Magnetic fiber composite hydrogel material with orientation arrangement regulated and controlled by magnetic field and preparation method of magnetic fiber composite hydrogel material
By preparing Mn2O3-modified magnetic PLLA nanofibers and combining them with SilMA, and using magnetic field orientation and ultraviolet light crosslinking technology, a magnetic fiber composite hydrogel material with an ordered structure was constructed. This solved the problem of limited mechanical properties and single function of hydrogel materials, and achieved efficient mechanical enhancement and multifunctional integration.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-23
- Publication Date
- 2026-04-03
AI Technical Summary
Existing hydrogel materials are insufficient in terms of mechanical properties and single function, making it difficult to meet the needs of high-end application scenarios such as the repair of load-bearing tissues and directional signal transduction. Furthermore, magnetic particles are difficult to disperse and arrange uniformly in the hydrogel matrix.
By preparing Mn2O3-modified magnetic PLLA nanofibers and combining them with methacryloyl fibroin SilMA, and then combining them with a bacterial cellulose BC membrane substrate, a magnetic fiber composite hydrogel material with an ordered structure was constructed using magnetic field orientation and ultraviolet light crosslinking technology.
It significantly enhances the mechanical properties of hydrogels, achieves anisotropic structures, possesses catalytic, electrochemical, and pH-responsive functions, and expands the application potential of magnetothermal therapy and magnetic resonance imaging.
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Figure CN121779741A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of functional composite hydrogel materials technology, and in particular to a magnetic fiber composite hydrogel material with magnetic field-controlled orientation and its preparation method. Background Technology
[0002] Hydrogel materials, commonly found in existing technologies, have attracted widespread attention in the biomedical field due to their three-dimensional hydrophilic network structure, excellent biocompatibility, and biomimetic properties to biological microenvironments. However, traditional hydrogels generally suffer from poor mechanical properties and limited functionality, making it difficult to meet the dual requirements of mechanical properties and structural functions for high-end applications such as load-bearing tissue repair and directional signal transduction. While novel photocrosslinked hydrogels, represented by methacryloylsilane (SilMA), possess good biocompatibility and modifiability, their inherent limited mechanical strength and insufficient structural controllability restrict further applications.
[0003] Electrospun nanofibers, with their high specific surface area and extracellular matrix-like structure, are often used as reinforcing phases to improve the mechanical properties of hydrogels. For example, polylactic acid (PLLA), a biodegradable polymer, exhibits excellent mechanical properties in its electrospun fibers, and its degradation products demonstrate high biocompatibility. Introducing Fe3O4 nanoparticles can impart magnetic response properties to materials, providing possibilities for external regulation; however, magnetic particles are prone to aggregation, making it difficult to achieve uniform dispersion and orderly arrangement within the hydrogel matrix. Mn2O3, as an inorganic functional material with catalytic and electrochemical activity, can improve fiber dispersion through interfacial interactions by modifying the surface of magnetic nanofibers, while simultaneously endowing the fibers with additional functions, further expanding the application scenarios of composite hydrogels. Bacterial cellulose (BC) membranes possess a three-dimensional nanonetwork and high mechanical stability, serving as a substrate material that helps enhance the interfacial bonding and overall integrity of composite structures.
[0004] Although existing technologies include fiber-reinforced hydrogels, there are currently no publicly reported methods for constructing oriented composite hydrogels using Mn2O3-modified magnetic PLLA short fibers combined with magnetic field-induced orientation technology and a BC membrane substrate. Current methods still have significant limitations in achieving ordered fiber arrangement, enhanced mechanical properties, and integrated multifunctional characteristics, necessitating innovation in material structure design, functional composites, and fabrication processes.
[0005] Therefore, in view of the shortcomings of the existing technology, it is necessary to provide a magnetic fiber composite hydrogel material with magnetic field-controlled orientation and its preparation method to solve the shortcomings of the existing technology. Summary of the Invention
[0006] The first objective of this invention is to overcome the shortcomings of existing technologies by providing a method for preparing magnetic fiber composite hydrogel materials. The magnetic fiber composite hydrogel materials prepared by this method exhibit significantly enhanced mechanical properties and anisotropy, possess multiple composite functions, have a highly controllable structure, and can achieve highly oriented alignment.
[0007] The above-mentioned objectives of the present invention are achieved through the following technical measures:
[0008] A method for preparing a magnetic fiber composite hydrogel material is provided. Magnetic short nanofibers are prepared using polylactic acid (PLLA) and iron(III) oxide (Fe3O4) nanoparticles. The surface of the magnetic short nanofibers is then modified with potassium permanganate (KMnO4) to obtain Mn2O3-modified magnetic short nanofibers. Finally, the Mn2O3-modified magnetic short nanofibers are composited with methacryloyl fibroin (SilMA), and a bacterial cellulose (BC) membrane is used as a substrate. This is combined with magnetic field orientation and ultraviolet light crosslinking technology to construct a magnetic fiber composite hydrogel material with an ordered structure.
[0009] The method for preparing the magnetic fiber composite hydrogel material of the present invention includes the following steps:
[0010] S1. Magnetic nanofibers are obtained by electrospinning polylactic acid (PLLA) and iron(III) oxide (Fe3O4) nanoparticles.
[0011] S2. The magnetic nanofibers of S1 were pretreated with dopamine hydrochloride and then reacted with potassium permanganate KMnO4 to obtain Mn2O3 modified magnetic nanofibers.
[0012] S3, magnetic nanofibers modified with photoinitiator, methacrylamide silk fibroin SilMA and S2 Mn2O3 were obtained as a composite precursor solution.
[0013] S4. The composite precursor solution of S3 is cast into a bacterial cellulose BC membrane, and then the magnetic nanofibers are oriented in a magnetic field. Finally, photocrosslinking and curing are performed to obtain a magnetic fiber composite hydrogel material.
[0014] Preferably, S1 includes the following steps:
[0015] S1.1. Polylactic acid (PLLA) is added to hexafluoroisopropanol (HFIP) to obtain a PLLA solution with a mass concentration of 12% (w / v) to 18% (w / v);
[0016] S1.2 Add Fe3O4 nanoparticles to PLLA solution and ultrasonically disperse for 20 min to 40 min, with the mass concentration of Fe3O4 nanoparticles being 3% (w / v) to 6% (w / v) to obtain spinning solution;
[0017] S1.3. Electrospin the spinning solution of S1.2 using an electrospinning process and collect the fiber membrane.
[0018] S1.4. The fiber membrane from S1.3 is dried, then deionized water is added and the membrane is homogenized and pulverized in a high-speed homogenizer. The amount of deionized water added is 3500 to 4500 times the weight of polylactic acid (PLLA) to obtain the magnetic nanofibers.
[0019] Preferably, S2 above includes the following steps:
[0020] S2.1 Add Tris(hydroxymethylaminomethane) to double-distilled water to obtain a Tris(hydroxymethylaminomethane) solution with a Tris(hydroxymethylaminomethane) mass concentration of 0.5% (w / v) to 0.8% (w / v); then add hydrochloric acid to adjust the pH to 8.0 to 9.0, and proceed to S2.2;
[0021] S2.2 Add dopamine hydrochloride to the tris(hydroxymethyl)aminomethane solution in S2.1, with a mass concentration of 1.8 mg / mL to 2.2 mg / mL, then add the magnetic nanofibers from S1 with a mass concentration of 3% (w / v) to 6% (w / v), stir at room temperature in the dark for 10 to 12 hours, and then centrifuge to collect the precipitate.
[0022] S2.3. Add the precipitate of S2.2 to a potassium permanganate KMnO4 solution with a mass concentration of 0.10% (w / v) to 0.15% (w / v), and the mass concentration of the precipitate of S2.2 in the potassium permanganate solution is 1% (w / v) to 5% (w / v). Then stir at room temperature for 10 h to 12 h, and centrifuge to separate the solid to obtain Mn2O3 modified magnetic nanofibers.
[0023] Preferably, S3 above includes the following steps:
[0024] S3.1 Add photoinitiator to phosphate-buffered saline (PBS) solution, and then heat in a water bath at 40℃~50℃ in the dark for 10min~20min to obtain an initiator solution with a mass concentration of 0.20% (w / v)~0.30% (w / v);
[0025] S3.2 Add methacrylamide silk fibroin SilMA to the initiator solution in S3.1, stir or shake at room temperature in the dark for 0.5 h to 1 h to obtain a SilMA solution with a mass volume concentration of 8% (w / v) to 20% (w / v).
[0026] S3.3 Add the Mn2O3-modified magnetic nanofibers of S2 to the SilMA solution of S3.2 and then mix by shaking to obtain a composite precursor solution. The mass concentration of the Mn2O3-modified magnetic nanofibers in the SilMA solution is 5% (w / v) to 15% (w / v).
