A shape memory microrobot for removing blood clots

Abstract

The present invention relates to the field of micro-robot technology, and in particular to a shape memory micro-robot for removing blood clots. An embodiment of the present invention provides a shape memory micro-robot for removing blood clots, comprising a shell having an internal space and a magnet disposed in the shell and having magnetic properties; the shell is made of a shape memory material, a through hole is disposed on the shell, the shell comprises a contracted state and an expanded state, and the internal space of the shell in the expanded state is larger than the internal space in the contracted state. An embodiment of the present invention provides a shape memory micro-robot for removing blood clots, which can prevent doctors from being exposed to radiation during surgery.

Description

Technical Field

[0001] The present invention relates to the technical field of microrobots, and in particular to a shape memory microrobot for removing thrombus. Background Art

[0002] Blood clots are a common disease.

[0003] Currently, the common method of treating thrombosis includes catheter embolectomy. However, catheter embolectomy requires doctors to perform the operation under X-rays, and the accumulation of X-ray radiation will cause certain damage to the doctor's health.

[0004] Therefore, in view of the above shortcomings, it is necessary to provide a shape memory microrobot for removing thrombus. Summary of the invention

[0005] The embodiment of the present invention provides a shape memory microrobot for removing blood clots, which can prevent doctors from being exposed to radiation during surgery.

[0006] An embodiment of the present invention provides a shape memory microrobot for removing thrombus, comprising a shell having an internal space and a magnet disposed in the shell and having magnetic properties;

[0007] The shell is made of a shape memory material. A through hole is provided on the shell. The shell includes a contracted state and an expanded state. The internal space of the shell in the expanded state is larger than the internal space in the contracted state.

[0008] In a possible design, the shell in the expanded state is pyramid-shaped, and the surface of the shell in the expanded state is recessed inwardly or folded and deformed into a contracted state with a pointed end.

[0009] In a possible design, the area of ​​the bottom surface of the shell in the expanded state is smaller than the area of ​​the side surface, and the bottom surface does not have the through hole.

[0010] In one possible design, the shape memory material includes a biocompatible shape memory polymer.

[0011] In a possible design, the shape memory material includes at least one of polylactic acid, polyetheretherketone, polyurethane, polycaprolactone, polylactic acid-caprolactone copolymer and polymethyl methacrylate.

[0012] In a possible design, the magnet includes a plurality of magnetic particles, and the plurality of magnetic particles are uniformly distributed in the shell.

[0013] In a possible design, the material used to prepare the magnet includes magnetic particles having biocompatibility and photothermal effect.

[0014] In a possible design, the preparation material of the magnet includes at least one of nickel-iron nanoparticles, titanium dioxide-coated iron oxide magnetic nanoparticles, iron oxide nanoparticles, manganese oxide nanocrystals and iron porphyrin magnetic nanoparticles.

[0015] In a possible design, the shell is deformed from a contracted state to an expanded state by irradiation with near-infrared light.

[0016] Compared with the prior art, the present invention has at least the following beneficial effects:

[0017] In this embodiment, in order to facilitate the free movement of the microrobot in the blood vessel, the size of the microrobot is in the micrometer and nanometer levels. When it is necessary to remove the thrombus, the shell in the contracted state is placed in the blood vessel. A magnet is arranged in the shell. The shell is controlled to move in the blood vessel by an externally applied magnetic field, so that the shell enters the thrombus. Then a deformation stimulus is applied to the shell, so that the shell is deformed from a contracted state with a smaller internal space to an expanded state with a larger internal space. During the expansion process, the thrombus outside the shell is sucked into the shell through the through hole. Finally, the shell carrying the thrombus is taken out of the blood vessel by an external magnetic field to complete the thrombus cleaning. After entering the blood vessel, the microrobot can load and carry the thrombus by remote operation, which can effectively avoid the risk of long-term exposure of medical staff to radiation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 is a schematic diagram of a top view of a shape memory micro robot in an unfolded state provided by an embodiment of the present invention;

[0020] Figure 2 This is a schematic diagram of the main structure of a shape memory micro robot in an unfolded state provided by an embodiment of the present invention;

[0021] Figure 3 is a schematic diagram of the structure of a shape memory micro robot in an unfolded state provided by an embodiment of the present invention, viewed from above;

