Preparation method of multi-mode magnetic field control permanent magnetic aerogel and drug release application of multi-mode magnetic field control permanent magnetic aerogel

Abstract

The invention relates to the technical field of composite material preparation, in particular to a preparation method and drug release application of multi-mode magnetic field control permanent magnetic aerogel. Firstly, a vertical orientation magnetic field is applied, so that the permanent magnetic neodymium iron boron aerogel is stably kept in a vertical posture in gastric juice, the contact area between the drug release surface of the aerogel and the gastric juice is minimum, and the non-specific leakage and the initial burst release effect of the drug can be effectively inhibited; secondly, under the condition of no magnetic field, the aerogel is kept in a horizontal floating state in gastric juice, the drug release surface is in complete contact with the gastric juice, and the drug is freely and slowly released from aerogel pore channels, so that low-content release is realized; finally, by applying a dynamic horizontal rotating magnetic field, the aerogel in a lying state is driven to stably rotate, high-content release of the medicine is actively and efficiently triggered, the problems that a traditional oral preparation is poor in stomach targeting, uncontrollable in release, short in residence time and the like are solved, and an innovative solution is provided for intelligent and accurate medicine delivery.

Description

Technical Field

[0001] This invention relates to the field of composite material preparation technology, specifically to a method for preparing multimodal magnetic field-controlled permanent magnet aerogel and its drug release application. Background Technology

[0002] Oral drug delivery, as the most mainstream method of drug administration in clinical practice, is widely used in chronic disease management and infection treatment due to its core advantages of being non-invasive, low-cost, having broad drug compatibility, and high patient compliance. However, oral drug delivery systems still face two major technical bottlenecks in the gastric environment, which seriously restrict drug bioavailability and therapeutic efficacy: first, how to implement oral treatment of biologics while ensuring that bioavailability is no less than that of subcutaneous injection; second, how to achieve targeted therapy of certain drugs in the gastrointestinal tract.

[0003] To address these issues, existing technologies primarily aim to improve absorption efficiency by extending drug retention time in the stomach. Based on their mechanisms of action, these technologies can be categorized into three types: floating formulations, expanding formulations, and bioadhesive formulations. While these strategies can prolong drug residence time in the stomach to some extent, they all rely on passive retention mechanisms. They cannot actively respond to external signals to regulate the retention location and duration. Furthermore, the drug release process still depends on the physiological environment of the stomach, such as pH and enzymatic hydrolysis, making precise controlled release difficult. This limitation restricts treatment efficiency, especially for conditions requiring localized targeted drug delivery, such as gastric ulcers and Helicobacter pylori infection.

[0004] Magnetic fields, as a precisely tunable non-contact physical field, possess unique advantages such as safety, non-invasiveness, rapid response, and strong spatial maneuverability, and have shown broad application prospects in the biomedical field in recent years. For example, ferromagnetic microrobots can navigate along narrow blood vessels under magnetic field drive, magnetically controlled capsule endoscopy can achieve targeted sampling and drug delivery in the gastrointestinal tract, and magnetic nanoclusters can achieve active intravascular delivery through magnetic field control. Inspired by this, integrating magnetic response characteristics into oral formulations can construct an active intelligent drug delivery system. By using an external magnetic field to achieve precise spatial anchoring and attitude control of the formulation in the stomach, the uncertainty of passive retention can be fundamentally solved. Furthermore, by designing different magnetic field modes (such as magnetically controlled standing, magnetically controlled lying, and magnetically controlled rotation), on-demand "on / off" control of drug release can be achieved. This magnetically controlled strategy, which integrates "positioning and retention" with "controlled release," is expected to achieve active management of the spatiotemporal behavior of oral drugs in vivo, providing a new technological path for significantly improving bioavailability and achieving local targeted therapy. Summary of the Invention

[0005] The purpose of this invention is to address how to improve the retention capacity and bioavailability of drugs in the stomach. Magnetic control systems have attracted widespread attention due to their controllability, safety, and non-contact operation. By constructing a magnetically controllable oral drug delivery strategy, it is expected to achieve controlled retention and controllable release of drugs in the stomach. This invention provides a method for preparing multimodal magnetic field-controlled permanent magnet aerogels and their drug release applications.