[0027] Preferably, S4 above includes the following steps:
[0028] S4.1. The composite precursor solution of S3 is cast onto the surface of the bacterial cellulose BC membrane, and the coating thickness of the composite precursor solution is 1mm to 3mm, to obtain the cast bacterial cellulose BC membrane.
[0029] S4.2 Place the cast bacterial cellulose BC membrane from S4.1 in a magnetic field with an intensity of 20mT to 50mT for 10min to 15min, and then irradiate it with ultraviolet light for 20s to 30s to perform photocrosslinking and curing, thereby obtaining a magnetic fiber composite hydrogel material.
[0030] In S1.3, the parameters of the electrospinning process are: voltage of 12kV to 18kV, receiving distance of 15cm to 20cm, spinning rate of 1.0mL / h to 1.5mL / h, ambient temperature of 25℃ to 30℃, and relative humidity of 40% to 50%.
[0031] Preferably, step S1.4 involves drying the fiber membrane from step S1.3 at 35°C to 40°C for 12 to 15 hours, then adding deionized water and placing it in a high-speed homogenizer. The homogenizer is then pulverized at 8000 rpm to 10000 rpm for 15 to 20 minutes, centrifuged, and the precipitate is collected to obtain the magnetic nanofibers.
[0032] Preferably, the above photoinitiator is lithium phenyl-2,4,6-trimethylbenzoyl phosphate (LAP).
[0033] In step S4.2, the wavelength of the ultraviolet light is 405 nm, and the power is 25 mW / cm². 2 .
[0034] The first objective of this invention is to overcome the shortcomings of the prior art by providing a magnetic fiber composite hydrogel material. This magnetic fiber composite hydrogel material can significantly enhance mechanical properties and is anisotropic, and it also has multiple composite functions, excellent controllability, and can achieve highly oriented alignment.
[0035] The above-mentioned objectives of the present invention are achieved through the following technical measures:
[0036] A magnetic fiber composite hydrogel material is provided, which is prepared by the above-mentioned method for preparing magnetic fiber composite hydrogel material.
[0037] This invention discloses a magnetic fiber composite hydrogel material with magnetically oriented alignment and its preparation method. The method involves preparing magnetic nanofibers using polylactic acid (PLLA) and iron(III) oxide (Fe3O4) nanoparticles. The surface of the magnetic nanofibers is then modified with potassium permanganate (KMnO4) to obtain Mn2O3-modified magnetic nanofibers. Finally, the Mn2O3-modified magnetic nanofibers are composited with methacryloyl fibroin (SilMA), and a bacterial cellulose (BC) membrane is used as a substrate. This is combined with magnetic field-oriented alignment and ultraviolet light crosslinking technology to construct a magnetic fiber composite hydrogel material with an ordered structure. The beneficial effects of this invention are: 1. Significantly enhanced and anisotropic mechanical properties. Because this invention utilizes oriented PLLA nanofibers to form a continuous reinforcing network, and uses a bacterial cellulose (BC) membrane as a substrate to enhance interfacial bonding, the tensile strength of the composite hydrogel parallel to the orientation direction is 2-3 times higher than that of pure SilMA hydrogel, and the mechanical properties differ significantly between the parallel and perpendicular orientation directions. 2. Multifunctional: This invention deposits Mn2O3 on the surface of magnetic nanofibers via a KMnO4 oxidation deposition reaction, endowing the material with catalytic, electrochemical, and pH-responsive drug release functions. Simultaneously, the magnetic responsiveness of Fe3O4 (Fe3O4) gives the material potential for magnetothermal therapy and magnetic resonance imaging. 3. Excellent structural controllability, achieving highly oriented alignment: In traditional fiber-reinforced hydrogels, fibers are often randomly distributed, making it difficult to form an ordered structure. This invention introduces Fe3O4 nanoparticles into PLLA nanofibers, endowing them with magnetic responsive properties. An external magnetic field is applied during the composite hydrogel molding stage, causing the magnetic nanofibers to align oriented along the magnetic field direction, achieving an orientation factor of over 80%, effectively mimicking the anisotropic microstructure of natural tissues. 4. Significantly improved mechanical properties with anisotropic characteristics: Addressing the issues of weak and isotropic mechanical properties in existing hydrogels, this invention utilizes oriented polylactic acid (PLLA) nanofibers as a reinforcing phase to construct a continuous reinforcing network within a methacryloyl fibroin (SilMA) matrix. Simultaneously, a bacterial cellulose (BC) membrane serves as the substrate to enhance interfacial bonding and stress transfer. This results in a 2-3 times increase in tensile strength along the orientation direction compared to pure SilMA hydrogels, meeting the directional mechanical property requirements for load-bearing tissue repair. 5. High functional integration and broad application potential: Existing hydrogels generally have limited functionality. This invention uses potassium permanganate oxidation deposition to uniformly modify the surface of magnetic fibers with a Mn2O3 layer, endowing the material with catalytic activity, electrochemical response characteristics, and pH-responsive drug release capabilities. Furthermore, the Fe3O4 component endows the hydrogel with magnetocaloric conversion and magnetic resonance imaging potential, expanding its application prospects in multifunctional biomedical fields such as tumor treatment, diagnosis, and intelligent drug delivery. Attached Figure Description
[0038] The invention will be further described with reference to the accompanying drawings, but the contents of the drawings do not constitute any limitation on the invention.
[0039] Figure 1 This is a schematic flowchart of the preparation method of the magnetic fiber composite hydrogel material of the present invention.
[0040] Figure 2 XRD patterns of polylactic acid (PLLA), magnetic nanofibers, and Mn2O3-modified magnetic nanofibers.
[0041] Figure 3 XPS full spectra of polylactic acid (PLLA), magnetic nanofibers, and Mn2O3-modified magnetic nanofibers.
[0042] Figure 4 XPS fine spectra of polylactic acid (PLLA), magnetic nanofibers, and Mn2O3-modified magnetic nanofibers.
[0043] Figure 5 VSM hysteresis loops for polylactic acid (PLLA), magnetic nanofibers, and Mn2O3-modified magnetic nanofibers.
[0044] Figure 6 SEM images of polylactic acid (PLLA), magnetic nanofibers, and Mn2O3-modified magnetic nanofibers.
[0045] Figure 7 Image showing the orientational arrangement of magnetic fibers in a magnetic fiber composite hydrogel.
[0046] Figure 8 Image showing magnetic fiber composite hydrogel on bacterial cellulose BC membrane.
[0047] Figure 9 This is a stress-strain curve. Detailed Implementation
[0048] The technical solution of the present invention will be further described in conjunction with the following embodiments.
[0049] Example 1
[0050] A method for preparing a magnetic fiber composite hydrogel material, such as Figure 1 As shown, magnetic nanofibers were prepared using polylactic acid (PLLA) and iron(III) oxide (Fe3O4) nanoparticles. Then, the surface of the magnetic nanofibers was modified with potassium permanganate (KMnO4) to obtain Mn2O3-modified magnetic nanofibers. Finally, the Mn2O3-modified magnetic nanofibers were composited with methacryloyl fibroin (SilMA), and then, using a bacterial cellulose (BC) membrane as a substrate, combined with magnetic field orientation and ultraviolet light crosslinking technology, a magnetic fiber composite hydrogel material with an ordered structure was constructed.
[0051] The specific preparation method of this magnetic fiber composite hydrogel material includes the following steps:
[0052] S1. Magnetic nanofibers are obtained by electrospinning polylactic acid (PLLA) and iron(III) oxide (Fe3O4) nanoparticles.
[0053] S2. The magnetic nanofibers of S1 were pretreated with dopamine hydrochloride and then reacted with potassium permanganate KMnO4 to obtain Mn2O3 modified magnetic nanofibers.
[0054] S3, magnetic nanofibers modified with photoinitiator, methacrylamide silk fibroin SilMA and S2 Mn2O3 were obtained as a composite precursor solution.
[0055] S4. The composite precursor solution of S3 is cast into a bacterial cellulose BC membrane, and then the magnetic nanofibers are oriented in a magnetic field. Finally, photocrosslinking and curing are performed to obtain a magnetic fiber composite hydrogel material.
[0056] S1 includes the following steps:
[0057] S1.1. Polylactic acid (PLLA) is added to hexafluoroisopropanol (HFIP) to obtain a PLLA solution with a mass concentration of 12% (w / v) to 18% (w / v);
[0058] S1.2 Add Fe3O4 nanoparticles to PLLA solution and ultrasonically disperse for 20 min to 40 min, with the mass concentration of Fe3O4 nanoparticles being 3% (w / v) to 6% (w / v) to obtain spinning solution;
[0059] S1.3. Electrospin the spinning solution of S1.2 using an electrospinning process and collect the fiber membrane.
[0060] S1.4. The fiber membrane from S1.3 is dried, then deionized water is added and the membrane is homogenized and pulverized in a high-speed homogenizer. The amount of deionized water added is 3500 to 4500 times the weight of polylactic acid (PLLA) to obtain the magnetic nanofibers.