[0022] Figure 4 is a schematic cross-sectional structure diagram of a shape memory microrobot in an unfolded state provided by an embodiment of the present invention;

[0023] Figure 5is a schematic diagram of a top view of a shape memory microrobot in a contracted state provided by an embodiment of the present invention;

[0024] Figure 6 This is a schematic diagram of the main structure of a shape memory micro robot in an unfolded state provided by an embodiment of the present invention;

[0025] Figure 7 is a schematic diagram of the structure of a shape memory micro robot in an unfolded state provided by an embodiment of the present invention, viewed from above;

[0026] Figure 8 It is a schematic diagram of a method for using a shape memory micro robot provided by an embodiment of the present invention.

[0027] In the figure:

[0028] 1- housing;

[0029] 2-Through hole;

[0030] 3-Bottom;

[0031] 4- Magnetic particles;

[0032] 5-catheter;

[0033] 6-blood vessels;

[0034] 7-Thrombosis. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0036] In the description of the embodiments of the present invention, unless otherwise clearly specified and limited, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance; unless otherwise specified or explained, the term "multiple" refers to two or more; the terms "connected" and "fixed" should be understood in a broad sense, for example, "connected" can be a fixed connection, a detachable connection, an integral connection, or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] In the description of this specification, it should be understood that the directional words such as "upper" and "lower" described in the embodiments of the present invention are described at the angles shown in the drawings and should not be understood as limiting the embodiments of the present invention. In addition, in the context, it should also be understood that when it is mentioned that an element is connected to another element "upper" or "lower", it can not only be directly connected to another element "upper" or "lower", but also indirectly connected to another element "upper" or "lower" through an intermediate element.

[0038] like Figures 1 to 7 As shown, an embodiment of the present invention provides a shape memory microrobot for removing thrombus 7, comprising a shell 1 having an internal space and a magnet disposed in the shell 1 and having magnetic properties;

[0039] The shell 1 is made of a shape memory material. A through hole 2 is provided on the shell 1. The shell 1 includes a contracted state and an expanded state. The internal space of the shell 1 in the expanded state is larger than the internal space in the contracted state.

[0040] In this embodiment, in order to facilitate the free movement of the microrobot in the blood vessel 6, the size of the microrobot is in the micrometer or nanometer level. When the thrombus 7 needs to be removed, the shell 1 in the contracted state is placed in the blood vessel 6. A magnet is arranged in the shell 1. The shell 1 is controlled to move in the blood vessel 6 by an externally applied magnetic field, so that the shell 1 enters the thrombus 7. Then, a deformation stimulus is applied to the shell 1, so that the shell 1 is deformed from the contracted state with a smaller internal space to the expanded state with a larger internal space. During the expansion process, the thrombus 7 outside the shell 1 is sucked into the shell 1 through the through hole 2. Finally, the shell 1 carrying the thrombus 7 is taken out of the blood vessel 6 by the external magnetic field to complete the thrombus 7 cleaning. After entering the blood vessel 6, the microrobot can load and carry the thrombus 7 by remote operation, which can effectively avoid the risk of long-term exposure of medical staff to radiation.

[0041] It is understandable that, due to the small size of the microrobot, multiple microrobots can be introduced into the thrombus 7 each time the thrombus 7 is cleaned to improve efficiency. Multiple through holes 2 can be provided to facilitate the thrombus 7 to enter the interior of the housing 1 during the deformation process.

[0042] In some embodiments of the present invention, the housing 1 in the unfolded state is in the shape of a pyramid, and in the unfolded state, the surface of the housing 1 is formed to be concave inwardly thereof or folded and deformed into a contracted state with a pointed end.

[0043] In this embodiment, both the expanded state and the contracted state have a pointed end, which facilitates the housing 1 to move in and out of the thrombus 7 .

[0044] In some embodiments of the present invention, the area of ​​the bottom surface 3 of the housing 1 in the unfolded state is smaller than the area of ​​the side surface, and the bottom surface 3 has no through hole 2 .