[0006] To achieve the above objectives, this invention discloses a method for preparing multimodal magnetic field-controlled permanent magnetic neodymium iron boron aerogel, comprising the following steps: S1. Neodymium iron boron particles and dopamine hydrochloride are gently magnetically stirred in a Tris-hydrochloric acid buffer solution with pH=8.5 to form magnetic neodymium iron boron particles coated with polydopamine. S2. Mix the magnetic neodymium iron boron particles coated with polydopamine obtained in step S1 with the silk fibroin solution to obtain a mixed solution. S3. Pour the mixed solution obtained in step S2 into a mold, perform orientation freezing for 15-20 min, and then freeze-dry to obtain neodymium iron boron aerogel. S4. The neodymium iron boron aerogel obtained in step S3 is immersed in methanol solution for solvation treatment. S5. Freeze the aerogel obtained in step S4 in liquid nitrogen, and finally freeze-dry it to obtain the treated NdFeB aerogel. S6. The aerogel obtained in step S5 is magnetized to obtain a permanent magnetic neodymium iron boron aerogel with magnetic anisotropy.

[0007] The multimodal magnetic field-controlled permanent magnet aerogel of this invention possesses a high magnetic particle loading capacity and exhibits significant remanence and magnetic anisotropy after directional magnetization, providing a foundation for precise spatial manipulation under an external magnetic field. In the complex physiological environment simulating the human gastrointestinal tract, thanks to the physical barrier provided by the polydopamine coating and the stable crystalline structure of the β-sheet in silk fibroin, this aerogel can effectively resist gastric acid erosion, enzymatic degradation, and hydrodynamic impacts, maintaining the structural integrity and long-term stability of its three-dimensional porous framework, thereby avoiding magnetic particle leakage or drug release due to material damage. Furthermore, by controlling the intensity, direction, and frequency of the external magnetic field, precise manipulation of the aerogel's spatial positioning, posture control (e.g., vertical standing), and movement patterns (e.g., rotational release) within the gastric environment can be achieved. This permanent magnetic neodymium iron boron aerogel effectively solves key problems in the delivery of traditional oral formulations to the stomach, such as short residence time, weak targeting ability, and uncontrollable release behavior, providing a new material system with good clinical translational potential for improving drug bioavailability and local therapeutic effects.

[0008] This invention also claims protection for the application of the above-mentioned multimodal magnetic field-controlled permanent magnetic neodymium iron boron aerogel in drug delivery for the treatment of gastric diseases.

[0009] Compared with the prior art, the beneficial effects of the present invention are as follows: By synergistically optimizing the structure-activity relationship between "highly magnetic particle loading" and "oriented hierarchical porous structure," and combining a multi-mode magnetocontrol strategy of "magnetically controlled standing, static levitation, and magnetocontrolled rotation," a permanent magnetic aerogel with excellent magnetic responsiveness, structural stability, and controlled drug release was successfully constructed. This system enables active retention and programmed release of drugs in the gastric target area, significantly improving the local concentration and duration of action of orally administered drugs. It provides an innovative technical solution to address the problems of inaccurate localization, uncontrollable release, and large individual variability in traditional gastric drug delivery. Attached Figure Description