[0061] S2 includes the following steps:
[0062] S2.1 Add Tris(hydroxymethylaminomethane) to double-distilled water to obtain a Tris(hydroxymethylaminomethane) solution with a Tris(hydroxymethylaminomethane) mass concentration of 0.5% (w / v) to 0.8% (w / v); then add hydrochloric acid to adjust the pH to 8.0 to 9.0, and proceed to S2.2;
[0063] S2.2 Add dopamine hydrochloride to the tris(hydroxymethyl)aminomethane solution in S2.1, with a mass concentration of 1.8 mg / mL to 2.2 mg / mL, then add the magnetic nanofibers from S1 with a mass concentration of 3% (w / v) to 6% (w / v), stir at room temperature in the dark for 10 to 12 hours, and then centrifuge to collect the precipitate.
[0064] S2.3. Add the precipitate of S2.2 to a potassium permanganate KMnO4 solution with a mass concentration of 0.10% (w / v) to 0.15% (w / v), and the mass concentration of the precipitate of S2.2 in the potassium permanganate solution is 1% (w / v) to 5% (w / v). Then stir at room temperature for 10 h to 12 h, and centrifuge to separate the solid to obtain Mn2O3 modified magnetic nanofibers.
[0065] It should be noted that there are four reasons for adding Tris(hydroxymethyl)aminomethane (Tris), hydrochloric acid, and dopamine hydrochloride to pretreat the magnetic nanofibers S1 in this invention: 1. From the perspective of charge regulation: To construct the charge environment for the electrostatic attraction reaction system between the magnetic nanofibers and Mn2O3, a buffer system with pH=8.5 is formed by mixing Tris and HCl. This pH value is the optimal condition for the self-polymerization of dopamine hydrochloride. In a neutral to weakly alkaline environment (pH 8.0-9.0), the catechol group of dopamine hydrochloride is easily oxidized and dehydrogenated, forming a quinone structure and initiating self-polymerization to generate polydopamine (PDA). The PDA molecular chain contains a large number of amino-NH2 and hydroxyl-OH groups. In the buffer system with pH=8.5, the amino groups undergo partial protonation to form -NH3. + This process introduces a weak positive charge to the PDA layer deposited on the surface of the magnetic nanofibers. This positive charge is matched with the electrostatic attraction of Mn₂O₃, an inorganic metal oxide whose surface readily adsorbs hydroxyl groups (-OH) in aqueous solutions, exhibiting a weak negative charge (in neutral to weakly alkaline environments, the dissociation of surface hydroxyl groups in metal oxides leads to a negative charge). Without PDA modification, the magnetic nanofibers (PLLA@Fe₃O₄) are hydrophobic and neutral, lacking electrostatic interaction with the negatively charged Mn₂O₃, leading to agglomeration or uneven deposition. However, with PDA modification, the positive charge on the fiber surface and the negative charge on the Mn₂O₃ surface form an electrostatic attraction, providing charge anchoring points for the directional deposition of Mn₂O₃, ensuring uniform adhesion of Mn₂O₃ particles to the fiber surface. Figure 2As shown in the SEM image, a rough and uniform Mn2O3 deposition layer is formed on the fiber surface. 2. From the perspective of the adhesion enhancement layer: the interfacial bonding force is improved by the "molecular adhesive" effect of polydopamine PDA. The adhesion mechanism of polydopamine PDA, which is generated by the self-polymerization of dopamine hydrochloride, has unique adhesion characteristics: on the one hand, the catechol groups in the PDA molecule can form covalent bonds (such as transesterification and coordination bonds) or non-covalent bonds (hydrogen bonds and hydrophobic interactions) with the surface of magnetic nanofibers (ester groups of PLLA and hydroxyl groups of Fe3O4), so as to achieve a firm anchoring of the PDA layer on the fiber surface; on the other hand, the abundant amino and hydroxyl groups on the surface of the PDA layer can form multiple interactions (hydrogen bonds, coordination bonds, and electrostatic attraction synergy) with the subsequently added Mn2O3 particles, which significantly enhances the interfacial adhesion strength between Mn2O3 and magnetic nanofibers, and avoids the Mn2O3 layer from falling off during the subsequent preparation of hydrogels or application. This invention addresses the problem in existing technologies where the interfacial bonding between magnetic particles (such as Fe3O4) and inorganic functional layers (such as Mn2O3) is weak and prone to agglomeration, leading to functional failure. The invention utilizes the dual adhesive effect of PDA: ① It firmly adheres to the surface of magnetic nanofibers, forming a stable intermediate transition layer; ② It tightly binds to Mn2O3 particles, transforming Mn2O3 from a free state to a firmly supported state. This solves the problem of uneven Mn2O3 dispersion and improves the structural stability of the composite fiber, laying the foundation for subsequent mechanical enhancement and multifunctional integration (catalysis, electrochemical response, etc.) of the composite hydrogel. 3. From a charge perspective, the weak positive charge of the PDA layer and the weak negative charge of Mn2O3 form an electrostatic attraction, guiding the directional deposition of Mn2O3. 4. From an adhesive perspective, the multiple interactions of PDA enhance the interfacial bonding force between the magnetic nanofibers and Mn2O3, preventing detachment and agglomeration, ultimately achieving the technical goal of stable fiber structure and efficient Mn2O3 function.
[0066] S3 includes the following steps:
[0067] S3.1 Add a photoinitiator to phosphate-buffered saline (PBS) and heat in a water bath at 40°C–50°C in the dark for 10–20 min to obtain an initiator solution with a mass concentration of 0.20% (w / v)–0.30% (w / v); wherein the photoinitiator is lithium phenyl-2,4,6-trimethylbenzoyl phosphate (LAP).
[0068] S3.2 Add methacrylamide silk fibroin SilMA to the initiator solution in S3.1, stir or shake at room temperature in the dark for 0.5 h to 1 h to obtain a SilMA solution with a mass volume concentration of 8% (w / v) to 20% (w / v).
[0069] S3.3 Add the Mn2O3-modified magnetic nanofibers of S2 to the SilMA solution of S3.2 and then mix by shaking to obtain a composite precursor solution. The mass concentration of the Mn2O3-modified magnetic nanofibers in the SilMA solution is 5% (w / v) to 15% (w / v).
[0070] S4 includes the following steps:
[0071] S4.1. The composite precursor solution of S3 is cast onto the surface of the bacterial cellulose BC membrane, and the coating thickness of the composite precursor solution is 1mm to 3mm, to obtain the cast bacterial cellulose BC membrane.
[0072] S4.2 Place the cast bacterial cellulose BC membrane from S4.1 in a magnetic field with an intensity of 20mT to 50mT for 10min to 15min, and then irradiate it with ultraviolet light for 20s to 30s to perform photocrosslinking and curing, thereby obtaining a magnetic fiber composite hydrogel material.
[0073] In S1.3, the parameters of the electrospinning process are: voltage of 12kV to 18kV, receiving distance of 15cm to 20cm, spinning rate of 1.0mL / h to 1.5mL / h, ambient temperature of 25℃ to 30℃, and relative humidity of 40% to 50%.
[0074] Specifically, S1.4 involves drying the fiber membrane of S1.3 at 35℃~40℃ for 12h~15h, then adding deionized water and placing it in a high-speed homogenizer, homogenizing and pulverizing it at a speed of 8000rpm~10000rpm for 15min~20min, centrifuging to separate the precipitate, which is the magnetic nanofiber.
[0075] In step S4.2, the wavelength of the ultraviolet light is 405 nm, and the power is 25 mW / cm². 2 .
[0076] This embodiment is a general process description. Specific parameters can be adjusted by referring to the preferred range or optimal value of embodiments 2-4 below.
[0077] The preparation method of this magnetic fiber composite hydrogel material introduces Fe3O4 nanoparticles into PLLA nanofibers to impart magnetic response properties. An external magnetic field is applied during the composite hydrogel molding stage, causing the magnetic nanofibers to align oriented along the magnetic field direction, achieving an orientation factor of over 80%, effectively simulating the anisotropic microstructure of natural tissues. 4. Significantly improved mechanical properties and anisotropic characteristics: Addressing the problems of weak and isotropic mechanical properties in existing hydrogels, this invention utilizes oriented polylactic acid (PLLA) nanofibers as a reinforcing phase to construct a continuous reinforcing network within a methacryloyl fibroin (SilMA) matrix. Simultaneously, a bacterial cellulose (BC) membrane is used as a substrate to enhance interfacial bonding and stress transfer. This results in a 2-3 times higher tensile strength along the orientation direction compared to pure SilMA hydrogels, meeting the directional mechanical property requirements for load-bearing tissue repair. 5. High functional integration and wide application potential: Existing hydrogels generally have limited functions. This invention uses potassium permanganate oxidation deposition to uniformly modify the surface of magnetic fibers with a Mn2O3 layer, endowing the material with catalytic activity, electrochemical response characteristics, and pH-responsive drug release capability. At the same time, the Fe3O4 component enables the hydrogel to possess magnetocaloric conversion and magnetic resonance imaging potential, expanding the application prospects of the material in multifunctional biomedical fields such as tumor treatment, diagnosis, and intelligent drug delivery.