[0045] In this embodiment, in order to prevent the thrombus 7 from falling off during the process of the housing 1 carrying the thrombus 7 removing the blood vessel 6, the bottom surface 3 of the housing 1 in the expanded state is not provided with the through hole 2. Specifically, since the area of ​​the bottom surface 3 of the pyramid is the smallest, the resistance is the smallest when the bottom surface 3 faces the opposite direction of the movement during the movement, which is similar to the unidirectional movement of a rocket. Therefore, setting the bottom surface 3 to a non-porous structure can prevent the thrombus 7 from falling off during the movement.

[0046] In some embodiments of the present invention, the shape memory material comprises a biocompatible shape memory polymer.

[0047] In this embodiment, the biocompatible shape memory polymer has no toxic side effects on the human body and will not damage the inner wall of the blood vessel 6 during exercise. Of course, shape memory metals can also be used, but shape memory polymers have lower density and stronger deformation ability than shape memory metals.

[0048] In some embodiments of the present invention, the shape memory material includes at least one of polylactic acid, polyetheretherketone, polyurethane, polycaprolactone, polylactic acid-caprolactone copolymer and polymethyl methacrylate.

[0049] In this embodiment, the shape memory polymers are all biocompatible shape memory polymers.

[0050] It should be noted that the initial shape of the shell 1 is in the expanded state. Before entering the human body, the shell 1 is heated to above the glass transition temperature Tg, and a load is applied to compress the internal cavity and make the head more pointed, so that the deformed structure is easier to enter the thrombus 7. Then, while maintaining the load, the temperature is lowered to below Tg, and the shell 1 maintains the contracted shape without deformation. After the magnetic field controls the shell 1 to enter the thrombus 7, a stimulus is applied to raise the temperature of the shell 1 to above Tg, so that the shell 1 changes to the expanded state.

[0051] In some embodiments of the present invention, the magnet includes a plurality of magnetic particles 4 , and the plurality of magnetic particles 4 are uniformly distributed in the shell 1 .

[0052] In this embodiment, a plurality of magnetic particles 4 are evenly distributed in the shell 1 to facilitate the stable movement of the shell 1 controlled by the magnetic field.

[0053] In some embodiments of the present invention, the material used to prepare the magnet includes magnetic particles 4 having biocompatibility and photothermal effect.

[0054] In this embodiment, the magnet is biocompatible and will not produce any toxic side effects when entering the human body. At the same time, it also has a photothermal effect. By applying light waves to the magnet, it can heat up, thereby causing the shell 1 to heat up and deform.

[0055] In some embodiments of the present invention, the material used to prepare the magnet includes at least one of nickel-iron nanoparticles, titanium dioxide-coated iron oxide magnetic nanoparticles, iron oxide nanoparticles, manganese oxide nanocrystals and iron porphyrin magnetic nanoparticles.

[0056] In this embodiment, the above materials are all magnetic particles 4 having biocompatibility and photothermal effect.

[0057] In some embodiments of the present invention, the housing 1 is deformed from a contracted state to an expanded state by near-infrared light irradiation.

[0058] In this embodiment, the near-infrared light will only cause the magnet with the photothermal effect to heat up rapidly, and will not have a significant impact on the human body.

[0059] In order to more clearly illustrate the micro robot provided by the present application, Figure 8 As shown, the embodiment of the present invention also provides a method for using a micro robot, and the specific steps are as follows:

[0060] The patient is placed under the MRI machine, and then the Helmholtz coil of the MRI system is used to generate a uniform magnetic field to control the movement of the micro-nano robot in the blood vessel 6. Since the shell of the micro-nano robot has uniformly distributed magnetic particles 4, it can move to the thrombus 7 in a directional manner along the magnetic field direction under the action of the magnetic field, and enter the interior of the thrombus 7 under the action of the magnetic field.

[0061] Furthermore, the initial shape of the micro-nano robot is a triangular pyramid, and the micro-nano robot structure is deformed by certain stimulation to achieve the effect of treating thrombus 7.

[0062] Furthermore, the stimulation method is to change the temperature, by heating it above Tg, applying a load so that the internal cavity of the robot is compressed and the head becomes sharper, so that the deformed structure is easier to enter the interior of the thrombus 7

[0063] Furthermore, the temperature is lowered to below Tg while maintaining the load. At this time, the micro-nano robot maintains its shape without deformation, which is a temporary state.

[0064] Furthermore, the catheter 5 is implanted into the blood vessel 6 containing the thrombus 7 , and then the micro-nano robot with a temporary shape is transported to the interior of the blood vessel 6 using the catheter 5 .

