min;

[0046] ④ Place the sprayed device at 80-90° C. for constant temperature curing for 30-40 minutes, then remove the mask plate to obtain a device including a second micro-beam structure flexible layer.

[0047] In some preferred implementations, the specific operation of irreversibly bonding the fiber scaffold-flexible microbeam complex to the culture chamber is: the fiber scaffold-flexible microbeam complex and the two culture chambers are plasma treated for 50 to 100 seconds respectively, and then positioned and attached and placed in a constant temperature box at 40 to 50°C for 30 to 60 minutes to obtain a cardiomyocyte signal detection platform.

[0048] The present invention has at least the following beneficial effects:

[0049] 1. The cardiomyocyte signal detection platform provided by the present invention integrates an ordered fiber scaffold on the second microbeam structure flexible layer. The extension direction of the microbeam is perpendicular to the extension direction of the fiber filament, simulating the natural growth environment of the anisotropic cardiomyocytes rich in micro-nano structures, so that the cells can grow in suspension and in an orderly manner without being restricted by a planar substrate. It is suitable for long-term and stable recording of electrophysiological signals of engineered myocardial tissue.

[0050] 2. The fiber scaffold-flexible microbeam composite myocardial cell signal detection platform provided by the present invention forms microbeams on a polydimethylsiloxane flexible substrate through hollowing out to obtain a first microbeam structure flexible layer and a second microbeam structure flexible layer. The cells grown on the ordered fiber scaffold contract and drive the microbeams to undergo deflection changes. The presence of the microbeams has a certain resistance to cell contraction, providing passive mechanical excitation for myocardial tissue, and further promoting the maturation of cell morphology and function. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 is a schematic diagram of a method for preparing a cardiomyocyte signal detection platform provided in Example 1;

[0052] Figure 2 is a schematic diagram of the three-dimensional structure of the cardiomyocyte signal detection platform provided in Example 1;

[0053] Figure 3 is a morphological representation diagram of the metal microelectrode array in the myocardial cell signal detection platform provided in Example 1;

[0054] Figure 4 It is a front view of a first micro-beam structure flexible layer provided with a metal micro-electrode array in the cardiomyocyte signal detection platform provided in Example 1;

[0055] Figure 5 The device comprising the second microbeam structure flexible layer in the myocardial cell signal detection platform provided in Example 1;

[0056] Figure 6 is a front view of the second microbeam structure flexible layer in the myocardial cell signal detection platform provided in Example 1;

[0057] Figure 7 yes Figure 5 A magnified view of middle;

[0058] Figure 8 is a front view of the fiber scaffold-flexible micro-beam complex in the cardiomyocyte signal detection platform provided in Example 1;

[0059] Fig. 9 yes Figure 8 Cross-sectional view at B-B';

[0060] Fig.10 is a front view of the cardiomyocyte signal detection platform provided in Example 1;

[0061] Fig.11 yes Fig. 9 Cross-sectional view at C-C';

[0062] Fig.12 is an optical photograph of the cardiomyocyte signal detection platform provided in Example 1;

[0063] Fig.13 This is a partial optical photograph of the cardiomyocyte signal detection platform provided in Example 1, wherein the white filaments are fiber filaments, the black parts are microbeams and the second microbeam structure flexible layer covering them, and the large bright surface in the middle is the monitoring end of the metal microelectrode array;

[0064] Fig.14 The optical morphology micrograph and immunofluorescence staining graph of the cardiomyocyte signal detection platform and the planar PDMS MEA provided in Example 1 after being used to culture cardiomyocytes for 7 days respectively;

[0065] Fig.15 is the electrophysiological signal detected when the cardiomyocytes are cultured for multiple days in Example 1;

[0066] Fig.16 is a schematic structural diagram of a microelectrode array capable of realizing active mechanical excitation in Example 2;

[0067] Fig.17 It is a schematic diagram of the structure of the flexible curved beam microelectrode array of Example 3.

