阅读说明：本技术 具有抗肿瘤功能的载药纳米机器人及其制备方法 (Drug-loaded nano robot with anti-tumor function 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,尤其涉及一种具有抗肿瘤功能的载药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：a)将磁性镁合金纳米颗粒、抗肿瘤药物、液态硬脂酸、挥发性有机溶剂和水进行混合,得到混合液；b)将所述混合液滴入液冷介质中,并搅拌挥去挥发性有机溶剂,得到混悬液；c)对所述混悬液进行离心分离,弃上清液,得到具有抗肿瘤功能的载药纳米机器人。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具有抗肿瘤功能的载药纳米机器人具有良好尺寸均匀性和可降解性,且可在外加磁场控制下准确到达肿瘤部位,实现对肿瘤的靶向治疗。(The invention belongs to the field of nano materials, and particularly relates to a drug-loaded nano robot with an anti-tumor function and a preparation method thereof. The preparation method provided by the invention comprises the following steps: a) mixing magnetic magnesium alloy nanoparticles, an anti-tumor drug, liquid stearic acid, a volatile organic solvent and water to obtain a mixed solution; b) dripping the mixed solution into a liquid cooling medium, and stirring to volatilize the volatile organic solvent to obtain a suspension; c) and carrying out centrifugal separation on the suspension, and discarding the supernatant to obtain the drug-loaded nano robot with the anti-tumor function. The preparation method provided by the invention has a stable production process, and the drug-loaded nano-robot with the anti-tumor function prepared by the method has good size uniformity and degradability, and can accurately reach the tumor part under the control of an external magnetic field to realize targeted therapy on the tumor.)

1. A preparation method of a drug-loaded nano robot with an anti-tumor function comprises the following steps:

a) mixing magnetic magnesium alloy nanoparticles, an anti-tumor drug, liquid stearic acid, a volatile organic solvent and water to obtain a mixed solution;

b) dripping the mixed solution into a liquid cooling medium, and stirring to volatilize the volatile organic solvent to obtain a suspension;

c) and carrying out centrifugal separation on the suspension, and discarding the supernatant to obtain the drug-loaded nano robot with the anti-tumor function.

2. The preparation method according to claim 1, wherein the chemical composition of the magnetic magnesium alloy particles in step a) comprises Nd, Zr, Fe, SiO₂Mn and Mg;

the particle size of the magnetic magnesium alloy particles is 80-100 nm.

3. The method according to claim 1, wherein in the step a), the magnetic magnesium alloy particles are prepared by the following steps:

i) carrying out solution treatment on the magnetic magnesium alloy to obtain a magnetic magnesium alloy solution;

ii) dripping the magnetic magnesium alloy molten liquid into a cold bath to obtain magnetic magnesium alloy nano particles.

4. The preparation method according to claim 1, wherein the antitumor drug in step a) comprises one or more of paclitaxel, dexamethasone, frogavidin, doxorubicin, docetaxel and doxorubicin.

5. The method according to claim 1, wherein the mixed solution further contains folic acid, graphene oxide, and a nonionic surfactant in step a).

6. The method of claim 5, wherein the non-ionic surfactant comprises one or more of Tween 80, Tween 20 and poloxamer.

7. The method as claimed in claim 1, wherein the temperature of the liquid cooling medium in step b) is-10 to 0 ℃.

8. The preparation method according to claim 1, wherein in the step b), the stirring speed is 100-300 r/min; the stirring time is 15-30 min.

9. The method according to claim 1, wherein in step c), the rotational speed of the centrifugal separation is 8000 to 10000 r/min; the centrifugal separation time is 15-30 min.

10. The drug-loaded nano robot with the anti-tumor function 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-loaded nano robot with an anti-tumor function 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 penetrate through the pores.

At present, many research institutes have developed novel tumor treatment schemes by utilizing the high permeability of tumor vessels to small molecules and nanoparticles, for example, a drug-loaded nano robot is used for treating tumors, and the drug-loaded nano robot refers to nanoparticles loaded with antitumor drugs. Research shows that the drug-loaded nano robot can effectively enrich the inside of a tumor after being injected into a human body by utilizing the high permeability of tumor blood vessels to nano particles, so that a good tumor treatment effect is obtained.

At present, most of researches of a drug-loaded nano robot in the field of tumor treatment still stay in an experimental stage, and the problems of poor stability of a preparation process of the nano robot, poor size uniformity of products, poor degradability, poor tumor treatment effect and the like exist, so that the application of the drug-loaded nano robot in the field of tumor treatment is seriously influenced.

