A novel polydopamine nanomotor and a preparation method and application thereof
By forming dopamine nanobottle structures on polystyrene microspheres and combining them with a dual-enzyme cascade reaction, the problems of restricted movement and low drug delivery efficiency of existing nanomotors in physiological environments were solved, achieving stable movement and efficient drug delivery of biocompatible nanomotors in biofluids.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HANGZHOU NORMAL UNIVERSITY
- Filing Date
- 2026-03-26
- Publication Date
- 2026-07-14
AI Technical Summary
Existing polydopamine nanomotors have many shortcomings in terms of driving performance, preparation process, and biomedical adaptability, making it difficult to achieve stable movement and efficient drug delivery in physiological environments with high ion concentrations.
Using polystyrene microspheres as templates, a core-shell structure was formed through dopamine self-polymerization. Combined with a cascade reaction of glucose oxidase and catalase, a polydopamine nanobottle with a single opening was prepared. Oxygen bubbles were used to drive the movement of the nanomotor and achieve drug loading.
It achieves stable motion and targeted delivery in biofluids, improves drug delivery efficiency and biocompatibility, simplifies the preparation process, and enhances driving performance and drug delivery synergy.
Smart Images
Figure CN122376777A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of nanomotor technology, and more specifically, to a novel polydopamine nanomotor, its preparation method, and its application. Background Technology
[0002] Micro- and nanomotors, as miniature intelligent devices capable of converting energy into autonomous kinetic energy, have shown great application potential in fields such as drug delivery, environmental remediation, and precision medicine. Particularly in drug delivery, their autonomous movement capabilities can significantly improve the enrichment efficiency of drugs in lesion areas, overcoming the mass transfer limitations of traditional passive delivery systems. With the increasingly stringent requirements for biocompatibility in the biomedical field, the development of low-toxicity, biocompatible, and controllable motion performance nanomotors has become a research hotspot.
[0003] Polydopamine (PDA) has become an ideal material for constructing biomedical nanomotors due to its excellent biocompatibility, surface adhesion properties, and pH response characteristics. Its abundant phenolic hydroxyl and amino groups on its surface enable efficient loading of functional components such as enzymes and drug molecules, giving it unique advantages in intelligent drug delivery systems. Currently reported PDA nanomotors mostly employ single-enzyme-driven or external stimulus-driven modes such as light and magnetism; however, these existing technologies still face many bottlenecks in practical applications.
[0004] In terms of driving performance, existing chemically driven polydopamine nanomotors often rely on single-enzyme catalytic reactions for power, such as urease catalyzing the decomposition of urea and catalase catalyzing the decomposition of hydrogen peroxide. These methods suffer from low motion efficiency and short duration of power, and some driving substrates (such as high-concentration hydrogen peroxide) are biotoxic, making them difficult to adapt to the in vivo physiological environment. While externally stimulated motors driven by light or magnetism offer greater controllability, they require external equipment, limiting their application in deep tissues or closed physiological environments. Furthermore, some photothermal driving materials (such as gold nanoparticles) exhibit poor stability and insufficient biocompatibility. Simultaneously, traditional nanomotors are prone to motion obstruction in high-ion-concentration physiological environments, further restricting their in vivo applications.
[0005] In terms of preparation and functional integration, existing polydopamine nanomotors often employ complex processes such as template electrodeposition and layer-by-layer self-assembly, which suffer from cumbersome steps, poor morphology controllability, and difficulty in mass production. Furthermore, most motors struggle to achieve efficient synergy between driving and drug delivery functions, exhibiting either low enzyme loading efficiency and easy inactivation, or poor drug loading and release performance, significantly diminishing their practical application effectiveness. Some multi-enzyme synergistic driving systems also suffer from inaccurate enzyme localization and poor synergistic catalytic efficiency, failing to fully leverage the advantages of multi-enzyme cascade reactions.
[0006] In terms of biomedical adaptability, existing nanomotors lack precision in particle size distribution and surface charge regulation. Some nanomotors are easily cleared by immune cells in vivo due to improper surface charge, or are too large to penetrate the tissue barrier of lesions. At the same time, most polydopamine nanomotors lack efficient driving mechanisms based on endogenous substrates in vivo, making it difficult to achieve continuous and stable autonomous movement in the physiological microenvironment, thus affecting the accuracy and efficiency of drug delivery.