[0010] Figure 1 Transmission electron microscope (TEM) images and scanning electron microscope (SEM) images of neodymium iron boron (NdFeB) particles; Figure 2 Transmission electron microscope (TEM) and scanning electron microscope (SEM) images of neodymium iron boron@polydopamine particles; Figure 3 Particle size distribution diagrams of NdFeB particles and NdFeB@polydopamine particles; Figure 4 Zeta potential diagrams for NdFeB particles and NdFeB@polydopamine particles; Figure 5 Infrared absorption spectra of neodymium iron boron particles, polydopamine particles, and neodymium iron boron@polydopamine particles; Figure 6 Optical photographs of silk fibroin aerogel, permanent magnetic neodymium iron boron aerogel, and capsule No. 00; Figure 7 Optical images and SEM images of permanent magnetic NdFeB aerogel with macroscopic orientation channels; Figure 8 X-ray diffraction patterns of silk fibroin aerogel, permanent magnetic NdFeB aerogel, and NdFeB@polydopamine; Figure 9 Infrared absorption spectra of silk fibroin solution, silk fibroin aerogel, and permanent magnet aerogel, as well as their β-sheet content; Figure 10 Scanning images of the pore structure of permanent magnetic NdFeB aerogels with different NdFeB@polydopamine:silk fibroin ratios; Figure 11 Floating state diagram of permanent magnetic NdFeB aerogels with different NdFeB@polydopamine:silk fibroin ratios in water; Figure 12Optical photographs, remanence histograms, and hysteresis loops of permanent magnetic neodymium iron boron aerogels with a molecular weight ratio of neodymium iron boron@polydopamine:silk fibroin protein of 1:2 and 2:2 under a magnetometer. Figure 13 Optical photographs of the rotating magnetic field device, optical photographs of iron oxide aerogel under a magnetometer, optical photographs of NdFeB@polydopamine:silk fibroin protein permanent magnet NdFeB aerogels with a mass ratio of 1:2 and 2:2, and optical photographs of iron oxide aerogel taken at a distance of 5 cm from the rotating magnetic field. Figure 14 Optical photographs of permanent magnetic neodymium iron boron aerogel at different time points during 24 hours of placement in a simulated gastric fluid environment; Figure 15 Optical photographs of permanent magnetic neodymium iron boron aerogel at different time points during 24 hours of placement in a simulated intestinal fluid environment; Figure 16 The content of β-sheet in permanent magnetic neodymium iron boron aerogel after treatment in simulated gastric and intestinal fluid environments; Figure 17 Optical photographs at different time points showing the absorption of doxorubicin hydrochloride solution by permanent magnetic neodymium iron boron aerogel; Figure 18 Optical photographs and comparisons of drug release rates and drug release times at different times for drug-loaded capsules in simulated gastric juice under magnetically controlled rotation; Figure 19 This is a photograph of the drug-loaded permanent magnetic neodymium iron boron aerogel releasing the drug after 0.5 h in three different orientations. Figure 20 The bar chart shows the drug release rate of drug-loaded permanent magnetic neodymium iron boron aerogel after 0.5 h in three postures. Figure 21 This is a bar chart showing the drug release rate of drug-loaded permanent magnetic neodymium iron boron aerogel after 0.5 h under rotating magnetic fields of different frequencies. Detailed Implementation

[0011] The above-mentioned and other technical features and advantages of the present invention will be described in more detail below with reference to the accompanying drawings.

[0012] Example 1: Preparation method of NdFeB@polydopamine particles: NdFeB (1 g) and dopamine hydrochloride (0.25 g) were dissolved in Tris-hydrochloric acid buffer solution (pH=8.5), and the mixture was magnetically stirred at room temperature for 24 hours to generate polydopamine-coated NdFeB. The above mixture was centrifuged and washed three times with deionized water. The resulting solution was then subjected to a 4-hour period. o Save under C:\

[0013] Example 2: Preparation of permanent magnetic NdFeB aerogel with macroscopically oriented channels, the steps are as follows: S1: The concentration of the neodymium iron boron@polydopamine particle sample prepared in Example 1 was tested. After the test, the hydrophilic magnetic particles were mixed with the silk fibroin solution and ultrasonicated to make them uniformly mixed. In the resulting mixed solution, the concentration of the silk fibroin solution was 50 mg / mL and the concentration of the neodymium iron boron@polydopamine particles was 50 mg / mL. S2: The mixed solution is poured into a mold placed on a cold plate. The cold source is located at the bottom of the mold. Ice crystals grow vertically upwards in the mixed solution, perpendicular to the cold plate, creating an oriented channel structure. During the ice crystal growth process, as the mixed solution solidifies, the macroscopically oriented channel structure is fixed. Oriented freezing is then performed, and finally, freeze-drying yields a permanent magnet neodymium iron boron aerogel with macroscopically oriented channels.