Disclosure of Invention

In view of the above, the present invention aims to provide a drug-loaded nano-robot with an anti-tumor function and a preparation method thereof, the preparation method provided by the present invention has a stable production process, and the drug-loaded nano-robot with an anti-tumor function prepared by the method has good size uniformity and degradability, and can accurately reach a tumor part under the control of an external magnetic field, so as to realize targeted therapy on tumors.

The invention provides a preparation method of a drug-loaded nano robot with an anti-tumor function, which comprises the following steps:

a) mixing magnetic magnesium alloy nanoparticles, an anti-tumor drug, liquid stearic acid, a volatile organic solvent and water to obtain a mixed solution;

b) dripping the mixed solution into a liquid cooling medium, and stirring to volatilize the volatile organic solvent to obtain a suspension;

c) and carrying out centrifugal separation on the suspension, and discarding the supernatant to obtain the drug-loaded nano robot with the anti-tumor function.

Preferably, in step a), the chemical composition of the magnetic magnesium alloy particles comprises Nd, Zr, Fe, SiO₂Mn and Mg;

the particle size of the magnetic magnesium alloy particles is 80-100 nm.

Preferably, in step a), the magnetic magnesium alloy particles are prepared according to the following steps:

i) carrying out solution treatment on the magnetic magnesium alloy to obtain a magnetic magnesium alloy solution;

ii) dripping the magnetic magnesium alloy molten liquid into a cold bath to obtain magnetic magnesium alloy nano particles.

Preferably, in step a), the anti-tumor drug comprises one or more of paclitaxel, dexamethasone, frogspawn, doxorubicin, docetaxel and doxorubicin.

Preferably, in the step a), the mixed solution further contains folic acid, graphene oxide, and a nonionic surfactant.

Preferably, the non-ionic surfactant comprises one or more of tween 80, tween 20 and a poloxamer.

Preferably, in the step b), the temperature of the liquid cooling medium is-10 to 0 ℃.

Preferably, in the step b), the stirring speed is 100-300 r/min; the stirring time is 15-30 min.

Preferably, in the step c), the rotation speed of the centrifugal separation is 8000-10000 r/min; the centrifugal separation time is 15-30 min.

The invention provides a drug-loaded nano robot with an anti-tumor function, which is prepared by the preparation method according to the technical scheme.

Compared with the prior art, the invention provides a drug-loaded nano robot with an anti-tumor function and a preparation method thereof. The preparation method provided by the invention comprises the following steps: a) mixing magnetic magnesium alloy nanoparticles, an anti-tumor drug, liquid stearic acid, a volatile organic solvent and water to obtain a mixed solution; b) dripping the mixed solution into a liquid cooling medium, and stirring to volatilize the volatile organic solvent to obtain a suspension; c) and carrying out centrifugal separation on the suspension, and discarding the supernatant to obtain the drug-loaded nano robot with the anti-tumor function. Firstly, mixing magnetic magnesium alloy nanoparticles, an anti-tumor drug, liquid stearic acid and a solvent to prepare a mixed solution, then rapidly cooling the mixed solution, converting the stearic acid from a liquid state to a solid state in the rapid cooling process and adhering the magnetic magnesium alloy nanoparticles and the anti-tumor drug in the mixed solution to form a plurality of microspheres formed by the stearic acid, the magnetic magnesium alloy nanoparticles and the anti-tumor drug, and finally separating the microspheres by adopting a centrifugal separation mode to obtain the drug-loaded nano-robot with the anti-tumor function. According to the preparation method provided by the invention, the magnetic magnesium alloy nanoparticles are added into the nano robot, so that on one hand, the nano robot can show good magnetism, and can accurately reach a tumor part under the control of an external magnetic field, and the targeted therapy of the tumor is realized; on the other hand, the magnetic magnesium alloy nanoparticles can be completely degraded, so that the nano robot can show good degradability. The drug-loaded nano robot with the anti-tumor function prepared by the method provided by the invention has good size uniformity, magnetism and degradability, can efficiently kill tumor cells in a targeted manner, and can be completely degraded or absorbed by a human body after killing the tumor cells without any 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-loaded nano robot with an anti-tumor function, which comprises the following steps:

a) mixing magnetic magnesium alloy nanoparticles, an anti-tumor drug, liquid stearic acid, a volatile organic solvent and water to obtain a mixed solution;

b) dripping the mixed solution into a liquid cooling medium, and stirring to volatilize the volatile organic solvent to obtain a suspension;

c) and carrying out centrifugal separation on the suspension, and discarding the supernatant to obtain the drug-loaded nano robot with the anti-tumor function.

