Soft drug-loaded capsule robot based on magnetic liquid metal and preparation and driving method thereof

Abstract

The invention relates to the technical field of miniature medical robots, and discloses a magnetic liquid metal-based soft drug-loaded capsule robot, which comprises a soft capsule robot main body, a soft capsule robot cover and a degradable sealing sleeve, the soft capsule soft robot main body comprises a bottom fan-shaped magnetic liquid metal storage cabin, a left fan-shaped medicine storage cabin, a left rectangular medicine release port, a right fan-shaped medicine storage cabin and a right rectangular medicine release port. According to the soft drug-loaded capsule robot based on the magnetic liquid metal and the preparation and driving method of the soft drug-loaded capsule robot, a Helmholtz coil is used for generating a clockwise rotating composite magnetic field on a YZ plane, and anticlockwise rolling of a capsule is achieved through magnetic response of the magnetic liquid metal; the problem of limited energy supply of the micro-robot is solved through driving of an external magnetic field, and movement in any direction and accurate positioning are supported; the gelatin sealing sleeve is melted through external laser irradiation, and instant release of the medicine is achieved (suitable for emergency treatment).

Description

Technical Field

[0001] The present invention relates to the technical field of micro medical robots, and in particular to a soft drug-carrying capsule robot based on magnetic liquid metal and a preparation and driving method thereof. Background Art

[0002] Micro-medical robots have garnered widespread attention and research in recent years. Capsule robots are a typical example of this type of micro-medical robot. Similar in shape and size to a regular capsule, they can be swallowed orally and enter the human stomach to assist in the diagnosis and treatment of diseases. Drug-carrying capsule robots can also reach intestinal or gastric lesions, delivering targeted medication for precise treatment.

[0003] Despite their numerous advantages, microcapsule robots still face significant challenges. First, their safety. Most capsule robots contain permanent magnets, coils, metal parts, and other hard materials, such as non-metallic materials. Ensuring that these robots do not produce harmful chemicals and heavy metals within the human body, or damage the gastrointestinal tract, is a crucial issue. Second, their reliability. Most capsule robots are already small enough, yet they integrate various mechanical structures and tiny components. How can we ensure that these complex structures can achieve their intended goals with reliability? Third, their actuation and control. Some capsule robots utilize internal energy, but due to their small size, their internal energy source is limited. Ensuring sufficient energy supply for successful manipulation is crucial. Furthermore, precise control of the robot's position within the human body is difficult. If the robot cannot reach the designated lesion, its medical mission cannot be completed.

[0004] Traditional drug delivery methods (such as injection or oral administration) have problems with systemic drug circulation, resulting in drug distribution and waste in non-target areas, while increasing the risk of toxic side effects. In contrast, the micro-drug-carrying robot targeted drug delivery system, as a multidisciplinary technological achievement that integrates micro-electromechanical, biology, medicine, and materials science, can effectively solve the problems in traditional medicine. This technology uses a micro-robot carrying drugs to precisely navigate to the lesion site and release the drug in the target area to achieve targeted treatment.

[0005] Published patent application CN119857214A discloses a targeted drug delivery capsule robot based on a soluble film. This robot utilizes a magnetic control system linked to an oscillation module to enable rapid positioning of the capsule robot in the digestive tract. The soluble film controls drug release. However, this solution incorporates a complex mechanical structure and numerous modules, including cameras, radios, and batteries. Miniaturization of the capsule robot is difficult, and the quality and variety of drug delivery are limited.

[0006] Authorized patent application CN115569298B discloses a magnetically controlled micro-soft drug-carrying capsule robot and its preparation and driving method. The robot adopts a degradable soft shell, and after the drug is released, it dissolves harmlessly in the human body. However, there is a problem. The drug-releasing magnetic block is made of a mixture of polydimethylsiloxane (PDMS) and rubidium iron boron (NdFeB) magnetic particles. When the degradable shell dissolves, it is completely exposed to the human body. Although polydimethylsiloxane (PDMS) is difficult to degrade in the body, there is no guarantee that the residue mixed with rubidium iron boron (NdFeB) magnetic particles will be toxic to the human body. Therefore, a magnetically controlled micro-capsule robot with a simple design structure, harmless to the human body, capable of carrying one or more drugs, and able to safely degrade in the body or be excreted with human metabolism is very important. Summary of the Invention

[0007] (1) Technical problems solved

[0008] In response to the shortcomings of the existing technology, the present invention provides a soft drug-loaded capsule robot based on magnetic liquid metal and its preparation and driving method, which has the advantages of being able to move under the action of a magnetic field, being able to simultaneously load two drugs and release them at a targeted point.

