Strain sensing device and method

Abstract

The invention provides a strain sensing device and method, the strain sensing device comprises a substrate, a thin film layer, a microelectrode array, a strain detection module and an encapsulation layer, the thin film layer is arranged on the substrate, a hole is formed in the middle of the substrate, two parallel openings are formed in the middle of the thin film layer, a separator is arranged between the two openings, and the microelectrode array is arranged in the hole. The two openings do not communicate with each other, and the two openings are each provided with a wing / wing type structure symmetrically distributed along the partition body; the microelectrode array comprises two groups of arrays which are respectively arranged on the outer sides of different openings; a strain detection module is arranged on the separator; and packaging layers are arranged on at least one part of the strain detection modules and the microelectrode arrays. According to the invention, the high-fidelity contraction waveform of myocardial cells can be captured in a larger frequency range.

Description

Technical Field

[0001] The present invention belongs to the field of strain sensing devices, and specifically relates to a strain sensing device and method, and in particular to a strain sensing device and method for weak stress measurement and analysis. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] Cardiovascular disease (CVD) has become a major threat to global health, and the parameters of the electrophysiological activity of cardiomyocytes, such as amplitude, frequency, rhythm, and QT interval, have been widely used in CVD research and drug testing. Although existing studies have proposed parameters of contractility (such as amplitude and beat frequency), compared with electrophysiological activity parameters, these contractility parameters are not sufficient to construct complete mechanical activity analysis parameters for clinical diagnosis of diseases. This is mainly attributed to the lack of sufficient bandwidth of the sensor, which makes it impossible to detect rich contraction waveforms containing multi-frequency components (>1.48Hz).

[0004] In recent years, flexible films with integrated piezoresistive sensors have been used to measure the contractility of cardiomyocytes by recording the resistance changes of the sensors. There are two main structures of flexible films with integrated piezoresistive sensors. One is a cantilever device with one end fixed. However, the cantilever used to measure the contraction of cardiomyocytes is usually made of tough materials (such as polydimethylsiloxane), which dissipates a lot of mechanical energy (caused by the relative movement between the internal molecular structure and molecular chains) when deflected (induced by cardiomyocytes), resulting in a decrease in bandwidth. The other structure is a flexible membrane device with a completely fixed periphery (such as a cell drum). The low bandwidth of this device (1.48±0.14Hz) is attributed to its high damping coefficient (55.42±3.73) caused by the complete fixation of its structure and the gravity of the culture medium itself.

[0005] Therefore, there is an urgent need for a high-bandwidth (low damping coefficient) strain sensor to capture the waveform of myocardial cell contraction. High-frequency information can reflect detailed and subtle waveform characteristics to establish an index system for contractility, providing biomechanical information for comprehensive evaluation of myocardial contractile behavior in clinical diagnosis, treatment, and drug screening. Summary of the invention

[0006] In order to solve the above problems, the present invention proposes a strain sensing device and method.

[0007] According to some embodiments, the present invention adopts the following technical solutions:

[0008] A strain sensing device comprises a substrate, a thin film layer, a microelectrode array, a strain detection module and a packaging layer, wherein:

[0009] A film layer is arranged on the substrate, a hole is arranged in the middle of the substrate, two openings are arranged side by side in the middle of the film layer, a separator is arranged between the two openings so that the two openings are not connected, and a wing / airfoil-shaped structure symmetrically distributed along the separator is arranged at each of the two openings;

[0010] The microelectrode array includes two groups of arrays, which are respectively arranged outside different openings;

[0011] The separator is provided with a strain detection module;

[0012] An encapsulation layer is disposed on at least a portion of the strain detection module and the microelectrode array.

[0013] The above technical solution sets a butterfly-like structure (composed of a separator and a wing / airfoil structure) in the middle of the film layer, and sets a strain detection module / strain sensor thereon. The two ends of the separator are fixed, a part of the wing / airfoil structure is connected to the separator, and the other part is unfolded and suspended. Under the same strain, the butterfly-shaped sensor can produce a larger strain, and combined with the microchannel, it can effectively improve the sensitivity of myocardial cell contraction detection.

[0014] As an optional implementation, the substrate is made of polymethyl methacrylate (PMMA).

[0015] As an optional implementation, the film layer is a PMMA film.

[0016] As an optional embodiment, the separator and the wing / airfoil structure are both PMMA films.