In the preparation method provided by the invention, the magnetic magnesium alloy nanoparticles, the anti-tumor drug, the liquid stearic acid, the volatile organic solvent and the water are mixed. Wherein the chemical composition of the magnetic magnesium alloy particles preferably comprises Nd, Zr, Fe and SiO₂Mn, Mg and Zr can obviously refine the crystal grains of the magnesium alloy; the content of Nd in the magnetic magnesium alloy particles is preferably 35 wt%, in particular 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt% or 5 wt%; the content of Zr in the magnetic magnesium alloy particles is preferably 15-20 wt%, and specifically can be 15 wt%, 15.5 wt%, 16 wt%, 16.5 wt%, 17 wt%, 17.5 wt%, 18 wt%, 18.5 wt%, 19 wt%, 19.5 wt% or 20 wt%; the content of Fe in the magnetic magnesium alloy particles is preferably 3-5 wt%, and specifically can be 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt% or 5 wt%; the SiO₂The content in the magnetic magnesium alloy particles is preferably 10 to 20 wt%, and specifically may be 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 15.5 wt%, 16 wt%, 16.5 wt%, 17 wt%, 17.5 wt%, 18 wt%, 18.5 wt%, 19 wt%, 19.5 wt%, or 20 wt%; the content of Mn in the magnetic magnesium alloy particles is preferably 3-5 wt%, and specifically can be 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt% or 5 wt%; the content of Mg in the magnetic magnesium alloy particles is preferably 50 to 66 wt%, and specifically may be 50 wt%, 51 wt%, 52 wt%, 53 wt%, 54 wt%, 55 wt%, 56 wt%, 57 wt%, 58 wt%, 59 wt%, 60 wt%, 61 wt%, 62 wt%, 63 wt%, 64 wt%, 65 wt%, or 66 wt%. In the present invention, the particle size of the magnetic magnesium alloy particle is preferably 80 to 100nm, and specifically may be 80nm, 81nm, 82nm, 83nm, 84nm, 85nm, 86nm, 87nm, 88nm, 89nm, 90nm, 91nm, 92nm, 93nm, 94nm, 95nm, 96nm, 97nm, 98nm, 99nm, or 100 nm. In the present invention, the magnetic magnesium alloy particles are preferably prepared according to the following steps:

i) carrying out solution treatment on the magnetic magnesium alloy to obtain a magnetic magnesium alloy solution;

ii) dripping the magnetic magnesium alloy molten liquid into a cold bath to obtain magnetic magnesium alloy nano particles.

In the preparation step of the magnetic magnesium alloy particles provided by the invention, the magnetic magnesium alloy is subjected to solution treatment at first. Wherein the temperature of the solution treatment is preferably 700-800 ℃, and specifically can be 700 ℃, 710 ℃, 720 ℃, 730 ℃, 740 ℃, 750 ℃, 760 ℃, 770 ℃, 780 ℃, 790 ℃ or 800 ℃; the time of the solution treatment is preferably 7-8 h, and specifically can be 7h, 7.1h, 7.2h, 7.3h, 7.4h, 7.5h, 7.6h, 7.7h, 7.8h, 7.9h or 8 h. And performing solution treatment on the magnetic magnesium alloy to obtain a magnetic magnesium alloy melt.

In the step of preparing the magnetic magnesium alloy particles provided by the invention, after the magnetic magnesium alloy melt is obtained, the magnetic magnesium alloy melt is dripped into a cold bath. Wherein the cold bath includes but is not limited to a liquid nitrogen bath, a liquid hydrogen bath, a dry ice acetone bath, a dry ice acetonitrile bath or a dry ice ethanol bath, preferably a liquid nitrogen bath; the dropping rate is preferably 0.5-1 mL/min, and specifically can be 0.5mL/min, 0.55mL/min, 0.6mL/min, 0.65mL/min, 0.7mL/min, 0.75mL/min, 0.8mL/min, 0.85mL/min, 0.9mL/min, 0.95mL/min or 1 mL/min; the volume ratio of the magnetic magnesium alloy melt to the cold bath is preferably 1: (50-80), specifically 1:50, 1:55, 1:60, 1:65, 1:70, 1:75 or 1: 80. In the invention, the magnetic magnesium alloy melt is dripped into the cold bath, so that the magnetic magnesium alloy melt can be rapidly cooled, the internal structure of metal in the magnetic magnesium alloy melt can be changed in the process, the metal can be rapidly converted from a liquid state to a solid state, and the metal is cracked into magnetic magnesium alloy nano particles in a powder state. In the invention, the size of the metal particles can be adjusted by controlling the Zr content of the magnetic magnesium alloy, the dropping speed of the magnetic magnesium alloy melt and the using amount of liquid nitrogen.

