Artificial intestinal villus bionic peristalsis experimental model driven by variable magnetic field

Abstract

The invention discloses an artificial intestinal villus bionic peristalsis experimental model driven by a variable magnetic field, and belongs to the technical field of bionic in-vitro models. The model comprises a flexible substrate and an artificial magnetic intestinal villus array constructed on the surface of the flexible substrate. A plurality of annular electrified coils are arranged, the coils sequentially and continuously sweep over the outer wall of the long cylindrical small intestine model in a surrounding mode, then space-time changing magnetic field distribution is formed, the villus array is driven to generate periodic collaborative movement with phase differences, the directional wriggling function of the digestive tract is simulated, and the conveying and mixing process of food and medicine in the digestive tract is reproduced. By adjusting the current intensity, the frequency and the operation speed of the coil, accurate control over the direction, the amplitude and the frequency of villus movement can be achieved, and therefore the intestinal tract dynamic characteristics under different physiological or pathological conditions are simulated. The model disclosed by the invention can be matched with a fluid channel, a permeable membrane or cell culture for use, and is used for in-vitro research on a drug release and transportation mechanism, food digestion kinetics, an intestinal disease mechanism and evaluation of related medical preparations and instruments.

Description

Technical Field

[0001] This invention belongs to the field of biomimetic in vitro model technology, specifically relating to an artificial small intestinal villi biomimetic peristalsis experimental model driven by a changing magnetic field. Background Technology

[0002] The intestines are one of the most important digestive and absorptive organs in the human body. Their main function is to break down food into absorbable nutrients, while also playing crucial roles as a barrier and in immune regulation. In intestinal physiology, the villi and peristalsis of the intestinal wall play a central role: the villi, through periodic oscillation and expansion, increase the contact area within the intestinal lumen, significantly promoting the absorption of nutrients and drugs; while peristalsis, through coordinated propulsive waves, facilitates the transport and mixing of contents, thus ensuring efficient transport and absorption of substances.

[0003] In recent years, the incidence of intestinal-related diseases has been on the rise, including inflammatory bowel disease, irritable bowel syndrome, intestinal motility disorders, malabsorption syndrome, and various drug-induced gastrointestinal injuries. One common characteristic of these intestinal diseases is abnormal intestinal motility, such as disordered peristaltic rhythms, decreased transit function, and impaired villus morphology and function. Therefore, a deeper understanding of the mechanisms of intestinal peristalsis and villus movement in healthy and disease states is of great significance for disease mechanism research, drug development, and improvements in treatment methods.

[0004] Currently, the main methods for studying intestinal function and disease mechanisms include animal experiments and in vitro static models. Animal models can reflect the overall physiological environment well, but they exhibit significant cross-species differences and face challenges such as ethical restrictions, high costs, and poor reproducibility. On the other hand, traditional in vitro models are mostly static cell cultures or one-way perfusion systems. While they can partially simulate the dissolution and absorption of nutrients or drugs in the intestinal lumen, they lack peristaltic function and villus structure, making it difficult to reproduce the complex dynamic environment of the intestine. This often leads to discrepancies between in vitro drug evaluation results and actual clinical absorption, limiting their application value in drug screening, food digestion research, and disease model construction.

[0005] In recent years, some studies have attempted to incorporate biomimetic engineering techniques, such as intestinal chips and biomimetic cavity fluid systems. These microfluidic systems have improved fluid dynamics to some extent and can be used for epithelial cell co-culture, but most are still limited to planar flow channel structures and lack effective simulation of the three-dimensional morphology and active peristaltic characteristics of small intestinal villi. Therefore, how to simultaneously reproduce the structural features and peristaltic movements of small intestinal villus arrays in an in vitro experimental platform has become a pressing technical challenge. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing in vitro intestinal models, which lack peristaltic function and struggle to reproduce the structure and dynamics of the small intestinal villi. This invention proposes a biomimetic in vitro intestinal experimental model driven by a continuously and stably changing magnetic field, featuring an artificial magnetic small intestinal villus array with directional peristalsis. This invention constructs a magnetic small intestinal villus array on a flexible substrate and places multiple ring-shaped energized coils connected in a track-like manner outside the model. The spatial-temporal changing magnetic field generated by the continuous movement of the coils along the outer wall of the long, cylindrical small intestine model drives the villus array to produce periodic, coordinated oscillations with a phase difference, thereby achieving a biomimetic simulation of small intestinal peristaltic waves.

