阅读说明：本技术 药物缓释型抗肿瘤纳米机器人及其制备方法 (Drug sustained-release anti-tumor nano robot and preparation method thereof ) 是由 不公告发明人 于 2020-11-10 设计创作，主要内容包括：本发明属于纳米材料领域,尤其涉及一种药物缓释型抗肿瘤纳米机器人及其制备方法。本发明提供的制备方法包括以下步骤：将顺磁性金属靶材置于溅射室内,向溅射室内通入氩气和氧气,启动溅射室电源；磁控溅射结束后,先向溅射室内通入乙炔气体,然后通入保护气体,并对溅射室进行快速降温,得到内包顺磁性金属富勒烯颗粒；将内包顺磁性金属富勒烯颗粒、抗肿瘤药物、聚乳酸和挥发性溶剂混合,然后将其与水混合并搅拌挥去混合体系中的挥发性溶剂,离心分离,得到药物缓释型抗肿瘤纳米机器人。本发明提供的制备方法生产工艺稳定,采用该方法制备得到的药物缓释型抗肿瘤纳米机器人具有良好的尺寸均匀性、顺磁性、抗肿瘤功能和药物缓释效果。(The invention belongs to the field of nano materials, and particularly relates to a drug sustained-release anti-tumor nano robot and a preparation method thereof. The preparation method provided by the invention comprises the following steps: placing a paramagnetic metal target material in a sputtering chamber, introducing argon and oxygen into the sputtering chamber, and starting a power supply of the sputtering chamber; after the magnetron sputtering is finished, firstly introducing acetylene gas into the sputtering chamber, then introducing protective gas, and rapidly cooling the sputtering chamber to obtain fullerene particles internally coated with paramagnetic metal; mixing the fullerene particles internally coated with paramagnetic metal, the antitumor drug, the polylactic acid and the volatile solvent, then mixing the fullerene particles with water, stirring the mixture to volatilize the volatile solvent in the mixed system, and performing centrifugal separation to obtain the drug sustained-release antitumor nano robot. The preparation method provided by the invention has a stable production process, and the drug sustained-release anti-tumor nano robot prepared by the method has good size uniformity, paramagnetism, an anti-tumor function and a drug sustained-release effect.)

1. A preparation method of a drug sustained-release anti-tumor nano robot comprises the following steps:

a) placing a paramagnetic metal target material in a sputtering chamber, introducing argon and oxygen into the sputtering chamber, and starting a power supply of the sputtering chamber to perform magnetron sputtering; in the magnetron sputtering process, the temperature of a cavity of the sputtering chamber is 800-1200 ℃;

b) after the magnetron sputtering is finished, maintaining the temperature of a cavity of the sputtering chamber at 800-1200 ℃, and introducing acetylene gas into the sputtering chamber;

c) after the acetylene gas is introduced, introducing protective gas into the sputtering chamber, and reducing the temperature of the cavity of the sputtering chamber to 100-300 ℃ within 5-15 min to obtain the internally-wrapped paramagnetic metal fullerene particles;

d) mixing the paramagnetic metal fullerene particles, the antitumor drug, the polylactic acid and the volatile organic solvent to obtain a mixed solution;

e) mixing the mixed solution with water, stirring and volatilizing the volatile organic solvent in the mixed system to obtain a suspension;

f) and carrying out centrifugal separation on the suspension, and discarding the supernatant to obtain the drug sustained-release anti-tumor nano robot.

2. The method according to claim 1, wherein in step a), the paramagnetic metal target comprises one or more of iron oxide, titanium oxide and zirconium oxide.

3. The preparation method of claim 1, wherein in the step a), during the magnetron sputtering process, the vacuum degree of the sputtering chamber is 10-30 Pa; the gas inflow rate of the argon is 40-50 sccm; the air inflow rate of the oxygen is 10-15 sccm.

4. The manufacturing method according to claim 1, wherein in the step b), the degree of vacuum of the sputtering chamber is 10 to 30 Pa; the gas inflow rate of the acetylene gas is 100-120 sccm.

5. The method according to claim 1, wherein in step c), the particle size of the encapsulated paramagnetic metal fullerene particles is 1 to 100 nm.

6. The method according to claim 1, wherein the antitumor drug in step d) comprises one or more of paclitaxel, dexamethasone, and ranopharyn.

7. The preparation method according to claim 1, wherein in the step d), the mass ratio of the encapsulated paramagnetic metal fullerene particles to the antitumor drug to the polylactic acid is (2-5): (2-5): 1.

8. the method according to claim 1, wherein in step d), the suspension further comprises folic acid and/or a surfactant.

9. The method of claim 8, wherein the surfactant comprises one or more of tween80, tween 20, and a poloxamer.

10. The drug sustained-release anti-tumor nano robot prepared by the preparation method of any one of claims 1 to 9.

Technical Field

The invention belongs to the field of nano materials, and particularly relates to a drug sustained-release anti-tumor nano robot and a preparation method thereof.

Background

Tumor tissue is actually a complete ecosystem formed by tumor cells and tumor blood vessels, and contains not only tumor cells but also abundant tumor blood vessels inside. Modern biomedical research has demonstrated that tumor vessels are structurally very different from normal vessels. In general, normal blood vessels take a year to grow and are three-layer compact structures consisting of intima, media and adventitia, whereas tumor vessels can be formed in only 4 days and are structurally single-layer thin films consisting of endothelial cells. However, because the endothelial cells constituting the tumor vessels have large gaps and incomplete structures, the tumor vessels usually contain a large number of small pores with nanometer scale, so that small molecules and some nanoparticles can pass through the pores.

When the size of the nanoparticles is a proper size (for example, 50-200 nm), it takes several minutes or even several tens of minutes to pass through the gaps of the tumor vessels, and in this process, the nanoparticles are tightly surrounded by the endothelial cells of the tumor vessels, so that the tumor vessels can be specifically destroyed by proper design. Researchers in the chemical institute firstly use magnetic metal fullerene to design water-soluble nanoparticles with the size of about 150 nanometers, and the nanoparticles can improve internal energy through absorbing radio frequency, and have phase change due to the rise of the internal energy after several minutes to dozens of minutes, and the internal energy is accompanied with the violent expansion of the volume by about 50 percent. Then the magnetic metal fullerene nano-particles are injected into the body of the mouse intravenously, and after a few minutes, the nano-particles reach the tumor position and are stuck on the vessel wall for a long time. The mice were then subjected to radio frequency to "detonate" the nanoparticles. Research results show that the magnetic metal fullerene nano-particles embedded on the wall of the tumor vessel are exploded to effectively destroy the tumor vessel, then the nutrition supply to the tumor is rapidly blocked, and the tumor cells can be completely starved within a few hours.