[0009] (2) Technical solution

[0010] To achieve the above-mentioned object, the present invention provides the following technical solutions: a soft drug-carrying capsule robot based on magnetic liquid metal, comprising: a soft capsule robot body, a soft capsule robot cover, and a degradable sealing sleeve;

[0011] The main body of the soft capsule soft robot includes a fan-shaped magnetic liquid metal storage compartment at the bottom, a fan-shaped drug storage compartment on the left, a rectangular drug release port on the left, a fan-shaped drug storage compartment on the right, and a rectangular drug release port on the right;

[0012] The soft capsule robot body is divided into three equal parts on its axial cross section: a bottom fan-shaped magnetic liquid metal storage compartment, a left fan-shaped drug storage compartment, and a right fan-shaped drug storage compartment. The reverse direction of the center line of the fan-shaped magnetic liquid metal storage compartment at the bottom of the capsule robot is used as the positive direction of the reference axis. The bottoms of the left fan-shaped drug storage compartment and the right fan-shaped drug storage compartment are both angled with the center line, so that the drugs can be released freely under gravity when releasing the drugs.

[0013] The magnetic liquid metal is completely immersed in the electrolyte solution and sealed in the fan-shaped liquid metal storage chamber at the bottom, with no air in the chamber;

[0014] Drug A and drug B are stored in the left fan-shaped drug storage compartment and the right fan-shaped drug storage compartment, respectively. When releasing the drugs, they are released through the left rectangular drug release port and the right rectangular drug release port, respectively.

[0015] Furthermore, the materials of the soft capsule robot body and the soft capsule robot cover are both made of food-grade silica gel (SiO2·nH2O) mixed in a mass ratio of 1:1 between A and B glues. Food-grade silica gel is non-toxic to the human body and is not easily degraded and can be excreted from the body with human metabolism. The material of the magnetic liquid metal is made by mixing rubidium iron boron (NdFeB) magnetic particles and gallium-based liquid metal (EGaIn) in a mass ratio of 1:9, and magnetizing it to enhance the magnetism. The magnetic liquid metal has good fluidity and magnetism, and has a large density. , which can ensure that the fan-shaped magnetic liquid metal storage compartment at the bottom is always at the bottom of the capsule robot when releasing the drug, so as to facilitate the release of the drug with gravity; the electrolyte solution uses dilute hydrochloric acid with a concentration of 1 mol / L, and immersing the magnetic liquid metal in it can ensure that there is no oxide film on the surface of the magnetic liquid metal that affects its fluidity and magnetism; the material of the degradable sealing sleeve is made of edible gelatin, glycerin and water mixed in a mass ratio of 1:5:6. The degradable sealing sleeve is used to seal the left rectangular drug release port and the right rectangular drug release port. It gradually degrades during drug release and will not cause any toxic effects on the human body.

[0016] Furthermore, the preparation method of the capsule robot includes the production of a soft capsule robot body, the production of a soft capsule robot cover, the connection of the soft capsule robot shell, the production of a degradable sealing ring, and the injection of targeted drugs, wherein: the production method of the soft capsule robot body and the soft capsule robot cover is: taking appropriate amounts of food-grade silica gel A and B glue in a mass ratio of 1:1, and then using a stirring rod to fully stir for a time depending on the amount, after stirring, placing in a vacuum machine for defoaming, and then casting them into the capsule robot body mold and the capsule robot cover mold, and demolding after curing to obtain the soft capsule robot shell;

[0017] The preparation method of magnetic liquid metal is as follows: taking an appropriate amount of dilute hydrochloric acid with a concentration of 1 mol / L and placing it in a beaker, using an electronic balance to weigh rubidium iron boron magnetic particles and gallium-based liquid metal in a mass ratio of 1:9, respectively, placing them in the dilute hydrochloric acid, during which the infiltrated liquid metal is kept completely infiltrated by the dilute hydrochloric acid, and then using a stirring rod to stir it thoroughly, and then standing to obtain the magnetic liquid metal;

[0018] The method for making a degradable sealing ring is as follows: take appropriate amounts of edible gelatin, glycerin and water to maintain a mass ratio of 1:5:6, first mix the gelatin and water, let it stand for a while, then add glycerin and mix until the gelatin is thoroughly dispersed, then heat the mixture solution to 80 degrees Celsius, continue mixing until the gelatin is fully dissolved, pour the mixed solution into a degradable sealing ring mold, and demould and remove it after cooling and solidification to obtain a degradable sealing ring;

[0019] The shell connection method of the soft capsule robot is as follows: the prepared capsule robot body is taken out and placed in a shell connection mold, an appropriate amount of magnetic liquid metal is injected into the fan-shaped magnetic liquid metal storage compartment at the bottom, and then the electrolyte solution is injected into the compartment to fill it up, and the soft capsule robot body and the edge of the soft capsule robot cover are connected with food-grade silicone adhesive. After complete bonding, a capsule robot without drug injection is obtained;

[0020] The method for injecting targeted drugs is: place the uninjected capsule robot flat, use a medical syringe to inject an appropriate amount of drug A into the left fan-shaped storage compartment, and similarly, inject drug A or drug B into the right fan-shaped storage compartment, then put the degradable sealing ring into the capsule robot shell to seal it, and obtain a capsule robot filled with one or two drugs.