[0014] Figure 1 These are transmission electron microscope (TEM) and scanning electron microscope (SEM) images of NdFeB particles. The images show that the NdFeB particles are irregularly shaped, vary in size, and have rough surfaces. Figure 2 The images show transmission electron microscopy (TEM) and scanning electron microscopy (SEM) images of NdFeB@polydopamine particles. The images reveal that polydopamine modification forms a complete coating film on the particle surface, but the modification process does not significantly alter the basic morphology of the NdFeB particles. Figure 3 The particle size distribution diagrams of NdFeB particles and NdFeB@polydopamine particles show that the polydopamine modification process did not have a significant effect on the particle size. Figure 4 The Zeta potential diagrams are for NdFeB particles and NdFeB@polydopamine particles. After modification with polydopamine, the Zeta potential of the magnetic particles changed from ~-10 mV to about ~-23 mV. This change confirms the successful coating of polydopamine. Figure 5 The infrared absorption spectra of NdFeB particles, polydopamine particles, and NdFeB@polydopamine particles are shown, located at 1280 and 1510 cm⁻¹. -1 The peaks at 3200 cm⁻¹ represent amides III and II of polydopamine, while those at 3200 cm⁻¹ represent amides III and II of polydopamine. -1 The broad peak at that location is a -OH group, confirming the successful modification of polydopamine; Figure 6 Optical photographs of silk fibroin aerogel, permanent magnetic neodymium iron boron aerogel, and capsule No. 00 are shown. As can be seen from the images, the silk fibroin aerogel is generally white. After adding neodymium iron boron@polydopamine particles, the aerogel changes from white to black. Moreover, its size is significantly smaller than that of the control capsule, indicating that the aerogel has good oral swallowability. Figure 7Optical images and scanning images of permanent magnetic neodymium iron boron aerogel with macroscopic oriented channels are shown. The optical images and scanning images show that the aerogel has a macroscopic oriented channel structure, which proves that the addition of magnetic particles does not affect the channel structure of the aerogel. Figure 8 X-ray diffraction patterns of silk fibroin aerogel, permanent magnetic NdFeB aerogel, and NdFeB@polydopamine are shown in the figure. It can be seen from the figure that the permanent magnetic NdFeB aerogel retains the broad diffraction pattern of silk fibroin aerogel in the β-fold region, and the characteristic diffraction peaks of NdFeB@polydopamine particles such as (105) and (006) are also clearly visible. This proves that the aerogel successfully introduced NdFeB@polydopamine particles and maintained their respective crystal structure characteristics. Figure 9 The figures show the infrared absorption spectra of silk fibroin solution, silk fibroin aerogel, and permanent magnetic NdFeB aerogel, as well as their β-sheet content. The figures indicate that while the permanent magnetic aerogel retains the characteristic absorption peaks of silk fibroin, it also affects the material's structure, successfully maintaining the basic conformation of silk fibroin and ensuring structural stability. The proportion of β-sheet structure significantly increases from silk fibroin solution to aerogel. After introducing magnetic components, the β-sheet proportion decreases slightly but remains much higher than in the original solution. The above data proves that the polydopamine coating has been successfully applied to the surface of NdFeB particles, and the modification process has not changed the original morphology and particle size distribution of the magnetic particles. At the same time, the prepared permanent magnet aerogel has successfully introduced NdFeB@polydopamine particles while maintaining the β-sheet conformation and macroscopic orientation porous structure of silk fibroin. Example 3: The floating test of permanent magnet aerogel in water, the steps are as follows: 1) Permanent magnetic NdFeB aerogels with different NdFeB@polydopamine:silk fibroin ratios were placed in cuvettes containing 3.5 mL of deionized water.

[0015] 2) After the aerogel has fully absorbed the deionized water, observe and record its floating state.

[0016] Figure 10 Scanning images of permanent magnet aerogels with different NdFeB@polydopamine:silk fibroin mass ratios show that when the mass ratio is higher than 2:2, the internal structure of the material tends to be dense, the pore size is significantly reduced, and the porosity is decreased. This structure will be unfavorable for the transport of substances necessary for the application process. Figure 11The graphs show the floating states of permanent magnetic NdFeB aerogels with different NdFeB@polydopamine:silk fibroin mass ratios in water. As can be seen from the graphs, when the mass ratio is higher than 2:2, the density of the prepared aerogel exceeds that of water, which prevents it from floating in water and thus limits its movement and operation capabilities in underwater environments.

[0017] Figure 12 Optical photographs, remanence histograms, and hysteresis loops of permanent magnetic NdFeB aerogels with NdFeB@polydopamine:silk fibroin mass ratios of 1:2 and 2:2, obtained using a magnetometer. The figures show that the magnetic intensity of the 2:2 sample is significantly higher than that of the 1:2 sample, thus requiring a lower external magnetic field strength for manipulation and exhibiting a more sensitive response. Figure 13 Optical photographs of the rotating magnetic field device, iron oxide aerogel under a magnetometer, and permanent magnetic NdFeB aerogels with mass ratios of 1:2 and 2:2 (neodymium iron boron@polydopamine:silk fibroin) and iron oxide aerogel taken at a distance of 5 cm from the rotating magnetic field. The results show that the permanent magnetic aerogel and iron oxide aerogel with a mass ratio of 1:2 failed to rotate effectively under these conditions, indicating that their magnetic responsiveness is weak and insufficient to drive themselves to follow the magnetic field at a set distance.