At present, most reported methods for preparing magnetic metal fullerene still stay in the experimental stage, and have the problems of poor stability of the preparation process, poor tumor treatment effect, poor size uniformity of products and the like, thereby seriously influencing the application of the magnetic metal fullerene in the field of tumor treatment.

Disclosure of Invention

In view of the above, the present invention aims to provide a drug sustained-release anti-tumor nano robot and a preparation method thereof, the preparation method provided by the present invention has a stable production process, and the drug sustained-release anti-tumor nano robot prepared by the method has good size uniformity, paramagnetism, anti-tumor function and drug sustained-release effect, and has a wide application prospect in the field of tumor treatment.

The invention provides a preparation method of a drug sustained-release anti-tumor nano robot, which comprises the following steps:

a) placing a paramagnetic metal target material in a sputtering chamber, introducing argon and oxygen into the sputtering chamber, and starting a power supply of the sputtering chamber to perform magnetron sputtering; in the magnetron sputtering process, the temperature of a cavity of the sputtering chamber is 800-1200 ℃;

b) after the magnetron sputtering is finished, maintaining the temperature of a cavity of the sputtering chamber at 800-1200 ℃, and introducing acetylene gas into the sputtering chamber;

c) after the acetylene gas is introduced, introducing protective gas into the sputtering chamber, and reducing the temperature of the cavity of the sputtering chamber to 100-300 ℃ within 5-15 min to obtain the internally-wrapped paramagnetic metal fullerene particles;

d) mixing the paramagnetic metal fullerene particles, the antitumor drug, the polylactic acid and the volatile organic solvent to obtain a mixed solution;

e) mixing the mixed solution with water, stirring and volatilizing the volatile organic solvent in the mixed system to obtain a suspension;

f) and carrying out centrifugal separation on the suspension, and discarding the supernatant to obtain the drug sustained-release anti-tumor nano robot.

Preferably, in step a), the paramagnetic metal target includes one or more of iron oxide, titanium oxide, and zirconium oxide.

Preferably, in the step a), the vacuum degree of the sputtering chamber is 10-30 Pa in the magnetron sputtering process; the gas inflow rate of the argon is 40-50 sccm; the air inflow rate of the oxygen is 10-15 sccm.

Preferably, in the step b), the vacuum degree of the sputtering chamber is 10-30 Pa; the gas inflow rate of the acetylene gas is 100-120 sccm.

Preferably, in the step c), the particle size of the encapsulated paramagnetic metal fullerene particles is 1-100 nm.

Preferably, in step d), the anti-tumor drug comprises one or more of paclitaxel, dexamethasone and ranophanin.

Preferably, in the step d), the mass ratio of the encapsulated paramagnetic metal fullerene particles to the antitumor drug to the polylactic acid is (2-5): (2-5): 1.

preferably, in step d), folic acid and/or a surfactant are also contained in the suspension.

Preferably, the surfactant comprises one or more of tween80, tween 20 and a poloxamer.

The invention provides a drug sustained-release anti-tumor nano robot prepared by the preparation method according to the technical scheme.

Compared with the prior art, the invention provides a drug sustained-release anti-tumor nano robot and a preparation method thereof. The preparation method provided by the invention comprises the following steps: a) placing a paramagnetic metal target material in a sputtering chamber, introducing argon and oxygen into the sputtering chamber, and starting a power supply of the sputtering chamber to perform magnetron sputtering; in the magnetron sputtering process, the temperature of a cavity of the sputtering chamber is 800-1200 ℃; b) after the magnetron sputtering is finished, maintaining the temperature of a cavity of the sputtering chamber at 800-1200 ℃, and introducing acetylene gas into the sputtering chamber; c) after the acetylene gas is introduced, introducing protective gas into the sputtering chamber, and reducing the temperature of the cavity of the sputtering chamber to 100-300 ℃ within 5-15 min to obtain the internally-wrapped paramagnetic metal fullerene particles; d) mixing the paramagnetic metal fullerene particles, the antitumor drug, the polylactic acid and the volatile organic solvent to obtain a mixed solution; e) mixing the mixed solution with water, stirring and volatilizing the volatile organic solvent in the mixed system to obtain a suspension; f) and carrying out centrifugal separation on the suspension, and discarding the supernatant to obtain the drug sustained-release anti-tumor nano robot. Firstly, preparing small-size paramagnetic metal-encapsulated fullerene particles with good paramagnetism and particle size uniformity by using magnetron sputtering equipment under specific process conditions; then uniformly mixing the paramagnetic metal fullerene particles, the antitumor drug and the polylactic acid in the volatile organic solvent; then mixing the suspension with water and stirring to volatilize the volatile organic solvent to obtain a suspension; finally, insoluble substances in the suspension are separated out in a centrifugal separation mode, and the drug sustained-release anti-tumor nano robot prepared by the invention is obtained. According to the preparation method provided by the invention, the wrapped paramagnetic metal fullerene with good paramagnetism is added into the nano robot, so that the nano robot can show good paramagnetism; the anti-tumor drug is loaded in the nano robot, so that the nano robot can show more excellent tumor treatment effect; the polylactic acid is added into the nano robot, so that the degradation speed of the nano robot can be regulated and controlled, the drug release speed of the nano robot is controlled to a certain extent, and the purposes of drug slow release and long-acting release are achieved. The drug sustained-release anti-tumor nano robot prepared by the method has good size uniformity, paramagnetism, anti-tumor function and drug sustained-release effect, and can efficiently block tumor blood vessels in a targeted manner under the assistance of radio frequency to kill tumor cells; meanwhile, after the tumor cells are killed, the medicine can be completely degraded or absorbed by a human body within 3-5 weeks, and has no side effect. The preparation method provided by the invention has stable and controllable production process, is suitable for industrialization, and has wide application prospect in the field of tumor treatment.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention provides a preparation method of a drug sustained-release anti-tumor nano robot, which comprises the following steps:

a) placing a paramagnetic metal target material in a sputtering chamber, introducing argon and oxygen into the sputtering chamber, and starting a power supply of the sputtering chamber to perform magnetron sputtering; in the magnetron sputtering process, the temperature of a cavity of the sputtering chamber is 800-1200 ℃;

b) after the magnetron sputtering is finished, maintaining the temperature of a cavity of the sputtering chamber at 800-1200 ℃, and introducing acetylene gas into the sputtering chamber;

c) after the acetylene gas is introduced, introducing protective gas into the sputtering chamber, and reducing the temperature of the cavity of the sputtering chamber to 100-300 ℃ within 5-15 min to obtain the internally-wrapped paramagnetic metal fullerene particles;

d) mixing the paramagnetic metal fullerene particles, the antitumor drug, the polylactic acid and the volatile organic solvent to obtain a mixed solution;

e) mixing the mixed solution with water, stirring and volatilizing the volatile organic solvent in the mixed system to obtain a suspension;

f) and carrying out centrifugal separation on the suspension, and discarding the supernatant to obtain the drug sustained-release anti-tumor nano robot.