[0021] A method for driving the magnetic liquid metal soft drug-carrying capsule robot to roll, comprising the following steps:

[0022] The capsule robot's one-side axis is defined as the positive direction of the X-axis, the vertically upward radial direction is defined as the positive direction of the Z-axis, and the direction of the Y-axis is determined according to the right-hand screw rule, thereby establishing a reference coordinate system. By controlling the Helmholtz coil to generate a uniform magnetic field in the positive direction of the Z-axis, the magnetic liquid metal has a high density and is pulled by gravity to the bottom of the capsule robot. At this time, if the Helmholtz coil is controlled to generate a magnetic field of the same magnitude in the positive direction of the Y-axis and the magnetic field on the Z-axis is removed, the magnetic liquid metal in the bottom fan-shaped storage chamber will move in the negative direction of the Y-axis due to the attraction of the magnetic field. Next, the magnetic field on the Y-axis is removed and a magnetic field in the opposite direction of the Z-axis is added. Repeating this process can quickly cause the Helmholtz coil to generate a composite magnetic field that rotates clockwise in the YZ plane. In this case, due to the repulsion of like charges and attraction of opposite charges between the magnetic particles and the external magnetic field, the capsule robot will rotate counterclockwise along the negative direction of the Y-axis in the YZ plane.

[0023] A method for drug release using a magnetic liquid metal-based soft drug-loaded capsule robot, comprising the following steps:

[0024] After the capsule robot reaches the designated location, it adopts two drug release methods: one is rapid drug release, which uses external laser irradiation to heat up and melt the degradable shell, thereby quickly releasing the drug; the other is slow drug release, which uses the digestive effect of gastrointestinal digestive juice to gradually dissolve the degradable shell to achieve sustained release of the drug.

[0025] (3) Beneficial effects

[0026] Compared with the existing technology, the present invention provides a soft drug-carrying capsule robot based on magnetic liquid metal and its preparation and driving method, which has the following beneficial effects:

[0027] 1. This magnetic liquid metal-based soft drug-carrying capsule robot and its preparation and driving method: The shell material of the soft capsule robot body 1 is made of food-grade silicone (SiO2·nH2O) to make the capsule body and cover. It is non-toxic and non-degradable, and can be naturally excreted with human metabolism, avoiding the risk of long-term retention. The magnetic liquid metal is a mixture of gallium-based liquid metal (EGaIn) and rubidium iron boron magnetic powder (NdFeB) in a mass ratio of 1:9, and is completely sealed in the silicone shell, preventing the magnetic particles from directly contacting human tissue and eliminating the hazard of heavy metal residues. Finally, a sealing sleeve is made of edible gelatin / glycerol / water (1:5:6). During drug release, it is degraded by laser or digestive fluid. The product is non-toxic and can be absorbed or metabolized by the human body.

[0028] 2. The soft drug-loaded capsule robot based on magnetic liquid metal and its preparation and driving method, the capsule body adopts a three-part fan-shaped chamber structure (liquid metal chamber + double drug chamber). The bottom liquid metal chamber is always located at the bottom of the capsule due to its high density and is affected by gravity, ensuring that the drug can be stably released from the rectangular drug release port (size 8mm×3mm) by gravity during drug release; the liquid metal is immersed in a 1mol / L dilute hydrochloric acid electrolyte solution to maintain the surface free of oxide film, ensuring fluidity and magnetic response stability, and ultimately abandoning the traditional capsule robot's hard components such as batteries and motors, and is only driven by an external magnetic field to avoid the risk of failure caused by internal mechanical failure.