[0007] To address the problems existing in the above-mentioned technologies, developing a polydopamine nanomotor that is simple to prepare, driven by endogenous substrates, has stable motion performance, excellent biocompatibility, and can achieve efficient synergy between driving and drug delivery functions is the key to promoting the large-scale application of nanomotors in the biomedical field, and is also a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention
[0008] In view of this, the present invention proposes a novel polydopamine nanomotor, its preparation method and application, aiming to solve the problems of low motion efficiency and short power duration of existing chemically driven polydopamine nanomotors, as well as the problem of motion being hindered in physiological environments with high ion concentrations.
[0009] This invention proposes a novel method for preparing polydopamine nanomotors, comprising the following steps: Polystyrene microspheres, dopamine, and an alkaline solvent were mixed and polymerized under anaerobic conditions to obtain polydopamine-coated polystyrene microspheres. Polydopamine-coated polystyrene microspheres were mixed with a swelling agent and swelled to obtain a mixed solution containing polydopamine nanobottles; Polydopamine nanomotors were obtained by mixing and reacting polydopamine nanobottles, alkaline solvents, glucose oxidase, and catalase.
[0010] Preferably, the polystyrene microspheres have a particle size of 200~1000 nm; The mass ratio of dopamine to polystyrene microspheres is 800~1000:1.
[0011] Preferably, the alkaline solvent is a phosphate buffer and / or a tris(hydroxymethyl)aminomethane hydrochloride buffer. The pH of the alkaline solvent is 7.2 to 7.5.
[0012] Preferably, the polymerization reaction is carried out at a temperature of 4-10°C for 8-24 hours.
[0013] Preferably, the swelling agent comprises one or more of toluene, tetrahydrofuran, and sodium dodecyl sulfonate; The swelling time is 5-10 hours.
[0014] Preferably, the ratio of glucose oxidase, catalase and dopamine is 1~2:1~2:10.
[0015] The present invention provides a polydopamine nanomotor prepared by the above preparation method, wherein the polydopamine nanomotor has a particle size of 500 nm to 1 μm and a negative charge on its surface.
[0016] The present invention also provides an application of the above-mentioned polydopamine nanomotor in drug delivery, comprising the following steps: The drug is loaded into the cavity of the polydopamine nanomotor.
[0017] Preferably, the drug includes small molecule drugs, macromolecule drugs, and biomolecules.
[0018] Preferably, the polydopamine nanomotor is driven by gas generated through a dual-enzyme cascade in a glucose-containing system; The glucose concentration in the glucose-containing system is 3-50 mmol / L.
[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention uses polystyrene microspheres as a template. After forming a core-shell structure through dopamine self-polymerization, the template swelling is precisely controlled to induce asymmetric rupture of the polydopamine shell, resulting in a polydopamine nanobottle with a single opening. Utilizing the abundant amino groups on the polydopamine surface, glucose oxidase and catalase are covalently immobilized thereon. The motor's movement depends on a cascade reaction of glucose oxidase and catalase: glucose oxidase catalyzes glucose to produce hydrogen peroxide, which is then decomposed by catalase to generate oxygen bubbles. Oxygen is asymmetrically ejected from the nanobottle opening, generating thrust to drive the motor. This invention provides a promising platform for applications such as targeted delivery in biofluids (e.g., blood). Attached Figure Description
[0020] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a SEM image of the polydopamine-coated polystyrene microspheres prepared in Example 1 of this invention; Figure 2 This is a SEM image of the polydopamine nanobottle prepared in Example 1 of the present invention; Figure 3 This is a SEM image of the polydopamine nanomotor prepared in Example 1 of the present invention; Figure 4 The results show the motion trajectory, mean square displacement (MSD), and average velocity of the polydopamine nanomotor prepared in Example 1 of this invention. Figure 5 The results of glucose oxidase activity testing in the poly-nano motor prepared in Example 1 of this invention; Figure 6 The results of the cytotoxicity test of the poly-nano motor prepared in Example 1 of this invention; Figure 7 This is the drug release curve of the poly-nano motor prepared in Example 1 of the present invention. Detailed Implementation
[0021] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention. It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the present invention.
[0022] Furthermore, regarding the numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included within this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.
[0023] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.
[0024] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.
[0025] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.
[0026] This invention proposes a novel method for preparing polydopamine nanomotors, comprising the following steps: Polystyrene microspheres, dopamine, and an alkaline solvent were mixed and polymerized under anaerobic conditions to obtain polydopamine-coated polystyrene microspheres. Polydopamine-coated polystyrene microspheres were mixed with a swelling agent and swelled to obtain a mixed solution containing polydopamine nanobottles; Polydopamine nanomotors were obtained by mixing and reacting polydopamine nanobottles, alkaline solvents, glucose oxidase, and catalase.