[0068] The reference numerals in the figure are: 1-first microbeam structure flexible layer, 2-metal microelectrode array, 21-detection end, 22-wire, 23-interface end, 3-second microbeam structure flexible layer, 4-ordered fiber support, 5-culture chamber, 51-cavity, 6-microbeam. DETAILED DESCRIPTION

[0069] The specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings and specific embodiments. The following examples and drawings are used to illustrate the present invention, but are not used to limit the scope of the present invention.

[0070] The present invention mentions that the microbeams extend in a first direction, the fiber filaments extend in a second direction, and the first direction is perpendicular to the second direction. In the preparation process, this feature is achieved by attaching a device containing a flexible layer of a second microbeam structure to a roller and making the microbeams parallel to the axial direction of the roller, rotating the roller brush, and arranging the fiber filaments ejected from the spinneret in the circumferential direction of the roller (perpendicular to the axial direction). However, in the actual preparation process, the formation direction of the fiber filaments does not completely coincide with the circumferential direction, so that an angle of less than 90° is formed between the fiber filaments and the microbeams. This structure should still be regarded as falling within the scope of protection of the present invention.

[0071] Example 1

[0072] like Figure 1-Figure 13 As shown, the cardiomyocyte signal detection platform of this embodiment includes two opposing culture chambers 5 and a fiber scaffold-flexible microbeam complex disposed between the two culture chambers 5 and irreversibly bonded to the culture chamber 5. The fiber scaffold-flexible microbeam complex is obtained by stacking a first microbeam structure flexible layer 1, a metal microelectrode array 2, a second microbeam structure flexible layer 3 and an ordered fiber scaffold 4 in sequence from bottom to top. Specifically, the preparation method of the cardiomyocyte signal detection platform is as follows Figure 1 The steps shown include:

[0073] (1) Preparation of the first flexible layer

[0074] The polydimethylsiloxane and the curing agent are mixed to obtain a polymer solution, which is then placed in a mold for curing, and the first flexible layer is obtained after demolding. In this embodiment, the curing agent is hydrogenated silicone oil, the amount of the curing agent added is XXwt%, the curing temperature is 85°C, and the curing time is 35 minutes.

[0075] (2) Preparing a metal microelectrode array 2 on the surface of the first flexible layer by magnetron sputtering

[0076] The first flexible layer is covered with a mask plate, exposing only the Figure 3 The position corresponding to the metal microelectrode array shown is then placed in a magnetron sputtering machine for sputtering. The sputtering power is 150 W and the sputtering time is 40 min. The mask is removed to obtain the first flexible layer provided with the metal microelectrode array 2.

[0077] (3) A plurality of micro-beams 6 are formed on the first flexible layer by laser cutting to obtain a first micro-beam structure flexible layer 1 provided with a metal micro-electrode array 2

[0078] The arrangement shape of each microbeam 6 on the first microbeam structure flexible layer 1 is designed to obtain a drawing of the first microbeam structure flexible layer, and then the drawing is introduced into the laser processing equipment and the first flexible layer provided with the metal microelectrode array 2 is laser cut. After the cutting is completed, anhydrous ethanol is used for ultrasonic cleaning for 15 minutes to remove the surface chips, and the following is obtained: Figure 4 The first micro-beam structure flexible layer 1 is shown to be provided with a metal micro-electrode array 2. In this embodiment, the laser processing device is an ultraviolet femtosecond laser. In other possible implementations, the laser processing device may be an ultraviolet picosecond laser or other existing laser processing devices.