[0029] 3. The magnetic liquid metal-based soft drug-loaded capsule robot and its preparation and driving method use Helmholtz coils to generate a clockwise rotating composite magnetic field in the YZ plane, and the magnetic response of the magnetic liquid metal enables the capsule to roll counterclockwise. External magnetic field drive solves the problem of limited energy supply for the micro-robot, and supports movement in any direction and precise positioning. External laser irradiation is used to melt the gelatin sealing sleeve to achieve instantaneous drug release (suitable for emergency treatment). The sealing sleeve is gradually dissolved by gastrointestinal digestive fluid to achieve slow drug release (suitable for chronic disease treatment). The dual drug chamber design supports sequential drug release, and the release of single drugs or dual drugs can be flexibly selected according to treatment needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic structural diagram of the magnetic liquid metal-based soft drug-carrying capsule robot of the present invention;

[0031] Figure 2 This is an exploded schematic diagram of a mold for manufacturing the soft capsule robot body of the magnetic liquid metal-based soft drug-carrying capsule robot of the present invention;

[0032] Figure 3 This is a schematic diagram of a mold for manufacturing a soft capsule robot cover of the magnetic liquid metal-based soft drug-carrying capsule robot of the present invention;

[0033] Figure 4 This is a schematic diagram of a mold for manufacturing a degradable sealing ring of the magnetic liquid metal-based soft drug-carrying capsule robot of the present invention;

[0034] Figure 5 This is a schematic diagram of the shell connection method of the magnetic liquid metal-based soft drug-carrying capsule robot of the present invention;

[0035] Figure 6 Schematic diagram of the reference coordinate system of the magnetic liquid metal-based soft drug-carrying capsule robot of the present invention;

[0036] Figure 7 This is a schematic diagram of the rolling motion of the magnetic liquid metal-based soft drug-carrying capsule robot of the present invention;

[0037] Figure 8 Schematic diagram of two drug release modes of the magnetic liquid metal-based soft drug-loaded capsule robot of the present invention;

[0038] Figure 9 This is a schematic diagram of the actual size of the soft drug-carrying capsule robot based on magnetic liquid metal of the present invention.

[0039] In the figure: 1. Soft capsule robot body; 1-1. Fan-shaped magnetic liquid metal storage cabin at the bottom; 1-2. Fan-shaped drug storage cabin on the left; 1-3. Rectangular drug release port on the left; 1-4. Fan-shaped drug storage cabin on the right; 1-5. Rectangular drug release port on the right; 2. Soft capsule robot cover; 3. Degradable sealing sleeve; 4. Capsule robot body mold; 5. Capsule robot cover mold; 6. Degradable sealing ring mold. DETAILED DESCRIPTION

[0040] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0041] See also Figure 1-9 , a soft drug-carrying capsule robot based on magnetic liquid metal, comprising: a soft capsule robot body 1, a soft capsule robot cover 2, and a degradable sealing sleeve 3;

[0042] The main body 1 of the soft capsule soft robot includes a bottom fan-shaped magnetic liquid metal storage chamber 1-1, a left fan-shaped drug storage chamber 1-2, a left rectangular drug release port 1-3, a right fan-shaped drug storage chamber 1-4, and a right rectangular drug release port 1-5;

[0043] The main body 1 of the soft capsule robot is divided into three equal parts on its axial cross section: a bottom fan-shaped magnetic liquid metal storage cabin 1-1, a left fan-shaped drug storage cabin 1-2, and a right fan-shaped drug storage cabin 1-4. The opposite direction of the center line of the fan-shaped magnetic liquid metal storage cabin 1-1 at the bottom of the capsule robot is used as the positive direction of the reference axis. The bottoms of the left fan-shaped drug storage cabin 1-2 and the right fan-shaped drug storage cabin 1-4 are both at a 120-degree angle to the center line, so that the drugs can be released freely under gravity when releasing them.

[0044] The magnetic liquid metal is completely immersed in the electrolyte solution and sealed together in the fan-shaped liquid metal storage chamber 1-1 at the bottom, with no air in the chamber;

[0045] Drug A and drug B are stored in the left fan-shaped drug storage compartment 1-2 and the right fan-shaped drug storage compartment 1-4, respectively. When releasing the drugs, they are released through the left rectangular drug release port 1-3 and the right rectangular drug release port 1-5, respectively.

[0046] A method for driving the magnetic liquid metal soft drug-carrying capsule robot as described above to roll, comprising the following specific steps:

[0047] The capsule robot's one-side axis is defined as the positive direction of the X-axis, the vertically upward radial direction is defined as the positive direction of the Z-axis, and the direction of the Y-axis is determined according to the right-hand screw rule, thereby establishing a reference coordinate system. By controlling the Helmholtz coil to generate a uniform magnetic field in the positive direction of the Z-axis, the magnetic liquid metal has a high density and is pulled by gravity to the bottom of the capsule robot. At this time, if the Helmholtz coil is controlled to generate a magnetic field of the same magnitude in the positive direction of the Y-axis and the magnetic field on the Z-axis is removed, the magnetic liquid metal in the bottom fan-shaped storage chamber will move in the negative direction of the Y-axis due to the attraction of the magnetic field. Next, the magnetic field on the Y-axis is removed and a magnetic field in the opposite direction of the Z-axis is added. Repeating this process can quickly cause the Helmholtz coil to generate a composite magnetic field that rotates clockwise in the YZ plane. In this case, due to the repulsion of like charges and attraction of opposite charges between the magnetic particles and the external magnetic field, the capsule robot will rotate counterclockwise along the negative direction of the Y-axis in the YZ plane.