[0027] In this invention, the polystyrene microspheres have a particle size of 200~1000 nm.
[0028] In this invention, the mass ratio of dopamine to polystyrene microspheres is 800~1000:1, preferably 830~980:1, more preferably 850~950:1, and even more preferably 880~920:1.
[0029] In this invention, the mixing ratio of dopamine to alkaline solvent is 1:10~50, preferably 1:10~30, more preferably 1:10~20, and even more preferably 1:10.
[0030] In this invention, the alkaline solvent is a phosphate buffer and / or a tris(hydroxymethyl)aminomethane hydrochloride buffer.
[0031] In this invention, the pH of the alkaline solvent is 7.2 to 7.5.
[0032] In this invention, the temperature of the polymerization reaction is 4~10℃, preferably 5~9℃, more preferably 6~8℃, and even more preferably 7℃; the time is 8~24h, preferably 10~22h, more preferably 12~20℃, and even more preferably 14~18h.
[0033] In this invention, the swelling agent includes one or more of toluene, tetrahydrofuran, and sodium dodecyl sulfonate.
[0034] In this invention, the swelling time is 5-10 hours, preferably 6-9 hours, and more preferably 7-8 hours.
[0035] In this invention, the ratio of glucose oxidase, catalase and dopamine is 1~2:1~2:10, preferably 1.2~1.8:1.2~1.8:10, more preferably 1.4~1.6:1.4~1.6:10, and even more preferably 1.5:1.5:10.
[0036] The present invention provides a polydopamine nanomotor prepared by the above preparation method, wherein the polydopamine nanomotor has a particle size of 500 nm to 1 μm and a negative charge on its surface.
[0037] The present invention also provides an application of the above-mentioned polydopamine nanomotor in drug delivery, comprising the following steps: Drugs are loaded into the cavity of a polydopamine nanomotor, including small molecule drugs, macromolecule drugs, and biomolecules.
[0038] In this invention, the polydopamine nanomotor generates gas through a dual-enzyme cascade in a glucose-containing system to drive the nanomotor. In this invention, the concentration of glucose in the glucose-containing system is 3~50 mmol / L.
[0039] Example 1 At room temperature (25℃), 0.5 mL of a 0.5% w / v polystyrene microsphere solution (500 nm particle size) and 2.5 mg of dopamine were sequentially added to a round-bottom flask containing 10 mL of tris(hydroxymethyl)aminomethane hydrochloride buffer (pH 8.0). Polymerization was carried out under a nitrogen atmosphere at 4℃ for 4 hours with stirring to obtain a polydopamine-coated polystyrene microsphere solution. The mixture was then centrifuged at 6000 rpm, and the precipitate was washed with water. This process was repeated three times to obtain polydopamine-coated polystyrene microspheres, which were characterized using scanning electron microscopy. The results are shown below. Figure 1 As shown, it presents a uniform spherical shape.
[0040] Dopamine-coated polystyrene microspheres and 10 mL of swelling agent (a 1% v / v toluene-water suspension containing 0.01% w / v sodium dodecyl sulfonate) were added to a round-bottom flask and stirred at 300 rpm for 6 hours to induce swelling. The swelling of the polystyrene microspheres was then terminated by adding 20 mL of ethanol. The mixture was then centrifuged at 6000 rpm, and the precipitate was washed with water. This process was repeated three times. The swollen dopamine-coated polystyrene microspheres were redispersed in 10 mL of tetrahydrofuran and stirred for 4 hours to remove the polystyrene microsphere template. The mixture was then centrifuged again at 6000 rpm, and the precipitate was washed with water to obtain polydopamine nanobottles. These nanobottles were characterized using scanning electron microscopy, and the results are shown below. Figure 2 As shown, it is a hollow microsphere.
[0041] 10 mg of polydopamine nanoparticles were added to a round-bottom flask containing 10 mL of tris(hydroxymethyl)aminomethane hydrochloride buffer (pH 7.4), followed by the addition of 1.0 mg of glucose oxidase and 1.0 mg of catalase. The reaction was carried out at 4°C for 12 hours. After the reaction was complete, the mixture was centrifuged at 6000 rpm and washed with water to obtain polydopamine nanomotors. These nanomotors were characterized using scanning electron microscopy, and the results are shown below. Figure 3 As shown, the structure has not changed compared to the polydopamine nanobottle.