[0078] Example 2
[0079] A method for preparing a magnetic fiber composite hydrogel material, with other characteristics the same as in Example 1, and specific parameters as follows:
[0080] S1 includes the following steps:
[0081] S1.1. Polylactic acid (PLLA) is added to hexafluoroisopropanol (HFIP) to obtain a PLLA solution with a mass concentration of 12% (w / v);
[0082] S1.2 Add Fe3O4 nanoparticles to PLLA solution and ultrasonically disperse for 40 min, with a mass concentration of Fe3O4 nanoparticles of 6% (w / v) to obtain spinning solution. The particle size range of Fe3O4 nanoparticles is 100 nm to 200 nm.
[0083] S1.3. Electrospinning is performed on the spinning solution of S1.2 using an electrospinning process to collect the fiber membrane. The parameters of the electrospinning process are: voltage of 12kV, receiving distance of 20cm, spinning rate of 1.5mL / h, ambient temperature of 30℃, and relative humidity of 40%.
[0084] S1.4. Dry the fiber membrane from S1.3 at 35°C for 12 hours, then add deionized water, with the amount of deionized water being 3500 times the weight of polylactic acid (PLLA). Place the membrane in a high-speed homogenizer and homogenize it at 8000 rpm for 20 minutes. Centrifuge to separate the precipitate, which is the magnetic nanofiber.
[0085] S2 includes the following steps:
[0086] S2.1 Add Tris(hydroxymethylaminomethane) to double-distilled water to obtain a Tris(hydroxymethylaminomethane) solution with a Tris(hydroxymethylaminomethane) mass concentration of 0.5% (w / v); then add hydrochloric acid to adjust the pH to 8.0, and proceed to S2.2;
[0087] S2.2 Add dopamine hydrochloride to the tris(hydroxymethyl)aminomethane solution in S2.1, with a dopamine hydrochloride concentration of 1.8 mg / mL, and then add the magnetic nanofibers from S1 with a concentration of 3% (w / v). Stir at room temperature in the dark for 10 h, and then centrifuge to collect the precipitate.
[0088] S2.3. Add the precipitate of S2.2 to a potassium permanganate KMnO4 solution with a mass concentration of 0.10% (w / v), and the mass concentration of the precipitate of S2.2 in the potassium permanganate solution is 5% (w / v). Then stir at room temperature for 10 h, and centrifuge to separate the solid to obtain Mn2O3 modified magnetic nanofibers.
[0089] S3 includes the following steps:
[0090] S3.1 Add photoinitiator to phosphate-buffered saline (PBS) solution, and then heat in a 40°C water bath in the dark for 20 min to obtain an initiator solution with a mass concentration of 0.30% (w / v).
[0091] S3.2 Add methacrylamide silk fibroin SilMA to the initiator solution in S3.1, stir or shake at room temperature in the dark for 1 h to obtain a SilMA solution with a mass-volume concentration of 8% (w / v).
[0092] S3.3. Add the Mn2O3-modified magnetic nanofibers of S2 to the SilMA solution of S3.2 and then mix by shaking to obtain a composite precursor solution. The mass concentration of the Mn2O3-modified magnetic nanofibers in the SilMA solution is 5% (w / v).
[0093] S4 includes the following steps:
[0094] S4.1. The composite precursor solution of S3 is cast onto the surface of the bacterial cellulose BC membrane, and the coating thickness of the composite precursor solution is 1 mm, to obtain the cast bacterial cellulose BC membrane.
[0095] S4.2. The cast bacterial cellulose BC membrane from S4.1 was placed in a magnetic field with a strength of 20 mT for 15 min, and then irradiated with ultraviolet light for 20 s to perform photocrosslinking and curing, thus obtaining a magnetic fiber composite hydrogel material. The wavelength of the ultraviolet light was 405 nm, and the power was 25 mW / cm². 2 .
[0096] Example 3
[0097] A method for preparing a magnetic fiber composite hydrogel material, which has the same characteristics as in Example 1, and also has the following characteristics:
[0098] S1 includes the following steps:
[0099] S1.1. Polylactic acid (PLLA) is added to hexafluoroisopropanol (HFIP) to obtain a PLLA solution with a mass concentration of 18% (w / v);
[0100] S1.2 Add Fe3O4 nanoparticles to PLLA solution and ultrasonically disperse for 20 min, with a mass concentration of Fe3O4 nanoparticles of 3% (w / v) to obtain spinning solution. The particle size range of Fe3O4 nanoparticles is 100 nm to 200 nm.
[0101] S1.3. Electrospinning is performed on the spinning solution of S1.2 using an electrospinning process to collect the fiber membrane. The parameters of the electrospinning process are: voltage of 18kV, receiving distance of 15cm, spinning rate of 1.0mL / h, ambient temperature of 25℃, and relative humidity of 50%.
[0102] S1.4. Dry the fiber membrane from S1.3 at 40℃ for 15 hours, then add deionized water, the amount of which is 4500 times the weight of polylactic acid (PLLA). Place it in a high-speed homogenizer and homogenize it at 10000 rpm for 15 minutes. Centrifuge and collect the precipitate, which is the magnetic nanofiber.
[0103] S2 includes the following steps:
[0104] S2.1 Add Tris(hydroxymethylaminomethane) to double-distilled water to obtain a Tris(hydroxymethylaminomethane) solution with a Tris(hydroxymethylaminomethane) mass concentration of 0.8% (w / v); then add hydrochloric acid to adjust the pH to 9.0, and proceed to S2.2;
[0105] S2.2 Add dopamine hydrochloride to the tris(hydroxymethyl)aminomethane solution in S2.1, with a dopamine hydrochloride concentration of 2.2 mg / mL, then add the magnetic nanofibers from S1 with a concentration of 6% (w / v), stir at room temperature in the dark for 12 h, and then centrifuge to collect the precipitate.
[0106] S2.3. Add the precipitate of S2.2 to a potassium permanganate KMnO4 solution with a mass concentration of 0.15% (w / v), and the mass concentration of the precipitate of S2.2 in the potassium permanganate solution is 1% (w / v). Then stir at room temperature for 12 h, and centrifuge to separate the solid to obtain Mn2O3 modified magnetic nanofibers.
[0107] S3 includes the following steps:
[0108] S3.1 Add photoinitiator to phosphate-buffered saline (PBS) solution, and then heat in a 50°C water bath in the dark for 10 min to obtain an initiator solution with a mass concentration of 0.20% (w / v).
[0109] S3.2 Add methacrylamide silk fibroin SilMA to the initiator solution in S3.1, stir or shake at room temperature in the dark for 0.5 h to obtain a SilMA solution with a mass-volume concentration of 20% (w / v).
[0110] S3.3 Add the Mn2O3-modified magnetic nanofibers of S2 to the SilMA solution of S3.2 and then mix by shaking to obtain a composite precursor solution, wherein the mass concentration of the Mn2O3-modified magnetic nanofibers in the SilMA solution is 15% (w / v).
[0111] S4 includes the following steps:
[0112] S4.1. The composite precursor solution of S3 is cast onto the surface of the bacterial cellulose BC membrane, and the coating thickness of the composite precursor solution is 3mm, to obtain the cast bacterial cellulose BC membrane.
[0113] S4.2. The cast bacterial cellulose BC membrane from S4.1 was placed in a magnetic field with a strength of 50 mT for 10 min, and then irradiated with ultraviolet light for 30 s to perform photocrosslinking and curing, thus obtaining a magnetic fiber composite hydrogel material. The wavelength of the ultraviolet light was 405 nm, and the power was 25 mW / cm². 2 .
[0114] Example 4
[0115] A method for preparing a magnetic fiber composite hydrogel material, which has the same characteristics as in Example 1, and also has the following characteristics:
[0116] S1 includes the following steps:
[0117] S1.1. Polylactic acid (PLLA) is added to hexafluoroisopropanol (HFIP) to obtain a PLLA solution with a mass concentration of 15% (w / v);
[0118] S1.2 Add Fe3O4 nanoparticles to PLLA solution and ultrasonically disperse for 30 min, with a mass concentration of 5% (w / v) of Fe3O4 nanoparticles to obtain spinning solution. The particle size range of Fe3O4 nanoparticles is 100 nm to 200 nm.
[0119] S1.3. Electrospinning is performed on the spinning solution of S1.2 using an electrospinning process to collect the fiber membrane. The parameters of the electrospinning process are: voltage of 15kV, receiving distance of 18cm, spinning rate of 1.2mL / h, ambient temperature of 28℃, and relative humidity of 45%.