In the preparation step of the magnetic magnesium alloy particles, the magnetic magnesium alloy melt is dripped into a cold bath to form magnetic magnesium alloy nanoparticles, the magnetic magnesium alloy nanoparticles are allowed to stand in the cold bath for a period of time, the standing time is preferably 5-10 min, and then the magnetic magnesium alloy nanoparticles are separated from the cold bath to obtain dry magnetic magnesium alloy nanoparticles. The separation method is preferably to heat the cold bath directly to evaporate the cold bath.

In the preparation method provided by the invention, the anti-tumor drug includes but is not limited to one or more of Paclitaxel (PTX), Dexamethasone (DXM), saxabemycin, doxorubicin, docetaxel and doxorubicin; the stearic acid is in liquid state at the preparation temperature of more than 60 ℃, is degradable in vivo, has good biocompatibility and no toxicity to human body, and can make the medicament have slow release and controlled release after the stearic acid is cooled and solidified and is adhered with the antitumor medicamentAnd targeting; the volatile organic solvents include, but are not limited to, acetone; the mixed solution preferably further contains folic acid, graphene oxide and a nonionic surfactant; the folic acid can specifically react with a folic acid receptor on the cell surface to form a compound, the binding force of the folic acid and the folic acid receptor 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 graphene oxide has high porosity and large specific surface area, can improve the dispersibility of the antitumor drug and the magnetic magnesium alloy nanoparticles, the porosity of the graphene oxide is preferably 85-95%, specifically 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94% or 95%, and the specific surface area of the graphene oxide is preferably 2300-3000 m²A specific value of 2300m²/g、2350m²/g、2400m²/g、2450m²/g、2500m²/g、2550m²/g、2600m²/g、2650m²/g、2700m²/g、2750m²/g、2800m²/g、2850m²/g、2900m²/g、2950m²G or 3000m²The thickness of the graphene oxide is preferably 10-25 nm, and specifically can be 10nm, 11nm, 12nm, 13nm, 14nm, 15nm, 16nm, 17nm, 18nm, 19nm, 20nm, 21nm, 22nm, 23nm, 24nm or 25 nm; the nonionic surfactant mainly performs a modification and encapsulation effect on the surface of the nano-robot, and includes but is not limited to one or more of TWEEN 80(TWEEN 80), TWEEN 20(TWEEN 20) and poloxamer, and preferably TWEEN 80.

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 an organic solvent mixed system, namely a mixed system A;

heating and mixing stearic acid and water to obtain a mixed system of liquid stearic acid and water, which is called as a mixed system B;

II) mixing the mixed system A, the mixed system B and the magnetic magnesium alloy nanoparticles to obtain the mixed solution.

In the step of preparing the mixed solution provided in the above embodiment of the present invention, when the mixed system a is prepared, the content of the anti-tumor drug in the mixed system a is preferably 30 to 35 wt%, and specifically may be 30 wt%, 31 wt%, 32 wt%, 33 wt%, 34 wt%, or 35 wt%; the content of the volatile organic solvent in the mixed system a is preferably 45 to 60 wt%, and specifically may be 45 wt%, 46 wt%, 47 wt%, 48 wt%, 49 wt%, 50 wt%, 51 wt%, 52 wt%, 53 wt%, 54 wt%, 55 wt%, 56 wt%, 57 wt%, 58 wt%, 59 wt%, or 60 wt%. In the present invention, if the mixed solution further contains graphene oxide, the graphene oxide is added to the mixed system when preparing the mixed system a, and the content of the graphene oxide in the mixed system a is preferably 10 to 20 wt%, and specifically may be 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, or 20 wt%.

In the step of preparing the mixed solution provided in the above embodiment of the present invention, when preparing the mixed system a, it is preferable to first mix the antitumor drug and the volatile organic solvent to obtain a drug solution, and then mix the drug solution with the graphene oxide to obtain the mixed system a. The second mixing step is preferably carried out under the conditions of ultrasound and stirring, and the rotating speed of the stirring is preferably 200-300 r/min, and specifically can be 200r/min, 250r/min or 300 r/min.

