A magnetically heat-responsive capsule system capable of site-specific deployment and rapid release

Abstract

The application discloses a kind of magnetic heat response capsule systems of fixed-point deployment and quick release, belong to capsule delivery technical field.System includes magnetic heat response capsule, magnetic control drive module and remote trigger module;Magnetic heat response capsule includes elastic upper cover, locking layer and substrate;Substrate is equipped with the recess for accommodating load, elastic upper cover covers on substrate after overturning, and is fixedly connected with substrate by locking layer, to realize load sealing and transport protection;Locking layer has magnetic heat response characteristic, located in the upper outer edge area of substrate, maintains the overturning locking state of elastic upper cover under normal state;Capsule can be moved to target area under the action of magnetic control drive module, and locking layer is failed under the action of remote trigger module, the constraint to overturning elastic upper cover is released, and elastic upper cover is quickly restored to original configuration by relying on its own elastic energy storage, to realize quick, controllable uncoating process and load fixed-point release at target position.

Description

Technical Field

[0001] This invention belongs to the field of capsule delivery technology, specifically relating to a magnetocaloric response capsule system that can be deployed at a fixed point and released rapidly. Background Technology

[0002] In applications such as in vivo delivery, local therapy, microdevice manipulation, and targeted deployment, commonly used delivery methods include injection delivery, catheter delivery, biodegradable carrier delivery, and capsule delivery. Among these, capsule delivery shows great promise in gastrointestinal and other in vivo scenarios due to its advantages such as the ability to form an independent cavity, provide sealed protection for the internal payload, facilitate overall transportation, and suitability for oral administration or placement in complex environments. Especially for payloads such as microrobots, drugs, local therapeutic devices, and sensors, capsule systems can not only provide physical isolation and protection during transportation but also release the internal payload by opening the capsule upon arrival at the target location.

[0003] However, existing capsule delivery methods still have significant shortcomings. One type of capsule mainly relies on shell degradation, material dissolution, or environmental response to release. Its opening process is greatly affected by acidic or alkaline environments, enzymatic action, or natural erosion conditions, often resulting in unclear release timing, inaccurate positioning, and difficulty in external active control. Another type of capsule uses mechanical opening and closing structures, snap-fit ​​structures, or actively driven components to open. While offering some controllability, these methods are typically more complex, larger in size, and more difficult to manufacture and assemble, hindering miniaturization and system integration. Existing technologies suffer from at least the following shortcomings:

[0004] 1) Existing capsule systems lack system designs for targeted deployment and rapid release of various payloads.

[0005] Existing capsules mostly focus on drug release or general encapsulation, which is insufficient to meet the needs of targeted deployment and rapid release of various payloads such as microrobots, drugs, local therapeutic devices, and sensors.

[0006] 2) Existing capsule release methods lack simple, clear, and controllable opening and release mechanisms.

[0007] Some existing capsules rely on shell degradation, material dissolution, or environmental response to open. Their triggering process is greatly affected by acid and alkaline environments, enzyme action, or natural erosion conditions, resulting in unclear opening timing, inaccurate positioning, and difficulty in external active control. Other capsules use mechanical opening and closing structures, snap-fit ​​structures, or active drive components to open. Although they have a certain degree of controllability and some solutions can be remotely triggered, they usually require additional mechanical transmission components, connectors, or drive components, resulting in a more complex overall structure, larger size, and higher processing and assembly difficulty, which is not conducive to miniaturization and system integration.

[0008] 3) Existing capsule systems cannot simultaneously meet the dual requirements of stable protection during transportation and rapid opening and release at the target location.

[0009] In complex environments such as the gastrointestinal tract, capsule systems are affected by body fluid infiltration, tissue adhesion, and gastrointestinal motility during delivery. Therefore, they need to maintain stable sealing to protect the internal load from external environmental interference. However, once the capsule reaches the target location, it needs to open rapidly upon external signal activation to release the load promptly. Existing delivery systems often struggle to meet both requirements simultaneously: highly sealed structures tend to open slowly or have insufficient openings, while easily deployable structures may lack sufficient protective capabilities during delivery, leading to premature load leakage. Therefore, existing capsule systems still struggle to simultaneously achieve stable transport protection and rapid, reliable release upon arrival.

[0010] Therefore, it is necessary to provide a capsule system that is simple in structure, suitable for remote triggering, and can balance stable carrying and rapid release, so that it can effectively protect the internal load during transportation, and trigger the failure of the locking layer and quickly open the capsule after reaching the target location through an external alternating magnetic field, thereby realizing the fixed-point deployment and rapid release of the internal load. Summary of the Invention

[0011] The purpose of this invention is to overcome the defects in the prior art and provide a magnetorothermal response capsule system that can be deployed at a fixed point and released quickly. This system can stably carry and protect the internal load during transportation. After reaching the target location, the locking layer is triggered by a remote triggering module to release the constraint on the elastic cover. The elastic cover is then restored to achieve rapid opening, thus taking into account stable transportation, remote triggering, fixed-point deployment and rapid release.