[0120] S1.4. The fiber membrane of S1.3 is dried at 37°C for 14 hours, then deionized water is added, and the amount of deionized water added is 4000 times the weight of polylactic acid (PLLA). The membrane is placed in a high-speed homogenizer and homogenized at 9000 rpm for 18 minutes. After centrifugation, the precipitate is collected, which is the magnetic nanofiber.
[0121] S2 includes the following steps:
[0122] S2.1 Add Tris(hydroxymethylaminomethane) to double-distilled water to obtain a Tris(hydroxymethylaminomethane) solution with a Tris(hydroxymethylaminomethane) mass concentration of 0.6057% (w / v); then add hydrochloric acid to adjust the pH to 8.5, and proceed to S2.2;
[0123] S2.2 Add dopamine hydrochloride to the tris(hydroxymethyl)aminomethane solution in S2.1, with a dopamine hydrochloride concentration of 2.0 mg / mL, then add the magnetic nanofibers from S1 with a concentration of 5% (w / v), stir at room temperature in the dark for 11 h, and then centrifuge to collect the precipitate.
[0124] S2.3. Add the precipitate of S2.2 to a potassium permanganate KMnO4 solution with a mass concentration of 0.13% (w / v), and the mass concentration of the precipitate of S2.2 in the potassium permanganate solution is 3% (w / v). Then stir at room temperature for 11 h, and centrifuge to separate the solid to obtain Mn2O3 modified magnetic nanofibers.
[0125] S3 includes the following steps:
[0126] S3.1 Add photoinitiator to phosphate-buffered saline (PBS) solution, and then heat in a 45°C water bath in the dark for 15 min to obtain an initiator solution with a mass concentration of 0.25% (w / v).
[0127] S3.2 Add methacrylamide silk fibroin SilMA to the initiator solution in S3.1, stir or shake at room temperature in the dark for 0.6 h to obtain a SilMA solution with a mass-volume concentration of 13% (w / v).
[0128] S3.3. Add the Mn2O3-modified magnetic nanofibers of S2 to the SilMA solution of S3.2 and then mix by shaking to obtain a composite precursor solution. The mass concentration of the Mn2O3-modified magnetic nanofibers in the SilMA solution is 10% (w / v).
[0129] S4 includes the following steps:
[0130] S4.1. The composite precursor solution of S3 is cast onto the surface of the bacterial cellulose BC membrane, and the coating thickness of the composite precursor solution is 2 mm, to obtain the cast bacterial cellulose BC membrane.
[0131] S4.2. The cast bacterial cellulose BC membrane from S4.1 was placed in a magnetic field with a strength of 40 mT for 12 min, and then irradiated with ultraviolet light for 25 s to perform photocrosslinking and curing, thus obtaining a magnetic fiber composite hydrogel material. The wavelength of the ultraviolet light was 405 nm, and the power was 25 mW / cm². 2 .
[0132] Comparative Example 1
[0133] The preparation method of Comparative Sample 1 is the same as that of Example 4, except that Mn2O3 modification was not performed, bacterial cellulose BC membrane was not used as a substrate, and magnetic field-induced orientation was not applied. This was used to compare and verify the role of each key process, specifically:
[0134] S1 includes the following steps:
[0135] S1.1. Polylactic acid (PLLA) is added to hexafluoroisopropanol (HFIP) to obtain a PLLA solution with a mass concentration of 15% (w / v);
[0136] S1.2 Add Fe3O4 nanoparticles to PLLA solution and ultrasonically disperse for 30 min, with a mass concentration of 5% (w / v) of Fe3O4 nanoparticles to obtain spinning solution. The particle size range of Fe3O4 nanoparticles is 100 nm to 200 nm.
[0137] S1.3. Electrospinning is performed on the spinning solution of S1.2 using an electrospinning process to collect the fiber membrane. The parameters of the electrospinning process are: voltage of 15kV, receiving distance of 18cm, spinning rate of 1.2mL / h, ambient temperature of 28℃, and relative humidity of 45%.
[0138] S1.4. The fiber membrane of S1.3 is dried at 37°C for 14 hours, then deionized water is added, and the amount of deionized water added is 4000 times the weight of polylactic acid (PLLA). The membrane is placed in a high-speed homogenizer and homogenized at 9000 rpm for 18 minutes. After centrifugation, the precipitate is collected, which is the magnetic nanofiber.
[0139] S2 includes the following steps:
[0140] S2.1 Add photoinitiator to phosphate-buffered saline (PBS) solution, and then heat in a 45°C water bath in the dark for 15 min to obtain an initiator solution with a mass concentration of 0.25% (w / v).
[0141] S2.2 Add methacrylamide silk fibroin (SilMA) to the initiator solution in S2.1, stir or shake at room temperature in the dark for 0.6 h to obtain a SilMA solution with a mass-volume concentration of 13% (w / v).
[0142] S2.3. Add the magnetic nanofibers of S1 to the SilMA solution of S2.2 and then mix by shaking to obtain a composite precursor solution, wherein the mass concentration of the magnetic nanofibers in the SilMA solution is 10% (w / v).
[0143] Specifically, in S3, the composite precursor solution was photocrosslinked and cured to obtain a magnetic fiber composite hydrogel, i.e., control sample 1. The wavelength of the ultraviolet light was 405 nm, and the power was 25 mW / cm². 2 .
[0144] Comparative Example 2
[0145] The preparation method of Comparative Sample 2 is the same as that of Example 4, except that Mn2O3 modification was not performed and bacterial cellulose (BC) membrane was not used as a substrate. Specifically:
[0146] S1 includes the following steps:
[0147] S1.1. Polylactic acid (PLLA) is added to hexafluoroisopropanol (HFIP) to obtain a PLLA solution with a mass concentration of 15% (w / v);
[0148] S1.2 Add Fe3O4 nanoparticles to PLLA solution and ultrasonically disperse for 30 min, with a mass concentration of 5% (w / v) of Fe3O4 nanoparticles to obtain spinning solution. The particle size range of Fe3O4 nanoparticles is 100 nm to 200 nm.
[0149] S1.3. Electrospinning is performed on the spinning solution of S1.2 using an electrospinning process to collect the fiber membrane. The parameters of the electrospinning process are: voltage of 15kV, receiving distance of 18cm, spinning rate of 1.2mL / h, ambient temperature of 28℃, and relative humidity of 45%.
[0150] S1.4. The fiber membrane of S1.3 is dried at 37°C for 14 hours, then deionized water is added, and the amount of deionized water added is 4000 times the weight of polylactic acid (PLLA). The membrane is placed in a high-speed homogenizer and homogenized at 9000 rpm for 18 minutes. After centrifugation, the precipitate is collected, which is the magnetic nanofiber.
[0151] S2 includes the following steps:
[0152] S2.1 Add photoinitiator to phosphate-buffered saline (PBS) solution, and then heat in a 45°C water bath in the dark for 15 min to obtain an initiator solution with a mass concentration of 0.25% (w / v).
[0153] S2.2 Add methacrylamide silk fibroin (SilMA) to the initiator solution in S2.1, stir or shake at room temperature in the dark for 0.6 h to obtain a SilMA solution with a mass-volume concentration of 13% (w / v).
[0154] S2.3. Add the magnetic nanofibers of S1 to the SilMA solution of S2.2 and then mix by shaking to obtain a composite precursor solution, wherein the mass concentration of the magnetic nanofibers in the SilMA solution is 10% (w / v).
[0155] Specifically, in S3, the composite precursor liquid was placed in a magnetic field with a strength of 50 mT and maintained for 10 min to perform photocrosslinking and curing, resulting in control sample 2. The wavelength of the ultraviolet light was 405 nm, and the power was 25 mW / cm². 2 Magnetic fiber composite hydrogel was obtained, namely control sample 2.
[0156] Comparative Example 3
[0157] The preparation method of Comparative Sample 3 is the same as that of Example 4, except that bacterial cellulose BC membrane was not used as a substrate and no magnetic field was applied to induce orientation. Specifically:
[0158] S1 includes the following steps:
[0159] S1.1. Polylactic acid (PLLA) is added to hexafluoroisopropanol (HFIP) to obtain a PLLA solution with a mass concentration of 15% (w / v);
[0160] S1.2 Add Fe3O4 nanoparticles to PLLA solution and ultrasonically disperse for 30 min, with a mass concentration of 5% (w / v) of Fe3O4 nanoparticles to obtain spinning solution. The particle size range of Fe3O4 nanoparticles is 100 nm to 200 nm.
[0161] S1.3. Electrospinning is performed on the spinning solution of S1.2 using an electrospinning process to collect the fiber membrane. The parameters of the electrospinning process are: voltage of 15kV, receiving distance of 18cm, spinning rate of 1.2mL / h, ambient temperature of 28℃, and relative humidity of 45%.