[0007] The objective of this invention is achieved through the following technical solution:

[0008] An experimental model of artificial small intestinal villi peristalsis driven by a changing magnetic field includes:

[0009] The camera and fixing device 1 is used to perform real-time imaging and recording of the inside of the intestinal model 2, and at the same time provide mechanical support for the artificial small intestinal villi biomimetic peristalsis experimental model to ensure stability during the observation process.

[0010] Intestinal model 2 includes a flexible long cylindrical structure 2-1, on which a magnetic villus array 2-2 is uniformly distributed on the inner wall surface. The magnetic villus array 2-2 is a soft artificial small intestinal villus array containing magnetic particles, used to simulate the three-dimensional structural morphology of small intestinal villi and their movement characteristics under physiological conditions.

[0011] The motor track and ring-shaped energized coil assembly 3 includes a drive motor, a ring-shaped energized coil 3-1, a middle beam structure 3-2, and a track assembly 3-3. The drive motor drives the track assembly 3-3 to move cyclically, causing the ring-shaped energized coil 3-1 to move continuously along the outer wall of the intestinal model 2. By controlling the energization, a time-varying spatial magnetic field is generated, thereby driving the magnetic villus array 2-2 inside the intestinal model 2 to produce coordinated oscillation with a phase difference, realizing the biomimetic simulation of small intestinal peristalsis waves.

[0012] Furthermore, the camera and fixing device 1 includes a camera 1-1 and a fixing frame 1-2; the camera 1-1 is cubic in shape, preferably with an external size of 10 cm × 10 cm, and integrates an image sensor chip, an optical lens assembly, a control circuit and a data transmission interface; the front end of the lens of the camera 1-1 is provided with a fixing frame 1-2 (preferably with a length of 4 cm), which is fixed to the outer wall of the intestinal model 2.

[0013] Furthermore, the fixing frame 1-2 includes a support frame and an adjustable angle buckle. The support frame connects the front end of the lens and the adjustable angle buckle, and is made of a lightweight and high-strength material (such as aluminum alloy). The adjustable angle buckle can wrap around and clamp onto the outer wall of the intestinal model 2. The fixing frame 1-2 can realize the fine adjustment and locking of the camera 1-1 in the radial and axial positions, so that the lens is aligned with the center of the observation area of ​​the intestinal model 2.

[0014] Furthermore, the camera 1-1 is equipped with a shock-absorbing pad to reduce the interference of mechanical vibration generated by the motor track operation on image acquisition. The camera 1-1 is connected to the control and data acquisition unit via wired or wireless means, enabling real-time image display, storage, and subsequent processing and analysis, and is used to monitor the motion state and fluid transport process of the magnetic villus array inside the intestinal model 2.

[0015] Furthermore, the flexible cylindrical structure 2-1 is formed by winding and sealing a pre-prepared flat polydimethylsiloxane (PDMS) film, and is in the shape of a hollow cylinder. Its size is adapted to the size of the small intestine. Preferably, the length is 20 cm, the inner diameter is 3 cm, the outer diameter is 4 cm, and the wall thickness is 1 cm.

[0016] Furthermore, each magnetic intestinal villus in the magnetic villous array 2-2 is a soft, cylindrical microstructure, preferably with a diameter of 0.5 mm and a length of 2 mm, and its matrix material is uniformly mixed with superparamagnetic microparticles. The magnetic villous array 2-2 is uniformly arranged along the circumferential and axial directions of the inner wall, preferably with a spacing of approximately 2.27 mm between the tops of adjacent villus, and 36 villous structures are uniformly arranged around the circumference; along the center direction of the circular tube, the distance between adjacent cilia is approximately 3 mm.