In the mixed liquid preparation step provided in the above embodiment of the present invention, when preparing the mixed system B, the mass ratio of stearic acid to water is preferably (2 to 6): 6, specifically 2:6, 2.5:6, 3:6, 3.5:6, 4:6, 4.5:6, 5:6, 5.5:6 or 6: 6; the mixing temperature is preferably controlled to be a temperature at which stearic acid can be kept in a liquid state, and particularly can be controlled to be about 60 ℃; the mixing mode is preferably stirring mixing, the stirring speed of the stirring mixing is preferably 500-800 r/min, specifically 500r/min, 550r/min, 600r/min, 650r/min, 700r/min, 750r/min or 800r/min, and the time of the stirring mixing is preferably 60-120 min, specifically 60min, 70min, 80min, 90min, 100min, 110min or 120 min.

In the step of preparing the mixed solution provided in the above embodiment of the present invention, in the step II), the volume ratio of the mixed system a to the mixed system B is preferably (4 to 8): 3, specifically 4:3, 5:3, 6:3, 7:3 or 8: 3; the amount of the magnetic magnesium alloy nanoparticles is preferably 25 to 35 wt% of the total mass of the mixed system A and the mixed system B, and specifically may be 25 wt%, 26 wt%, 27 wt%, 28 wt%, 29 wt%, 30 wt%, 31 wt%, 32 wt%, 33 wt%, 34 wt% or 35 wt%. In the present invention, it is preferable that the mixed solution is obtained by mixing the mixed system a and the mixed system B first and then mixing them with the magnetic magnesium alloy nanoparticles. The mixing temperature of the mixed system A and the mixed system B is preferably controlled to be 60-65 ℃, the mixing mode is preferably stirring mixing, the stirring speed of the stirring mixing is preferably 400-500 r/min, specifically 400r/min, 450r/min or 500r/min, and the stirring mixing time is preferably 20-30 min, specifically 20min, 25min or 30 min; the mixing temperature with the magnetic magnesium alloy nanoparticles is preferably controlled to be 60-65 ℃, the mixing mode is preferably stirring mixing, the stirring speed of the stirring mixing is preferably 400-500 r/min, specifically 400r/min, 450r/min or 500r/min, and the stirring mixing time is preferably 10-15 min, specifically 10min, 12min or 15 min. In the present invention, if the mixed solution further contains folic acid and a nonionic surfactant, the folic acid and the nonionic surfactant are added to the mixed solution after the mixed solution a, the mixed solution B and the magnetic magnesium alloy particles are uniformly mixed. The mass-volume ratio of the folic acid to the mixed system B is preferably (0.5-2) g: 3mL, specifically 0.5 g: 3mL, 1 g: 3mL, 1.5 g: 3mL or 2 g: 3 mL; the volume ratio of the nonionic surfactant to the mixed system B is preferably (0.5-2): 3, specifically 0.5:3, 1:3, 1.5:3 or 2: 3; the continuous mixing mode is preferably stirring mixing, the stirring speed of the stirring mixing is preferably 100-200 r/min, specifically 100r/min, 150r/min or 200r/min, and the stirring mixing time is preferably 15-45 min, specifically 15min, 30min or 45 min; the initial temperature of the continuous mixing is preferably 55-59 ℃, and the termination temperature is preferably 35-45 ℃.

In the preparation method provided by the invention, after the mixed solution is obtained, the mixed solution is dripped into the liquid cooling medium, and the volatile organic solvent is stirred and volatilized to obtain the suspension. Wherein the dropping speed is preferably 5-20 mL/min, specifically 5mL/min, 6mL/min, 7mL/min, 8mL/min, 9mL/min, 10mL/min, 11mL/min, 12mL/min, 13mL/min, 14mL/min, 15mL/min, 16mL/min, 17mL/min, 18mL/min, 19mL/min or 20 mL/min; the liquid cooling medium is liquid which can still keep a flowing state at low temperature, and the temperature of the liquid cooling medium is preferably-10-0 ℃, and specifically can be-10 ℃, 9 ℃, 8 ℃, 7 ℃, 6 ℃, 5 ℃, 4 ℃, 3 ℃, 2 ℃, 1 ℃ or 0 ℃; the temperature of the system in the stirring process is preferably controlled at 5-10 ℃, and specifically can be 5 ℃, 5.5 ℃, 6 ℃, 6.5 ℃, 7 ℃, 7.5 ℃, 8 ℃, 8.5 ℃, 9 ℃, 9.5 ℃ or 10 ℃; the stirring speed is preferably 100-300 r/min, and specifically can be 100r/min, 120r/min, 150r/min, 180r/min, 200r/min, 230r/min, 250r/min, 270r/min or 300 r/min; the stirring time is preferably 15-30 min, and specifically can be 15min, 16min, 17min, 18min, 19min, 20min, 21min, 22min, 23min, 24min, 25min, 26min, 27min, 28min, 29min or 30 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 15-30 min, and specifically can be 15min, 18min, 20min, 23min, 25min, 27min or 30 min. And after the centrifugal separation is finished, removing the supernatant to obtain the drug-loaded nano robot with the anti-tumor function. In the invention, the surface of the prepared drug-loaded nano robot with the anti-tumor function can be better smooth and the compactness is better through centrifugal separation.