[0162] S1.4. The fiber membrane of S1.3 is dried at 37°C for 14 hours, then deionized water is added, and the amount of deionized water added is 4000 times the weight of polylactic acid (PLLA). The membrane is placed in a high-speed homogenizer and homogenized at 9000 rpm for 18 minutes. After centrifugation, the precipitate is collected, which is the magnetic nanofiber.
[0163] S2 includes the following steps:
[0164] S2.1 Add Tris(hydroxymethylaminomethane) to double-distilled water to obtain a Tris(hydroxymethylaminomethane) solution with a Tris(hydroxymethylaminomethane) mass concentration of 0.6057% (w / v); then add hydrochloric acid to adjust the pH to 8.5, and proceed to S2.2;
[0165] S2.2 Add dopamine hydrochloride to the tris(hydroxymethyl)aminomethane solution in S2.1, with a dopamine hydrochloride concentration of 2.0 mg / mL, then add the magnetic nanofibers from S1 with a concentration of 5% (w / v), stir at room temperature in the dark for 11 h, and then centrifuge to collect the precipitate.
[0166] S2.3. Add the precipitate of S2.2 to a potassium permanganate KMnO4 solution with a mass concentration of 0.13% (w / v), and the mass concentration of the precipitate of S2.2 in the potassium permanganate solution is 3% (w / v). Then stir at room temperature for 11 h, and centrifuge to separate the solid to obtain Mn2O3 modified magnetic nanofibers.
[0167] S3 includes the following steps:
[0168] S3.1 Add photoinitiator to phosphate-buffered saline (PBS) solution, and then heat in a 45°C water bath in the dark for 15 min to obtain an initiator solution with a mass concentration of 0.25% (w / v).
[0169] S3.2 Add methacrylamide silk fibroin SilMA to the initiator solution in S3.1, stir or shake at room temperature in the dark for 0.6 h to obtain a SilMA solution with a mass-volume concentration of 13% (w / v).
[0170] S3.3. Add the Mn2O3-modified magnetic nanofibers of S2 to the SilMA solution of S3.2 and then mix by shaking to obtain a composite precursor solution. The mass concentration of the Mn2O3-modified magnetic nanofibers in the SilMA solution is 10% (w / v).
[0171] Specifically, S4 involves irradiating the composite precursor solution of S3 with ultraviolet light for 25 seconds to achieve photocrosslinking and curing, resulting in a magnetic fiber composite hydrogel, i.e., control sample 3. The wavelength of the ultraviolet light was 405 nm, and the power was 25 mW / cm². 2 .
[0172] Comparative Example 4
[0173] The preparation method of Comparative Sample 4 is the same as that of Example 4, except that bacterial cellulose BC membrane was not used as a substrate. Specifically:
[0174] S1 includes the following steps:
[0175] S1.1. Polylactic acid (PLLA) is added to hexafluoroisopropanol (HFIP) to obtain a PLLA solution with a mass concentration of 15% (w / v);
[0176] S1.2 Add Fe3O4 nanoparticles to PLLA solution and ultrasonically disperse for 30 min, with a mass concentration of 5% (w / v) of Fe3O4 nanoparticles to obtain spinning solution. The particle size range of Fe3O4 nanoparticles is 100 nm to 200 nm.
[0177] S1.3. Electrospinning is performed on the spinning solution of S1.2 using an electrospinning process to collect the fiber membrane. The parameters of the electrospinning process are: voltage of 15kV, receiving distance of 18cm, spinning rate of 1.2mL / h, ambient temperature of 28℃, and relative humidity of 45%.
[0178] S1.4. The fiber membrane of S1.3 is dried at 37°C for 14 hours, then deionized water is added, and the amount of deionized water added is 4000 times the weight of polylactic acid (PLLA). The membrane is placed in a high-speed homogenizer and homogenized at 9000 rpm for 18 minutes. After centrifugation, the precipitate is collected, which is the magnetic nanofiber.
[0179] S2 includes the following steps:
[0180] S2.1 Add Tris(hydroxymethylaminomethane) to double-distilled water to obtain a Tris(hydroxymethylaminomethane) solution with a Tris(hydroxymethylaminomethane) mass concentration of 0.6057% (w / v); then add hydrochloric acid to adjust the pH to 8.5, and proceed to S2.2;
[0181] S2.2 Add dopamine hydrochloride to the tris(hydroxymethyl)aminomethane solution in S2.1, with a dopamine hydrochloride concentration of 2.0 mg / mL, then add the magnetic nanofibers from S1 with a concentration of 5% (w / v), stir at room temperature in the dark for 11 h, and then centrifuge to collect the precipitate.
[0182] S2.3. Add the precipitate of S2.2 to a potassium permanganate KMnO4 solution with a mass concentration of 0.13% (w / v), and the mass concentration of the precipitate of S2.2 in the potassium permanganate solution is 3% (w / v). Then stir at room temperature for 11 h, and centrifuge to separate the solid to obtain Mn2O3 modified magnetic nanofibers.
[0183] S3 includes the following steps:
[0184] S3.1 Add photoinitiator to phosphate-buffered saline (PBS) solution, and then heat in a 45°C water bath in the dark for 15 min to obtain an initiator solution with a mass concentration of 0.25% (w / v).
[0185] S3.2 Add methacrylamide silk fibroin SilMA to the initiator solution in S3.1, stir or shake at room temperature in the dark for 0.6 h to obtain a SilMA solution with a mass-volume concentration of 13% (w / v).
[0186] S3.3. Add the Mn2O3-modified magnetic nanofibers of S2 to the SilMA solution of S3.2 and then mix by shaking to obtain a composite precursor solution. The mass concentration of the Mn2O3-modified magnetic nanofibers in the SilMA solution is 10% (w / v).
[0187] Specifically, S4 involved placing the composite precursor solution from S3 in a magnetic field of 40 mT for 12 minutes, followed by UV irradiation for 25 seconds to achieve photocrosslinking and curing, resulting in the magnetic fiber composite hydrogel, i.e., control sample 4. The UV light wavelength was 405 nm, and the power was 25 mW / cm². 2 .
[0188] Comparative Example 5
[0189] The preparation method of Comparative Sample 5 is the same as that of Example 4, except that no magnetic field was applied in S4.2 to induce orientation, thus obtaining Comparative Sample 5.
[0190] Comparative Example 6
[0191] The preparation method of Comparative Sample 6 is the same as that of Example 4, except that Fe3O4 nanoparticles were not added and Mn2O3 modification was not performed. The specific preparation steps are as follows:
[0192] Specifically, S1 is:
[0193] S1.1. Polylactic acid (PLLA) is added to hexafluoroisopropanol (HFIP) to obtain a PLLA solution with a mass concentration of 15% (w / v);
[0194] S1.2. Electrospinning is performed on the spinning solution of S1.1 using an electrospinning process to collect the fiber membrane. The parameters of the electrospinning process are: voltage of 15kV, receiving distance of 18cm, spinning rate of 1.2mL / h, ambient temperature of 28℃, and relative humidity of 45%.
[0195] S1.3. The fiber membrane from S1.2 is dried at 37°C for 14 hours, then deionized water is added, with the amount of deionized water being 4000 times the weight of polylactic acid (PLLA). The membrane is then placed in a high-speed homogenizer and homogenized at 9000 rpm for 18 minutes. After centrifugation, the precipitate is collected, which is the non-magnetic nanofiber.
[0196] Specifically, S2 is:
[0197] S2.1 Add photoinitiator to phosphate-buffered saline (PBS) solution, and then heat in a 45°C water bath in the dark for 15 min to obtain an initiator solution with a mass concentration of 0.25% (w / v).
[0198] S2.2 Add methacrylamide silk fibroin (SilMA) to the initiator solution in S2.1, stir or shake at room temperature in the dark for 0.6 h to obtain a SilMA solution with a mass-volume concentration of 13% (w / v).
[0199] S2.3. Add the non-magnetic nanofibers of S2 to the SilMA solution of S2.2 and then mix by shaking to obtain a composite precursor solution, wherein the mass concentration of the non-magnetic nanofibers in the SilMA solution is 10% (w / v).
[0200] Specifically, S3 involves casting the composite solution of S2 onto the surface of a bacterial cellulose (BC) membrane, with a coating thickness of 2 mm for the composite precursor solution, to obtain a cast bacterial cellulose (BC) membrane. This membrane is then photocrosslinked and cured by irradiation with ultraviolet light for 25 seconds to obtain a non-magnetic fiber composite hydrogel, i.e., control sample 6. The wavelength of the ultraviolet light is 405 nm, and the power is 25 mW / cm². 2 .
[0201] Comparative Example 7
[0202] The preparation method of Comparative Sample 7 is the same as that of Example 4, except that polylactic acid (PLLA) and Fe3O4 nanoparticles were not added, Mn2O3 modification was not performed, and magnetic field-induced orientation was not applied. The specific preparation steps are as follows:
[0203] S1. Add photoinitiator to phosphate-buffered saline (PBS) solution, and then heat in a 45°C water bath in the dark for 15 min to obtain an initiator solution with a mass concentration of 0.25% (w / v).