In the preparation method provided by the invention, a paramagnetic metal target is firstly placed in a sputtering chamber. Wherein, the paramagnetic metal target material preferably comprises one or more of iron oxide, titanium oxide and zirconium oxide. Then, argon and oxygen are introduced into the sputtering chamber, and a power supply of the sputtering chamber is started to carry out magnetron sputtering. Wherein the flow rate of the argon gas is preferably 40-50 sccm, and specifically can be 40sccm, 41sccm, 42sccm, 43sccm, 44sccm, 45sccm, 46sccm, 47sccm, 48sccm, 49sccm or 50 sccm; the aeration time of the argon is consistent with the time of magnetron sputtering; the flow rate of the inlet gas of the oxygen is preferably 10-15 sccm, and specifically 10sccm, 11sccm, 12sccm, 13sccm, 14sccm or 15 sccm; the aeration time of the oxygen is preferably 3-5 min, and specifically can be 3min, 3.5min, 4min, 4.5min or 5 min; the power supply is preferably a Direct Current (DC) power supply; the voltage of the power supply is preferably 330-420V, and specifically can be 330V, 340V, 350V, 360V, 370V, 380V, 390V, 400V, 410V or 420V; the power of the power supply is preferably 2400-3600W, and specifically can be 2400W, 2500W, 2600W, 2700W, 2800W, 2900W, 3000W, 3100W, 3200W, 3300W, 3400W, 3500W or 3600W; in the magnetron sputtering process, the vacuum degree of the sputtering chamber is preferably controlled to be 10-30 Pa, and specifically 10Pa, 15Pa, 20Pa, 25Pa or 30 Pa; in the magnetron sputtering process, the temperature of the cavity of the sputtering chamber is preferably controlled at 800-1200 ℃, and specifically can be 800 ℃, 850 ℃, 900 ℃, 950 ℃, 1000 ℃, 1050 ℃, 1100 ℃, 1150 ℃ or 1200 ℃; the magnetron sputtering time is preferably 5-8 min, and specifically can be 5min, 5.5min, 6min, 6.5min, 7min, 7.5min or 8 min.

In the preparation method provided by the invention, acetylene gas is introduced into the sputtering chamber after the magnetron sputtering is finished. In the process of introducing the acetylene gas, the temperature of the cavity of the sputtering chamber is maintained at 800-1200 ℃, and specifically can be 800 ℃, 850 ℃, 900 ℃, 950 ℃, 1000 ℃, 1050 ℃, 1100 ℃, 1150 ℃ or 1200 ℃; the vacuum degree of the sputtering chamber is preferably controlled to be 10-30 Pa, and specifically can be 10Pa, 15Pa, 20Pa, 25Pa or 30 Pa; the inflow rate of the acetylene gas is preferably 100-120 sccm, and specifically can be 100sccm, 105sccm, 110sccm, 115sccm or 120 sccm; the preferable aeration time of the acetylene gas is 10-15 min, and specifically can be 10min, 10.5min, 11min, 11.5min, 12min, 12.5min, 13min, 13.5min, 14min, 14.5min or 15 min.

In the preparation method provided by the invention, after the acetylene gas is introduced, protective gas is introduced into the sputtering chamber, and the sputtering chamber is rapidly cooled. The vacuum degree of the sputtering chamber is preferably controlled to be 10-30 Pa, and specifically can be 10Pa, 15Pa, 20Pa, 25Pa or 30 Pa; the protective gas is preferably argon and/or nitrogen; the flow rate of the shielding gas is preferably 700 to 1000sccm, and specifically 700sccm, 750sccm, 800sccm, 850sccm, 900sccm, 950sccm or 1000 sccm. In the invention, the process of rapidly cooling is preferably to reduce the temperature of the cavity of the sputtering chamber to 100-300 ℃ within 5-15 min, and the time consumed by rapidly cooling is more preferably 8-10 min, specifically 8min, 8.5min, 9min, 9.5min or 10 min; the temperature of the cavity after the rapid cooling is more preferably 150-250 ℃, and specifically can be 150 ℃, 160 ℃, 170 ℃, 180 ℃, 190 ℃, 200 ℃, 210 ℃, 220 ℃, 230 ℃, 240 ℃ or 250 ℃. After the rapid cooling is finished, obtaining inner-wrapped paramagnetic metal fullerene particles, wherein the inner-wrapped paramagnetic metal fullerene particles comprise paramagnetic metal particles and carbon spheres which wrap the paramagnetic metal particles and have fullerene shapes; the paramagnetic metal particles preferably comprise one or more of Fe, Zr, and Ti; the particle size of the fullerene particles containing the paramagnetic metal is preferably 1-100 nm, more preferably 10-30 nm, and specifically 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 55nm, 60nm, 65nm, 70nm, 75nm, 80nm, 85nm, 90nm, 95nm or 100 nm.

In an embodiment provided by the present invention, the internally-encapsulated paramagnetic metal fullerene particles are prepared in a magnetron sputtering apparatus provided with a wafer inlet chamber, a sputtering chamber and a wafer outlet chamber, and the prepared internally-encapsulated paramagnetic metal fullerene particles are loaded by using a work holder, specifically including the following steps:

cleaning a workpiece clamp, then installing the workpiece clamp on a moving track of a magnetron sputtering device, enabling the workpiece clamp to enter a wafer inlet chamber along the track, closing a vacuum valve of the wafer inlet chamber, vacuumizing the wafer inlet chamber, opening the vacuum valve of the sputtering chamber after the vacuum degree meets the requirement, and enabling the workpiece clamp to enter the sputtering chamber along the track; the preparation of the fullerene particles containing the paramagnetic metal is carried out in the sputtering chamber, and the specific process is described above and is not described again; the encapsulated paramagnetic metal fullerene particles generated by rapid cooling are adsorbed around the workpiece clamp; the working clamp moves to the sheet outlet chamber along the operation track and is naturally cooled to room temperature under the protective gas atmosphere; and opening a vacuum valve of the sheet outlet chamber, enabling the working clamp to leave the sheet outlet chamber along the rail, and then collecting the paramagnetic metal fullerene particles internally wrapped on the working clamp.