[0048] A method for drug release using a magnetic liquid metal-based soft drug-loaded capsule robot, comprising the following steps:

[0049] After the capsule robot reaches the designated location, it adopts two drug release methods: one is rapid drug release, which uses external laser irradiation to heat up and melt the degradable shell, thereby quickly releasing the drug; the other is slow drug release, which uses the digestive effect of gastrointestinal digestive juice to gradually dissolve the degradable shell to achieve sustained release of the drug.

[0050] In the examples:

[0051] (1) Figure 9 As shown, the overall diameter of the soft capsule robot shell of the soft drug-loaded capsule robot based on magnetic liquid metal is 6 mm, the thickness is 0.5 mm, and the length is 27 mm.

[0052] (2) The main body 1 of the soft capsule soft robot includes a bottom fan-shaped magnetic liquid metal storage chamber 1-1, a left fan-shaped drug storage chamber 1-2, a left rectangular drug release port 1-3, a right fan-shaped drug storage chamber 1-4, and a right rectangular drug release port 1-5. The cross section on the YZ plane is a circle divided into three equal parts. The spacing between each fan-shaped storage chamber is 0.5 mm. The radius of the bottom fan-shaped magnetic liquid metal chamber 1-1 is 4.7 mm, and the angle is 120 degrees. The thickness of the left rectangular drug release port 1-3 and the right rectangular drug release port 1-5 is 0.5 mm, the length is 8 mm, and the width is 3 mm. The degradable sealing sleeve 3 has an inner diameter of 6 mm and a thickness of 0.3 mm.

[0053] (3) The various components of the soft drug-carrying capsule robot based on magnetic liquid metal are made of different materials. Specifically, the materials of the soft capsule robot body 1 and the soft capsule robot cover 2 are made of food-grade silica gel (SiO2·nH2O) mixed in a mass ratio of 1:1 between A and B glue. Food-grade silica gel is non-toxic to the human body and is not easily degraded and can be excreted from the body with human metabolism; the material of the magnetic liquid metal is made by mixing rubidium iron boron (NdFeB) magnetic particles and gallium-based liquid metal (EGaIn) in a mass ratio of 1:9, and magnetizing it to enhance the magnetism. The magnetic liquid metal has good fluidity and magnetism, and it has a large density, which can ensure that when releasing the drug, the bottom fan-shaped magnetic liquid metal storage compartment 1-1 is always at the bottom of the capsule robot, so that the drug can be discharged with the weight. release of force; the electrolyte solution uses dilute hydrochloric acid with a concentration of 1 mol / L, and immersing the magnetic liquid metal in it can ensure that there is no oxide film on the surface of the magnetic liquid metal that affects its fluidity and magnetism; the material of the degradable sealing sleeve 3 is made of edible gelatin, glycerin and water with a mass ratio of 1:5:6. The degradable sealing sleeve is used to seal the left rectangular drug release port 1-3 and the right rectangular drug release port 1-5, and gradually degrades during drug release without causing any toxic effects on the human body. Micron-level guide grooves (width 50-100 μm, depth 20 μm) are added to the inner walls of the left rectangular drug release port 1-3 and the right rectangular drug release port 1-5 to prevent high-viscosity drugs from sticking, and the left rectangular drug release port 1-3 and the right rectangular drug release port 1-5 are located at the bottom edge of their respective fan-shaped compartments to ensure that the drugs can be completely emptied under the action of gravity.

[0054] (4) The preparation method of the soft drug-carrying capsule robot is as follows:

[0055] Step 1: Mold making:

[0056] like Figure 2 、 3 As shown in ,4, two-photon polymerization 3D printing is used to make the mold, with a surface roughness Ra ≤ 0.8 μm, and a 0.2 mm nozzle is used to make the molds of the various components of the capsule robot;

[0057] Step 2: Production of the soft capsule robot body and soft capsule robot cover:

[0058] Take appropriate amounts of food-grade silicone glue A and B and mix them in a mass ratio of 1:1. Then use a stirring rod to stir thoroughly for a time depending on the amount. After stirring, place it in a vacuum machine to remove bubbles. Then, pour it into the capsule robot main body mold 4 and the capsule robot cover mold 5 respectively. After curing, demould it to obtain the soft capsule robot shell.