[0012] The specific technical solution adopted in this invention is as follows:

[0013] In a first aspect, the present invention provides a magnetothermal response capsule system that can be deployed at a fixed point and released quickly, including a magnetothermal response capsule, a magnetically controlled drive module and a remote triggering module;

[0014] The magnetocaloric response capsule includes an elastic top cover, a locking layer, and a base. The base has grooves, cavities, or load compartments for accommodating the load. The elastic top cover flips over and covers the base, and is fixedly connected to the base through the locking layer to achieve load sealing and transportation protection. The locking layer has magnetocaloric response characteristics and can maintain the flipped and locked state of the elastic top cover under normal conditions. The magnetocaloric response capsule can be moved to the target area under the action of the magnetically controlled drive module, and the locking layer can be disabled under the action of the remote trigger module, releasing the constraint on the elastic top cover. The elastic top cover can then quickly restore its original configuration by relying on its own elastic energy storage, realizing the opening of the capsule and the fixed-point release of the load.

[0015] Preferably, the substrate is prepared by 3D printing, molding, injection molding, machining or photopolymerization, and the material is one of polylactic acid, polycaprolactone, polylactic acid-glycolic acid copolymer, polyurethane, biocompatible resin, or biodegradable polymer material.

[0016] Preferably, the upper outer edge region of the substrate is provided with an installation area for bonding or supporting the locking layer. The installation area is one or more of the following: a continuous annular edge, a continuous annular protrusion, a partial protrusion, a segmented protrusion, a stepped surface, a groove, or a roughened bonding surface.

[0017] Preferably, the locking layer is a magnetocaloric responsive soft material, including magnetocaloric responsive hydrogel, soft polymer, soft elastomer, phase change soft material or gel-elastomer composite material; the magnetocaloric responsive hydrogel includes a main matrix, a functional adjustment component and a magnetic component, and the mass ratio of the main matrix, the functional adjustment component and the magnetic component is (5-30):(0.1-10):(1-40). The main matrix comprises one or more of gelatin, polyvinyl alcohol, gelatin methacrylamide, cellulose derivatives, chitosan, water-soluble polysaccharides and their derivatives; the functional regulating components are used to regulate thermal transition temperature, gel strength, adhesion, swelling, mechanical stability or in vivo adaptability, and include one or more of carrageenan, agar, alginate, pectin, xanthan gum, guar gum, hyaluronic acid, polyethylene glycol, polyacrylamide, polyacrylic acid, poly-N-isopropylacrylamide, poloxamer, crosslinking agents, plasticizers, thickeners or biocompatible inorganic fillers; the magnetic components are used to provide magnetothermal response capability and are at least one of magnetite, iron oxide, ferrite, surface-modified magnetic particles or biocompatible coated magnetic particles.

[0018] Preferably, the locking layer is fixed to the installation area by means of adhesive bonding, embedding, snap-fitting, or limiting; the locking layer is one or more structural forms among annular, strip-shaped ring, continuous encirclement, segmented encirclement, partial bridging, or multi-point support, used to lock the flipped elastic cover above the base.

[0019] Preferably, the material of the elastic cover is at least one of polydimethylsiloxane, Ecoflex, silicone rubber, polyurethane elastomer, thermoplastic elastomer, and PET elastic composite structure.

[0020] Preferably, the elastic cover is a monostable, reversible shell, comprising an arc-shaped main body for covering the base and an edge connecting part located on its outer periphery; the arc-shaped main body is one of an arc shell, a dome shell, a shallow shell, an annular shell, an eccentric shell, or a locally reinforced shell, and the edge connecting part is used to contact and fix with the locking layer; the elastic cover is in a stable original configuration when unconstrained; the elastic cover is flipped in the assembled state and has a certain elastic potential energy, that is, it is flipped in the opposite direction of the original configuration, so that its original inner surface is flipped to the outside, and it is fixed above the base by the locking layer to form a closed cavity and maintain the closed state of the magnetocaloric response capsule; when the locking layer fails under the action of the remote triggering module, the flipped elastic cover returns to the original configuration under the action of its own pre-stored elastic potential energy, thereby opening the magnetocaloric response capsule and releasing the load.

[0021] Preferably, the magnetically controlled drive module is an external magnetic field generator capable of generating a controllable magnetic field or magnetic field gradient, used to drive the magnetocaloric response capsule to move or adjust its posture; the external magnetic field generator includes one or more of a permanent magnet, electromagnet, coil system, magnetic navigation system or medical magnetic resonance imaging device.

[0022] Preferably, the remote triggering module is a magnetic field generating device capable of generating an alternating magnetic field, used to induce a magnetocaloric effect in the magnetic components of the locking layer, thereby inducing the locking layer to fail; the magnetic field generating device includes one of an alternating magnetic field generator, an induction heating device, a radio frequency magnetic field generating device, a high frequency magnetic field generating device, an electromagnetic induction heating device, or a magnetocaloric triggering platform.

[0023] Secondly, the present invention provides a method of using the magnetic thermal response capsule system capable of point-deployment and rapid release as described in any one of the first aspects, as follows:

[0024] S1: The load is loaded into the groove, cavity or load chamber of the base, and the elastic cover flips over and covers the base; by using the locking layer pre-set in the base mounting area, the lower edge of the flipped elastic cover is fixedly connected to the upper outer edge of the base, thereby locking the flipped elastic cover above the base and forming a sealed load for the load.