In the invention, taking paramagnetic metal as Fe as an example, the physical and chemical processes involved in the preparation process of the fullerene particle containing the paramagnetic metal are as follows: after a power supply of the sputtering chamber is started, positive argon ions generated by ionization bombard the iron target to sputter Fe particles from the target, and the sputtered Fe particles are in an oxygen atmosphere, so that 2P of iron can be obtained due to the fact that the oxygen atoms are atoms with larger electronegativity¹And 2P³The characteristic peak moves to the direction with higher binding energy, so that Fe particles exist in the form of iron oxide; then leading acetylene gas into the sputtering chamber to surround and coat Fe particles, and reacting at high temperature to generate a carbon tube prototype; and finally, splitting the carbon tube prototype by rapid cooling to form carbon spheres coated with Fe particles, and generating fullerene morphology, namely the fullerene particles (Fe @ fullerene) coated with paramagnetic metal prepared by the invention.

In the preparation method provided by the invention, after the paramagnetic metal fullerene particles are encapsulated, the paramagnetic metal fullerene particles, the antitumor drug, the polylactic acid and the volatile organic solvent are mixed to obtain a mixed solution. Wherein the anti-tumor drug includes, but is not limited to, one or more of Paclitaxel (PTX), Dexamethasone (DXM) and ranafol; the number average molecular weight of the polylactic acid is preferably 10000-50000, and specifically can be 10000, 15000, 20000, 25000, 30000, 35000, 40000, 45000 or 50000; the volatile organic solvents include, but are not limited to, acetone; the mass ratio of the fullerene particles internally coated with paramagnetic metal to the polylactic acid is preferably (2-5): 1, specifically 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1 or 5: 1; the mass ratio of the antitumor drug to the polylactic acid is preferably (2-5): 1, specifically 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1 or 5: 1; the mass ratio of the volatile organic solvent to the polylactic acid is preferably (2-5): 1, specifically 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1 or 5: 1. In the invention, the polylactic acid (PLA) is non-toxic and biodegradable, and has good biocompatibility, and the degradation speed of the polylactic acid is related to the molecular weight, so that the degradation speed of the nano-robot can be regulated and controlled by selecting the polylactic acid with the proper molecular weight, the release speed of the anti-tumor drug can be controlled to a certain extent, and the purposes of drug slow release and long-acting release can be achieved.

In one embodiment of the present invention, the mixed solution is preferably prepared according to the following steps:

i) mixing the antitumor drug and the volatile organic solvent to obtain a liquid medicine;

ii) sequentially adding polylactic acid and the encapsulated paramagnetic metal fullerene particles into the liquid medicine, and mixing to obtain a mixed solution.

In the step of preparing the mixed solution provided in the above embodiment of the present invention, in step i), the mixing is preferably performed under a stirring condition, and the rotation speed of the stirring is preferably 200 to 300r/min, and specifically may be 200r/min, 250r/min, or 300 r/min; the mixing time is preferably 10-15 min, and specifically can be 10min, 11min, 12min, 13min, 14min or 15 min.

In the step of preparing the mixed solution provided by the above embodiment of the present invention, in the step ii), the mixing is preferably performed under stirring and ultrasonic conditions, and the rotation speed of the stirring is preferably 200 to 300r/min, and specifically may be 200r/min, 250r/min or 300 r/min; the mixing time is preferably 30-60 min, and specifically can be 30min, 35min, 40min, 45min, 50min, 55min or 60 min.

In the preparation method provided by the invention, after the mixed solution is obtained, the mixed solution is mixed with water and stirred to volatilize the volatile organic solvent in the mixed system, so as to obtain the suspension. Wherein the mass ratio of the mixed liquid to water is preferably 4: (4-8), specifically 4:4, 4:5, 4:6, 4:7 or 4: 8; the rotation speed of the stirring is preferably 500-2000 r/min, and specifically can be 500r/min, 800r/min, 1000r/min, 1200r/min, 1500r/min, 1700r/min or 2000 r/min; the stirring time is preferably 30-60 min, and specifically can be 30min, 35min, 40min, 45min, 50min, 55min or 60 min.

In the preparation method provided by the invention, the suspension preferably further contains folic acid and/or a surfactant. The folic acid can specifically react with a folic acid receptor on the surface of a cell to form a compound, the binding force of the folic acid and the folic acid is very strong, the folic acid has high selectivity on tumors, and the folic acid can be used as a modified compound of a tumor-targeted drug; the surfactant mainly has a modification and encapsulation effect on the surface of the nano-robot, and includes but is not limited to one or more of TWEEN80 (TWEEN 80), TWEEN 20(TWEEN 20) and poloxamer, and TWEEN80 is preferred. In one embodiment provided by the present invention, the folic acid and the surfactant are preferably added to the suspension in the following manner:

firstly, mixing a nonionic surfactant aqueous solution and a folic acid aqueous solution to obtain a mixture aqueous solution; then, an aqueous solution of the mixture was added dropwise to the suspension.

In the addition manner of the nonionic surfactant and the folic acid provided in the above embodiment of the present invention, the concentration of the nonionic surfactant aqueous solution is preferably 0.5 to 6 wt%, and specifically may be 0.5 wt%, 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt%, 5 wt%, 5.5 wt%, or 6 wt%; the concentration of the folic acid aqueous solution is preferably 10 to 50 wt%, and specifically may be 10 wt%, 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt%, 45 wt%, or 50 wt%; the mass ratio of the nonionic surfactant aqueous solution to the folic acid aqueous solution is preferably 6: (2-6), specifically 6:2, 6:2.5, 6:3, 6:3.5, 6:4, 6:4.5, 6:5, 6:5.5 or 6: 6; the mixing of the nonionic surfactant aqueous solution and the folic acid aqueous solution is preferably carried out under the condition of stirring, the stirring speed is preferably 500-2000 r/min, specifically 500r/min, 1000r/min, 1500r/min or 2000r/min, and the mixing time is preferably 10-30 min, specifically 10min, 15min, 20min, 25min or 30 min.