[0059] Step 3: Preparation of magnetic liquid metal:

[0060] Take an appropriate amount of dilute hydrochloric acid with a concentration of 1 mol / L and place it in a beaker. Use an electronic balance to weigh rubidium iron boron magnetic particles and gallium-based liquid metal with a mass ratio of 1:9, respectively, and place them in the dilute hydrochloric acid respectively. During the period, keep the infiltrated liquid metal completely infiltrated by the dilute hydrochloric acid, then use a stirring rod to stir it thoroughly, and then stand to obtain magnetic liquid metal.

[0061] Step 4: Making the biodegradable sealing ring:

[0062] Take appropriate amounts of edible gelatin, glycerin and water to maintain a mass ratio of 1:5:6. First mix the gelatin and water, let it stand for a while, then add glycerin and mix until the gelatin is thoroughly dispersed. Then heat the mixture solution to 80 degrees Celsius and continue mixing until the gelatin is fully dissolved. Pour the mixed solution into the degradable sealing ring mold 6, and demold it after cooling and solidification to obtain a degradable sealing ring.

[0063] Step 5. Connect the soft capsule robot shell:

[0064] like Figure 5 As shown, the prepared capsule robot body is taken out and placed in the shell connection mold. An appropriate amount of magnetic liquid metal (in syringe A) is injected into the fan-shaped magnetic liquid metal storage compartment at the bottom, and then the electrolyte solution (in syringe B) is injected into it to fill it up. The soft capsule robot body and the edge of the soft capsule robot cover (white ring) are connected with food-grade silicone adhesive (in the beaker). After complete bonding, the capsule robot without drug injection is obtained, and the fan-shaped liquid metal compartment (density ≥6.5g / cm 3 ) and drug cabin (density ≈ 1g / cm 3 ) density difference design ensures that the liquid metal cabin is always at the bottom in the direction of gravity in any body position.

[0065] Step 6: Injection of targeted drugs:

[0066] Place the unmedicated capsule robot flat, and use a medical syringe to inject an appropriate amount of drug A into the left fan-shaped storage compartment. Similarly, inject drug A or drug B into the right fan-shaped storage compartment, and then put the degradable sealing ring into the capsule robot shell to seal it, to obtain a capsule robot filled with one or two drugs.

[0067] (5) The method for the soft drug-loaded capsule robot to achieve rolling motion, specifically,

[0068] like Figure 6 、 7 As shown in the figure, the axial direction of one side of the capsule robot is defined as the positive direction of the X-axis, the vertical upward radial direction is defined as the positive direction of the Z-axis, and the direction of the Y-axis is determined according to the right-hand screw rule, thereby forming a reference coordinate system; by controlling the Helmholtz coil to generate a uniform magnetic field in the positive direction of the Z-axis, due to the large density of the magnetic liquid metal, the bottom fan-shaped magnetic liquid metal storage chamber will be located at the bottom of the capsule robot under the action of gravity; at this time, if the Helmholtz coil is controlled to generate a magnetic field of the same magnitude in the positive direction of the Y-axis and the magnetic field on the Z-axis is removed, the magnetic liquid metal in the bottom fan-shaped storage chamber will move toward the negative direction of the Y-axis due to the attraction of the magnetic field; then, the magnetic field on the Y-axis is removed and a magnetic field in the opposite direction of the Z-axis is added at the same time. Repeating this process can quickly cause the Helmholtz coil to generate a composite magnetic field rotating clockwise in the YZ plane; in this case, due to the repulsion of like charges and attraction of opposite charges between the magnetic particles and the external magnetic field, the capsule robot will rotate counterclockwise along the negative direction of the Y-axis in the YZ plane.

[0069] (6) The method for the soft drug-carrying capsule robot to release the drug, specifically, Figure 8 As shown, after the capsule robot reaches the designated position, it adopts two drug release methods: one is rapid drug release, which uses external laser irradiation to heat up and melt the degradable shell, thereby quickly releasing the drug; the other is slow drug release, which uses the digestive effect of gastrointestinal digestive juice to gradually dissolve the degradable shell to achieve sustained release of the drug.

