Drug loading and delivering method and cell carrying method of core-shell mesoporous micro-nano robot

Abstract

The invention relates to the technical field of targeted cargo delivery, in particular to a drug loading and delivery method and a cell carrying method of a core-shell mesoporous micro-nano robot. The drug loading and delivery method is realized based on the drug loading capacity of the mesoporous structure, the magnetism of the iron oxide core and the photothermal effect of the polydopamine shell. The core-shell mesoporous micro-nano robot can adsorb and load drugs through capillary force and electrostatic force generated by the mesoporous structure of the core-shell mesoporous micro-nano robot; then, an external magnetic field is used for driving the device to move; near-infrared light is utilized to irradiate when approaching a targeted area, the temperature of a pore structure rises, and along with thermal vibration, drugs in mesopores are effectively released to the targeted area, so that the drug delivery effect is achieved. When the drug is loaded and delivered, the core-shell mesoporous micro-nano robot has carrying capacity after being clustered under a magnetic field, and cells are carried through an eddy current carrying method and a contact adhesion method. Targeted goods delivery of goods such as targeted drugs and cells can be achieved through the micro-nano robot.

Description

Technical Field

[0001] The present invention relates to the technical field of targeted cargo delivery, and more specifically, to a drug loading and delivery method and a cell carrying method for core-shell mesoporous micro-nanorobots. Background Art

[0002] Precision medicine, as the core research field of medicine in the 21st century, has become a key development technology at the strategic level in various countries around the world. Targeted cargo delivery is the core of precision medicine. The types of cargo delivered by targeted cargo delivery technology include both targeted drugs such as doxorubicin and functional cells such as T cells and red blood cells used in cell therapy. With the continuous breakthrough of medical technology bottlenecks, targeted cargo delivery technology will bring new core driving forces to precision medicine and promote the development of precision medicine. Micro-nanorobots are an emerging frontier technology with characteristics such as small size, good controllability, and large thrust-to-weight ratio. They can convert external physical field energy into mechanical energy for their own movement, and have outstanding advantages in the biomedical field, and can bring new breakthrough ideas to targeted cargo delivery technology. However, in the existing technology, there is no technology for realizing targeted cargo delivery through micro-nanorobots. This technological gap limits the further development of targeted cargo delivery technology, and also poses new challenges and opportunities for scientific researchers. If micro-nanorobots can be innovatively applied to targeted cargo delivery, it is expected to bring new core driving forces to precision medicine and promote its leapfrog development. Summary of the Invention

[0003] To overcome the deficiencies of the prior art, the present invention provides a core-shell mesoporous micro-nanorobot for targeted cargo delivery, and proposes a drug loading and delivery method and a cell carrying method based on the core-shell mesoporous micro-nanorobot. The beneficial effect is that targeted cargo delivery of cargo such as targeted drugs and cells can be realized through micro-nanorobots.

[0004] The technical solution adopted by the present invention to solve its technical problems is:

[0005] A drug loading and delivery method for a core-shell mesoporous micro-nanorobot, the drug loading and delivery method is realized based on the drug loading capacity of its mesoporous structure, the magnetism of the iron oxide core, and the photothermal effect of the polydopamine shell;

[0006] First, the core-shell mesoporous micro-nanorobot can adsorb and load drugs through the capillary force and electrostatic force generated by its mesoporous structure;

[0007] Subsequently, an external magnetic field is used to drive its movement;

[0008] When approaching the target area, near-infrared light is used for irradiation. Since polydopamine can generate a photothermal effect under the irradiation of near-infrared light, the temperature of the pore structure rises and is accompanied by thermal vibration, effectively releasing the drug in the mesopores to the target area and achieving the drug delivery effect.

[0009] A method for transporting cells by a core-shell mesoporous micro-nanorobot. While loading and delivering drugs, the core-shell mesoporous micro-nanorobot has a transport capacity after clustering under a magnetic field, and transports cells by two methods: eddy current carrying and contact adhesion.