[0079] (4) The second microbeam structure flexible layer 3 is prepared by electrostatic spraying on the surface of the first microbeam structure flexible layer 1 provided with the metal microelectrode array 2, and the detection end 21 and the interface end 23 of the metal microelectrode array are selectively exposed to obtain a device including the second microbeam structure flexible layer 3. The specific operation is as follows:

[0080] ① diluting the polymer solution in step (1) with n-hexane as a diluent so that it can then be introduced into an electrostatic spray device to form a spray;

[0081] ② Cover the surface of the first micro-beam structure flexible layer 1 provided with the metal micro-electrode array 2 with a mask plate, the mask plate covers the detection end 21 and the interface end 23 of the metal micro-electrode array 2 and exposes the Figure 6 The shape corresponding to the second micro-beam structure flexible layer 3 shown;

[0082] ③ A voltage of 10 kV was applied to the spray needle, the mask was grounded, the relative distance between the spray needle and the mask was 20 cm, the propulsion speed of the diluted polymer solution was 300 μL / h, and the spray time was 30 min;

[0083] ④ Place the sprayed device at 85℃ for 35 minutes, then remove the mask to obtain Figure 5 The device shown includes a second micro-beam structure flexible layer 3 .

[0084] (5) preparing an ordered fiber scaffold 4 on the second micro-beam structure flexible layer 3 by electrospinning to obtain a fiber scaffold-flexible micro-beam complex

[0085] ① Dissolve polycaprolactone in an organic solvent and stir until it is clear to obtain a fiber solution;

[0086] ② The device including the second micro-beam structure flexible layer 3 is attached to the roller, and then a fiber solution is sprayed on the second micro-beam structure flexible layer 3 by electrospinning to prepare an ordered fiber support 4, thereby obtaining a device integrated with the ordered fiber support 4;

[0087] ③ Take the device integrated with the ordered fiber support 4 off the drum, remove the excess fiber filaments, and obtain Figure 8 The fiber scaffold-flexible microbeam complex shown;

[0088] Wherein, the extension direction of the micro-beam 6 of the second micro-beam structure flexible layer 3 is the axial direction of the roller;

[0089] The operating conditions of electrospinning are as follows: the voltage applied to the spinneret is 10 kV, the drum is grounded, the relative distance between the drum and the spinneret is 20 cm, the propulsion speed of the fiber solution is 600 μL / h, the rotation speed of the drum is 1500 rpm, and the electrospinning time is 15 min.

[0090] (6) The upper and lower surfaces of the fiber scaffold-flexible microbeam complex are irreversibly bonded to the two culture chambers 5 to obtain a cardiomyocyte signal detection platform

[0091] The fiber scaffold-flexible micro-beam complex and the two culture chambers 5 were plasma treated for 75 seconds, and then positioned and attached and placed in a 45°C constant temperature box for 45 minutes to obtain the following Figure 10-13 The cardiomyocyte signaling detection platform is shown.

[0092] The structure of the cardiomyocyte signal detection platform of this embodiment is further described:

[0093] Figure 3 and Figure 4 The structure of the first micro-beam structure flexible layer 1 and the metal micro-electrode array 2 is shown. The first micro-beam structure flexible layer 1 is an insulating polydimethylsiloxane flexible substrate with a thickness of 350 μm. The first micro-beam structure flexible layer 1 is formed into a plurality of parallel linear micro-beams 6 by laser cutting in the middle thereof, and the extension direction of the micro-beams 6 is recorded as the first direction. Furthermore, the width of the micro-beam is 350 μm, and the distance between two micro-beams is 1 mm.

[0094] The first micro-beam structure flexible layer 1 is provided with a metal micro-electrode array 2. The metal micro-electrode array 2 is composed of a number of metal micro-electrodes, each of which includes a detection end 21 and an interface end 23, the detection end 21 and the interface end 23 are electrically connected, the detection end 21 array is arranged in the middle of the first micro-beam structure flexible layer 1, and the interface end 23 is arranged along the edge of the first micro-beam structure flexible layer 1. The detection end 21 is used to closely adhere to the cell to form a coupling capacitor to detect the electrophysiological signal of the cardiomyocyte, and the interface end 23 is used to connect with an external detection system to achieve the extraction of the electrophysiological signal. In this embodiment, the metal micro-electrode is a thin film with a thickness of 200nm obtained by platinum magnetron sputtering, the detection end 21 and the interface end 23 are respectively the two ends of the film, and the detection end 21 and the interface end 23 are connected by a wire 22. Further, the detection end 21 is rectangular, and its characteristic size is 50μm, the distance between the two detection ends 21 is 1500μm, and the interface end 23 is rectangular, and its characteristic size is 1.5mm.