[0025] S2: The assembled magnetocaloric response capsule enters the target environment and then moves to the target position along a preset path under the action of the magnetic drive module;

[0026] S3: The locking layer of the magnetocaloric response capsule is stimulated by the remote triggering module, causing the locking layer to fail and lose its ability to seal and fix the elastic cover; the elastic cover returns to its original configuration by relying on its elastic energy storage, the magnetocaloric response capsule is opened, and the load is released.

[0027] Compared with the prior art, the present invention has the following advantages:

[0028] 1) This invention provides a magnetocaloric response capsule system suitable for the fixed-point deployment and rapid release of various loads. It can form a closed cavity during transportation, effectively bearing and protecting the internal loads. The closed structure, formed by the base, locking layer, and elastic top cover, reduces the impact of external liquid environments, adhesive environments, and mechanical disturbances on the internal loads, thereby improving the transport stability of the loads in complex environments and facilitating the smooth implementation of subsequent fixed-point deployment.

[0029] 2) In this invention, the magnetic thermal response capsule has a relatively simple mechanical structure, is easy to process and assemble, and is convenient for engineering implementation. This invention mainly consists of a base, a locking layer, and an elastic top cover. It achieves functions such as closed protection, remote opening, and robot release without the need for complex transmission mechanisms, precision linkage components, or multi-stage release assemblies. This simple structure has a high degree of integration and can be realized using conventional processes such as 3D printing, elastic material molding, and hydrogel preparation, demonstrating good manufacturing feasibility and application transformation potential.

[0030] 3) This invention enables remote opening of the capsule via a remote triggering module, resulting in a clear, gentle, and controllable opening process. Compared to existing solutions that rely on the overall disintegration of the shell, material dissolution, or strong external field damage, this invention achieves the failure of the locking layer through magnetothermal response and releases the constraint on the elastic cover after flipping. The elastic cover then restores its original configuration by relying on its own elastic energy storage to open the capsule. Therefore, it can achieve a more clear, faster, and controllable opening process at the target location.

[0031] 4) This invention effectively balances the need for secure sealing during transport with the ability to open quickly upon arrival. During transport, the locking layer secures the flipped elastic cover to the base, keeping the capsule closed. Upon reaching the target location, a remote trigger module deactivates the locking layer, allowing the elastic cover to quickly return to its original shape and open the capsule. Thus, this invention simultaneously satisfies the requirements of "stable transport" and "rapid opening," overcoming the difficulty of achieving both simultaneously in existing technologies.

[0032] 5) This invention facilitates the subsequent release and targeted deployment of the internal load. After the capsule is opened, external driving methods such as magnetic drive modules, or combined with gravity, fluid propulsion, etc., can be used to release and remove the internal load from the capsule and guide it to a designated location. Therefore, this invention is not only suitable for the protected transport of loads, but also for the targeted deployment and subsequent operation of loads in a target area.

[0033] 6) This invention has good system integration and scalability. It integrates payload protection and transportation, remote opening and release deployment into a single capsule carrier, applicable to both single payloads and payload groups, and can be further extended to microrobots, drug payloads, local therapeutic devices, sensors, and other functional payload systems, demonstrating broad application prospects. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of a preferred embodiment of the magnetocaloric response capsule structure of the present invention;

[0035] Figure 2 This is a schematic diagram of the working process of the magnetocaloric response capsule system;

[0036] Figure 3 This is a photograph of a preferred embodiment of the present invention showing the shell being flipped back to its original configuration.

[0037] Figure 4 This is a schematic diagram of the opening process of a magnetocaloric response capsule under an alternating magnetic field, according to a preferred embodiment of the present invention.

[0038] The attached diagram is labeled as follows: 1. Elastic top cover; 2. Locking layer; 3. Base; 4. Load. Detailed Implementation

[0039] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below. Technical features in various embodiments of the present invention can be combined accordingly without mutual conflict.

[0040] This invention provides a magnetocaloric response capsule system that can be deployed at a fixed location and released quickly. The magnetocaloric response capsule system mainly includes a magnetocaloric response capsule, a magnetically controlled drive module, and a remote triggering module. Through the cooperation of the three, the transportation, opening, release, and deployment of the internal load of the magnetocaloric response capsule can be realized.

[0041] Specifically, such as Figure 1As shown, the magnetocaloric responsive capsule of the present invention mainly includes a base 3, a locking layer 2 disposed on the upper outer edge region of the base 3, a flip-up elastic cover 1 disposed on the base 3, and a load 4 loaded inside the base 3. The base 3 has a groove, cavity, or load compartment inside to bear the load 4 and provide mechanical support; the locking layer 2 is fixed to the upper outer edge region of the base 3; the elastic cover 1 flips over and covers the base 3, and is fixedly connected to the base 3 through the locking layer 2, achieving sealed loading of the internal load 4. The locking layer 2 has magnetocaloric responsive characteristics, and under normal conditions, it can fix the flipped elastic cover 1 on the base 3 to form a closed cavity; under the action of a remote triggering module, the locking layer 2 can undergo magnetocaloric softening, phase change, liquefaction, or other forms of failure, thereby losing its fixing function and releasing the constraint on the flipped elastic cover 1. After the locking layer 2 releases the constraint, the elastic cover 1 can restore its original configuration, realizing the opening of the capsule and releasing the load 4.