[0010] The method of eddy current carrying is as follows:

[0011] First, the iron oxide magnetic core of the core-shell mesoporous micro-nanorobot has paramagnetism and rotates stably under the uniform rotating magnetic field generated by the Helmholtz coil, generating small eddy currents around it. Under the gravitational force generated by the eddy currents and the gravitational force generated after the magnetization of the magnetic iron oxide core, the micro-nanorobots form an aggregate, and due to the viscosity of the polydopamine surface, the aggregate structure is stable;

[0012] Under the drive of the magnetic field, the aggregate of the core-shell mesoporous micro-nanorobots rolling at high speed generates a rotating eddy current. The gravitational force generated by the eddy current attracts and carries the cells to move. After reaching the target area, the cells are released by adjusting the external magnetic field parameters to reduce the rotation speed.

[0013] The method of contact adhesion is as follows:

[0014] The aggregate of the core-shell mesoporous micro-nanorobots uses surface hydrophilicity and viscosity to adhere to the cells, and then carries the cells to move under the drive of the magnetic field. After reaching the target area, the cells are released by adjusting the external magnetic field direction to become horizontal rotation, making the aggregate rotate horizontally.

[0015] A core-shell mesoporous micro-nanorobot for targeted cargo delivery, which consists of two parts: a magnetic core composed of iron oxide and a mesoporous shell composed of polydopamine. The mesoporous shell composed of polydopamine is arranged outside the magnetic core composed of iron oxide.

[0016] A drive control device for a core-shell mesoporous micro-nanorobot for targeted cargo delivery, the drive control device includes two parts: a magnetic field generating device and an infrared light field generating device;

[0017] The magnetic field generating device is a three-dimensional Helmholtz coil. The signal generator generates a sine electrical signal and inputs it into the Helmholtz coil after being amplified by the power amplifier. By changing the phase and amplitude of the electrical signal to adjust the magnetic field intensity generated by the three pairs of coils and combining them, a uniform rotating magnetic field in any direction in space is generated. The uniform rotating magnetic field includes a forward rolling rotation mode and a horizontal rotation mode. Under the drive of the Helmholtz coil, the core-shell mesoporous micro-nanorobot rolls in any direction to move and cluster;

[0018] The infrared light field generating device is an infrared laser generator, which can emit near-infrared light with a wavelength of 808 nm at a fixed power to excite the core-shell mesoporous micro-nanorobot to generate a photothermal effect, and the intensity of the irradiated infrared light can be adjusted by regulating the power through a controller.

[0019] A preparation process of a core-shell mesoporous micro-nanorobot for targeted cargo delivery includes the preparation of a sol-gel magnetic core and the preparation of a chemically synthesized mesoporous shell.

[0020] In the process of preparing the sol-gel magnetic core, ferric chloride reacts with sodium hydroxide to form ferric hydroxide colloid, and the ferric hydroxide colloid seeds are heated in an environment containing sodium sulfate to transform into iron oxide and gradually grow, growing from the initial seed state into a spindle shape and finally into an ellipsoidal iron oxide magnetic core.

[0021] In the process of preparing the chemically synthesized mesoporous shell, due to the hydrophilicity of the surface of the iron oxide magnetic core and the electrostatic interaction, dopamine nanoparticle seeds gradually aggregate and grow on its surface in an alkaline environment.

[0022] In addition, due to the poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymer, that is, P123, affecting the aggregation degree of dopamine on the surface of the magnetic core, a poly(dopamine) shell with a mesoporous structure will be generated on the surface of the iron oxide core.

[0023] Finally, a core-shell mesoporous micro-nanorobot wrapped with poly(dopamine) is obtained.

[0024] The porosity of the mesoporous shell of the core-shell mesoporous micro-nanorobot is adjusted by changing the dosages of ammonia water and P123 in the preparation of the chemically synthesized mesoporous shell.

[0025] In the synthesis process of the poly(dopamine) mesoporous shell, the aggregation degree of P123 on dopamine is affected by the acidity and alkalinity of the environment. The increase in the ammonia water concentration leads to an increase in the alkalinity of the solution, resulting in a denser mesoporous structure; in addition, as the concentration of P123 in the solution decreases, dopamine will closely aggregate and grow on the surface of the core to form nano-scale radial mesopores.