In the addition manner of the nonionic surfactant and the folic acid provided in the above embodiment of the present invention, the volume ratio of the mixture aqueous solution to the suspension is preferably 3: (5-10), specifically 3:5, 3:5.5, 3:6, 3:6.5, 3:7, 3:7.5, 3:8, 3:8.5, 3:9, 3:9.5 or 3: 10; the dropping speed is preferably 5-20 mL/min, and specifically can be 5mL/min, 10mL/min, 15mL/min or 20 mL/min.

In the preparation method provided by the invention, after the suspension is obtained, the suspension is subjected to centrifugal separation. Wherein the rotating speed of the centrifugal separation is preferably 8000-10000 r/min, and specifically 8000r/min, 8500r/min, 9000r/min, 9500r/min or 10000 r/min; the time of the centrifugal separation is preferably 100-120 min, and specifically can be 100min, 105min, 110min, 115min or 120 min. And after the centrifugal separation is finished, removing the supernatant to obtain the drug sustained-release anti-tumor nano robot. In the invention, the nano robot obtained by centrifugal separation is preferably dried, and the drying temperature is preferably 60-100 ℃, and specifically can be 60 ℃, 65 ℃, 70 ℃, 75 ℃, 80 ℃, 85 ℃, 90 ℃, 95 ℃ or 100 ℃; the drying time is preferably 60-90 min, and specifically can be 60min, 65min, 70min, 75min, 80min, 85min, 90min, 95min or 100 min.

Firstly, preparing small-size paramagnetic metal-encapsulated fullerene particles with good paramagnetism and particle size uniformity by using magnetron sputtering equipment under specific process conditions; then uniformly mixing the coated paramagnetic metal fullerene particles, the antitumor drug and the polylactic acid in a volatile organic solvent; then mixing the suspension with water and stirring to volatilize the volatile organic solvent to obtain a suspension; finally, insoluble substances in the suspension are separated out in a centrifugal separation mode, and the drug sustained-release anti-tumor nano robot prepared by the invention is obtained. According to the preparation method provided by the invention, the wrapped paramagnetic metal fullerene with good paramagnetism is added into the nano robot, so that the nano robot can show good paramagnetism; the anti-tumor drug is loaded in the nano robot, so that the nano robot can show more excellent tumor treatment effect; the polylactic acid is added into the nano robot, so that the degradation speed of the nano robot can be regulated and controlled, the drug release speed of the nano robot is controlled to a certain extent, and the purposes of drug slow release and long-acting release are achieved. The drug sustained-release anti-tumor nano robot prepared by the method has good size uniformity, paramagnetism and anti-tumor functions, and controllable size, and can efficiently block tumor blood vessels in a targeted manner under the assistance of radio frequency to kill tumor cells; meanwhile, after the tumor cells are killed, the medicine can be completely degraded or absorbed by a human body within 3-5 weeks, and has no side effect. The preparation method provided by the invention has stable and controllable production process, is suitable for industrialization, and has wide application prospect in the field of tumor treatment.

The invention also provides a drug sustained-release anti-tumor nano robot prepared by the method of the technical scheme. The drug sustained-release anti-tumor nano robot provided by the invention has good size uniformity, paramagnetism, anti-tumor function and drug sustained-release effect, and can efficiently block tumor blood vessels in a targeted manner under the assistance of radio frequency to kill tumor cells; meanwhile, after tumor cells are killed, the drug can be completely degraded or absorbed by a human body within 3-5 weeks without any side effect, so that the drug sustained-release anti-tumor nano robot provided by the invention has a wide application prospect in the field of tumor treatment. In addition, the metal fullerene has excellent free radical scavenging effect and has the function of resisting oxidation damage and repairing various cells, so the drug sustained-release anti-tumor nano robot provided by the invention can also be used as a drug and has good treatment effect on various diseases.

For the sake of clarity, the following examples are given in detail.

Example 1

Preparation of Fe @ fullerene particles, comprising the steps of:

1) cleaning: firstly, wiping a glass workpiece clamp with alcohol, then putting the workpiece clamp into an ultrasonic cleaning machine, carrying out deionized water ultra-cleaning and alcohol ultra-cleaning, and finally putting the workpiece clamp into alcohol steam for drying;

2) pasting a protective film: sticking a polyethylene film on the cleaned workpiece clamp, protecting the cleanliness of the workpiece clamp and protecting the workpiece clamp from being damaged;

3) installing the workpiece clamp pasted with the film on a running track of a magnetron sputtering device, and tearing off the protective film before entering a film inlet chamber;

4) the working clamp moves to a film feeding chamber of the magnetron sputtering device, then a vacuum gate valve is closed, and a vacuum pump is started to keep the vacuum degree at 15 Pa;

5) opening a vacuum gate valve of a sputtering chamber of the magnetron sputtering device, and enabling the workpiece clamp to enter the fixed position of the sputtering chamber through a track;

6) introducing argon and oxygen into the sputtering chamber, starting a DC power supply (380V and 3000W) of the sputtering chamber, bombarding an iron target (ferric oxide) for magnetron sputtering, and keeping for 5 min; wherein the argon flow is 45sccm, and the ventilation time is consistent with the time for performing magnetron sputtering; the oxygen flow is 10sccm, and the ventilation time is 3 min; during magnetron sputtering, the temperature of the cavity of the sputtering chamber is maintained at 1000 ℃;

7) after the magnetron sputtering is finished, maintaining the temperature of a cavity of the sputtering chamber to be 1000 ℃, and introducing acetylene gas into the sputtering chamber, wherein the flow rate of the acetylene gas is 100sccm, and the introduction time is 10 min;

8) after the acetylene gas is introduced, introducing argon gas as a protective gas, introducing the amount of 800sccm, and simultaneously starting a cooling device to ensure that the temperature of the cavity of the sputtering chamber is up to 200 ℃ within 10min to obtain carbon sphere particles adsorbed around the working clamp, namely the internally-wrapped paramagnetic metal fullerene particles prepared by the embodiment;

9) then, the working clamp moves to a film discharging chamber of the magnetron sputtering device along the operation track, protective gas argon is introduced into the film discharging chamber, the introduction amount is 300sccm, and the film discharging chamber is naturally cooled to 25 ℃;

10) and opening a vacuum valve of the sheet outlet chamber, enabling the working clamp to leave the sheet outlet chamber along the rail, and then collecting the internally-wrapped paramagnetic metal fullerene particles on the working clamp to obtain the internally-wrapped paramagnetic metal fullerene particles.

The particle size, particle size uniformity, purity, graphitization degree, saturation magnetization, residual magnetization, and coercive force of the encapsulated paramagnetic metal fullerene particles prepared in this example were measured.