[0095] The second micro-beam structure flexible layer 3 is disposed on the first micro-flexible layer 1 and the metal micro-electrode array 2 by electrostatic spraying. Figure 5 The device shown includes a second micro-beam structure flexible layer 3, and the second micro-beam structure flexible layer 3 formed by electrostatic spraying is uniform and dense, with a thickness of 15 μm, and its shape is as shown in the figure. Figure 5 and Figure 7 As shown, the second microbeam structure flexible layer 3 selectively exposes the detection end 21 and the interface end 23 and covers the wire 22 and most of the surface of the first microbeam structure flexible layer 1. The first microbeam structure flexible layer 1, the second microbeam structure flexible layer 3 and the metal microelectrode array 2 together constitute the flexible substrate and insulating layer of the myocardial cell signal detection platform.

[0096] The ordered fiber support 4 is arranged on the second micro-beam structure flexible layer 3 to form a Figure 8 and Fig. 9 In the fiber scaffold-flexible micro-beam complex shown, the ordered fiber scaffold 4 includes a plurality of directional fiber filaments, which can be freely attached and orderly grown by myocardial cells. The fiber density of the fiber filament scaffold 4 is 400 to 1000 fibers / mm, and the thickness of the ordered fiber scaffold 4 is 3 to 10 μm. The fiber filaments extend in the second direction, and the first direction and the second direction are perpendicular, providing a bionic microenvironment and passive mechanical excitation for myocardial cells.

[0097] The two culture chambers 5 are arranged opposite to each other and are irreversibly bonded to the upper and lower surfaces of the fiber scaffold-flexible micro-beam complex, respectively, to form a Figure 10-13 The cardiomyocyte signal detection platform shown. The culture chamber 5 has a cavity with a depth of 5 mm and a volume of 15 mm, and a growth space for cardiomyocytes is formed between two cavities 51. The cardiomyocyte signal detection platform can allow cardiomyocytes to grow in an orderly manner in vitro for a long time and detect the electrophysiological signals of cardiomyocytes.

[0098] Human induced pluripotent stem cell-derived cardiomyocytes were cultured at a rate of 0.5-1×104 cells / mm 2 The density of the cells was seeded on the engineered myocardial tissue microelectrode array and the planar PDMS microelectrode array of the integrated fiber scaffold and the flexible microbeam 6, respectively. The optical morphology and immunofluorescence staining of the cardiomyocytes during the culture process were shown in Figure 2. Fig.14 As shown in the figure, it can be seen that compared with the planar PDMS microelectrode array, the cardiomyocytes in the cardiomyocyte signal detection platform of this embodiment show an orderly growth state, which is closer to the morphology of mature cardiomyocytes in the human body. The electrophysiological signals detected on the 1st, 3rd and 10th days of culture are shown in FIG. Fig.15 As shown, the electrical signals of the cardiomyocytes cultured using the cardiomyocyte signal detection platform of this embodiment exhibit a larger amplitude, indicating its promoting effect on the maturation of cell function.

[0099] Example 2

[0100] The layout and preparation method of the cardiomyocyte signal detection platform of this embodiment are the same as those of Example 1, except that Fig.16 As shown, the cavity 51 of the culture chamber 5 is a pneumatic chamber, which can realize active mechanical excitation of the myocardial tissue.

[0101] Example 3

[0102] The layout and preparation method of the myocardial cell signal detection platform of this embodiment are the same as those of the embodiment 1, except that the micro-beams 6 of the first micro-beam structure flexible layer 1 are curved, specifically, a Fig.17 The serpentine beam shown can further improve the stretchability of the device and adapt to myocardial tissue contraction and active mechanical excitation.

[0103] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0104] The above are only preferred embodiments of the present invention, and therefore cannot be used to limit the scope of implementation of the present invention. That is, equivalent changes and modifications made according to the patent scope of the present invention and the contents of the specification should still fall within the scope of the present invention.