[0026] The beneficial effects of the drug loading and delivery method and cell transportation method of the core-shell mesoporous micro-nanorobot of the present invention are as follows:

[0027] The prepared poly(dopamine) / iron oxide core-shell mesoporous micro-nanorobot can respond to an external magnetic field, convert the magnetic energy of the external magnetic field into the mechanical energy of its own movement, and move. By controlling the rotation magnetic field intensity, direction and frequency of the three-dimensional Helmholtz coil, precise control of the movement of the poly(dopamine) / iron oxide core-shell mesoporous micro-nanorobot can be achieved.

[0028] The prepared polydopamine / iron oxide core-shell mesoporous micro-nanorobots can be loaded with drugs through the surface mesoporous structure;

[0029] The porosity of the polydopamine shell of the prepared polydopamine / iron oxide core-shell mesoporous micro-nanorobots can be stably adjusted, enriching the diversity of their drug loading;

[0030] The prepared polydopamine / iron oxide core-shell mesoporous micro-nanorobots can generate a photothermal effect in response to infrared light through the surface polydopamine structure for drug release;

[0031] The prepared polydopamine / iron oxide core-shell mesoporous micro-nanorobots can cluster in a magnetic field and form a stable aggregate;

[0032] After the polydopamine / iron oxide core-shell mesoporous micro-nanorobots form an aggregate, they can load and transport cells through the eddy current portable cell transport method. This non-contact transport method is fast, flexible in movement, and has no damage to cells;

[0033] After the polydopamine / iron oxide core-shell mesoporous micro-nanorobots form an aggregate, they can load and transport cells through the contact adhesion cell transport method. This contact transport method has good loading and transport stability, strong resistance to flow field interference, and can perform long-distance transport;

[0034] The polydopamine / iron oxide core-shell mesoporous micro-nanorobots integrate drug loading and delivery with cell transport capabilities, can meet various application requirements simultaneously, bring new ideas for the design of carriers for drug delivery and cell manipulation, and will have broad application prospects in the field of biomedicine. Brief Description of the Drawings

[0035] The following further elaborates on the present invention in detail in conjunction with the drawings and specific implementation methods.

[0036] Figure 1 It is a process mechanism diagram for the preparation of core-shell mesoporous micro-nanorobots;

[0037] Figure 2 It is a process flow diagram for the preparation of core-shell mesoporous micro-nanorobots;

[0038] Figure 3 It is a scanning electron microscope image and energy spectrum diagram of core-shell mesoporous micro-nanorobots;

[0039] Figure 4 It is a scanning electron microscope image of the porosity adjustment of core-shell mesoporous micro-nanorobots;

[0040] Figure 5 It is a transmission electron microscope image of core-shell mesoporous micro-nanorobots;

[0041] Figure 6For the drug loading light absorption curve and fluorescence image of the core-shell mesoporous micro-nanorobot;

[0042] Figure 7 For the mechanism and experimental diagram of the core-shell mesoporous micro-nanorobot cluster;

[0043] Figure 8 For the mechanism and experimental diagram of the core-shell mesoporous micro-nanorobot's eddy current portable cell transportation;

[0044] Figure 9 For the mechanism and experimental diagram of the core-shell mesoporous micro-nanorobot's contact adhesion cell transportation. Specific implementation manner

[0045] The present invention proposes a poly-dopamine / iron oxide core-shell mesoporous micro-nanorobot with adjustable porosity. Based on the paramagnetism of its iron oxide magnetic core, this core-shell micro-nanorobot can be driven and clustered under a magnetic field; based on the mesoporous structure of its poly-dopamine shell, the core-shell micro-nanorobot can be used as a carrier for targeted drugs; based on the viscosity of its poly-dopamine shell, the core-shell micro-nanorobot can be used as a carrier for cells by adhering to cells for targeted transportation. This poly-dopamine / iron oxide core-shell mesoporous micro-nanorobot that integrates the functions of targeted drug loading and delivery and cell transportation provides a new idea for the carrier design of targeted cargo delivery technology, promotes the deep integration of biomedicine and materials science, and will significantly promote the development of precision medicine technology.