[0017] Furthermore, the motor track and the ring-shaped energized coil assembly 3 serve as the magnetic field driving module of the artificial small intestinal villi biomimetic peristalsis experimental model, which is used to generate a continuously and stably changing spatial-temporal magnetic field outside the intestinal model 2, thereby driving the magnetic villi array 2-2 on the inner wall of the intestinal model 2 to generate periodic coordinated time-varying oscillations.

[0018] Furthermore, the annular energized coil 3-1 is made of conductive metal wire and can generate a stable annular magnetic field after being energized. The individual coil has a clamp-like structure, preferably with an inner diameter of approximately 6 cm and an outer diameter of approximately 8 cm. A 30° notch is provided on the coil ring to allow it to pass over the flexible, elongated cylindrical structure 2-1 of the intestinal model 2 during assembly and operation, enabling the annular energized coil 3-1 to pass over and encircle the outer wall of the intestinal model 2 without interference. The annular energized coil 3-1 has wire interfaces at both ends, which can be connected to a control power supply. The magnetic field strength and phase can be controlled by adjusting the current magnitude and the on / off sequence.

[0019] Furthermore, the annular energized coil 3-1 and the track assembly 3-3 are connected via an intermediate beam structure 3-2. Each intermediate beam is 16 cm long, with one end fixedly connected to the outside of the coil and the other end fixedly connected to the track plate. The intermediate beams are made of high-strength, lightweight materials (aluminum alloy or carbon fiber reinforced plastic) to ensure operational stability while reducing the system's inertial load. Multiple coils can be installed in the entire magnetic drive system, each coil being fixed to the corresponding track plate via an intermediate beam, enabling track-like cyclic operation along the outer wall of the intestinal model under the drive of the track movement.

[0020] Furthermore, the track assembly 3-3 is formed by connecting several track plates end to end in a hinged manner to form a closed loop transmission chain, which is driven by a motor to perform cyclic motion.

[0021] Furthermore, the center distance d between two adjacent track plates is set to a predetermined value, which corresponds to the target wavelength λ of the propulsive metachronal wave generated by the changing magnetic field, i.e.

[0022]

[0023] When the electromagnetic coil array moves in a cycle, the magnetic field it generates can act on the target object sequentially with a phase difference, thereby forming a propulsive creeping wave in space. The preferred center-to-center spacing d is approximately 8 cm. The specific principle for selecting the center-to-center spacing is as follows:

[0024] 1. Lower limit constraint: The spacing d must be greater than a minimum threshold d. min This minimum threshold is determined by two factors: one is the physical thickness t of the electromagnetic coil itself. coil Secondly, the minimum safety gap g required to avoid interference between the magnetic fields of adjacent coils. min .

[0025] 2. Upper limit constraint: The spacing d must be less than a maximum threshold d. max If the spacing is too large, the resulting wave will become discontinuous in space, failing to form an effective time-separated wave, thus losing its propulsive creeping driving effect.

[0026] The present invention does not impose fixed limitations on the length of the track and the number of the installed annular energized coils. These can be flexibly increased or decreased according to experimental requirements. As long as the coil units are set at equidistant intervals d along the track running path, so that the spatial phase difference distribution can be maintained during the coil's cyclic movement, a continuous and stable biomimetic peristaltic driving effect can be achieved.

[0027] This invention provides at least the following beneficial effects:

[0028] Highly realistic peristaltic reproduction capability: This invention uses a ring-shaped energized coil to form a continuous and stable spatial-temporally varying magnetic field on the outer wall of an intestinal model as the track moves. This magnetic intestinal villus array on the inner wall of the model generates coordinated asynchronous oscillations with phases staggered in sequence, thereby realistically reproducing the propulsive peristaltic waves of the small intestinal wall in vitro. This provides a highly biomimetic experimental platform for studying the processes of intestinal substance transport, mixing, and absorption.