[0042] In a preferred embodiment of the present invention, the capsule as a whole can adopt a microstructure suitable for gastrointestinal transport or other complex environments, such as a cylindrical, elliptical cylindrical, spherical, box-shaped, shallow cavity-shaped, or other hollow carrier structure. The overall size of the assembled capsule can be adjusted according to the usage scenario; for example, the overall diameter can be 3–15 mm and the height can be 2–15 mm.

[0043] In a preferred embodiment of the present invention, the substrate 3 is a structural component used to bear the load 4 and support the locking layer 2 and the elastic cover 1. The substrate can be prepared by 3D printing, molding, injection molding, machining, or photopolymerization. Its materials may include, but are not limited to, polylactic acid (PLA), polycaprolactone (PCL), polylactic-co-glycolic acid copolymer (PLGA), polyurethane, biocompatible resin, biodegradable polymer materials or composite materials thereof, which have good biocompatibility.

[0044] The grooves, cavities, or load cells formed in the base 3 can be cylindrical, square, annular, elliptical, or other structures suitable for loading the load 4. For example... Figure 1 As shown, a square groove can be formed in the center of the base 3 to hold the microrobot as a load 4. The upper outer edge of the base 3 has a mounting area for mounting the locking layer 2. The mounting area can be a continuous annular protrusion, a partial protrusion, a segmented boss, a stepped surface, or other structures suitable for bonding and supporting the locking layer 2.

[0045] In a preferred embodiment of the present invention, the locking layer 2 is a magnetocalorically responsive soft material. Its function is to fix the flipped elastic cover 1 above the base 3 under normal conditions, so that the base 3 and the flipped elastic cover 1 together form a closed cavity, thereby achieving closed protection for the internal load 4 (e.g., a micro-robot). Under the action of a remote triggering module (e.g., an alternating magnetic field), the locking layer 2 undergoes magnetocalorically softening, phase change, liquefaction, or other failure behaviors, thereby losing its fixing function and releasing the constraint on the elastic cover 1.

[0046] Magnetothermic soft materials can be composed of one or more soft material systems, including but not limited to magnetothermic hydrogels, soft polymers, soft elastomers, phase change soft materials, gel-elastomer composites, or other material systems that can change their mechanical state and lose their fixed function under magnetothermal action.

[0047] In a preferred embodiment, the locking layer 2 is made of magnetothermal responsive hydrogel. The magnetothermal responsive hydrogel includes a main matrix, functional regulating components, and a magnetic component. The main matrix includes one or more of gelatin, polyvinyl alcohol, gelatin methacrylamide, cellulose derivatives, chitosan, water-soluble polysaccharides, and their derivatives. The functional regulating components are used to regulate thermal transition temperature, gel strength, adhesion, swelling, mechanical stability, and in vivo adaptability, and include one or more of carrageenan, agar, alginate, pectin, xanthan gum, guar gum, hyaluronic acid, polyethylene glycol, polyacrylamide, polyacrylic acid, poly(N-isopropylacrylamide), poloxamer, crosslinking agents, plasticizers, thickeners, pH adjusters, or biocompatible inorganic fillers. The magnetic component provides magnetothermal responsiveness and is at least one of magnetite, iron oxide, ferrite, surface-modified magnetic particles, or biocompatible coated magnetic particles. The preferred mass ratio of the main matrix, functional regulating component, and magnetic component is (5-30):(0.1-10):(1-40).

[0048] By adjusting the ratio of the main matrix, functional regulating components, and magnetic components, the locking layer 2 can possess controllable mechanical retention capability and thermally triggered failure behavior. For example, in a preferred hydrogel embodiment, the gelatin content in the locking layer 2 can be 5 wt% to 30 wt%, the carrageenan content can be 0.1 wt% to 10 wt%, the iron oxide particle content can be 1 wt% to 40 wt%, and the remainder is solvent and auxiliary components. The optimal ratio can be optimized according to the target temperature range, locking strength, triggering efficiency, and application environment.

[0049] In a preferred embodiment of the present invention, the locking layer 2 can be used to mount the flipped elastic cover 1 onto the upper outer edge mounting area of ​​the substrate 3 through annular sleeve, strip-shaped ring, segmented encirclement, partial bridging, multi-point support, or other structural forms. In a preferred embodiment, the locking layer 2 is prepared as a strip-shaped gel sheet with dimensions of 60 × 2 × 1 mm, forming an annular locking layer around the upper outer edge region of the substrate 3. The locking layer 2 can be fixed to the mounting area by adhesive, embedding, snap-fitting, or limiting methods. Adhesion can be achieved using glue, medical adhesive, silicone adhesive, double-sided adhesive, etc.

[0050] In a preferred embodiment of the present invention, the elastic cover 1 is an elastic shell disposed above the base 3. When the locking layer 2 is in its normal or untriggered state, the elastic cover 1 flips over and is fixed by the locking layer 2 to maintain the closed state of the capsule. When the locking layer 2 fails, the elastic cover 1 returns to its original configuration by relying on the pre-stored elastic potential energy, thereby achieving rapid opening. The elastic cover 1 may be made of, but is not limited to, the following materials: polydimethylsiloxane (PDMS), Ecoflex, silicone rubber, polyurethane elastomer, thermoplastic elastomer, PET elastic composite structure or blends thereof.