[0046] The preparation of the poly-dopamine / iron oxide core-shell mesoporous micro-nanorobot includes two-step processes, as Figure 1 shown. The specific process flow of the sol-gel magnetic core preparation is as follows: slowly drip sodium hydroxide solution (90 mL, 5 mol / L) into ferric chloride solution (100 mL, 2 mol / L), stir with a mechanical stirrer for 10 minutes, add sodium sulfate solution (10 mL, 0.3 mol / L), stir with a mechanical stirrer for 10 minutes, transfer the stirred solution to a glass bottle (250 mL), heat it in a muffle furnace at 100 °C for 8 days, wash and centrifuge the obtained solution 4 times with absolute ethanol, further wash and centrifuge the obtained solution 4 times with deionized water, and place the obtained solution in a drying oven at 60 °C - 90 °C (preferably 80 °C) for drying for 8 - 16 (preferably 12) hours to obtain the iron oxide core.

[0047] The specific process flow for the preparation of chemically synthesized mesoporous shells is as follows: Add iron oxide cores (20 mg), dopamine hydrochloride (0.2 g), poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymer (P123) (35 mg), and poly(oxyethylene)-poly(oxypropylene) (F127) (75 mg) into a conical flask, then add anhydrous ethanol (7.5 ml) and deionized water (7.5 ml). Ultrasonically treat the resulting dispersion for 5 - 15 minutes. Add 1,3,5-trimethylbenzene (0.6 ml) to the resulting homogeneous dispersion and ultrasonically treat it for 10 - 20 minutes. Magnetically stir the dispersion, and during the stirring process, add ammonia water (0.3 mL, 28%) and magnetically stir at room temperature for 2 - 4 hours. Wash the resulting solution with anhydrous ethanol and centrifuge it 4 times, and further wash and centrifuge the resulting solution with deionized water 4 times. Place the resulting solution in an oven and dry it at 60°C - 90°C (preferably 80°C) for 8 - 16 (preferably 12) hours to obtain polydopamine / iron oxide core-shell mesoporous micro-nanorobots, as Figure 2 shown. The scanning electron microscope image and energy spectrum diagram of the polydopamine / iron oxide core-shell mesoporous micro-nanorobots are as Figure 3 shown.

[0048] The scanning electron microscope image and transmission electron microscope image of the porosity adjustment of the polydopamine / iron oxide core-shell mesoporous micro-nanorobots are as Figure 4 、 Figure 5 shown. The amounts of ammonia water added from the first to the third from the left are 0.2 ml, 0.35 ml, and 0.5 ml respectively.

[0049] The experimental process for drug loading and delivery is as follows: First, disperse the polydopamine / iron oxide core-shell mesoporous micro-nanorobots in phosphate buffer solution, take out the doxorubicin phosphate buffer solution with a concentration of 1 mg / ml and mix it in a volume ratio of 1:1, and place it in a dark environment for stirring for 48 hours. Subsequently, wash and centrifuge the drug-loaded polydopamine mesoporous micro-nanorobots with phosphate buffer solution 3 times, and disperse them again in phosphate buffer solution. The light absorption data graphs of the polydopamine / iron oxide core-shell mesoporous micro-nanorobots before and after drug loading are as Figure 6 (a) shown. After dispersing the drug-loaded polydopamine / iron oxide core-shell mesoporous micro-nanorobots in phosphate buffer solution, place them in a Helmholtz coil. The Helmholtz coil selects the forward rolling and rotating mode, and the magnetic field parameters are 10 mT and 15 Hz. The polydopamine / iron oxide core-shell mesoporous micro-nanorobots rotate in response to external magnetic field changes. After reaching the target area, adjust the 808 nm near-infrared light field parameters to 6 W / cm2 and turn on the light field for irradiation, and then perform fluorescence observation. The fluorescence image of the polydopamine / iron oxide core-shell mesoporous micro-nanorobots is as Figure 6 (b) shown.