[0018] The above data collectively demonstrate that when the NdFeB@polydopamine:silk fibroin mass ratio is 2:2, the material can optimally balance the relationship between high magnetic load and porous structure, thus possessing both good motion controllability and structural permeability. Therefore, precise control of magnetic content is crucial for optimizing material performance; The above data indicate that, in order to evaluate the applicability of the permanent magnetic NdFeB aerogel prepared by the co-assembly method in oral drug delivery scenarios, further investigation is needed into its stability in the gastrointestinal environment. Therefore, the aerogel will be placed in simulated gastric and intestinal fluids to study the long-term stability of its material structure and properties.

[0019] Figure 14 The images show optical photographs of permanent magnetic NdFeB aerogel at different time points during 24 hours in a simulated gastric fluid environment. The images show that the solution color of the aerogel does not change within 24 hours, indicating that the permanent magnetic NdFeB aerogel has not been corroded or degraded. Figure 15 Optical photographs of permanent magnetic neodymium iron boron aerogel at various time points during 24 hours in a simulated intestinal fluid environment. The images show that the phenomenon is consistent with that in a simulated gastric fluid environment, indicating that it can maintain its structural stability in a simulated intestinal fluid environment.

[0020] Figure 16The figure shows the β-sheet content of permanent magnetic NdFeB aerogel after treatment in simulated gastric and intestinal fluid environments. As can be seen from the figure, the β-sheet content of the permanent magnetic aerogel increases after treatment, and its structure becomes more stable.

[0021] The above data demonstrates that permanent magnetic neodymium iron boron aerogel has excellent structural stability and can withstand harsh gastrointestinal conditions while maintaining structural stability, thus potentially improving its delivery performance in the gastrointestinal environment.

[0022] Example 6: Preparation of drug-loaded permanent magnetic NdFeB aerogel, the steps are as follows: Take 0.2 mL of a 5 mg / mL doxorubicin hydrochloride solution and drop it onto the aerogel. Once the aerogel is fully saturated with adsorption, the drug-loaded permanent magnet aerogel can be obtained.

[0023] The preparation steps of the drug-loaded capsule in Comparative Example 1 are as follows: The difference between this comparative example and Example 6 is that an equal amount and concentration of doxorubicin hydrochloride solution are directly injected into a gastric-soluble capsule to obtain a drug-loaded capsule.

[0024] Example 7: In vitro drug release performance of permanent magnetic neodymium iron boron aerogel, the steps are as follows: 1) Place the glass bottles in a suitable environment and keep them still for 0.5 hours without any additional stirring. For the aerogel in the stirring group, stir at the set frequency, and keep the other steps the same as for the still group.

[0025] 2) After the time interval, take appropriate amounts of sample solution from the glass bottles of the settling group and the stirring group respectively, and measure their absorbance using ultraviolet spectrophotometry. Based on the absorbance data, calculate the cumulative drug release amount using the corresponding calculation formula.

[0026] Figure 17 Optical photographs of permanent magnetic neodymium iron boron aerogel absorbing doxorubicin hydrochloride solution at different time points show that its surface is completely wetted within 140 seconds, indicating that the material has good drug loading capacity. Figure 18 To simulate drug release from gastric fluid-loaded capsules at different time points, optical photographs were taken, and the drug release rate and release time of drug-loaded permanent magnetic NdFeB aerogel under magnetically controlled rotation were compared. The results showed that traditional drug-loaded capsules experienced capsule rupture at approximately 40 minutes, triggering a burst drug release; while the drug-loaded permanent magnetic aerogel driven by magnetically controlled rotation achieved a sustained, controlled release for approximately 27 hours. This demonstrates the significant advantage of drug-loaded permanent magnetic NdFeB aerogel in prolonging drug action time. Figure 19The images show the actual drug released by the drug-loaded permanent magnetic neodymium iron boron aerogel in three postures over 0.5 h. As can be seen from the images, the color concentration of the released liquid varies significantly with the posture, indicating that the drug release behavior is posture-dependent and the release rate can be controlled by adjusting the posture. Figure 20 The bar chart shows the drug release rate of drug-loaded permanent magnetic neodymium iron boron aerogel in three orientations after 0.5 h. As can be seen from the figure, the drug release rate in the lateral orientation is about twice that in the vertical orientation, indicating that changing the aerogel's orientation can effectively delay drug release. In the rotating state, drug release is significantly accelerated, suggesting that this orientation is suitable for treatment scenarios that require rapid drug release. Figure 21 This is a bar chart showing the drug release rate of drug-loaded permanent magnetic NdFeB aerogel after 0.5 h under rotating magnetic fields of different frequencies. The chart shows a positive correlation between the drug release rate and the frequency of the applied magnetic field; the higher the frequency, the faster the release rate. This finding provides a direct regulatory basis for achieving on-demand, intelligent controlled drug release.