[0070] In summary, the soft drug-loaded capsule robot based on magnetic liquid metal and its preparation and driving method are as follows: the shell material of the soft capsule robot body 1 is set to food-grade silicone (SiO2·nH2O) to make the capsule body and cover, which is non-toxic and non-degradable, and can be naturally excreted with human metabolism to avoid the risk of long-term retention; at the same time, a nano-breathable membrane (pore size 0.22μm) is set in the cover to allow gas exchange but block liquid seepage, so as to keep the inside and outside of the soft capsule robot body 1 in a pressure balance state; and the magnetic liquid metal is a mixture of gallium-based liquid metal (EGaIn) and rubidium iron boron magnetic powder (NdFeB) in a mass ratio of 1:9, and is completely sealed in the silicone shell, so as to prevent the magnetic particles from directly contacting human tissue and eliminate the hazards of heavy metal residues; finally, a sealing sleeve is made of edible gelatin / glycerol / water (1:5:6), which is degraded by laser or digestive fluid during drug release, and the product is non-toxic and can be absorbed or metabolized by the human body.

[0071] In addition, the capsule body adopts a three-part fan-shaped chamber structure (liquid metal chamber + double drug chamber). The bottom liquid metal chamber is always located at the bottom of the capsule due to its high density and is affected by gravity, ensuring that the drug can be stably released from the rectangular drug release port (size 8mm×3mm) by gravity during drug release; the liquid metal is immersed in a 1mol / L dilute hydrochloric acid electrolyte solution to maintain a surface free of oxide film, ensuring fluidity and magnetic response stability, and ultimately abandoning the traditional capsule robot's hard components such as batteries and motors, and is only driven by an external magnetic field to avoid the risk of failure caused by internal mechanical failure.

[0072] In addition, a Helmholtz coil is used to generate a clockwise rotating composite magnetic field in the YZ plane, and the counterclockwise rolling of the capsule is achieved through the magnetic response of the magnetic liquid metal; the problem of limited energy supply of the microrobot is solved by external magnetic field drive, and it supports movement in any direction and precise positioning; the gelatin sealing sleeve is melted by external laser irradiation to achieve instantaneous drug release (suitable for emergency treatment); the sealing sleeve is gradually dissolved by gastrointestinal digestive juice to achieve slow drug release (suitable for chronic disease treatment); the dual drug chamber design supports sequential drug release, and single drug or dual drug combination release can be flexibly selected according to treatment needs.

[0073] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0074] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A soft drug-carrying capsule robot based on magnetic liquid metal, characterized in that: include: A soft capsule robot body (1), a soft capsule robot cover (2), and a degradable sealing sleeve (3); The soft capsule soft robot body (1) comprises a bottom fan-shaped magnetic liquid metal storage chamber (1-1), a left fan-shaped drug storage chamber (1-2), a left rectangular drug release port (1-3), a right fan-shaped drug storage chamber (1-4), and a right rectangular drug release port (1-5); The soft capsule robot body (1) is divided into three equal parts on its axial cross section: a bottom fan-shaped magnetic liquid metal storage cabin (1-1), a left fan-shaped medicine storage cabin (1-2), and a right fan-shaped medicine storage cabin (1-4). The reverse direction of the center line of the fan-shaped magnetic liquid metal storage cabin (1-1) at the bottom of the capsule robot is used as the positive direction of the reference axis. The bottoms of the left fan-shaped medicine storage cabin (1-2) and the right fan-shaped medicine storage cabin (1-4) are both at an angle of 120 degrees to the center line, so that the medicine can be released freely under gravity when releasing the medicine. The magnetic liquid metal is completely immersed in the electrolyte solution and sealed together in the fan-shaped liquid metal storage chamber (1-1) at the bottom, with no air in the chamber; Drug A and drug B are stored in the left fan-shaped drug storage compartment (1-2) and the right fan-shaped drug storage compartment (1-4), respectively. When releasing the drugs, they are released through the left rectangular drug release port (1-3) and the right rectangular drug release port (1-5), respectively.

2. The magnetic liquid metal-based soft drug-carrying capsule robot according to claim 1, characterized in that: The materials of the soft capsule robot body (1) and the soft capsule robot cover (2) are both made of food-grade silica gel (SiO2·nH2O) mixed in a mass ratio of 1:1 between A and B. The food-grade silica gel is non-toxic to the human body and is not easily degraded and can be excreted from the body with human metabolism. The material of the magnetic liquid metal is made by mixing rubidium iron boron (NdFeB) magnetic particles and gallium-based liquid metal (EGaIn) in a mass ratio of 1:9, and magnetizing the mixture to enhance magnetic properties. The magnetic liquid metal has good fluidity and magnetic properties, and has a large density, which can ensure that the drug is released. The fan-shaped magnetic liquid metal storage cabin (1-1) at the bottom is always at the bottom of the capsule robot to facilitate the release of drugs with gravity; the electrolyte solution uses dilute hydrochloric acid with a concentration of 1 mol / L, and the magnetic liquid metal is immersed in it to ensure that there is no oxide film on the surface of the magnetic liquid metal that affects its fluidity and magnetism; the material of the degradable sealing sleeve (3) is made of edible gelatin, glycerin and water with a mass ratio of 1:5:

6. The degradable sealing sleeve is used to seal the left rectangular drug release port (1-3) and the right rectangular drug release port (1-5). It gradually degrades when releasing drugs and will not cause any toxic effects on the human body.