Firstly, mixing magnetic magnesium alloy nanoparticles, an anti-tumor drug, liquid stearic acid and a solvent to prepare a mixed solution, then rapidly cooling the mixed solution, converting the stearic acid from a liquid state to a solid state in the rapid cooling process and adhering the magnetic magnesium alloy nanoparticles and the anti-tumor drug in the mixed solution to form a plurality of microspheres formed by the stearic acid, the magnetic magnesium alloy nanoparticles and the anti-tumor drug, and finally separating the microspheres by adopting a centrifugal separation mode to obtain the drug-loaded nano-robot with the anti-tumor function. According to the preparation method provided by the invention, the magnetic magnesium alloy nanoparticles are added into the nano robot, so that on one hand, the nano robot can show good magnetism, and can accurately reach a tumor part under the control of an external magnetic field, and the targeted therapy of the tumor is realized; on the other hand, the magnetic magnesium alloy nanoparticles can be completely degraded, so that the nano robot can show good degradability. The drug-loaded nano robot with the anti-tumor function prepared by the method provided by the invention has good size uniformity, magnetism and degradability, can efficiently kill tumor cells in a targeted manner, and can be completely degraded or absorbed by a human body after killing the tumor cells without any 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-loaded nano robot with an anti-tumor function, which is prepared by adopting the method of the technical scheme. The drug-loaded nano robot with the anti-tumor function has good size uniformity, magnetism and degradability, can efficiently kill tumor cells in a targeted manner, can be completely degraded or absorbed by a human body after killing the tumor cells, and has no side effect, so that the drug-loaded nano robot with the anti-tumor function has wide application prospect in the field of tumor treatment.

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

Example 1

1) Preparing magnetic magnesium alloy nanoparticles:

1.1) carrying out solution treatment on the magnetic magnesium alloy for 7.5h at 750 ℃ to obtain a magnetic magnesium alloy melt. The magnetic magnesium alloy comprises the following chemical components: nd 4 wt%, Zr 17 wt%, Fe 4 wt%, SiO₂12 wt%, Mn 4 wt%, and the balance Mg.

1.2) dripping 1mL of magnetic magnesium alloy melt into 70mL of liquid nitrogen, wherein the dripping speed is controlled at 0.7 mL/min; and standing for 5-10 min after the dropwise addition is finished, then heating the system to 30 ℃, and vaporizing and volatilizing liquid nitrogen in the heating process to obtain dry magnetic magnesium alloy nanoparticles with the particle diameter of 80-100 nm.

2) The preparation of the drug-loaded nano robot with the anti-tumor function comprises the following steps:

2.1) dissolving paclitaxel in acetone, stirring for 10-15 min until the paclitaxel is completely dissolved, then adding graphene oxide, and stirring while performing ultrasonic treatment at a stirring speed of 200r/min to obtain a mixed system A. Wherein the graphite oxide has a porosity of 90% and a specific surface area of 2800m²The thickness is 15nm, and in the mixed system A, the content of paclitaxel is 30 wt%, the content of acetone is 60 wt%, and the content of graphene oxide is 10 wt%.

2.2) preparing a certain amount of purified water, heating to 60-70 ℃, adding stearic acid (the mass ratio of the purified water to the stearic acid is 6:4), stirring for 60min at a stirring speed of 500r/min, and maintaining the temperature at 58-61 ℃ during stirring to obtain a mixed system B.