[0017] As an optional embodiment, the wing / airfoil-shaped structure is provided with a plurality of microchannels arranged side by side along a set direction, and the microchannels are used to self-assemble into anisotropic myocardial tissue when the strain sensing device is used to detect the contraction of myocardial cells.

[0018] As an optional embodiment, the set direction is perpendicular to the distribution direction of the separator, or is consistent with the extension direction of the wing / airfoil structure.

[0019] As an optional embodiment, the opening is rectangular, and the two openings have the same size.

[0020] As an optional embodiment, one end of the wing / airfoil structure is connected to one side of the separator, and the other end does not contact the sides of the corresponding opening.

[0021] As an optional embodiment, each group of the microelectrode array includes a plurality of microelectrodes arranged in parallel, for detecting the field potential of myocardial cells.

[0022] As an optional implementation, the strain detection module is arranged along the separator, and a protrusion is provided in the middle, and the protrusion is provided on one of the wing / airfoil structures.

[0023] The method for preparing the strain sensor device comprises the following steps:

[0024] Bonding substrate on glass slide;

[0025] Spin-coat PMMA solution on another glass slide to make a thin film layer;

[0026] Laser cutting of fin / airfoil structures in the film layer;

[0027] 3D printing to prepare strain detection modules and microelectrode arrays on the thin film layer;

[0028] bonding a film layer to a substrate;

[0029] The encapsulation layer is bonded on the microelectrode array and the strain detection module using an acetone-PMMA solution;

[0030] The resulting material is cured to obtain a final strain sensing device.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] The present invention provides a strain sensing device with low damping coefficient and high bandwidth based on a butterfly-like structure, which can capture high-fidelity contraction waveforms of myocardial cells within a larger frequency range. After experimental simulation, it can detect frequency components that traditional sensing devices cannot detect.

[0033] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0035] Figure 1 is a schematic structural diagram of a strain sensing device according to an embodiment;

[0036] Figure 2 is a schematic diagram of a strain sensing device according to an embodiment;

[0037] Figure 3 is a schematic diagram of a maskless, room temperature rapid preparation process of a substrate, a strain sensor and a microelectrode according to an embodiment;

[0038] Figure 4Schematic diagram of high-fidelity measurement and analysis of cardiomyocyte contractility according to an embodiment. DETAILED DESCRIPTION

[0039] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0040] It should be noted that the following detailed descriptions are all illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0041] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0042] In the absence of conflict, the embodiments in this application and the features in the embodiments may be combined with each other.

[0043] Embodiment 1

[0044] A strain sensing device is described in detail using the detection of myocardial cell contraction as an application scenario. Of course, this does not mean that the solution of the present invention can only be used in this scenario. Figure 1 As shown, it includes a substrate, a thin film layer, a microelectrode array, a strain detection module and a packaging layer, wherein:

[0045] A thin film layer is arranged on the substrate, a hole is arranged in the middle of the substrate, two openings are arranged side by side in the middle of the thin film layer, a separator is arranged between the two openings so that the two openings are not connected, and a wing / airfoil structure (the main body is shaped like a butterfly, inspired by the butterfly, the butterfly-shaped sensor can produce a larger strain under the same strain) is arranged at the two openings respectively, and the wing / airfoil structure is driven to deflect when the myocardial tissue contracts, and the strain detection module generates a corresponding resistance signal;

[0046] The microelectrode array includes two groups of arrays, which are respectively arranged outside different openings and are mainly used to detect the field potential of myocardial cells;

[0047] The separator is provided with a strain detection module (or called a strain sensor, the same below), which is mainly used to detect the contractile force of myocardial cells;

[0048] At least a portion of the strain detection module and the microelectrode array is provided with an encapsulation layer, and the encapsulation layer can reduce noise in the signal;

[0049] The wing / airfoil-shaped structure is provided with a plurality of microchannels arranged side by side in a set direction. The microchannels are used for self-assembly of myocardial cells into anisotropic myocardial tissue when the strain sensing device is used to detect the contraction of myocardial cells.

[0050] In this embodiment, the substrate is made of polymethyl methacrylate (PMMA).

[0051] In this embodiment, the film layer is a PMMA film.

[0052] In this embodiment, the separator and the wing / airfoil-shaped structure are both PMMA films.