The particle size and the particle size uniformity are obtained by analyzing the morphology and the crystallization morphology of the prepared inner-wrapped paramagnetic metal fullerene particles by using a JEM-2010 high-resolution transmission electron microscope, and the calculation formula of the particle size uniformity is as follows: (D)_{Big (a)}-D_Small)/(D_{Big (a)}+D_Small)×100％，D_{Big (a)}Denotes the maximum diameter value, D, measured from the granules prepared_SmallRepresents the smallest diameter measured from the prepared particles;

the purity and graphitization degree are obtained by performing water solubility analysis on the prepared inner-wrapped paramagnetic metal fullerene particles by using an FES165 Fourier infrared spectrometer (FT-IR) and a cary-300VARIAN ultraviolet visible spectrum analyzer;

the magnetization and coercive force were obtained by performing magnetic property analysis of the prepared internally-wrapped paramagnetic metal fullerene particles using a Lakeshore 7410 vibrating sample magnetometer.

The measurement results are as follows: the grain size is 80-90 nm, the uniformity of the grain size is less than 5.8%, the purity is more than 99.9%, the graphitization degree is more than 94%, the saturation magnetization is 19.655emu/G, the residual magnetization is 4.4944emu/G, and the coercive force is 567.86G.

Example 2

The preparation of the drug sustained-release anti-tumor nano robot comprises the following steps:

1) dissolving paclitaxel in acetone, stirring for 10-15 min until the paclitaxel is completely dissolved, then sequentially adding polylactic acid (with the number average molecular weight of 20000) and the Fe @ fullerene particles prepared in example 1 (the mass ratio of the paclitaxel to the acetone to the polylactic acid to the Fe @ fullerene particles is 3:3:1:3), stirring while performing ultrasound, wherein the stirring speed is 200r/min, and the stirring time is 45min, so as to obtain a mixed solution.

2) Slowly adding deionized water into the mixed solution prepared in the step 1) under the stirring condition, wherein the mass ratio of the mixed solution to the deionized water is 4:6, continuously stirring for a certain time, and volatilizing to remove acetone to obtain colloidal suspension with opalescence. Wherein the stirring speed is 1000r/min, and the stirring time is about 40 minutes.

3) Mixing an aqueous solution of TWEEN80 with a concentration of 4 wt% and an aqueous solution of folic acid with a concentration of 30 wt% according to a mass ratio of 6:4, and stirring at a stirring speed of 1000r/min for 20min to obtain a mixture aqueous solution.

4) Slowly dripping the mixture water solution prepared in the step 3) into the suspension prepared in the step 2), wherein the volume ratio of the mixture water solution to the suspension is 3:7, the dripping speed is 10mL/min, and stirring and mixing for 30min after dripping.

5) Placing the mixture prepared in the step 4) in a centrifuge tube, and centrifuging for 100min at 9000 r/min. And then, removing the supernatant, and placing the centrifugal tube in a vacuum drying oven to constant weight (the drying temperature is 80 ℃, and the drying time is about 70min) to obtain the drug sustained-release anti-tumor nano robot.

The prepared drug sustained-release anti-tumor nano robot is observed by a transmission electron microscope (JEM-100SX transmission electron microscope, JEOL company, Japan), and the result shows that: most of the drug sustained-release antitumor nano-robots prepared by the embodiment are round and uniform spherical particles, the average particle size is 170nm, and no adhesion exists among the particles.

Example 3

A) Preparation of Fe @ fullerene particles, comprising the steps of:

1) cleaning: firstly, wiping a glass workpiece clamp with alcohol, then putting the workpiece clamp into an ultrasonic cleaning machine, carrying out deionized water ultra-cleaning and alcohol ultra-cleaning, and finally putting the workpiece clamp into alcohol steam for drying;

2) pasting a protective film: sticking a polyethylene film on the cleaned workpiece clamp, protecting the cleanliness of the workpiece clamp and protecting the workpiece clamp from being damaged;

3) installing the workpiece clamp pasted with the film on a running track of a magnetron sputtering device, and tearing off the protective film before entering a film inlet chamber;

4) the working clamp moves to a film feeding chamber of the magnetron sputtering device, then a vacuum gate valve is closed, and a vacuum pump is started to keep the vacuum degree at 15 Pa;

5) opening a vacuum gate valve of a sputtering chamber of the magnetron sputtering device, and enabling the workpiece clamp to enter the fixed position of the sputtering chamber through a track;

6) introducing argon and oxygen into the sputtering chamber, starting a DC power supply (400V and 3200W) of the sputtering chamber, bombarding an iron target (ferric oxide) for magnetron sputtering, and keeping for 6 min; wherein the argon flow is 48sccm, and the ventilation time is consistent with the time for performing magnetron sputtering; the oxygen flow is 12sccm, and the ventilation time is 4 min; during magnetron sputtering, the temperature of the cavity of the sputtering chamber is maintained at 950 ℃;

7) after the magnetron sputtering is finished, maintaining the temperature of a cavity of the sputtering chamber at 950 ℃, and introducing acetylene gas into the sputtering chamber, wherein the flow rate of the acetylene gas is 110sccm, and the introduction time is 10 min;

8) after the acetylene gas is introduced, introducing argon gas as a protective gas, introducing the amount of 800sccm, and simultaneously starting a cooling device to ensure that the temperature of the cavity of the sputtering chamber is up to 200 ℃ within 10min to obtain carbon sphere particles adsorbed around the working clamp, namely the internally-wrapped paramagnetic metal fullerene particles prepared by the embodiment;

9) then, the working clamp moves to a film discharging chamber of the magnetron sputtering device along the operation track, protective gas argon is introduced into the film discharging chamber, the introduction amount is 300sccm, and the film discharging chamber is naturally cooled to 25 ℃;

10) and opening a vacuum valve of the sheet outlet chamber, enabling the working clamp to leave the sheet outlet chamber along the rail, and then collecting the internally-wrapped paramagnetic metal fullerene particles on the working clamp to obtain the internally-wrapped paramagnetic metal fullerene particles.

The particle size, particle size uniformity, purity, graphitization degree, saturation magnetization, residual magnetization, and coercive force of the encapsulated paramagnetic metal fullerene particles prepared in this example were measured.