3. The magnetic liquid metal-based soft drug-carrying capsule robot according to claim 1, characterized in that: The preparation method of the capsule robot includes the following steps: making a soft capsule robot body, making a soft capsule robot cover, connecting a soft capsule robot shell, making a degradable sealing ring, and injecting a targeted drug, wherein: the preparation method of the soft capsule robot body and the soft capsule robot cover is as follows: taking appropriate amounts of food-grade silica gel A and B glue and mixing them in a mass ratio of 1:1, then using a stirring rod to fully stir for a time depending on the amount, after stirring, placing the mixture in a vacuum machine for defoaming, and then casting the mixture into a capsule robot body mold (4) and a capsule robot cover mold (5), and demoulding the mixture after solidification to obtain a soft capsule robot shell; The preparation method of magnetic liquid metal is as follows: taking an appropriate amount of dilute hydrochloric acid with a concentration of 1 mol / L and placing it in a beaker, using an electronic balance to weigh rubidium iron boron magnetic particles and gallium-based liquid metal in a mass ratio of 1:9, respectively, placing them in the dilute hydrochloric acid, during which the infiltrated liquid metal is kept completely infiltrated by the dilute hydrochloric acid, and then using a stirring rod to stir it thoroughly, and then standing to obtain the magnetic liquid metal; The method for making a degradable sealing ring is as follows: taking appropriate amounts of edible gelatin, glycerin and water so as to maintain a mass ratio of 1:5:6, first mixing the gelatin and water, letting them stand for a while, then adding glycerin and mixing until the gelatin is thoroughly dispersed, then heating the mixture solution to 80 degrees Celsius, continuing to mix until the gelatin is fully dissolved, pouring the mixed solution into a degradable sealing ring mold (6), and demoulding and removing it after cooling and solidification to obtain a degradable sealing ring; The shell connection method of the soft capsule robot is as follows: the prepared capsule robot body is taken out and placed in a shell connection mold, an appropriate amount of magnetic liquid metal is injected into the fan-shaped magnetic liquid metal storage compartment at the bottom, and then the electrolyte solution is injected into the compartment to fill it up, and the soft capsule robot body and the edge of the soft capsule robot cover are connected with food-grade silicone adhesive. After complete bonding, a capsule robot without drug injection is obtained; The method for injecting targeted drugs is: place the uninjected capsule robot flat, use a medical syringe to inject an appropriate amount of drug A into the left fan-shaped storage compartment, and similarly, inject drug A or drug B into the right fan-shaped storage compartment, then put the degradable sealing ring into the capsule robot shell to seal it, and obtain a capsule robot filled with one or two drugs.

4. A method for driving the magnetic liquid metal soft drug-loaded capsule robot as claimed in claim 1 to achieve rolling, characterized in that: The specific steps are: The capsule robot's one-side axis is defined as the positive direction of the X-axis, the vertically upward radial direction is defined as the positive direction of the Z-axis, and the direction of the Y-axis is determined according to the right-hand screw rule, thereby establishing a reference coordinate system. By controlling the Helmholtz coil to generate a uniform magnetic field in the positive direction of the Z-axis, the magnetic liquid metal has a high density and is pulled by gravity to the bottom of the capsule robot. At this time, if the Helmholtz coil is controlled to generate a magnetic field of the same magnitude in the positive direction of the Y-axis and the magnetic field on the Z-axis is removed, the magnetic liquid metal in the bottom fan-shaped storage chamber will move in the negative direction of the Y-axis due to the attraction of the magnetic field. Next, the magnetic field on the Y-axis is removed and a magnetic field in the opposite direction of the Z-axis is added. Repeating this process can quickly cause the Helmholtz coil to generate a composite magnetic field that rotates clockwise in the YZ plane. In this case, due to the repulsion of like charges and attraction of opposite charges between the magnetic particles and the external magnetic field, the capsule robot will rotate counterclockwise along the negative direction of the Y-axis in the YZ plane.

5. The method for drug release by a magnetic liquid metal-based soft drug-loaded capsule robot according to claim 1, characterized in that: The specific steps are: After the capsule robot reaches the designated location, it adopts two drug release methods: one is rapid drug release, which uses external laser irradiation to heat up and melt the degradable shell, thereby quickly releasing the drug; the other is slow drug release, which uses the digestive effect of gastrointestinal digestive juice to gradually dissolve the degradable shell to achieve sustained release of the drug.

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