[0053] In this embodiment, the setting direction of the microchannel is perpendicular to the distribution direction of the separator, or consistent with the extension direction of the wing / airfoil structure.

[0054] In this embodiment, the openings are rectangular, and the two openings have the same size.

[0055] In this embodiment, one end of the wing / airfoil structure is connected to one side of the separator, and the other end does not contact the sides of the corresponding opening.

[0056] In this embodiment, each group of the microelectrode array includes a plurality of microelectrodes (four in this embodiment) arranged in parallel, for detecting the field potential of myocardial cells.

[0057] In this embodiment, the strain detection module is a CNT-piezoresistive strain sensor, which is arranged along the separator and has a protrusion in the middle, and the protrusion is arranged on one of the wing / airfoil structures.

[0058] In this embodiment, the substrate is disposed on a glass slide and further includes a circular culture well.

[0059] When using, Figure 2 As shown in (a), multiple (six in the figure) strain sensing devices can be used for simultaneous detection and analysis, each device containing eight microelectrodes and a strain sensor. Figure 2 (b) and (c) show that the device provided in this embodiment, the working principle of the strain sensing device inspired by butterfly wings (hereinafter also referred to as the bionic butterfly sensing device), is that the contraction of the anisotropic engineered heart tissue causes the butterfly wing / airfoil structure to deflect, thereby stretching and generating soft strain.

[0060] like Figure 2 (d) and (e) are SEM images of the microstructure of the wing surface of the bionic butterfly sensor device. The channel width of this embodiment is at the micron level, which is used to self-assemble into anisotropic myocardial tissue.

[0061] like Figure 2 As shown in (f) and (h), the strain and displacement generated by applying the same stress on the surface of three typical structures: the bionic butterfly sensor device (left), fixed at one end (middle), and fixed all around (right). The black line represents the fixed constraint, combined with Figure 2 (g) It can be seen that compared with the one-end fixed and four-sided fixed, the strain of the bionic butterfly sensor device is 3.25 times (3.80×10 -4 % and 1.17×10 -4 %) and 17.58 times (4.15×10 -4 % and 2.36×10 -5 %).like Figure 2 (i) shows the magnetic platform for characterizing the sensing device. Under a constant voltage, the magnetic field generated by the copper coil induces the magnetic film to drive the strain sensing device to deflect, which can be observed by a CCD camera.

[0062] like Figure 2 As shown in (j), the normalized ΔR / R0 of the bionic butterfly sensor device, one-end fixed, and four-sided fixed sensors when strain is generated (frequency is 0-25Hz) under a fixed electromagnetic field (driven by 30V voltage). As the deflection frequency increases, the ΔR / R0 of the bionic butterfly sensor device decreases slowly, while the ΔR / R0 of the other two sensors decreases rapidly. Figure 2 (k) shows the bandwidth and corresponding damping coefficient of the bionic butterfly sensor device, the sensor with one end fixed and the sensor with all four sides fixed. As the damping coefficient increases from 0.84±0.13 to 55.42±3.73, the bandwidth decreases from 22.85±1.07Hz to 1.48±0.14Hz.

[0063] In this embodiment, the strain sensor uses a CNT-piezoresistive strain sensor, and according to the above simulation results, the micro-grooves on the surface of the butterfly wing are conducive to the formation of anisotropic tissues in the same way as the heart in vivo by myocardial cells. The finite element analysis results show that the micro-grooves made using the photolithography process can increase the strain of the sensor by about 116.71%; the contraction of the myocardial tissue causes the base of the simulated butterfly wing to deflect, and the CNTs in the conductive network of the composite material are disconnected and contacted, thereby causing a relative change in resistance.

[0064] Conventional sensors (cantilevered (OEF) and all-around fixed (AEF)) have low bandwidth (1.48±0.14Hz). When capturing the contractile behavior of cardiomyocytes, waveform distortion occurs. This is mainly attributed to the excessive dissipation of mechanical energy caused by the large relative motion between the molecular chains inside these sensors and the high damping coefficient caused by different Dirichlet boundary conditions.

[0065] To solve these problems, we optimized the strain amplitude, eigenfrequency and damping coefficient related to bandwidth based on the butterfly flapping motion mechanism and designed a bionic butterfly sensor (BBF). The formula for the lift generated by the butterfly flapping is as follows:

[0066]

[0067] where ρ is the fluid density, A is the cross-sectional area of ​​the airfoil, v is the velocity of a point within the airfoil, r is the distance from the origin of an arbitrary coordinate system moving with the freestream, ω is the vorticity, R is the area of ​​the region of interest containing all vorticity elements, and S is the circumference of the airfoil cross section.