[0204] S2. Add methacrylamide silk fibroin (SilMA) to the initiator solution in S1, stir or shake at room temperature in the dark for 0.6 h to obtain a SilMA solution with a mass-volume concentration of 13% (w / v).
[0205] S3. The SilMA solution from S2 was cast onto the surface of a bacterial cellulose (BC) membrane, with a composite precursor solution coating thickness of 2 mm, to obtain a cast bacterial cellulose (BC) membrane. The cast bacterial cellulose (BC) membrane was placed in a magnetic field with a strength of 40 mT for 12 min, and then irradiated with ultraviolet light for 25 s for photocrosslinking and curing, resulting in control sample 7. The wavelength of the ultraviolet light was 405 nm, and the power was 25 mW / cm². 2 .
[0206] Comparative Example 8
[0207] The preparation method of Comparative Sample 8 is the same as that of Example 4, except that it is not modified with Mn2O3 and no magnetic field is applied to induce orientation. The specific preparation steps are as follows:
[0208] S1 includes the following steps:
[0209] S1.1. Polylactic acid (PLLA) is added to hexafluoroisopropanol (HFIP) to obtain a PLLA solution with a mass concentration of 15% (w / v);
[0210] S1.2 Add Fe3O4 nanoparticles to PLLA solution and ultrasonically disperse for 30 min, with a mass concentration of 5% (w / v) of Fe3O4 nanoparticles to obtain spinning solution. The particle size range of Fe3O4 nanoparticles is 100 nm to 200 nm.
[0211] S1.3. Electrospinning is performed on the spinning solution of S1.2 using an electrospinning process to collect the fiber membrane. The parameters of the electrospinning process are: voltage of 15kV, receiving distance of 18cm, spinning rate of 1.2mL / h, ambient temperature of 28℃, and relative humidity of 45%.
[0212] S1.4. The fiber membrane of S1.3 is dried at 37°C for 14 hours, then deionized water is added, and the amount of deionized water added is 4000 times the weight of polylactic acid (PLLA). The membrane is placed in a high-speed homogenizer and homogenized at 9000 rpm for 18 minutes. After centrifugation, the precipitate is collected, which is the magnetic nanofiber.
[0213] S2 includes the following steps:
[0214] S2.1 Add photoinitiator to phosphate-buffered saline (PBS) solution, and then heat in a 45°C water bath in the dark for 15 min to obtain an initiator solution with a mass concentration of 0.25% (w / v).
[0215] S2.2 Add methacrylamide silk fibroin (SilMA) to the initiator solution in S2.1, stir or shake at room temperature in the dark for 0.6 h to obtain a SilMA solution with a mass-volume concentration of 13% (w / v).
[0216] S2.3. Add the magnetic nanofibers of S2 to the SilMA solution of S2.2 and then mix by shaking to obtain a composite precursor solution, wherein the mass concentration of the magnetic nanofibers in the SilMA solution is 10% (w / v).
[0217] S3 includes the following steps:
[0218] S3.1. The composite precursor solution of S2 is cast onto the surface of the bacterial cellulose BC membrane, and the coating thickness of the composite precursor solution is 2 mm, to obtain the cast bacterial cellulose BC membrane.
[0219] S3.2. The cast bacterial cellulose BC membrane from S3.1 was photocrosslinked and cured to obtain control sample 8. The wavelength of the ultraviolet light was 405 nm, and the power was 25 mW / cm². 2 .
[0220] Comparative Example 9
[0221] The preparation method of Comparative Sample 9 is the same as that of Comparative Sample 8 in other aspects, except that in S3.2, the cast bacterial cellulose BC membrane of S3.1 is placed in a magnetic field with an intensity of 40mT and kept for 12min, and then irradiated with ultraviolet light for 25s to perform photocrosslinking and curing to obtain Comparative Sample 9.
[0222] Example of effect
[0223] 1. XRD Analysis
[0224] The sample of Comparative Example 6 (in) Figure 5XRD tests were performed on the magnetic short nanofibers obtained in S1 of the present invention (denoted as PLLA), the magnetic short nanofibers obtained in S2 of the present invention (denoted as PLLA@Fe3O4 in the figure), and the Mn2O3 modified magnetic short nanofibers obtained in S2 of the present invention (denoted as PLLA@Fe3O4-Mn2O3 in the figure), and the results were obtained. Figure 2 .
[0225] from Figure 2 The characteristic crystallization peaks of PLLA, the characteristic peaks of Fe3O4, and the characteristic diffraction peaks of Mn2O3 can be clearly observed in sequence, proving that Fe3O4 and Mn2O3 have been successfully composited in the fiber without destroying the main crystal structure of PLLA, thus realizing the effective construction of multifunctional materials.
[0226] 2. XPS Analysis
[0227] Comparison sample 6 (in) Figure 5 (Referring to PLLA), the magnetic nanofibers obtained in S1 of this invention (in) Figure 5 (referred to as PLLA@Fe3O4) and the Mn2O3 modified magnetic nanofibers obtained in S2 of the present invention (in) Figure 5 XPS testing was performed on a sample labeled PLLA@Fe3O4-Mn2O3, and the results were obtained. Figure 3 and Figure 4 .
[0228] pass Figure 3 and Figure 4 The chemical composition and surface state of the material were jointly verified using XPS analysis. Figure 3 The full spectrum shows the successful introduction of Fe and Mn elements; Figure 4 Fine spectroscopy further confirmed that Mn is stably bound to the fiber surface in the Mn2O3 oxidized state, verifying the successful construction of the composite material and the surface functionalization modification.
[0229] 4. VSM Hysteresis Analysis
[0230] Comparison sample 6 (in) Figure 5 (Referring to PLLA), the magnetic nanofibers obtained in S1 of this invention (in) Figure 5 (referred to as PLLA@Fe3O4) and the Mn2O3 modified magnetic nanofibers obtained in S2 of the present invention (in) Figure 5 Hysteresis analysis was performed on PLLA@Fe3O4-Mn2O3 (denoted as PLLA@Fe3O4-Mn2O3) to obtain... Figure 5 .
[0231] pass Figure 5It is evident that pure PLLA is non-magnetic; PLLA@Fe3O4 exhibits obvious ferromagnetic properties with significant saturation magnetization; after modification with Mn2O3, the magnetization decreases slightly, but still maintains good magnetic responsiveness, proving that the modification with Mn2O3 does not significantly affect the magnetism of the material, providing a basis for subsequent magnetic field-induced orientation alignment.
[0232] 5. SEM Analysis
[0233] Comparison sample 6 (in) Figure 6 (Referring to PLLA), the magnetic nanofibers obtained in S1 of this invention (in) Figure 6 (denoted as PLLA@Fe3O4) and the Mn2O3 modified magnetic nanofibers obtained in S2 of the present invention ( Figure 6 SEM analysis was performed on the sample (denoted as PLLA@Fe3O4-Mn2O3) to obtain... Figure 6 .
[0234] pass Figure 6 It can be seen that the surface of PLLA fibers is smooth; after adding Fe3O4, the surface becomes rough and the particle distribution is uniform; after Mn2O 33 After modification, a uniform nanoparticle layer was formed on the fiber surface, indicating that Mn2O3 had been successfully and uniformly deposited on the fiber surface, enhancing the interfacial bonding and functional integration capabilities.
[0235] 6. Appearance analysis of magnetic fiber composite hydrogel
[0236] Compare the appearance of comparison samples 1-4 to obtain the following results. Figure 7 .
[0237] pass Figure 7 As can be seen, the nanofibers of the magnetic fiber composite hydrogel material of the present invention are arranged in an orderly manner along a single direction.
[0238] 7. Appearance analysis of magnetic fiber composite hydrogel in bacterial cellulose BC membrane
[0239] A comparison of the appearance of the magnetic fiber composite hydrogel materials obtained in Comparison Sample 5 and Example 4 was conducted, and the results were obtained... Figure 8 .
[0240] pass Figure 8 As can be seen, the nanofibers of the magnetic fiber composite hydrogel material of the present invention are arranged in an orderly manner along a single direction.
[0241] 8. Stress-strain analysis
[0242] Stress-strain analysis was performed on the individual bacterial cellulose BC membrane, control samples 5-9, and the magnetic fiber composite hydrogel material of this invention to obtain stress-strain curves, as shown below. Figure 9 Among them, the bacterial cellulose BC membrane alone... Figure 9 The middle part is denoted as BC, compared with sample 7. Figure 9 The Chinese text is denoted as SilMA, and the comparison sample 6 is in... Figure 9 The Chinese text refers to it as PLLA, and the comparison sample 8 is in... Figure 9 The middle sample is denoted as PLLA@Fe3O4(MF-), and the control sample 9 is denoted as... Figure 9 PLLA@Fe3O4(MF+) in the middle, compared with sample 5 in Figure 9 The sample in Example 4 is labeled PLLA@Fe3O4-Mn2O3(MF-). Figure 9 It is denoted as PLLA@Fe3O4-Mn2O3(MF+).