[0042] Example 2 At room temperature, 0.5 mL of polystyrene microsphere solution (500 nm, 0.5% w / v) and 2.5 mg of dopamine were sequentially added to a round-bottom flask containing 10 mL of phosphate buffer (pH 8.0). Polymerization was carried out under a nitrogen atmosphere at 6°C for 4 hours with stirring. The mixture was then centrifuged at 6000 rpm, and the precipitate was washed with water. This process was repeated three times to obtain polydopamine-coated polystyrene microspheres.
[0043] Dopamine-coated polystyrene microspheres and 10 mL of tetrahydrofuran were added to a round-bottom flask and stirred at 300 rpm for 6 hours until the polystyrene microspheres were completely dissolved. Then, 20 mL of ethanol was added to stop the swelling of the polystyrene microspheres, followed by centrifugation at 6000 rpm. The precipitate was washed with water, and this process was repeated three times. The swollen dopamine-coated polystyrene microspheres were redispersed in 10 mL of tetrahydrofuran and stirred for 4 hours to remove the polystyrene microsphere template. The mixture was then centrifuged again at 6000 rpm, and the precipitate was washed with water to obtain polydopamine nanobottles.
[0044] 10 mg of polydopamine nanoparticles were added to a round-bottom flask containing 10 mL of phosphate buffer (pH 7.4), and 1.0 mg of glucose oxidase and 1.0 mg of catalase were added, respectively. The reaction was carried out at 4 °C for 12 hours. After the reaction was completed, the mixture was centrifuged at 6000 rpm and washed with water to obtain polydopamine nanomotors.
[0045] Example 3 At room temperature, 0.5 mL of polystyrene microsphere solution (500 nm, 0.5% w / v) and 10 mg of dopamine were sequentially added to a round-bottom flask containing 10 mL of phosphate buffer (pH 8.0). Polymerization was carried out under a nitrogen atmosphere at 6°C for 4 hours with stirring. The mixture was then centrifuged at 6000 rpm, and the precipitate was washed with water. This process was repeated three times to obtain polydopamine-coated polystyrene microspheres.
[0046] Dopamine-coated polystyrene microspheres and 10 mL of a swelling agent containing tetrahydrofuran were added to a round-bottom flask and stirred at 300 rpm for 6 hours to induce swelling. Then, 20 mL of ethanol was added to stop the swelling of the polystyrene microspheres. The mixture was then centrifuged at 6000 rpm, and the precipitate was washed with water. This process was repeated three times. The swollen dopamine-coated polystyrene microspheres were redispersed in 10 mL of tetrahydrofuran and stirred for 4 hours to remove the polystyrene microsphere template. The mixture was then centrifuged again at 6000 rpm, and the precipitate was washed with water to obtain polydopamine nanobottles.
[0047] 10 mg of polydopamine nanoparticles were added to a round-bottom flask containing 10 mL of phosphate buffer (pH 7.4), and 1.0 mg of glucose oxidase and 1.0 mg of catalase were added, respectively. The reaction was carried out at 4 °C for 12 hours. After the reaction was completed, the mixture was centrifuged at 6000 rpm and washed with water to obtain polydopamine nanomotors.
[0048] Example 4 At room temperature, 0.5 mL of polystyrene microsphere solution (500 nm, 0.5% w / v) and 10 mg of dopamine were sequentially added to a round-bottom flask containing 10 mL of phosphate buffer (pH 8.0). Polymerization was carried out under a nitrogen atmosphere at 6°C for 4 hours with stirring. The mixture was then centrifuged at 6000 rpm, and the precipitate was washed with water. This process was repeated three times to obtain polydopamine-coated polystyrene microspheres.
[0049] Dopamine-coated polystyrene microspheres and 10 mL of a swelling agent containing tetrahydrofuran were added to a round-bottom flask and stirred at 300 rpm for 6 hours to induce swelling. Then, 20 mL of ethanol was added to stop the swelling of the polystyrene microspheres. The mixture was then centrifuged at 6000 rpm, and the precipitate was washed with water. This process was repeated three times. The swollen dopamine-coated polystyrene microspheres were redispersed in 10 mL of tetrahydrofuran and stirred for 4 hours to remove the polystyrene microsphere template. The mixture was then centrifuged again at 6000 rpm, and the precipitate was washed with water to obtain polydopamine nanobottles.
[0050] 10 mg of polydopamine nanoparticles were added to a round-bottom flask containing 10 mL of phosphate buffer (pH 7.4), and 1.0 mg of glucose oxidase and 1.0 mg of catalase were added, respectively. The reaction was carried out at 4 °C for 12 hours. After the reaction was completed, the mixture was centrifuged at 6000 rpm and washed with water to obtain polydopamine nanomotors.