[0068] Under the same stress, the maximum strain of the bionic butterfly sensor device is 3.25 times that of the cantilever type (3.80×10 -4 % vs.1.17×10 -5 %) and 17.58 times (3.80×10 -4 % vs.2.36×10 -5 %), which suggests that the bionic butterfly sensor device can improve the sensitivity of myocardial cell contraction detection.

[0069] High bandwidth is important for capturing undistorted cardiomyocyte contraction waveforms.

[0070] In a second-order sensor system, the bandwidth is the frequency value corresponding to the output amplitude being reduced to 1 / √2 times. The amplitude-frequency characteristic formula is:

[0071]

[0072] Where A(ω) is the output amplitude of the sensor (ΔR / R0), ω is the frequency of the input signal, n is the eigenfrequency of the sensor, and ξ is the damping coefficient of the sensor.

[0073] The eigenfrequencies of BBF, OEF, and AEF were calculated by the D'Alembert equation, which were 23.68 Hz, 33.96 Hz, and 400.48 Hz, respectively. In order to solve the ξ of BBF, OEF, and AEF in formula (1), magnetic nanoparticles were uniformly embedded on the sensor surface based on the principle that the electromagnetic field gradient force controls the movement of the magnetic film, and the output amplitude of the sensor within 0-25 Hz was evaluated under a fixed electromagnetic field. With the increase of the driving frequency, the normalized ΔR / R0 of BBF, OEF, and AEF decreased from 1 to 0.68±0.07, 0.29±0.09, and 0.10±0.09, respectively, indicating that the response of BBF, OEF, and AEF to high frequencies gradually decreased. The calculated bandwidths are 22.85±1.07Hz, 4.22±0.39Hz, and 1.48±0.14Hz, and the corresponding damping coefficients are 0.84±0.13, 3.34±0.24, and 55.42±3.73, respectively.

[0074] In addition, in order to achieve high-fidelity response of the high-bandwidth sensor to weak stress (1-15 kPa) of layered myocardial tissue, the substrate thickness is reduced by adjusting the viscosity and spin coating speed of the PMMA-acetone solution in the substrate preparation process, such as Figure 3 (a) and (b) are shown. PMMA-acetone mixed solutions with different volume ratios are used to make PMMA films. Their viscosities are 2068.33±10.41mPa·s, 308.33±2.52mPa·s, 115.67±1.53mPa·s, 17.23±2.11mPa·s and 14.57±0.15mPa·s respectively. When the volume ratio of PMMA:acetone is 1:4, the liquid hardly flows, while when the volume ratio is 1:8, it flows evenly. At a spin coating speed of 1000rpm, when the solution viscosity changes from 2068.33±10.41mPa·s (V PMMA :V acetone =1:4) decreased to 115.67±1.53mPa·s(V PMMA :V acetone =1:6), the average thickness of the film decreased from 65.88±5.08μm to 23.57±4.86μm. At the same speed, when the viscosity was further reduced to 17.23±2.11mPa·s(V PMMA :V acetone =1:7), cracks appear on the film surface and a complete structure cannot be formed.

[0075] like Figure 3As shown in (b) and (c), when the viscosity is fixed (115.67±1.53mPa·s), the spin coating speed increases from 1000rpm to 9000rpm, the average thickness decreases from 23.57±4.86μm to 5.08±0.67μm, and the minimum thickness is 4.43μm.

[0076] Conformal printing of sensitive elements is critical for the consistency of high-bandwidth sensors, ensuring uniform and high-fidelity electrical responses during cardiomyocyte contraction. The viscosity of the conductive ink decreases with increasing shear rate, known as shear thinning behavior, at a fixed 10wt.% CNT. However, the low apparent viscosity and low yield stress of the ink cause the ink to spread on the substrate and produce cracks. Quantitative analysis results show that the length and number of cracks under the same optical field of view are higher than 0.57±0.23μm (maximum 252.60±49.01μm) and 14.67±2.52 (maximum 47±5.57), respectively. In contrast, when the volume ratio is higher than 1:4, nozzle clogging is attributed to the viscosity exceeding 51.59Pa·s. The experimental results found that the ink with a volume ratio of 1:4 provided the best 3D printing performance (no cracks, no extension).