[0050] Cluster process experimental procedure: The Helmholtz coil is selected to operate in the forward rolling rotation mode with magnetic field parameters of 10 mT and 15 Hz. The polydopamine / iron oxide core-shell mesoporous micro-nanorobots can respond to external magnetic field changes and perform stable rotational motion under these parameters. During the rotation process, they cluster to obtain a population of polydopamine / iron oxide core-shell mesoporous micro-nanorobots, as Figure 7 shown.

[0051] The experimental procedure for eddy current portable cell transportation is as follows: Centrifuge and disperse red blood cells in phosphate buffer to prepare a dispersion. Add the dispersion to a petri dish and place it inside the Helmholtz coil. Then, add the polydopamine / iron oxide core-shell mesoporous micro-nanorobots dispersed in phosphate buffer to the phosphate buffer containing red blood cells. The Helmholtz coil is selected to operate in the forward rolling rotation mode with magnetic field parameters of 10 mT and 15 Hz. Obtain a population of micro-nanorobots through clustering, drive the population of micro-nanorobots to move. After approaching the target red blood cells, the Helmholtz coil maintains the forward rolling rotation mode, and the magnetic field parameters are adjusted to 10 mT and 35 Hz. Use eddy current to carry the cells for transportation. After reaching the designated area, the magnetic field parameters are adjusted to 10 mT and 15 Hz to release the cells, as Figure 8 shown.

[0052] The experimental procedure for contact adhesion cell transportation is as follows: Centrifuge and disperse red blood cells in phosphate buffer to prepare a dispersion. Add the dispersion to a petri dish and place it inside the Helmholtz coil. Then, add the polydopamine / iron oxide core-shell mesoporous micro-nanorobots dispersed in phosphate buffer to the phosphate buffer containing red blood cells. The Helmholtz coil is selected to operate in the forward rolling rotation mode with magnetic field parameters of 10 mT and 15 Hz. Obtain a population of micro-nanorobots through clustering, drive the population of micro-nanorobots to move. After locking on the target red blood cells, drive the population of micro-nanorobots to approach the cells, so that the population of polydopamine mesoporous micro-nanorobots contacts and adheres to the red blood cells. After observing the adhesion, the Helmholtz coil maintains the forward rolling rotation mode with magnetic field parameters of 10 mT and 15 Hz for cell transportation. After reaching the designated area, the Helmholtz coil switches to the horizontal rotation mode with magnetic field parameters of 10 mT and 25 Hz, and the population of micro-nanorobots rotates horizontally to release the cells, ending the experiment, as Figure 9 shown.

Claims

1. A method for drug loading and delivery of core-shell mesoporous micro-nano robots, characterized in that: The drug loading and delivery method is realized based on the drug loading capacity of its mesoporous structure, the magnetism of the iron oxide core, and the photothermal effect of the polydopamine shell; First, the core-shell mesoporous micro-nanorobot can adsorb and load drugs through the capillary force and electrostatic force generated by its mesoporous structure; Subsequently, an external magnetic field is used to drive its movement; When approaching the target area, near-infrared light is used for irradiation. Since polydopamine can generate a photothermal effect under the irradiation of near-infrared light, the temperature of the pore structure increases and is accompanied by thermal vibration, effectively releasing the drugs in the mesopores to the target area to achieve the drug delivery effect.

2. A method for cell delivery of a core-shell mesoporous micro-nano robot, characterized in that: During drug loading and delivery, the core-shell mesoporous micro-nanorobots have a carrying capacity after clustering under the magnetic field, and carry cells through two methods: eddy current carrying type and contact adhesion type.

3. The method for cell delivery of a core-shell mesoporous micro-nano robot according to claim 2, characterized in that: The method of the eddy current carrying type is as follows: First, the iron oxide magnetic core of the core-shell mesoporous micro-nanorobot has paramagnetism and rotates stably under the uniform rotating magnetic field generated by the Helmholtz coil, generating small eddy currents around it. Under the gravitational force generated by the eddy currents and the gravitational force generated after the magnetization of the magnetic iron oxide core, the micro-nanorobots form an aggregate, and due to the viscosity of the polydopamine surface, the aggregate structure is stable; Under the drive of the magnetic field, the rotating eddy currents are generated by the aggregate of the core-shell mesoporous micro-nanorobots rolling at high speed. The gravitational force generated by the eddy currents attracts and carries cells to move. After reaching the target area, the cells are released by adjusting the external magnetic field parameters to reduce the rotation speed.