[0065] Furthermore, after the micro-nano robot enters the interior of the thrombus 7, near-infrared light is used to irradiate the micro-nano robot. Since the magnetic particles 4 inside the robot have photothermal function, the micro-nano robot can be heated up to above Tg again under the irradiation of near-infrared light, thereby realizing the shape memory function.

[0066] Furthermore, the near-infrared light has a wavelength of 808 nm.

[0067] Furthermore, the volume of the internal cavity of the micro-nano robot becomes larger. Since the shell surface of the micro-nano robot has a porous structure, the thrombus 7 will be sucked into the internal cavity of the micro-nano robot when the micro-nano robot returns to its original shape.

[0068] Furthermore, a magnetic field is applied to the robot again, so that the robot carrying the thrombus 7 moves again along the direction of the magnetic field back to the inside of the catheter 5 and leaves the blood vessel 6.

[0069] Furthermore, since the bottom layer of the micro-nano robot is a solid structure, the bottom layer will provide a certain support force to the thrombus 7 during the transportation of the thrombus 7, and the thrombus 7 will not overflow from the cavity of the robot.

[0070] Furthermore, the thrombus 7 in the blood vessel 6 can be cleared by repeating the above operation several times.

[0071] According to the method for using the micro-nano robot provided by the present invention, the beneficial effects achieved by adopting the above technical scheme are: compared with the traditional catheter 5 thrombectomy, this method does not need to insert the catheter 5 deep into the blood vessel 6, but only needs to fix the catheter 5 at the opening of the blood vessel 6, thereby avoiding the friction between the catheter 5 and the blood vessel 6 during the movement inside the blood vessel 6, thereby avoiding damage to the wall of the blood vessel 6; the shell of the micro-nano robot is made of shape memory polymer, and due to the smooth surface of the shell, it will not cause damage to the inner wall of the blood vessel 6; the magnetic field's control of the robot's movement direction can effectively prevent the thrombus 7 from falling off during the transportation of the thrombus 7 by the robot carrying the thrombus 7.

[0072] While effectively reducing the risk of thrombus removal surgery, it can also reduce damage to the patient's body. In addition, the use of this micro-nano robot to remove thrombus can effectively prevent medical staff from being exposed to X-ray radiation.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A shape memory microrobot for removing thrombus, characterized in that: The invention comprises a shell having an inner space and a magnet disposed in the shell and having magnetic properties; The shell is made of a shape memory material, a through hole is provided on the shell, the shell includes a contracted state and an expanded state, and the internal space of the shell in the expanded state is larger than the internal space in the contracted state; The shell in the unfolded state is in the shape of a pyramid, and the surface of the shell in the unfolded state is concave inwardly or folded and deformed into a contracted state with a pointed end; The area of ​​the bottom surface of the shell in the unfolded state is smaller than the area of ​​the side surface, and the bottom surface does not have the through hole; The preparation material of the magnet includes magnetic particles with biocompatibility and photothermal effect; The initial shape of the shell is in an expanded state. Before entering the human body, the internal cavity of the shell is compressed and the head of the shell becomes sharper. When the magnetic field controls the shell to enter the thrombus, the shell becomes in an expanded state.

2. The shape memory microrobot according to claim 1, characterized in that: The shape memory material includes a shape memory polymer having biocompatibility.

3. The shape memory microrobot according to claim 1, characterized in that: The shape memory material includes at least one of polylactic acid, polyetheretherketone, polyurethane, polycaprolactone, polylactic acid-caprolactone copolymer and polymethyl methacrylate.

4. The shape memory microrobot according to claim 1, characterized in that: The magnet includes a plurality of magnetic particles, and the plurality of magnetic particles are uniformly distributed in the shell.

5. The shape memory microrobot according to claim 1, characterized in that: The preparation material of the magnet comprises at least one of nickel-iron nanoparticles, titanium dioxide-coated iron oxide magnetic nanoparticles, iron oxide nanoparticles, manganese oxide nanocrystals and iron porphyrin magnetic nanoparticles.

6. The shape memory microrobot according to any one of claims 1 or 5, characterized in that: The shell is deformed from a contracted state to an expanded state by near-infrared light irradiation.

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