[0051] In actual use, the elastic top cover 1 is not an ordinary flat membrane, but a monostable, reversible outer shell formed through structural design. Specifically, as shown... Figure 3 As shown, the elastic cover 1 includes an arc-shaped main body for covering the base 3 and an edge connecting part located on its outer periphery. The arc-shaped main body can be an arc shell, a dome shell, a shallow shell, an annular shell, an eccentric shell, a partially reinforced shell, or other structures suitable for flipping and restoring. The edge connecting part is used to contact and fix with the locking layer 2. When the shell is unrestrained, it is in a stable original configuration. During assembly, the elastic cover 1 is flipped in the opposite direction from its original configuration, so that its original inner surface is flipped to the outside and fixed above the base 3 by the locking layer 2 to form a closed cavity. At this time, the flipped elastic cover 1 stores elastic potential energy inside. When the locking layer fails under the action of the remote triggering module, the flipped elastic cover 1 relies on its pre-stored elastic potential energy to restore its original configuration, thereby opening the capsule.

[0052] To prevent excessive restoring force of the elastic cover 1 after flipping, which could lead to tearing of the locking layer or failure of the seal, the flipping force or restoring force of the outer shell can be reduced by adjusting parameters such as the curvature of the main shell, shell thickness, edge area thickness, edge length, and arch height. This ensures that the cover can be stably held in place by the locking layer and can quickly recover and open after the locking layer fails. In a preferred embodiment, the restoring force can be reduced by decreasing the thickness of the edge area of ​​the elastic cover, thereby improving stability in the closed state.

[0053] In a preferred embodiment of the present invention, the payload 4 can be a single or multiple microrobots, drug payloads, local therapeutic devices, sensors, local manipulation tools, soft devices, micro-functional devices, or other objects requiring protected transport and on-demand release and deployment at a target location. The microrobots can be magnetic microrobots, soft microrobots, magnetoelastic composite robots, local manipulation robots, drug-carrying robots, or other micro-devices suitable for in vivo manipulation.

[0054] Microrobots can be fabricated from PDMS / NdFeB magnetic composite materials. The preparation process includes: mixing NdFeB magnetic particles with a PDMS precursor solution, curing to form a magnetic elastomer sheet or block, magnetizing the sheet or block, and then obtaining the desired shape and size of the microrobot through laser cutting, die-cutting, punching, or mechanical cutting. The resulting microrobots can be sheet-like, strip-like, block-like, film-like, microwing-like, microfin-like, or other microstructures suitable for magnetic actuation.

[0055] In a preferred embodiment of the present invention, the magnetically controlled drive module is an external magnetic field generating device capable of generating a controllable magnetic field or magnetic field gradient, used to drive the movement or adjust the posture of the magnetocaloric response capsule, and to control the release, removal, deployment, and subsequent guidance of the internal load after the capsule opens. The external magnetic field generating device includes one or more of a permanent magnet, electromagnet, coil system, magnetic navigation system, or medical magnetic resonance imaging (MRI).

[0056] In a preferred embodiment of the present invention, the remote triggering module is a magnetic field generating device capable of generating an alternating magnetic field, used to induce a magnetocaloric effect in the magnetic components of the locking layer, thereby causing the locking layer 2 to fail. The magnetic field generating device includes one of an alternating magnetic field generator, an induction heating device, a radio frequency magnetic field generating device, a high-frequency magnetic field generating device, an electromagnetic induction heating device, or a magnetocaloric triggering platform. Preferably, a planar electromagnetic coil can be arranged below the capsule to achieve point-to-point triggering.

[0057] Of course, in other embodiments, the locking layer 2 may also be designed to respond to other remote stimulation methods, such as heat, electricity, ultrasound, radio frequency, microwave or combinations thereof, as long as the locking layer 2 can be disabled and the elastic cover 1 can be released from its fixation.

[0058] Utilizing the aforementioned magnetic thermal response capsule system capable of point-to-point deployment and rapid release, this invention also provides a method of use, which is detailed below:

[0059] S1: Load 4 is installed into the inner cavity of the base 3, and the elastic cover 1 is flipped in the opposite direction and fixed above the base 3 by the locking layer 2 to form a sealed load for the load 4.

[0060] S2: The assembled magnetothermal response capsule enters the target environment and then moves to the target position along a preset path under the action of the magnetic control drive module.

[0061] S3: The locking layer 2 of the magnetocaloric response capsule is stimulated using a remote triggering module, causing the locking layer 2 to fail and lose its ability to seal and fix the flip-up elastic cover 1. The elastic cover 1 returns to its original configuration by relying on its elastic energy storage, the magnetocaloric response capsule is opened, and the load 4 is released.

[0062] In a preferred embodiment, the above-described method of use is as follows:

[0063] (1) First, load the load into the groove inside the substrate, then fix the magnetothermal response soft material locking layer around the upper outer edge area of ​​the substrate. Then, flip the elastic top cover in the opposite direction and fix it on the locking layer, so that it is suspended above the substrate to form a closed cavity, thereby completing the capsule assembly.

[0064] (2) The assembled capsule can enter the gastrointestinal environment or other target environment through oral administration, delivery or other means, and move to the target position along a preset path under the action of the external magnetic drive module. During transportation, the elastic cover and the base together form a closed cavity, thereby protecting the internal load.