4. The cell delivery method of a core-shell mesoporous micro-nano robot according to claim 2, wherein: The method of the contact adhesion type is as follows: The aggregate of the core-shell mesoporous micro-nanorobots uses surface hydrophilicity and viscosity to adhere to cells, and then carries the cells to move under the drive of the magnetic field. After reaching the target area, the cells are released by adjusting the external magnetic field direction to become horizontal rotation, causing the aggregate to rotate horizontally.

5. A core-shell mesoporous micro-nanorobot for targeted cargo delivery, characterized in that: It consists of two parts: a magnetic core composed of iron oxide and a mesoporous shell composed of polydopamine. The mesoporous shell composed of polydopamine is arranged outside the magnetic core composed of iron oxide.

6. The drive control device of a core-shell mesoporous micro-nanorobot for targeted cargo delivery according to claim 5, characterized in that: The drive control device includes two parts: a magnetic field generating device and an infrared light field generating device; The magnetic field generating device is a three-dimensional Helmholtz coil. The signal generator generates a sinusoidal electrical signal and inputs it into the Helmholtz coil after being amplified by a power amplifier. By changing the phase and amplitude of the electrical signal, the magnetic field intensities generated by the three pairs of coils are adjusted and combined to generate a uniform rotating magnetic field in any direction in space. The uniform rotating magnetic field includes a forward rolling rotation mode and a horizontal rotation mode. Under the drive of the Helmholtz coil, the core-shell mesoporous micro-nanorobots roll and move in any direction and cluster; The infrared light field generating device is an infrared laser generator. The infrared laser generator can emit near-infrared light with a wavelength of 808 nm at a fixed power to stimulate the core-shell mesoporous micro-nanorobots to generate a photothermal effect, and the intensity of the irradiated infrared light is adjusted by the controller to adjust the power.

7. Preparation process of a core-shell mesoporous micro-nano robot for targeted cargo delivery, characterized in that: It includes the preparation of the sol-gel magnetic core and the preparation of the chemically synthesized mesoporous shell.

8. The preparation process of a core-shell mesoporous micro-nanorobot for targeted cargo delivery according to claim 7, characterized in that: In the preparation process of the sol-gel magnetic core, iron chloride reacts with sodium hydroxide to form iron hydroxide colloid. The iron hydroxide colloid seeds are heated in an environment containing sodium sulfate to transform into iron oxide and gradually grow, starting from the initial seed state and gradually growing into a spindle shape, and finally growing into an ellipsoidal iron oxide magnetic core; In the preparation process of the chemically synthesized mesoporous shell, due to the hydrophilicity of the surface of the iron oxide magnetic core and due to electrostatic interaction, dopamine nanoparticle seeds gradually aggregate and grow on its surface in an alkaline environment; In addition, due to the poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymer, namely P123, which affects the aggregation degree of dopamine on the surface of the magnetic core, a poly(dopamine) shell with a mesoporous structure will be generated on the surface of the iron oxide core; Finally, a core-shell type mesoporous micro-nanorobot wrapped with poly(dopamine) is obtained.

9. The preparation process of a core-shell mesoporous micro-nanorobot for targeted cargo delivery according to claim 8, characterized in that: The porosity of the mesoporous shell of the core-shell mesoporous micro-nanorobot is adjusted by changing the dosages of ammonia water and P123 in the preparation of the chemically synthesized mesoporous shell.

10. The preparation process of a core-shell mesoporous micro-nanorobot for targeted cargo delivery according to claim 9, characterized in that: In the synthesis process of the poly(dopamine) mesoporous shell, the aggregation degree of P123 on dopamine is affected by the acidity and alkalinity in the environment. The increase in the ammonia water concentration leads to an increase in the alkalinity in the solution, resulting in a denser mesoporous structure; in addition, as the concentration of P123 in the solution decreases, dopamine will tightly aggregate and grow on the surface of the core to form nano-scale radial mesopores.

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