Claims

1. A cardiomyocyte signal detection platform, characterized in that: It includes a fiber support-flexible micro-beam complex, wherein the fiber support-flexible micro-beam complex is a first micro-beam structure flexible layer, a metal micro-electrode array, a second micro-beam structure flexible layer and an ordered fiber support stacked in sequence from bottom to top: The first micro-beam structure flexible layer is hollowed out to form a plurality of parallel micro-beams, and the micro-beams extend in a first direction; The metal microelectrode array comprises a plurality of metal microelectrodes, each of the metal microelectrodes having a detection end and an interface end, the detection end being electrically connected to the interface end, the detection end array of the plurality of metal microelectrodes being arranged on the first microbeam structure flexible layer, and the interface end being arranged along an edge of the first microbeam structure flexible layer; The second micro-beam structure flexible layer covers most of the surface of the metal micro-electrode array and exposes the detection end and the interface end; The ordered fiber support comprises a plurality of fiber filaments arranged in a direction, wherein the fiber filaments extend in a second direction, and the first direction is perpendicular to the second direction.

2. The myocardial cell signal detection platform according to claim 1, characterized in that: The density of the fiber filaments is 400-1000 filaments / mm, and the thickness of the ordered fiber support is 3-10 μm.

3. The myocardial cell signal detection platform according to claim 1 or 2, characterized in that: The method for preparing an ordered fiber scaffold on the second micro-beam structure flexible layer comprises the following steps: (a) dissolving polycaprolactone in an organic solvent and stirring until clear to obtain a fiber solution; (b) attaching a device including the second micro-beam structure flexible layer to a roller, and then spraying the fiber solution on the second micro-beam structure flexible layer by electrospinning to obtain a device integrated with an ordered fiber scaffold; (c) removing the device integrated with the ordered fiber support from the drum, removing excess fiber filaments, and obtaining the fiber support-flexible micro-beam complex; Wherein, the extension direction of the micro-beams of the second micro-beam structure flexible layer is the axial direction of the roller; The operating conditions of the electrospinning are: a voltage of 5 to 20 kV is applied to the spinneret, the roller is grounded, the relative distance between the roller and the spinneret is 10 to 30 cm, the propulsion speed of the fiber solution is 100 to 1000 μL / h, the rotation speed of the roller is 500 to 2000 rpm, and the electrospinning time is 5 to 20 min.

4. The myocardial cell signal detection platform according to claim 1, characterized in that: The micro beam is in a straight line, a broken line or a curved line.

5. The myocardial cell signal detection platform according to claim 1 or 4, characterized in that: The width of the micro-beam is 400-1000 μm, and the distance between two adjacent micro-beams is 1-1.5 mm.

6. The myocardial cell signal detection platform according to claim 1, characterized in that: The thickness of the first micro-beam structure flexible layer is 200-500 μm, and the thickness of the second micro-beam structure flexible layer is 10-20 μm.

7. The myocardial cell signal detection platform according to claim 1, characterized in that: The thickness of the metal microelectrode array is 100-500nm, the characteristic size of the detection end is 50-200μm, the distance between two adjacent detection ends is 400-2000μm, and the characteristic size of the interface end is 1-2mm.

8. The myocardial cell signal detection platform according to claim 1 or 7, characterized in that: The metal microelectrode is a thin film made of an inert noble metal, and the detection end and the interface end are two opposite ends of the thin film.

9. The myocardial cell signal detection platform according to claim 1, characterized in that: Also included are two culture chambers arranged opposite to each other; The culture chamber has a cavity with a depth of 2 to 5 mm and a volume of 5 to 15 mm, and the cavities of the two culture chambers are arranged opposite to each other; The fiber support-flexible micro-beam complex is arranged between the two culture cavities and is irreversibly bonded to the two culture cavities respectively.

10. The myocardial cell signal detection platform according to claim 9, characterized in that: The cavity is a pneumatic chamber.

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