[0065] (3) Once the capsule reaches the target position, the locking layer is stimulated using a remote triggering module. Preferably, an alternating magnetic field is applied to the magnetic components in the locking layer to generate a magnetocaloric effect, causing the locking layer to fail and thus lose its ability to fix the elastic cap. Subsequently, the elastic cap recovers to its original configuration by relying on its elastic energy storage, and the capsule is quickly opened. In other embodiments, the above-mentioned opening process can also be achieved by thermal stimulation, electrical stimulation, ultrasonic stimulation, radio frequency stimulation, microwave stimulation, or a combination thereof.

[0066] (4) After the capsule is opened, the internal payload is released, removed, or further guided to the target area for deployment using an external magnetic drive module or other external force. For microrobot payloads, it can be further guided to perform local diagnosis and treatment, targeted transport, tissue repair, local cleaning, or other tasks; for other types of payloads, the corresponding release and deployment process can be completed according to their functions.

[0067] The present invention will be specifically described below through examples.

[0068] Example

[0069] This embodiment provides a magnetocaloric responsive capsule system capable of targeted deployment and rapid release, used to achieve protected transport, targeted deployment, and rapid release of payloads. In this embodiment, the locking layer material is hydrogel, and the payload is a microrobot. Details are as follows:

[0070] 1. Substrate preparation

[0071] The capsule substrate was fabricated using 3D printing with polylactic acid (PLA) as the printing material. The resulting substrate was a cylindrical structure with a diameter of 8 mm and a height of 5 mm. A square groove was created at the center of the substrate to accommodate the payload of a microrobot.

[0072] 2. Preparation of the locking layer

[0073] The locking layer is composed of gelatin, carrageenan, and iron oxide (Fe3O4). Specifically, by mass percentage, gelatin accounts for 20 wt%, carrageenan 1 wt%, and iron oxide particles 15 wt%, with the remainder being water or a physiologically compatible liquid medium. Gelatin serves as the main gel matrix, carrageenan is used to adjust the gel-sol phase transition temperature, and iron oxide provides the magnetocaloric response capability. The prepared magnetocaloric responsive hydrogel is coagulated into strip-shaped gel sheets with dimensions of 60 × 2 × 1 mm. Subsequently, the strip-shaped gel sheets are arranged in a ring around the upper outer edge of the substrate and fixed to the outer edge (mounting area) of the substrate using adhesive, thereby forming a ring-shaped locking layer above the substrate.

[0074] 3. Fabrication of Microrobot Payloads

[0075] The microrobots were fabricated using a PDMS / NdFeB composite material. The specific steps were as follows: NdFeB magnetic particles were uniformly mixed with a PDMS precursor solution and then cured to form a magnetic elastomer film; the film was then magnetized, and subsequently, microrobots of the desired size and shape were obtained by laser cutting. After fabrication, the resulting microrobots were placed into a central groove in a substrate.

[0076] 4. Preparation and assembly of the elastic top cover

[0077] The flexible top cover is made of PDMS. The flexible top cover is a monostable flip shell formed by structural design. The flexible top cover includes a circular shell body and a skirt set on the outer periphery of the circular shell body. Before assembly, the flexible top cover is flipped in reverse from its original configuration, so that its original inner surface is flipped to the outside. Then, the edge skirt of the flipped PDMS top cover is fixed to the locking layer with adhesive, so that it is suspended above the base, thereby forming a closed cavity with the base to achieve closed protection for the internal microrobot.

[0078] In this embodiment, the elastic cover structure is parametrically designed to exhibit monostable flipping behavior. Specifically, the elastic cover includes a circular shell body and a skirt portion located on the outer periphery of the circular shell body. The bottom opening diameter of the circular shell body is 10 mm, the shell height is 2.6 mm, and the shell thickness is 1.5 mm. During assembly, the elastic cover can be flipped in reverse from its original configuration, causing its original inner surface to flip to the outside and be fixed to the base by a locking layer to form a closed cavity. After the locking layer fails, it recovers to its original configuration based on its own elastic potential energy. At the same time, by reducing the thickness of the skirt region of the elastic cover to reduce its restoring force, the flipped elastic cover can be stably fixed by the locking layer, avoiding tearing of the locking layer due to excessive restoring force.

[0079] 5. The working process of the capsule

[0080] Figure 2 The diagram shows the capsule's operation. The assembled capsule is placed at the initial experimental position. First, a permanent magnet is used to magnetically control the capsule, moving it along a preset path to the target position. Once the capsule is in place, the permanent magnet is removed, and a planar electromagnetic coil is placed beneath the capsule to apply an alternating magnetic field. Figure 4 The diagram illustrates the capsule opening process. Under the influence of an alternating magnetic field, the magnetite in the locking layer generates a magnetocaloric effect, causing the locking layer to gradually liquefy and lose its fixing effect on the flip-up elastic cover. After the constraint is released, the elastic cover rapidly returns to its original configuration based on its pre-stored elastic potential energy, thus opening the capsule. In this embodiment, the mechanical opening time during the capsule opening process can reach the millisecond level. After the capsule opens, a permanent magnet is used again to magnetically drive and guide the internal microrobot, releasing it from the capsule and deploying it to a designated location for subsequent operations. In this embodiment, the payload is a magnetically controlled microrobot, thus it can be further guided to move to the target area to carry out its work via magnetic control.