2.3) slowly pouring the mixed system A into the mixed system B, continuously stirring at the speed of 400r/min, controlling the stirring temperature at 60-65 ℃, stirring for 20min, then adding the magnetic magnesium alloy nanoparticles prepared in the step 1), continuously stirring at the speed of 400r/min for 15min, then reducing the temperature of the mixed system to 55-59 ℃, adding folic acid and tween 80, continuously stirring at the speed of 150r/min for 30min, and reducing the temperature of the mixed system to 35-45 ℃ after the stirring is finished. Wherein the dosage ratio of the mixed system A to the mixed system B to the folic acid to the Tween 80 is 5 (mL): 3 (mL): 1 (g): 1(mL), and the dosage of the magnetic magnesium alloy nano particles is 30 wt% of the total mass of the mixed system A and the mixed system B.

2.4) quickly dropping the mixed solution prepared in the step 2.3) into a liquid cooling medium (ice water mixed with an antifreezing agent at the temperature of minus 10 ℃) at the dropping speed of 13mL/min, and then continuously stirring to volatilize the organic solvent to obtain a suspension. Wherein the stirring speed is 200r/min, the stirring time is 30min, and the system temperature is controlled to be about 5 ℃ in the stirring process.

2.5) placing the suspension prepared in the step 2.4) in a centrifuge tube, centrifuging at 9000r/min for 15min to obtain the drug-loaded nano robot with the anti-tumor function.

The prepared drug-loaded nano-robot with the anti-tumor function is observed by a transmission electron microscope (JEM-100SX transmission electron microscope, JEOL company, Japan), and the result shows that: the drug-loaded nano-robot with the anti-tumor function prepared by the embodiment is mostly round and uniform spherical particles, is free of adhesion and has the diameter of 150-200 nm.

Example 2

1) Preparing magnetic magnesium alloy nanoparticles:

1.1) carrying out solution treatment on the magnetic magnesium alloy for 7.5h at 750 ℃ to obtain a magnetic magnesium alloy melt. The magnetic magnesium alloy comprises the following chemical components: nd 3 wt%, Zr 15 wt%, Fe 3 wt%, SiO₂10 wt%, Mn 3 wt%, and the balance Mg.

1.2) dripping 1mL of magnetic magnesium alloy melt into 70mL of liquid nitrogen, wherein the dripping speed is controlled at 0.5 mL/min; and standing for 5-10 min after the dropwise addition is finished, then heating the system to 30 ℃, and vaporizing and volatilizing liquid nitrogen in the heating process to obtain dry magnetic magnesium alloy nanoparticles with the particle diameter of 80-100 nm.

2) The preparation of the drug-loaded nano robot with the anti-tumor function comprises the following steps:

2.1) dissolving paclitaxel in acetone, stirring for 10-15 min until the paclitaxel is completely dissolved, then adding graphene oxide, and stirring while performing ultrasonic treatment at a stirring speed of 200r/min to obtain a mixed system A. Wherein the graphite oxide has a porosity of 85% and a specific surface area of 2500m²The thickness is 10nm, and in the mixed system A, the content of paclitaxel is 30 wt%, the content of acetone is 60 wt%, and the content of graphene oxide is 10 wt%.

2.2) preparing a certain amount of purified water, heating to 60-70 ℃, adding stearic acid (the mass ratio of the purified water to the stearic acid is 6:4), stirring for 60min at a stirring speed of 500r/min, and maintaining the temperature at 58-61 ℃ during stirring to obtain a mixed system B.

2.3) slowly pouring the mixed system A into the mixed system B, continuously stirring at the speed of 400r/min, controlling the stirring temperature at 60-65 ℃, stirring for 20min, then adding the magnetic magnesium alloy nanoparticles prepared in the step 1), continuously stirring at the speed of 400r/min for 15min, then reducing the temperature of the mixed system to 55-59 ℃, adding folic acid and tween 80, continuously stirring at the speed of 150r/min for 30min, and reducing the temperature of the mixed system to 35-45 ℃ after the stirring is finished. Wherein the dosage ratio of the mixed system A to the mixed system B to the folic acid to the Tween 80 is 5 (mL): 3 (mL): 1 (g): 1(mL), and the dosage of the magnetic magnesium alloy nano particles is 25 wt% of the total mass of the mixed system A and the mixed system B.

2.4) quickly dropping the mixed solution prepared in the step 2.3) into a liquid cooling medium (ice water mixed with an antifreezing agent at the temperature of minus 10 ℃), wherein the dropping speed is 10mL/min, and then continuously stirring to volatilize the organic solvent to obtain a suspension. Wherein the stirring speed is 200r/min, the stirring time is 30min, and the system temperature is controlled to be about 5 ℃ in the stirring process.

2.5) placing the suspension prepared in the step 2.4) in a centrifuge tube, centrifuging at 9000r/min for 15min to obtain the drug-loaded nano robot with the anti-tumor function.