[0027] The above data demonstrate that the drug release behavior of permanent magnetic NdFeB aerogel exhibits significant attitude responsiveness, and the release kinetics can be flexibly controlled by simply changing its spatial orientation, providing a feasible physical strategy for targeted delivery and controlled release.

[0028] The above description is merely a preferred embodiment of the present invention and is illustrative rather than restrictive. Those skilled in the art will understand that many changes, modifications, and even equivalents can be made within the spirit and scope defined by the claims of the present invention, all of which will fall within the protection scope of the present invention.

Claims

1. A method for preparing multimodal magnetic field-controlled permanent magnetic neodymium iron boron aerogel, characterized in that, Includes the following steps: S1. Neodymium iron boron particles and dopamine hydrochloride are gently magnetically stirred in a Tris-hydrochloric acid buffer solution with pH=8.5 to form magnetic neodymium iron boron particles coated with polydopamine. S2. Mix the magnetic neodymium iron boron particles coated with polydopamine obtained in step S1 with the silk fibroin solution to obtain a mixed solution. S3. Pour the mixed solution obtained in step S2 into a mold, perform orientation freezing for 15-20 min, and then freeze-dry to obtain neodymium iron boron aerogel. S4. The neodymium iron boron aerogel obtained in step S3 is immersed in methanol solution for solvation treatment. S5. Freeze the aerogel obtained in step S4 in liquid nitrogen, and finally freeze-dry it to obtain the treated NdFeB aerogel. S6. The aerogel obtained in step S5 is magnetized to obtain a permanent magnetic neodymium iron boron aerogel with magnetic anisotropy.

2. The method for preparing a multimodal magnetic field-controlled permanent magnetic neodymium iron boron aerogel as described in claim 1, characterized in that, In step S1, the polydopamine coating is prepared using a solution oxidation method, specifically including: Neodymium iron boron (NdFeB) particles were dispersed in a Tris-hydrochloric acid buffer solution at pH 8.5, and dopamine hydrochloride was added. The mixture was mechanically stirred at room temperature to allow for complete reaction, yielding polydopamine-coated NdFeB particles. After the reaction was complete, the product was collected by centrifugation and washed three times with deionized water. o Store under C conditions.

3. The method for preparing a multimodal magnetic field-controlled permanent magnetic neodymium iron boron aerogel as described in claim 1, characterized in that, In step S2, the concentration of magnetic neodymium iron boron particles in the mixed solution is 50 mg / mL, and the concentration of silk fibroin solution is 50 mg / mL.

4. The method for preparing a multimodal magnetic field-controlled permanent magnetic neodymium iron boron aerogel as described in claim 1, characterized in that, In step S3, the cold source for the orientation freezing process is provided by liquid nitrogen, and the freeze-drying is carried out in a freeze dryer.

5. The method for preparing a multimodal magnetic field-controlled permanent magnetic neodymium iron boron aerogel as described in claim 1, characterized in that, In step S6, the magnetization process is carried out using a magnetizer, and the specific voltage parameters can be adjusted according to the required magnetic properties.

6. The method for preparing a multimodal magnetic field-controlled permanent magnetic neodymium iron boron aerogel as described in claim 5, characterized in that, The aerogel has an oriented, interconnected pore structure, with magnetic neodymium iron boron particles uniformly dispersed within the aerogel framework formed by silk fibroin.

7. The application of a multimodal magnetic field-controlled permanent magnetic neodymium iron boron aerogel as described in any one of claims 1-6 in oral drug delivery.

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