[0077] To avoid signal distortion caused by delamination between the strain sensor, microelectrode, and substrate, we repolymerized the PMMA chains via a solution-curing process.

[0078] The microgrooves of this embodiment promote the self-assembly of cardiomyocytes into anisotropic tissues similar to the heart in vivo. The results show that cardiomyocytes cultured on microgrooves made by photolithography grow along the direction of the grooves, while the growth direction of cardiomyocytes on the flat surface is random. In order to quantitatively evaluate the effect of microgrooves on cardiomyocyte growth, we measured the sarcomere orientation angle, sarcomere length and nuclear aspect ratio of cardiomyocytes. The growth direction of 75% of cardiomyocytes on the microgrooves is consistent with the pattern (±20°), while the growth direction of cardiomyocytes on the flat surface is random. The average sarcomere length of cardiomyocytes on the microgrooves is 1.298 times that of the flat surface (1.50±0.14μm vs.1.16±0.28μm). The nuclear aspect ratios of cardiomyocytes are 1.67±0.33 and 1.35±0.18, respectively.

[0079] To prove that the bionic butterfly sensor can measure the contraction waveform with high fidelity, we cultured cardiomyocytes on the bionic butterfly sensor, cantilever and four-sided fixed sensors for 10 days. The reliability of the contraction waveform measured by the bionic butterfly sensor was verified by combining field potential, representative ΔR / R0 trajectory and field potential, such as Figure 4 As shown in Figure 2, cardiomyocyte contraction can cause sensor deflection. The bionic butterfly sensor device can measure the synchronous contraction of cardiomyocytes on the second day, while other sensors can only measure the synchronous contraction of cardiomyocytes on the third day.

[0080] This is attributed to the fact that the bionic butterfly sensor with a low damping coefficient can produce a larger strain under the same contractile force, which reflects the measurement advantage of the contractile force in the early development of cardiomyocytes. The contractile force measured by the three types of sensors reached the maximum value on the 6th day, and then gradually decreased with the aging of cardiomyocytes. The contractile force amplitudes of the three types of sensors on the 6th day were 1.90×10 -4 ±2.25×10 -5 , 1.17×10 -4 ±1.38×10 -5 and 9.69×10 -5 ±1.01×10 -5 This is because the high-bandwidth bionic butterfly sensor can reflect the myocardial contraction behavior with high fidelity. Field potential is used as the gold standard to verify the reliability of the bionic butterfly sensor. The measured contraction waveform and field potential show consistent change trends in frequency and amplitude.

[0081] Time-frequency domain methods are commonly used to analyze frequency components, frequency ranges, and frequency intensities. The fidelity of the contraction waveforms measured by the three types of sensors on day 6 was characterized using the time-frequency domain method. Compared with traditional sensors, the bionic butterfly sensor device is able to measure more frequency components. This can enhance the amplitude of the contraction force collected; and enrich the collected waveforms, which is likely related to the physiological Ca2+ at the beginning of myocardial cell diastole. 2+ -ATPase pump or Na + / Ca 2+ The exchanger caused a transient decrease in calcium ion concentration, which corresponded to the contractile pulsation frequency measured by the three types of sensors, which were 0.80±0.10 Hz, 0.79±0.13 Hz, and 0.70±0.09 Hz, respectively, which was consistent with the frequency of the field potential.

[0082] To demonstrate the potential application of the platform integrating the biomimetic butterfly sensing device and microelectrode array and the established contractility analysis parameters in drug screening, three representative cardiac drugs were tested.