[0029] Real-time monitoring and quantitative analysis: This invention integrates an external camera and fixation device, which can be stably fixed on the outer wall of the intestinal model and perform real-time imaging and recording of the movement state of the villi inside the model, providing accurate experimental data support for subsequent image recognition, kinematic analysis and drug delivery efficiency evaluation.

[0030] Modular structure and highly adjustable parameters: This invention adopts a modular track-coil combination design. The coil units can be added or removed as needed, the track length can be flexibly adjusted, and the speed and amplitude of the peristaltic wave can be controlled by parameters such as current intensity, frequency and phase difference. It can adapt to various experimental needs and pathological state simulations, significantly improving the applicability and scalability of the system. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the experimental model of artificial small intestinal villi biomimetic peristalsis driven by a changing magnetic field in an embodiment of the present invention.

[0032] Figure 2 This is a schematic diagram of the magnetic cilia distribution in the cross-section of the tubular artificial small intestine villi in an embodiment of the present invention.

[0033] In the figure: 1 Camera and fixing device, 1-1 Camera, 1-2 Fixture, 2 Intestinal model, 2-1 Flexible long cylindrical structure, 2-2 Magnetic villous array, 3 Motor track and ring-shaped energized coil assembly, 3-1 Ring-shaped energized coil, 3-2 Intermediate beam structure, 3-3 Track assembly. Detailed Implementation

[0034] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0035] like Figure 1As shown, the artificial small intestinal villi biomimetic peristalsis experimental model driven by a changing magnetic field provided by the present invention includes: a camera and fixing device 1, used for real-time imaging and recording of the inside of the intestinal model 2, and providing mechanical support for the artificial small intestinal villi biomimetic peristalsis experimental model, including camera 1-1 and fixing frame 1-2; intestinal model 2, including a flexible long cylindrical structure 2-1, the inner wall surface of which is uniformly distributed with a magnetic villi array 2-2, the magnetic villi array 2-2 is a soft artificial small intestinal villi array containing magnetic particles; motor track and ring-shaped energized coil assembly 3, which mainly consists of a drive motor, a ring-shaped energized coil 3-1, a middle beam structure 3-2 and track assembly 3-3.

[0036] Camera 1-1 is nearly cubic in shape, with external dimensions of 10 cm × 10 cm. Internally, it integrates an image sensor chip, optical lens assembly, control circuitry, and data transmission interface. The front end of the lens of camera 1-1 has a 4 cm long extension structure serving as a fixing device 1-2, which is fixed to the outer wall of the intestinal model 2. The fixing device 1-2 includes a support frame and an adjustable angle latch. The support frame connects the front end of the lens and the adjustable angle latch, and is made of a lightweight, high-strength material (such as aluminum alloy). The adjustable angle latch can wrap around and clamp the outer wall of the intestinal model 2. The fixing device 1-2 allows for fine-tuning and locking of the camera 1-1 in both radial and axial positions, ensuring the lens is aligned with the center of the observation area of ​​the intestinal model 2.

[0037] Camera 1-1 is equipped with a shock-absorbing pad to reduce the interference of mechanical vibration generated by the motor track operation on image acquisition. Camera 1-1 is connected to the control and data acquisition unit 2 via wired or wireless means, enabling real-time image display, storage, and subsequent processing and analysis. It is used to monitor the movement state and fluid transport process of the magnetic villus array inside the intestinal model.