The prepared drug-loaded nano-robot with the anti-tumor function is observed by a transmission electron microscope (JEM-100SX transmission electron microscope, JEOL company, Japan), and the result shows that: the drug-loaded nano-robot with the anti-tumor function prepared by the embodiment is mostly round and uniform spherical particles, is free of adhesion and has the diameter of 150-200 nm.

Example 3

1) Preparing magnetic magnesium alloy nanoparticles:

1.1) carrying out solution treatment on the magnetic magnesium alloy for 7.5h at 750 ℃ to obtain a magnetic magnesium alloy melt. The magnetic magnesium alloy comprises the following chemical components: nd 5 wt%, Zr 20 wt%, Fe 5 wt%, SiO₂15 wt%, Mn 5 wt%, and the balance Mg.

1.2) dripping 1mL of magnetic magnesium alloy melt into 70mL of liquid nitrogen, wherein the dripping speed is controlled at 1 mL/min; and standing for 5-10 min after the dropwise addition is finished, then heating the system to 30 ℃, and vaporizing and volatilizing liquid nitrogen in the heating process to obtain dry magnetic magnesium alloy nanoparticles with the particle diameter of 80-100 nm.

2) The preparation of the drug-loaded nano robot with the anti-tumor function comprises the following steps:

2.1) dissolving paclitaxel in acetone, stirring for 10-15 min until the paclitaxel is completely dissolved, then adding graphene oxide, and stirring while performing ultrasonic treatment at a stirring speed of 200r/min to obtain a mixed system A. Wherein the graphite oxide has a porosity of 95% and a specific surface area of 3000m²The thickness is 25nm, and in the mixed system A, the content of paclitaxel is 30 wt%, the content of acetone is 60 wt%, and the content of graphene oxide is 10 wt%.

2.2) preparing a certain amount of purified water, heating to 60-70 ℃, adding stearic acid (the mass ratio of the purified water to the stearic acid is 6:4), stirring for 60min at a stirring speed of 500r/min, and maintaining the temperature at 58-61 ℃ during stirring to obtain a mixed system B.

2.3) slowly pouring the mixed system A into the mixed system B, continuously stirring at the speed of 400r/min, controlling the stirring temperature at 60-65 ℃, stirring for 20min, then adding the magnetic magnesium alloy nanoparticles prepared in the step 1), continuously stirring at the speed of 400r/min for 15min, then reducing the temperature of the mixed system to 55-59 ℃, adding folic acid and tween 80, continuously stirring at the speed of 150r/min for 30min, and reducing the temperature of the mixed system to 35-45 ℃ after the stirring is finished. Wherein the dosage ratio of the mixed system A to the mixed system B to the folic acid to the Tween 80 is 5 (mL): 3 (mL): 1 (g): 1(mL), and the dosage of the magnetic magnesium alloy nano particles is 35 wt% of the total mass of the mixed system A and the mixed system B.

2.4) quickly dropping the mixed solution prepared in the step 2.3) into a liquid cooling medium (ice water mixed with an antifreezing agent at the temperature of minus 10 ℃) at a dropping speed of 15mL/min, and then continuously stirring to volatilize the organic solvent to obtain a suspension. Wherein the stirring speed is 200r/min, the stirring time is 30min, and the system temperature is controlled to be about 5 ℃ in the stirring process.

2.5) placing the suspension prepared in the step 2.4) in a centrifuge tube, centrifuging at 9000r/min for 15min to obtain the drug-loaded nano robot with the anti-tumor function.

The prepared drug-loaded nano-robot with the anti-tumor function is observed by a transmission electron microscope (JEM-100SX transmission electron microscope, JEOL company, Japan), and the result shows that: the drug-loaded nano-robot with the anti-tumor function prepared by the embodiment is mostly round and uniform spherical particles, is free of adhesion and has the diameter of 150-200 nm.

Evaluation of Effect

Diluting 1mg of the drug-loaded nano-robot with the anti-tumor function prepared in the above embodiment into saline, injecting the saline into a tumor region of a patient, completely covering the tumor region (the range of the nano-robot exceeds the tumor range by more than 5mm and is defined as complete coverage) with the drug-loaded nano-robot with the anti-tumor function through the high selectivity of folic acid on tumors or an external magnetic control system, and finally identifying the biocompatibility and degradation condition of the drug-loaded nano-robot with the anti-tumor function in vivo through images such as CT (computed tomography), wherein the results are shown in Table 1:

TABLE 1 biocompatibility and degradation of different test samples

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.