[0081] In summary, the present invention provides:

[0082] 1) An overall solution for a magnetocaloric response capsule system for fixed-point deployment and rapid release of payloads.

[0083] This capsule system is a transport and release vehicle designed for various payloads. It can enclose and protect the internal payload during transport and remotely open it at the target location via a remote trigger module. Subsequently, it uses an external drive to release the internal payload and deploy it to a designated area. Payloads include, but are not limited to, microrobots, drugs, local therapeutic devices, sensors, micro-functional devices, or other objects requiring protected transport and on-demand release.

[0084] 2) A capsule structure consisting of a base, a locking layer, and an elastic cap.

[0085] The base is used to bear the internal load and support the locking layer and the elastic cover. The locking layer is set around the upper outer edge area (installation area) of the base. Under normal conditions, it fixes the elastic cover above the base, so that the elastic cover and the base together form a closed cavity. Under the remote triggering module, the locking layer softens, undergoes phase change, liquefaction or other forms of failure, thereby releasing the constraint on the elastic cover. The flipped elastic cover is used to restore the original configuration by relying on elastic energy storage after the locking layer is released, thereby realizing the rapid opening of the capsule.

[0086] 3) Employing magnetocaloric responsive soft materials as remotely switchable soft locking layers and their material systems.

[0087] The soft material locking layer acts as a soft fixing layer or soft adhesive layer during transportation. Under the action of an alternating magnetic field, it loses its fixing function, thereby enabling remote unlocking and opening of the capsule.

[0088] 4) A locking layer is set around the upper outer edge of the base to maintain the arrangement of the closed cavity.

[0089] The locking layer is preferably arranged in the upper outer edge region of the substrate in the form of a ring, circle, strip, continuous encirclement, segmented encirclement, partial bridging, or multi-point support, so as to fix the flip-up elastic cover above the substrate and form a closed structure. This arrangement not only helps to maintain the stable closed state of the capsule during transportation, but also facilitates the rapid release of the constraint on the elastic cover after the locking layer fails.

[0090] 5) A solution that achieves quick opening and stable closing through the structural design of the elastic top cover.

[0091] The elastic top cover is preferably a monostable, flip-top shell formed by structural design. After flipping, it can be fixed to the base by a soft material locking layer, and after the locking layer fails, it relies on elastic energy storage to restore its original configuration, thereby enabling the capsule to open quickly. Preferably, the flipping force or restoring force can be reduced by adjusting geometric parameters such as the curvature of the main shell, the shell thickness, the thickness of the edge area, the edge length, and the arch height, so as to avoid tearing the locking layer and ensure rapid recovery of opening after the locking layer is released.

[0092] 6) A continuous operation process for capsule transportation, remote opening, and payload deployment via an external magnetic field.

[0093] The capsule is guided to its target location using a permanent magnet or other magnetically controlled device. Once in position, an alternating magnetic field is applied to the magnetocalorically responsive soft material locking layer, disabling it and releasing the constraint on the elastic top cover. After the capsule opens, an external magnetic field or other driving method is used to release and remove the internal load from the capsule, guiding it to a designated area for targeted deployment or subsequent operations. This solution utilizes external signals to achieve remote, non-contact control throughout the entire process, suitable for precise triggering and operation within the body or in complex environments.

[0094] 7) Application of the invention in the gastrointestinal tract and other complex environments

[0095] This invention can be used for payload protection transport, targeted opening, rapid release and subsequent deployment in the gastrointestinal tract or other complex environments, and can be extended to other internal cavities, humid and complex environments or payload systems that require stable carrying and on-demand release.

[0096] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, all technical solutions obtained through equivalent substitution or transformation fall within the protection scope of the present invention.

Claims

1. A magnetocaloric response capsule system capable of point-to-point deployment and rapid release, characterized in that, It includes a magnetothermal response capsule, a magnetically controlled drive module, and a remote triggering module; The magnetocaloric response capsule includes an elastic cover (1), a locking layer (2), and a base (3). The base (3) is provided with a groove, cavity, or load compartment for accommodating the load (4). The elastic cover (1) is flipped over and covers the base (3), and is fixedly connected to the base (3) through the locking layer (2) to achieve sealing and transportation protection of the load (4). The locking layer (2) has magnetocaloric response characteristics and can maintain the flipped and locked state of the elastic cover (1) under normal conditions. The magnetocaloric response capsule can be moved to the target area under the action of the magnetic control drive module, and the locking layer (2) is disabled under the action of the remote trigger module, releasing the constraint on the flipped elastic cover (1). The elastic cover (1) then quickly restores its original configuration by relying on its own elastic energy storage, realizing the opening of the capsule and the fixed-point release of the load (4).

2. The magnetocaloric response capsule system capable of fixed-point deployment and rapid release according to claim 1, characterized in that, The substrate (3) is prepared by 3D printing, molding, injection molding, machining or photopolymerization, and the material is one of polylactic acid, polycaprolactone, polylactic acid-hydroxyacetic acid copolymer, polyurethane, biocompatible resin, or biodegradable polymer material.