[0038] The flexible cylindrical structure 2-1 is formed by winding and sealing a pre-prepared, flat polydimethylsiloxane (PDMS) film, resulting in a hollow cylindrical shape with a length of 20 cm, an inner diameter of 3 cm, and an outer diameter of 4 cm, i.e., a wall thickness of 1 cm. The individual magnetic intestinal villi in the magnetic villous array 2-2 are soft, cylindrical microstructures with a diameter of 0.5 mm and a length of 2 mm, and their matrix material is uniformly mixed with superparamagnetic microparticles. The magnetic villous array 2-2 is uniformly arranged circumferentially and axially along the inner wall, with a distance of approximately 2.27 mm between the tops of adjacent villi, and 36 villi are uniformly arranged around the circumference; along the center of the cylindrical tube, the distance between adjacent cilia is approximately 3 mm.

[0039] The motor track and the ring-shaped energized coil assembly 3 serve as the magnetic field driving module of the artificial small intestinal villi biomimetic peristalsis experimental model. It is used to generate a continuously and stably changing spatial-temporal magnetic field outside the intestinal model 2, thereby driving the magnetic villi array 2-2 on the inner wall of the intestinal model 2 to produce periodic coordinated time-varying oscillations.

[0040] The toroidal energized coil 3-1 is made of conductive metal wire and can generate a stable toroidal magnetic field when energized. The individual coil has a clamp-like structure with an inner diameter of approximately 6 cm and an outer diameter of approximately 8 cm. A 30° notch is cut into the coil ring to allow it to pass over the flexible, elongated cylindrical structure 2-1 of the intestinal model 2 during assembly and operation, enabling the toroidal energized coil 3-1 to pass over and encircle the outer wall of the intestinal model 2 without interference. The toroidal energized coil 3-1 has wire interfaces at both ends, which can be connected to a control power supply. The magnetic field strength and phase can be controlled by adjusting the current magnitude and the on / off sequence.

[0041] The toroidal energized coil 3-1 is connected to the track assembly 3-3 via an intermediate beam structure 3-2. Each intermediate beam is 16cm long, with one end fixedly connected to the outside of the coil and the other end fixedly connected to the track plate. The intermediate beams are made of high-strength, lightweight materials (aluminum alloy or carbon fiber reinforced plastic) to ensure operational stability while reducing the system's inertial load. Multiple coils can be installed in the entire magnetic drive system, each coil being fixed to the corresponding track plate via an intermediate beam, enabling it to circulate along the outer wall of the intestinal model in a track-like manner under the drive of the track movement.

[0042] The track assembly 3-3 consists of several track plates connected end to end in a hinged manner to form a closed loop transmission chain, which is driven by a motor to perform cyclical motion.

[0043] The device was applied to an intestinal model approximately 20 cm in length. An electromagnetic coil was installed on each track plate. First, considering the physical thickness t of the coil itself... coil The minimum physical value for the center-to-center spacing d is 2 cm. Furthermore, magnetic field interference must be avoided. It is preferable to leave a sufficiently large net gap g between adjacent coils, such as approximately 5 cm. This means the minimum threshold for the center-to-center spacing d is... min It should be 2 cm + 5 cm = 7 cm. Secondly, according to experimental verification, the wavelength should generally be less than half the length of the working area, i.e., the flexible cylindrical structure 2-1, to ensure that at least half of the waveform can be accommodated to form an effective drive. Therefore, the upper limit of the wavelength d... maxThe value is set to 20 cm / 2 = 10 cm. Therefore, the reasonable range for the center spacing d is determined to be 7 cm to 10 cm. Within this preferred range, for example, using 8 cm as a specific implementation value, ensures that the net gap between the coils is sufficient to avoid magnetic field interference, while also guaranteeing that the wavelength efficiently generates propulsive force within the intestinal model. This spacing design corresponds to the target wavelength λ of the metachronal wave generated by the magnetic villus array in the intestine, allowing the magnetic fields generated by adjacent coils to act sequentially on the villus array with a certain phase difference, thereby forming a propulsive peristaltic wave in space, similar to a physiological state.