[0243] The stress-strain curve of this invention was tested using a universal testing machine to verify the mechanical properties of the magnetic fiber composite hydrogel. The specific method was as follows: First, the prepared hydrogel sample was cut into pieces 4 cm long and 1 cm wide. Then, both ends of the sample were clamped in the testing machine fixture, and a tensile rate of 5 mm / min was set for uniaxial tensile testing at room temperature. During the test, the system recorded load and displacement data in real time and calculated stress (load / initial cross-sectional area) and strain (displacement / original gauge length) using formulas, automatically plotting the stress-strain curve. The test continued until the sample completely fractured. Finally, key parameters such as tensile strength, elastic modulus, and elongation at break in the parallel / perpendicular orientation directions were obtained through curve analysis to quantify the anisotropic reinforcement effect and structural stability of the material.
[0244] pass Figure 9 Stress-strain curves of different composite hydrogel materials are shown. Compared with pure BC and pure SilMA, the composite hydrogel with Mn2O3-modified magnetic nanofibers exhibits higher tensile strength and elongation at break, indicating that fiber reinforcement significantly improves the mechanical properties of the material. Further comparison shows that the composite hydrogel with magnetically induced orientation exhibits significantly better mechanical properties parallel to the orientation direction than the sample with randomly distributed fibers, proving that the orientation structure further enhances the anisotropic mechanical response of the material and achieves a superior structural strengthening effect.
[0245] In summary, the magnetic fiber composite hydrogel material of this invention exhibits significantly enhanced and anisotropic mechanical properties. The tensile strength parallel to the orientation direction of the composite hydrogel is 2-3 times higher than that of pure SilMA hydrogel, and the mechanical properties differ significantly between the parallel and perpendicular orientation directions. Furthermore, the magnetic nanofibers in the magnetic fiber composite hydrogel material of this invention are oriented along the magnetic field direction, with an orientation factor exceeding 80%, effectively mimicking the anisotropic microstructure of natural tissues. The above structure demonstrates that the magnetic fiber composite hydrogel material has a uniformly modified Mn2O3 layer on the surface of the magnetic fibers, thereby endowing the material with catalytic activity, electrochemical response characteristics, and pH-responsive drug release capability.
[0246] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.
Claims
1. A method for preparing a magnetic fiber composite hydrogel material, characterized in that: Magnetic short nanofibers were prepared by using polylactic acid (PLLA) and iron(III) oxide (Fe3O4) nanoparticles. Then, the surface of the magnetic short nanofibers was modified with potassium permanganate (KMnO4) to obtain Mn2O3-modified magnetic short nanofibers. Finally, the Mn2O3-modified magnetic short nanofibers were composited with methacryloyl fibroin (SilMA), and a bacterial cellulose (BC) membrane was used as a substrate. Combined with magnetic field orientation and ultraviolet light crosslinking technology, a magnetic fiber composite hydrogel material with an ordered structure was constructed.
2. The method for preparing the magnetic fiber composite hydrogel material according to claim 1, characterized in that, Includes the following steps: S1. Magnetic nanofibers are obtained by electrospinning polylactic acid (PLLA) and iron(III) oxide (Fe3O4) nanoparticles. S2. The magnetic nanofibers of S1 were pretreated with dopamine hydrochloride and then reacted with potassium permanganate KMnO4 to obtain Mn2O3 modified magnetic nanofibers. S3, magnetic nanofibers modified with photoinitiator, methacrylamide silk fibroin SilMA and S2 Mn2O3 were obtained as a composite precursor solution. S4. The composite precursor solution of S3 is cast into a bacterial cellulose BC membrane, and then the magnetic nanofibers are oriented in a magnetic field. Finally, photocrosslinking and curing are performed to obtain a magnetic fiber composite hydrogel material.
3. The method for preparing the magnetic fiber composite hydrogel material according to claim 2, characterized in that, S1 includes the following steps: S1.
1. Polylactic acid (PLLA) is added to hexafluoroisopropanol (HFIP) to obtain a PLLA solution with a mass concentration of 12% (w / v) to 18% (w / v); S1.2 Add Fe3O4 nanoparticles to PLLA solution and ultrasonically disperse for 20 min to 40 min, with the mass concentration of Fe3O4 nanoparticles being 3% (w / v) to 6% (w / v) to obtain spinning solution; S1.
3. Electrospin the spinning solution of S1.2 using an electrospinning process and collect the fiber membrane. S1.
4. The fiber membrane from S1.3 is dried, then deionized water is added and the membrane is homogenized and pulverized in a high-speed homogenizer. The amount of deionized water added is 3500 to 4500 times the weight of polylactic acid (PLLA) to obtain the magnetic nanofibers.
4. The method for preparing the magnetic fiber composite hydrogel material according to claim 3, characterized in that, S2 includes the following steps: S2.1 Add Tris(hydroxymethylaminomethane) to double-distilled water to obtain a Tris(hydroxymethylaminomethane) solution with a Tris(hydroxymethylaminomethane) mass concentration of 0.5% (w / v) to 0.8% (w / v); then add hydrochloric acid to adjust the pH to 8.0 to 9.0, and proceed to S2.2; S2.2 Add dopamine hydrochloride to the tris(hydroxymethyl)aminomethane solution in S2.1, with a mass concentration of 1.8 mg / mL to 2.2 mg / mL, then add the magnetic nanofibers from S1 with a mass concentration of 3% (w / v) to 6% (w / v), stir at room temperature in the dark for 10 to 12 hours, and then centrifuge to collect the precipitate. S2.
3. Add the precipitate of S2.2 to a potassium permanganate KMnO4 solution with a mass concentration of 0.10% (w / v) to 0.15% (w / v), and the mass concentration of the precipitate of S2.2 in the potassium permanganate solution is 1% (w / v) to 5% (w / v). Then stir at room temperature for 10 h to 12 h, and centrifuge to separate the solid to obtain Mn2O3 modified magnetic nanofibers.
5. The method for preparing the magnetic fiber composite hydrogel material according to any one of claims 1 to 4, characterized in that, S3 includes the following steps: S3.1 Add photoinitiator to phosphate-buffered saline (PBS) solution, and then heat in a water bath at 40℃~50℃ in the dark for 10min~20min to obtain an initiator solution with a mass concentration of 0.20% (w / v)~0.30% (w / v); S3.2 Add methacrylamide silk fibroin SilMA to the initiator solution in S3.1, stir or shake at room temperature in the dark for 0.5 h to 1 h to obtain a SilMA solution with a mass volume concentration of 8% (w / v) to 20% (w / v). S3.3 Add the Mn2O3-modified magnetic nanofibers of S2 to the SilMA solution of S3.2 and then mix by shaking to obtain a composite precursor solution. The mass concentration of the Mn2O3-modified magnetic nanofibers in the SilMA solution is 5% (w / v) to 15% (w / v).
6. The method for preparing the magnetic fiber composite hydrogel material according to claim 5, characterized in that: S4 includes the following steps: S4.
1. The composite precursor solution of S3 is cast onto the surface of the bacterial cellulose BC membrane, and the coating thickness of the composite precursor solution is 1mm to 3mm, to obtain the cast bacterial cellulose BC membrane. S4.2 Place the cast bacterial cellulose BC membrane from S4.1 in a magnetic field with an intensity of 20mT to 50mT for 10min to 15min, and then irradiate it with ultraviolet light for 20s to 30s to perform photocrosslinking and curing, thereby obtaining a magnetic fiber composite hydrogel material.
7. The method for preparing the magnetic fiber composite hydrogel material according to claim 6, characterized in that: In S1.3, the parameters of the electrospinning process are: voltage of 12kV to 18kV, receiving distance of 15cm to 20cm, spinning rate of 1.0mL / h to 1.5mL / h, ambient temperature of 25℃ to 30℃, and relative humidity of 40% to 50%. Specifically, S1.4 involves drying the fiber membrane of S1.3 at 35℃~40℃ for 12h~15h, then adding deionized water and placing it in a high-speed homogenizer, homogenizing and pulverizing it at a speed of 8000rpm~10000rpm for 15min~20min, centrifuging to separate the precipitate, which is the magnetic nanofiber.
8. The method for preparing the magnetic fiber composite hydrogel material according to any one of claims 1 to 4, characterized in that: The photoinitiator is lithium phenyl-2,4,6-trimethylbenzoyl phosphate (LAP).
9. The method for preparing the magnetic fiber composite hydrogel material according to claim 6, characterized in that: In step S4.2, the wavelength of the ultraviolet light is 405 nm, and the power is 25 mW / cm². 2 .
10. A magnetic fiber composite hydrogel material, characterized in that: It is prepared by the method for preparing magnetic fiber composite hydrogel material according to any one of claims 1 to 9.