[0083] Verapamil is a LTCC blocker known to inhibit Ca 2+ After adding different concentrations of verapamil (0.1nM, 1nM, 10nM, 100nM, 1μM), the contractile force (ΔR / R0) increased from 2.01×10 -4 ±0.08×10 -4 Reduced to 6.29×10 -5 ±0.06×10 -5, the field potential amplitude decreased from 21.23±0.59μV to 17.83±0.68μV. Verapamil reduced the field potential amplitude and contraction force amplitude of cardiomyocytes in a concentration-dependent manner, and the secondary peak in diastole gradually disappeared. This is attributed to the reduction of calcium ion influx and calcium-induced calcium release after the LTCC channel was blocked. However, traditional contraction force sensors cannot detect secondary peaks. After treatment with 10nM verapamil, the contraction force beat frequency decreased from 0.74Hz to 0.54Hz, and the main frequency intensity of contraction force decreased from 8.98×10 -3 Reduced to 5.32×10 -3 , which is because the repolarization of myocardial cells is prolonged. Based on the dose-response curves of the three drugs, the IC values ​​of normalized contractility and beat frequency were calculated. 50 or EC 50 They are 1.89×10 -8 M, 1.80×10 -8 M, 1.35×10 -8 M, 2.74×10 -9 M, 1.09×10 -8 M.IC 50 Value and EC 50 The values ​​were close to the data previously reported for neonatal rat cardiomyocyte tissue.

[0084] These results confirm that the bionic butterfly sensor device can detect the dynamic changes of cardiomyocyte contractility analysis indicators and diastolic peaks induced by different drug doses, which cannot be observed in existing contractility and electrophysiological studies.

[0085] Embodiment 2

[0086] The method for preparing the strain sensor device comprises the following steps:

[0087] Bonding substrate on glass slide;

[0088] Spin-coat PMMA solution on another glass slide to make a thin film layer;

[0089] Laser cutting of fin / airfoil structures in the film layer;

[0090] 3D printing to prepare strain detection modules and microelectrode arrays on the thin film layer;

[0091] bonding a film layer to a substrate;

[0092] The encapsulation layer is bonded on the microelectrode array and the strain detection module using an acetone-PMMA solution;

[0093] The resulting material is cured to obtain a final strain sensing device.

[0094] The above description is only a preferred embodiment of the present invention and is 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 by those skilled in the art within the spirit and principle of the present invention without creative labor shall be included in the protection scope of the present invention.

Claims

1. A strain sensing device, characterized in that: It includes a substrate, a thin film layer, a microelectrode array, a strain detection module and a packaging layer, wherein: A film layer is arranged on the substrate, a hole is arranged in the middle of the substrate, two openings are arranged side by side in the middle of the film layer, a separator is arranged between the two openings so that the two openings are not connected, and a wing / airfoil-shaped structure symmetrically distributed along the separator is arranged at each of the two openings; The microelectrode array includes two groups of arrays, which are respectively arranged on the outsides of different openings; The separator is provided with a strain detection module; An encapsulation layer is disposed on at least a portion of the strain detection module and the microelectrode array.

2. A strain sensing device as claimed in claim 1, characterized in that: The substrate is made of polymethyl methacrylate (PMMA).

3. A strain sensing device as claimed in claim 1, characterized in that: The film layer is a PMMA film; The separator and the wing / airfoil structure are both PMMA films.

4. A strain sensing device as claimed in claim 1, characterized in that: The wing / airfoil-shaped structure is provided with a plurality of microchannels arranged side by side in a set direction. The microchannels are used to self-assemble into anisotropic myocardial tissue when the strain sensing device is used to detect the contraction of myocardial cells.

5. A strain sensing device as claimed in claim 1, characterized in that: The set direction is a direction perpendicular to the distribution direction of the separator, or a direction consistent with the extension direction of the wing / airfoil structure.

6. A strain sensing device as claimed in claim 1, characterized in that: The openings are rectangular, and the two openings have the same size.

7. A strain sensing device as claimed in claim 1, characterized in that: One end of the wing / airfoil structure is connected to one side of the separator, and the other end does not contact the sides of the corresponding opening.

8. A strain sensing device as claimed in claim 1, characterized in that: Each group of the microelectrode arrays includes a plurality of microelectrodes arranged in parallel.

9. A strain sensing device as claimed in claim 1, characterized in that: The strain detection module is arranged along the separator, and a protrusion is arranged in the middle, and the protrusion is arranged on one of the wing / airfoil structures.

10. The method for preparing a strain sensor device according to any one of claims 1 to 9, characterized in that: The following steps are involved: Bonding substrate on glass slide; Spin-coat PMMA solution on another glass slide to make a thin film layer; Laser cutting of fin / airfoil structures in the film layer; 3D printing to prepare strain detection modules and microelectrode arrays on the thin film layer; bonding a film layer to a substrate; The encapsulation layer is bonded on the microelectrode array and the strain detection module using an acetone-PMMA solution; The resulting material is cured to obtain a final strain sensing device.

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