[0044] The above design fully considers the dense arrangement of the villous microstructures on the small intestinal wall and the physiological characteristics of its peristaltic propulsion waves with spatial phase difference, in order to meet the needs of biomimetic reproduction and controllable experimental simulation of intestinal peristalsis in an in vitro environment. Several specific implementation steps are given below:

[0045] Preparation of magnetic artificial intestinal villi: First, polydimethylsiloxane (PDMS) was selected as the flexible matrix material, and 25% by mass of ferromagnetic microparticles (such as hydroxyl Fe particles) were uniformly incorporated. The mixture was thoroughly stirred at room temperature to form a uniformly dispersed magnetic elastic composite precursor liquid. Then, this mixture was injected into a micromold array. The micromold had micropores with a diameter of approximately 0.5 mm and a depth of approximately 2 mm, arranged in a ring pattern of 36 micropores per row. After vacuum degassing in a vacuum environment, excess liquid was gently scraped off along the mold surface with a scraper, ensuring that the magnetic PDMS material remained only within the micropores, keeping the mold surface smooth. Subsequently, a layer of pure PDMS mixture (without magnetic particles) with a thickness of approximately 0.5 mm was uniformly covered on the filled mold surface to form a flexible substrate layer, allowing it to naturally contact and bond with the magnetic PDMS liquid within the micropores. The entire assembly was then cured in a 70 ℃ constant temperature oven for 2 hours, allowing the magnetic PDMS within the micropores and the surface PDMS substrate layer to simultaneously solidify into a single unit. After curing, the entire unit is demolded from the mold to obtain an artificial intestinal villus array unit with a flexible PDMS film at the bottom and a large number of magnetic flexible micropillars arranged vertically on the surface.

[0046] Inward winding assembly of the magnetic flock array film: Lay the obtained magnetic flock array 2-2 film flat on the worktable with the flock facing upward, confirming that the magnetic flock array 2-2 is intact and undamaged. Prepare a stainless steel cylindrical mandrel with a diameter of approximately 2.8 cm, and tightly wrap a layer of soft elastic material (such as polyurethane foam) with a thickness of approximately 1-2 mm on its outer surface to form a flexible buffer layer to avoid scratching or crushing the magnetic flock structure during winding. Then, gently attach the array film along its long side to the mandrel covered with the buffer layer, with the flock facing the inner surface of the mandrel, and slowly and evenly wind it from one end, so that the film fits tightly against the surface of the mandrel and the flock array faces the inner cavity, until a complete closed cylinder is formed. After winding, apply a small amount of uncured PDMS mixture to the film overlap seam, and gently wrap and fix it with an external flexible silicone sleeve. Secondary curing at 70 ℃ for 2 hours to firmly bond the overlap seam to the body into a whole. After cooling, the cylindrical structure is extracted from the mandrel to obtain a flexible, long cylindrical intestinal model component with an inner wall uniformly covered by an array of magnetic artificial small intestinal villi.

[0047] Assembly of the track-coil drive system: First, several track plates are made from high-strength, lightweight materials. Each track plate is 8 cm long and 4 cm wide. They are assembled into a closed loop chain by connecting them end-to-end with metal hinges, forming a ring track. The track is installed between two parallel drive wheels and driven wheels, with the drive wheels driven by a variable-speed DC motor. Second, the intermediate beam structure is fabricated. Slender beams approximately 16 cm long are machined from aluminum alloy. Each beam has a mounting hole at one end for fixing the ring-shaped energized coil, and a rotatable bolt interface at the other end for fixing to the track plate. Multiple intermediate beams are evenly distributed (8 cm) along the track movement direction and installed on the track plates. Next, the ring-shaped energized coil is fabricated. Conductive metal enameled wire is wound into several clamp-shaped ring coils, with an inner diameter of approximately 6 cm and an outer diameter of approximately 8 cm. A notch of approximately 30° is reserved on the ring to avoid interference with the intestinal model during assembly. Electrical connection terminals are provided at both ends of the coil for connection to an external current control module. Each annular coil is fixed to the free end of the corresponding intermediate beam, so that the center of the coil is concentric with the axis of the intestinal model and the plane of the coil is perpendicular to the direction of the track movement.