The particle size and the particle size uniformity are obtained by analyzing the morphology and the crystallization morphology of the prepared inner-wrapped paramagnetic metal fullerene particles by using a JEM-2010 high-resolution transmission electron microscope, and the calculation formula of the particle size uniformity is as follows: (D)_{Big (a)}-D_Small)/(D_{Big (a)}+D_Small)×100％，D_{Big (a)}Denotes the maximum diameter value, D, measured from the granules prepared_SmallRepresents the smallest diameter measured from the prepared particles;

the purity and graphitization degree are obtained by performing water solubility analysis on the prepared inner-wrapped paramagnetic metal fullerene particles by using an FES165 Fourier infrared spectrometer (FT-IR) and a cary-300VARIAN ultraviolet visible spectrum analyzer;

the magnetization and coercive force were obtained by performing magnetic property analysis of the prepared internally-wrapped paramagnetic metal fullerene particles using a Lakeshore 7410 vibrating sample magnetometer.

The measurement results are as follows: the grain size is 90-100 nm, the uniformity of the grain size is less than 5.9%, the purity is more than 99.9%, the graphitization degree is more than 95%, the saturation magnetization is 19.629emu/G, the residual magnetization is 4.4872emu/G, and the coercive force is 566.56G.

B) The preparation of the drug sustained-release anti-tumor nano robot comprises the following steps:

1) dissolving paclitaxel in acetone, stirring for 10-15 min until the paclitaxel is completely dissolved, then sequentially adding polylactic acid (with the number average molecular weight of 20000) and the Fe @ fullerene particles prepared in the step A) (the mass ratio of the paclitaxel, the acetone, the polylactic acid and the Fe @ fullerene particles is 3:3:1:3), stirring while performing ultrasound, stirring at the speed of 200r/min, and stirring for 40min to obtain a mixed solution.

2) Slowly adding deionized water into the mixed solution prepared in the step 1) under the stirring condition, wherein the mass ratio of the mixed solution to the deionized water is 4:6, continuously stirring for a certain time, and volatilizing to remove acetone to obtain colloidal suspension with opalescence. Wherein the stirring speed is 1000r/min, and the stirring time is about 40 minutes.

3) Mixing an aqueous solution of TWEEN80 with a concentration of 4 wt% and an aqueous solution of folic acid with a concentration of 30 wt% according to a mass ratio of 6:4, and stirring at a stirring speed of 1000r/min for 20min to obtain a mixture aqueous solution.

4) Slowly dripping the mixture water solution prepared in the step 3) into the suspension prepared in the step 2), wherein the volume ratio of the mixture water solution to the suspension is 3:7, the dripping speed is 10mL/min, and stirring and mixing for 30min after dripping.

5) Placing the mixture prepared in the step 4) in a centrifuge tube, and centrifuging for 100min at 9000 r/min. And then, removing the supernatant, and placing the centrifugal tube in a vacuum drying oven to constant weight (the drying temperature is 80 ℃, and the drying time is about 70min) to obtain the drug sustained-release anti-tumor nano robot.

The prepared drug sustained-release anti-tumor nano robot is observed by a transmission electron microscope (JEM-100SX transmission electron microscope, JEOL company, Japan), and the result shows that: most of the drug sustained-release antitumor nano-robots prepared by the embodiment are round and uniform spherical particles, the average particle size is 190nm, and no adhesion exists among the particles.

Example 4

A) Preparation of Fe @ fullerene particles, comprising the steps of:

1) cleaning: firstly, wiping a glass workpiece clamp with alcohol, then putting the workpiece clamp into an ultrasonic cleaning machine, carrying out deionized water ultra-cleaning and alcohol ultra-cleaning, and finally putting the workpiece clamp into alcohol steam for drying;

2) pasting a protective film: sticking a polyethylene film on the cleaned workpiece clamp, protecting the cleanliness of the workpiece clamp and protecting the workpiece clamp from being damaged;

3) installing the workpiece clamp pasted with the film on a running track of a magnetron sputtering device, and tearing off the protective film before entering a film inlet chamber;

4) the working clamp moves to a film feeding chamber of the magnetron sputtering device, then a vacuum gate valve is closed, and a vacuum pump is started to keep the vacuum degree at 15 Pa;

5) opening a vacuum gate valve of a sputtering chamber of the magnetron sputtering device, and enabling the workpiece clamp to enter the fixed position of the sputtering chamber through a track;

6) introducing argon and oxygen into the sputtering chamber, starting a DC power supply (420V, 3600W) of the sputtering chamber, bombarding an iron target (ferric oxide) for magnetron sputtering, and keeping for 8 min; wherein the argon flow is 50sccm, and the ventilation time is consistent with the time for performing magnetron sputtering; the oxygen flow is 15sccm, and the ventilation time is 5 min; during magnetron sputtering, the temperature of the cavity of the sputtering chamber is maintained at 1000 ℃;

7) after the magnetron sputtering is finished, maintaining the temperature of a cavity of the sputtering chamber to be 1000 ℃, and introducing acetylene gas into the sputtering chamber, wherein the flow rate of the acetylene gas is 120sccm, and the introduction time is 10 min;

8) after the acetylene gas is introduced, introducing argon gas as a protective gas, introducing the amount of 800sccm, and simultaneously starting a cooling device to ensure that the temperature of the cavity of the sputtering chamber is up to 200 ℃ within 10min to obtain carbon sphere particles adsorbed around the working clamp, namely the internally-wrapped paramagnetic metal fullerene particles prepared by the embodiment;

9) then, the working clamp moves to a film discharging chamber of the magnetron sputtering device along the operation track, protective gas argon is introduced into the film discharging chamber, the introduction amount is 300sccm, and the film discharging chamber is naturally cooled to 25 ℃;

10) and opening a vacuum valve of the sheet outlet chamber, enabling the working clamp to leave the sheet outlet chamber along the rail, and then collecting the internally-wrapped paramagnetic metal fullerene particles on the working clamp to obtain the internally-wrapped paramagnetic metal fullerene particles.

The particle size, particle size uniformity, purity, graphitization degree, saturation magnetization, residual magnetization, and coercive force of the encapsulated paramagnetic metal fullerene particles prepared in this example were measured.

The particle size and the particle size uniformity are obtained by analyzing the morphology and the crystallization morphology of the prepared inner-wrapped paramagnetic metal fullerene particles by using a JEM-2010 high-resolution transmission electron microscope, and the calculation formula of the particle size uniformity is as follows: (D)_{Big (a)}-D_Small)/(D_{Big (a)}+D_Small)×100％，D_{Big (a)}Denotes the maximum diameter value, D, measured from the granules prepared_SmallRepresents the smallest diameter measured from the prepared particles;

the purity and graphitization degree are obtained by performing water solubility analysis on the prepared inner-wrapped paramagnetic metal fullerene particles by using an FES165 Fourier infrared spectrometer (FT-IR) and a cary-300VARIAN ultraviolet visible spectrum analyzer;

the magnetization and coercive force were obtained by performing magnetic property analysis of the prepared internally-wrapped paramagnetic metal fullerene particles using a Lakeshore 7410 vibrating sample magnetometer.