3. The magnetocaloric response capsule system capable of fixed-point deployment and rapid release according to claim 1, characterized in that, The upper outer edge region of the substrate (3) is provided with an installation area for bonding or supporting the locking layer (2). The installation area is one or more of the following: continuous annular edge, continuous annular protrusion, local protrusion, segmented protrusion, stepped surface, groove or roughened bonding surface.

4. The magnetocaloric response capsule system capable of fixed-point deployment and rapid release according to claim 1, characterized in that, The locking layer (2) is a magnetocalorically responsive soft material, including magnetocalorically responsive hydrogels, soft polymers, soft elastomers, phase change soft materials, or gel-elastomer composite materials; the magnetocalorically responsive hydrogel includes a main matrix, a functional regulating component, and a magnetic component, with a mass ratio of (5-30):(0.1-10):(1-40); the main matrix includes one or more of gelatin, polyvinyl alcohol, gelatin methacrylamide, cellulose derivatives, chitosan, water-soluble polysaccharides, and their derivatives; the functional regulating component... The components are used to adjust the thermal transition temperature, gel strength, adhesion, swelling, mechanical stability, or in vivo compatibility, and include one or more of carrageenan, agar, alginate, pectin, xanthan gum, guar gum, hyaluronic acid, polyethylene glycol, polyacrylamide, polyacrylic acid, poly-N-isopropylacrylamide, poloxamer, crosslinking agents, plasticizers, thickeners, or biocompatible inorganic fillers; the magnetic component is used to provide magnetocaloric response capability and is at least one of magnetite, iron oxide, ferrite, surface-modified magnetic particles, or biocompatible coated magnetic particles.

5. A magnetocaloric response capsule system capable of point-deployment and rapid release according to claim 3 or 4, characterized in that, The locking layer (2) is fixed to the installation area by means of adhesive, embedding, snap-fit ​​or limiting; the locking layer (2) is one or more of the following structural forms: ring-shaped, strip-shaped ring, continuous ring, segmented ring, partial bridging or multi-point support, used to fix the flipped elastic cover (1) above the base (3) by the locking layer.

6. The magnetocaloric response capsule system capable of fixed-point deployment and rapid release according to claim 1, characterized in that, The elastic cover (1) is made of at least one of the following materials: polydimethylsiloxane, Ecoflex, silicone rubber, polyurethane elastomer, thermoplastic elastomer, and PET elastic composite structure.

7. The magnetocaloric response capsule system capable of fixed-point deployment and rapid release according to claim 1, characterized in that, The elastic cover (1) is a monostable reversible shell, including an arc-shaped main body for covering the base (3) and an edge connecting part located on its outer periphery; the arc-shaped main body is one of the following: arc shell, dome shell, shallow shell, annular shell, eccentric shell, and locally reinforced shell; the edge connecting part is used to contact and fix with the locking layer (2); the elastic cover (1) is in a stable original configuration when unconstrained; the elastic cover (1) is flipped in the assembled state and has a certain elastic potential energy, that is, it is flipped in the opposite direction of the original configuration, so that its original inner surface is flipped to the outside, and it is fixed above the base (3) by the locking layer (2) to form a closed cavity and maintain the closed state of the magnetocaloric response capsule; when the locking layer (2) fails under the action of the remote triggering module, the flipped elastic cover (1) returns to the original configuration under the action of its own pre-stored elastic potential energy, thereby opening the magnetocaloric response capsule and releasing the load (4).

8. A magnetocaloric response capsule system capable of fixed-point deployment and rapid release according to claim 1, characterized in that, The magnetic drive module is an external magnetic field generating device capable of generating a controllable magnetic field or magnetic field gradient, used to drive the magnetocaloric response capsule to move or adjust its posture; the external magnetic field generating device includes one or more of a permanent magnet, electromagnet, coil system, magnetic navigation system or medical magnetic resonance imaging instrument.

9. A magnetocaloric response capsule system capable of fixed-point deployment and rapid release according to claim 1, characterized in that, The remote triggering module is a magnetic field generating device capable of generating an alternating magnetic field, used to induce the magnetic components in the locking layer (2) to generate a magnetocaloric effect, thereby inducing the locking layer (2) to fail; the magnetic field generating device includes one of an alternating magnetic field generator, an induction heating device, a radio frequency magnetic field generating device, a high frequency magnetic field generating device, an electromagnetic induction heating device, or a magnetocaloric triggering platform.

10. A method of using the magnetically responsive capsule system capable of point-deployment and rapid release according to any one of claims 1 to 9, characterized in that, Specifically as follows: S1: The load (4) is inserted into the groove, cavity or load chamber of the base (3), and the elastic cover (1) is flipped over and covers the base (3); by using the locking layer (2) pre-set in the mounting area of ​​the base (3), the lower edge of the flipped elastic cover (1) is fixedly connected to the upper outer edge of the base (3), thereby locking the flipped elastic cover (1) above the base (3) to form a sealed assembly of the load (4); S2: The assembled magnetocaloric response capsule enters the target environment and then moves to the target position along a preset path under the action of the magnetic drive module; S3: The locking layer (2) of the magnetothermal response capsule is stimulated by the remote triggering module, causing the locking layer (2) to fail and lose its ability to fix the elastic cover (1); the elastic cover (1) recovers to its original configuration by relying on its own elastic energy storage, the magnetothermal response capsule is opened, and the load (4) is released.

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