[0048] The principle of magnetic field-driven villus array oscillation: The coil system described in this invention continuously circulates along the outer wall of the intestinal model under the drive of a motor. A fixed current is sequentially passed through the coil, creating a continuously changing magnetic field that moves with time in the circumferential and axial directions on the outer wall of the intestinal model. Each magnetic artificial intestinal villus contains ferromagnetic particles and can be considered as a combination of a flexible elastic rod and an embedded magnetic dipole. When placed in an external magnetic field B, the magnetic dipole moment m within the villus is subjected to a magnetic torque, causing it to oscillate around its root. This torque is given by the following formula.

[0049]

[0050] When the direction of the applied magnetic field changes, the magnetic dipole moment tends to realign with the magnetic field direction, thereby driving the flexible villi to rotate and deform around their roots, achieving deflection along the direction of the magnetic field lines. As the conveyor belt moves the coils along the outer wall of the intestinal model, there is a phase shift in the magnetic field strength at spatially adjacent positions. The direction and magnitude of the magnetic field gradient experienced by the villi change continuously over time, causing the villi to undergo periodic deflection and recovery movements under the elastic constraint at their roots. Because multiple coils are equidistantly arranged on the conveyor belt, they sequentially pass over the intestinal model as the belt moves, forming a magnetic field phase wave propagating along the model's axis. This results in a phase difference in the oscillation of adjacent villi, thus exhibiting an overall axially propagating time-varying wave. This time-varying wave is a key dynamic feature propelling substances forward within the intestine, thus achieving a biomimetic reproduction of physiological peristaltic waves.

[0051] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A biomimetic peristaltic experimental model of artificial small intestinal villi driven by a changing magnetic field, characterized in that, include: The camera and fixing device (1) are used to perform real-time imaging and recording of the inside of the intestinal model (2), and at the same time provide mechanical support for the artificial small intestinal villi biomimetic peristalsis experimental model to ensure stability during the observation process. The intestinal model (2) includes a flexible long cylindrical structure (2-1) with a magnetic villus array (2-2) evenly distributed on its inner wall surface. The magnetic villus array (2-2) is a soft artificial small intestinal villus array containing magnetic particles, used to simulate the three-dimensional structural morphology of the small intestinal villus and its movement characteristics under physiological conditions. The motor track and ring-shaped energized coil assembly (3) includes a drive motor, a ring-shaped energized coil (3-1), a middle beam structure (3-2), and a track assembly (3-3). The drive motor drives the track assembly (3-3) to move cyclically, so that the ring-shaped energized coil (3-1) moves continuously along the outer wall of the intestinal model (2). By controlling the energization, a time-varying spatial magnetic field is generated, thereby driving the magnetic villus array (2-2) inside the intestinal model (2) to generate a coordinated oscillation with a phase difference, thus realizing the biomimetic simulation of the peristaltic wave of the small intestine.

2. The experimental model of artificial small intestinal villi biomimetic peristalsis driven by a changing magnetic field according to claim 1, characterized in that, The camera and fixing device (1) includes a camera (1-1) and a fixing frame (1-2); the camera (1-1) is cubic in shape and preferably integrates an image sensor chip, an optical lens assembly, a control circuit and a data transmission interface; the front end of the lens of the camera (1-1) is provided with a fixing frame (1-2) and fixed to the outer wall of the intestinal model (2).

3. The experimental model of artificial small intestinal villi biomimetic peristalsis driven by a changing magnetic field according to claim 2, characterized in that, The fixing frame (1-2) includes a support frame and an adjustable angle buckle. The support frame connects the front end of the lens and the adjustable angle buckle. It is made of lightweight and high-strength material. The adjustable angle buckle can wrap around and clamp the outer wall of the intestinal model (2). The fixing frame (1-2) can realize the fine adjustment and locking of the camera (1-1) in the radial and axial positions, so that the lens is aligned with the center of the observation area of ​​the intestinal model (2).