The measurement results are as follows: the grain size is 100-120 nm, the uniformity of the grain size is less than 5.1%, the purity is more than 99.9%, the graphitization degree is more than 94%, the saturation magnetization is 19.779emu/G, the residual magnetization is 4.4392emu/G, and the coercive force is 586.36G.

B) The preparation of the drug sustained-release anti-tumor nano robot comprises the following steps:

1) dissolving paclitaxel in acetone, stirring for 10-15 min until the paclitaxel is completely dissolved, then sequentially adding polylactic acid (with the number average molecular weight of 20000) and the Fe @ fullerene particles prepared in the step A) (the mass ratio of the paclitaxel, the acetone, the polylactic acid and the Fe @ fullerene particles is 3:3:1:3), stirring while performing ultrasound, stirring at the speed of 200r/min, and stirring for 50min to obtain a mixed solution.

2) Slowly adding deionized water into the mixed solution prepared in the step 1) under the stirring condition, wherein the mass ratio of the mixed solution to the deionized water is 4:6, continuously stirring for a certain time, and volatilizing to remove acetone to obtain colloidal suspension with opalescence. Wherein the stirring speed is 1000r/min, and the stirring time is about 40 minutes.

3) Mixing an aqueous solution of TWEEN80 with a concentration of 4 wt% and an aqueous solution of folic acid with a concentration of 30 wt% according to a mass ratio of 6:4, and stirring at a stirring speed of 1000r/min for 20min to obtain a mixture aqueous solution.

4) Slowly dripping the mixture water solution prepared in the step 3) into the suspension prepared in the step 2), wherein the volume ratio of the mixture water solution to the suspension is 3:7, the dripping speed is 15mL/min, and stirring and mixing for 30min after dripping.

5) Placing the mixture prepared in the step 4) in a centrifuge tube, and centrifuging for 100min at 9000 r/min. And then, removing the supernatant, and placing the centrifugal tube in a vacuum drying oven to constant weight (the drying temperature is 80 ℃, and the drying time is about 70min) to obtain the drug sustained-release anti-tumor nano robot.

The prepared drug sustained-release anti-tumor nano robot is observed by a transmission electron microscope (JEM-100SX transmission electron microscope, JEOL company, Japan), and the result shows that: most of the drug sustained-release antitumor nano-robots prepared by the embodiment are round and uniform spherical particles, the average particle size is 220nm, and no adhesion exists among the particles.

Evaluation of Effect

1) Tumor treatment

1.1) introduction of radio frequency heating technology and heating principle:

1.1.1) radio frequency heating technique: the tissue to be heated is placed between a pair of capacitance plates (the electrodes are not in contact with the human body), and radio frequency voltage is applied between the electrodes (capacitance field method), so that the tissue body between the capacitance plates absorbs electric field energy and converts the electric field energy into heat energy during thermotherapy, thereby raising the temperature of the tissue. Generally, the radio frequency band is 13.56MHz, and the power is 0-800W.

1.1.2) heating principle: the drug sustained-release anti-tumor nano robot absorbs electromagnetic wave energy under the action of an alternating magnetic field to generate vibration motion, paramagnetic metal fullerene particles contained in the nano robot generate heat due to hysteresis loss, and tumor tissues accumulated by the paramagnetic metal fullerene particles can also generate heat due to heat transfer. The tumor tissue has the advantages of distorted and expanded blood vessels, large blood resistance, unhealthy vascular receptors, poor temperature sensitivity, difficult heat dissipation under the action of high temperature, easy heat accumulation, quick temperature rise, formation of a huge heat storage reservoir, 5-10 ℃ temperature difference with normal tissue, and severe volume expansion of about 30-60% of paramagnetic metal fullerene particles contained in the nano robot. If the temperature of the tumor tissue is made to reach 43 ℃ or the tumor blood vessels burst, the tumor cells are overheated or cut off the nutrition to die.

1.2) tumor treatment procedure:

1mg of the drug-sustained release type antitumor nano-robot prepared in example 2 was diluted in physiological saline and then intravenously injected into a mouse. The nano-robots injected into the mouse body can automatically recognize tumor cells through the modified folic acid, and the nano-robots reach the tumor position and are clamped on the blood vessel wall for a long time after 30-60 min (due to the fact that the endothelial cells forming the tumor blood vessel have large gaps and incomplete structures, the tumor blood vessel usually comprises a large number of small holes with nanometer scales, small molecules and some nano-particles can enter through the through holes, and when the drug slow-release anti-tumor nano-robots pass through the gaps of the tumor blood vessel, the nano-robots can be tightly surrounded by the endothelial cells of the tumor blood vessel). After the surplus drug sustained-release type anti-tumor nano-robots are confirmed to flow away through CT scanning, the mice are subjected to radio frequency to detonate the drug sustained-release type anti-tumor nano-robots. After several minutes to dozens of minutes, the internal energy rises to generate phase change, and the volume is expanded by about 30-60% along with the intense expansion, the medicine slow-release anti-tumor nano robots inlaid on the walls of the tumor blood vessels explode to effectively destroy the tumor blood vessels, then quickly block the nutrition supply to the tumor, and completely starve the tumor cells within several hours.

1.3) evaluation of biocompatibility and degradation:

the nano robots prepared in examples 2 to 4 were used as test samples, respectively, the tumor treatment procedure of step 1.2) was performed, and then the biocompatibility and degradation condition of each test sample in vivo was identified by CT image, and the results are shown in table 1:

TABLE 1 biocompatibility and degradation of different test samples

As can be seen from the data in Table 1, the drug sustained-release anti-tumor nano robot is completely degraded or absorbed by a human body within 3-5 weeks after killing tumor cells, and has no side effect.

2) Other effects

The metal fullerene has excellent free radical scavenging effect and has the function of resisting oxidation damage and repairing various cells, so the nano robot provided by the invention can be used as a medicine and has good treatment effect on various diseases. In addition, the nano robot provided by the invention has a good drug slow release effect, and can consolidate the targeted treatment effect on tumor cells after the nano robot slowly releases the drug for 1-36 hours after entering the gaps of tumor blood vessels.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.