[0051] The performance of the polydopamine nanomotor prepared in Example 1 was tested: 1. Ten mg of polydopamine nanomotors were uniformly dispersed in PBS buffer solution and glucose solutions of different concentrations (3.9 mmol / L, 7.8 mmol / L, 15.6 mmol / L, 31.2 mmol / L), respectively. The motion trajectory was recorded using a laser confocal microscope. The mean square displacement (MSD) and average velocity were calculated as follows: Figure 4 As shown.
[0052] 2. The activity of glucose oxidase was detected using the Beyotime colorimetric assay kit. 40 μL of 10 μg / mL polydopamine nanomotor was added to a 96-well plate, followed by 160 μL of working solution. The plate was incubated at 37°C for 20 minutes, and then the UV absorbance at 510 nm was measured using a microplate reader. A standard curve was plotted using standard glucose oxidase samples at concentrations of 0, 20, 40, 60, 80, and 100 IU / mL. Figure 5 As shown, the enzyme activity of glucose oxidase in the nanomotor can be calculated to be 20 IU / mL based on the enzyme activity-absorbance standard curve.
[0053] 3. Polydopamine nanomotors were co-cultured with human epithelial cells at different concentrations for 24 h, and the viability of the human epithelial cells was then detected. Figure 6 As shown. Figure 6 The nanomotors shown have little effect on human epithelial cells in the concentration range of 1~100 μg / mL, exhibit good biocompatibility, and are harmless to the human body.
[0054] 4. 10 mg of polydopamine nanomotor and 1 mg of rhodamine were mixed in 10 mL of water and stirred for 5 hours. The mixture was then centrifuged at 6000 rpm, washed with water, and repeated three times. Rhodamine-loaded polydopamine nanomotors were obtained. These nanomotors were then placed in glucose solutions of different concentrations and stirred for 4 hours, while the UV absorbance of rhodamine in the supernatant was measured. The results were calculated as follows: Figure 7 The drug release curve shown is shown.
[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.
Claims
1. A method for preparing a novel polydopamine nanomotor, characterized in that, Includes the following steps: Polystyrene microspheres, dopamine, and an alkaline solvent were mixed and polymerized under anaerobic conditions to obtain polydopamine-coated polystyrene microspheres. Polydopamine-coated polystyrene microspheres were mixed with a swelling agent and swelled to obtain polydopamine-containing nanobottles; Polydopamine nanomotors were obtained by mixing and reacting polydopamine nanobottles, alkaline solvents, glucose oxidase, and catalase.
2. The method for preparing a novel polydopamine nanomotor according to claim 1, characterized in that, The polystyrene microspheres have a particle size of 200~1000 nm; The mass ratio of dopamine to polystyrene microspheres is 800~1000:
1.
3. The method for preparing a novel polydopamine nanomotor according to claim 1, characterized in that, The alkaline solvent is phosphate buffer and / or tris(hydroxymethyl)aminomethane hydrochloride buffer; The pH of the alkaline solvent is 7.2 to 7.
5.
4. The method for preparing a novel polydopamine nanomotor according to claim 1, characterized in that, The polymerization reaction is carried out at a temperature of 4~10℃ for 8~24h.
5. The method for preparing a novel polydopamine nanomotor according to claim 1, characterized in that, The swelling agent includes one or more of toluene, tetrahydrofuran, and sodium dodecyl sulfonate; The swelling time is 5-10 hours.
6. The method for preparing a novel polydopamine nanomotor according to claim 1, characterized in that, The ratio of glucose oxidase, catalase and dopamine is 1~2:1~2:
10.
7. The polydopamine nanomotor prepared by the preparation method according to any one of claims 1 to 6, characterized in that, The polydopamine nanomotor has a particle size of 500 nm to 1 μm and a negatively charged surface.
8. The application of the polydopamine nanomotor according to claim 7 in drug delivery, characterized in that, Includes the following steps: The drug is loaded into the cavity of the polydopamine nanomotor.
9. The application of the polydopamine nanomotor according to claim 9 in drug delivery, characterized in that, The drugs include small molecule drugs, large molecule drugs, and biomolecules.
10. The application of the polydopamine nanomotor according to claim 9 in drug delivery, characterized in that, The polydopamine nanomotor is driven by gas generated through a dual-enzyme cascade in a glucose-containing system. The glucose concentration in the glucose-containing system is 3-50 mmol / L.