4. The biomimetic peristaltic experimental model of artificial small intestinal villi driven by a changing magnetic field according to claim 1, characterized in that, The camera (1-1) is equipped with a shock-absorbing pad to reduce the interference of mechanical vibration generated by the motor track operation on image acquisition. The camera (1-1) is connected to the control and data acquisition unit by wired or wireless means, which can realize real-time image display, storage and subsequent processing and analysis, and is used to monitor the motion state and fluid transport process of the magnetic villi array inside the intestinal model (2).

5. The biomimetic peristaltic experimental model of artificial small intestinal villi driven by a changing magnetic field according to claim 1, characterized in that, The flexible cylindrical structure (2-1) is formed by rolling and sealing a pre-prepared flat polydimethylsiloxane membrane, and the whole is in the shape of a hollow cylinder with a size that matches the size of the small intestine.

6. The experimental model of artificial small intestinal villi biomimetic peristalsis driven by a changing magnetic field according to claim 1, characterized in that, The individual magnetic intestinal villi in the magnetic villi array (2-2) are soft cylindrical microstructures, and their matrix material is uniformly mixed with superparamagnetic microparticles; the magnetic villi array (2-2) is uniformly arranged along the inner wall circumferentially and axially.

7. The experimental model of artificial small intestinal villi biomimetic peristalsis driven by a changing magnetic field according to claim 1, characterized in that, The motor track and the ring-shaped energized coil assembly (3) serve as the magnetic field driving module of the artificial small intestinal villi biomimetic peristalsis experimental model. It is used to generate a continuously stable and changing spatial-temporal magnetic field outside the intestinal model (2), thereby driving the magnetic villi array (2-2) on the inner wall of the intestinal model (2) to generate periodic coordinated time-varying oscillations.

8. The experimental model of artificial small intestinal villi biomimetic peristalsis driven by a changing magnetic field according to claim 1, characterized in that, The ring-shaped energized coil (3-1) is made of conductive metal wire and can generate a stable ring magnetic field after being energized. The individual coil has a clamp-shaped structure and a 30° notch is provided on the coil ring to avoid the flexible long cylindrical structure (2-1) of the intestinal model (2) during assembly and operation, so that the ring-shaped energized coil (3-1) can pass over and hug the outer wall of the intestinal model (2) without interference. The ring-shaped energized coil (3-1) has wire interfaces at both ends, which can be connected to the control power supply. The magnetic field strength and phase can be controlled by adjusting the current magnitude and the on / off sequence.

9. The experimental model of artificial small intestinal villi biomimetic peristalsis driven by a changing magnetic field according to claim 1, characterized in that, The annular energized coil (3-1) and the track assembly (3-3) are connected by an intermediate beam structure (3-2); furthermore, the track assembly (3-3) is formed by several track plates connected end to end in a hinged manner to form a closed loop transmission chain, which is driven by a motor to perform cyclic motion.

10. The experimental model of artificial small intestinal villi biomimetic peristalsis driven by a changing magnetic field according to claim 1, characterized in that, The center-to-center distance d between two adjacent track plates is set to a predetermined value, which corresponds to the target wavelength λ of the propulsive time-varying wave generated by the changing magnetic field, i.e.: ； When the electromagnetic coil array moves in a cycle, the magnetic field it generates can act on the target object sequentially with a phase difference, thereby forming a propulsive creeping wave in space; the specific principle for selecting the center spacing is as follows: Lower bound constraint: The spacing d must be greater than a minimum threshold d min This minimum threshold is determined by two factors: one is the physical thickness t of the electromagnetic coil itself. coil Secondly, the minimum safety gap g required to avoid interference between the magnetic fields of adjacent coils. min ; Upper limit constraint: The spacing d must be less than a maximum threshold d max If the spacing is too large, the resulting wave will become discontinuous in space and will not be able to form an effective time-separated wave, thus losing its propulsive creep driving effect.

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