Nanofiber scaffold and preparation method thereof
By combining glutaraldehyde vapor crosslinking and thermal crosslinking, the problems of loose structure and rough appearance of nanofiber scaffolds were solved, and nanofiber scaffolds with good structural stability and appearance quality were prepared, which are suitable for biomedical materials.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HUIZHOU HUAYANG MEDICAL EQUIP
- Filing Date
- 2024-11-08
- Publication Date
- 2026-05-12
AI Technical Summary
Existing nanofiber scaffolds suffer from loose structure and rough appearance, making it difficult to meet the requirements of biomedical materials.
The nanofiber membrane was pretreated by a combination of glutaraldehyde vapor crosslinking and thermal crosslinking. The crosslinked nanofiber material was then homogeneously dispersed in a freeze-drying solvent containing tert-butanol and water, and freeze-dried and vacuum-dried to form a stable three-dimensional structure.
It improves the structural stability and appearance quality of nanofiber scaffolds, reduces the risk of deformation during vacuum drying, and is suitable for biomedical materials.
Smart Images
Figure CN122005950A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of biomedical materials technology, and more specifically, to a nanofiber scaffold and its preparation method. Background Technology
[0002] Currently, three-dimensional nanofiber scaffolds are widely used in the field of biomedical materials. Typically, three-dimensional nanofiber scaffolds are prepared by homogenizing and pulverizing electrospun nanofiber membranes, followed by freeze-drying and vacuum drying.
[0003] However, the nanofiber scaffolds currently produced are prone to problems such as loose structure and rough appearance. Summary of the Invention
[0004] To address the aforementioned shortcomings, this application provides a nanofiber scaffold and its preparation method to improve the quality of the nanofiber scaffold.
[0005] This application is implemented as follows:
[0006] In a first aspect, an example of this application provides a method for preparing a nanofiber scaffold, comprising:
[0007] Two nanofiber membranes were taken and subjected to glutaraldehyde vapor crosslinking treatment to obtain a first crosslinked nanofiber material, and subjected to thermal crosslinking treatment to obtain a second crosslinked nanofiber material. The first and second nanofiber materials were homogeneously dispersed in a lyophilization solvent at a mass ratio of 1:0.2 to 5 to obtain a nanofiber dispersion. The nanofiber dispersion was freeze-dried and vacuum-dried to obtain a nanofiber scaffold. The lyophilization solvent in the dispersion of the first nanofiber material always contained tert-butanol.
[0008] In the above process, the first nanofiber material cross-linked by glutaraldehyde vapor and the second nanofiber material cross-linked by heat are homogeneously dispersed in a lyophilization solvent to form a nanofiber dispersion. The nanofiber dispersion is then freeze-dried and vacuum-dried to obtain a nanofiber scaffold with a three-dimensional structure. The synergistic effect of the first nanofiber material cross-linked by glutaraldehyde vapor and the second nanofiber material cross-linked by heat improves the structural stability and appearance quality of the nanofiber scaffold. Furthermore, since the first nanofiber material cross-linked by glutaraldehyde vapor is consistently dispersed in a lyophilization solvent containing tert-butanol, the mixing uniformity of the nanofiber dispersion is improved, thus enhancing the pore structure and structural stability of the nanofiber scaffold.
[0009] In conjunction with the first aspect, in an optional embodiment of this application, the lyophilization solvent in the nanofiber dispersion further includes water.
[0010] In the above process, the freeze-drying solvent in the nanofiber dispersion contains water, which helps to regulate the pore structure of the nanofiber scaffold and improves the environmental friendliness of the nanofiber scaffold preparation process, making it more suitable for biomedical materials.
[0011] In conjunction with the first aspect, in an optional embodiment of this application, the first nanofiber material and the second nanofiber material are homogeneously dispersed in a lyophilization solvent, comprising:
[0012] The first nanofiber material was homogeneously dispersed in a lyophilization solvent containing tert-butanol to obtain a pre-dispersion; the second nanofiber material was homogeneously dispersed in the pre-dispersion to form a nanofiber dispersion.
[0013] Optionally, the total mass ratio of the first nanofiber material and the second nanofiber material to the freeze-drying solvent is 1:50 to 100.
[0014] In the above process, the first nanofiber is first homogeneously dispersed in a lyophilization solvent containing tert-butanol to ensure uniform dispersion of the first nanofiber material, thus obtaining a uniformly dispersed pre-dispersion. Then, the second nanofiber material is homogeneously dispersed in the pre-dispersion, which improves the dispersion uniformity of the obtained nanofiber dispersion, enhances the pore structure and appearance quality of the nanofiber scaffold, and improves structural stability.
[0015] In conjunction with the first aspect, in an optional embodiment of this application, the first nanofiber material is homogeneously dispersed in an aqueous solution of tert-butanol to obtain a pre-dispersion.
[0016] Optionally, in the aqueous solution of tert-butanol, the mass ratio of tert-butanol to water is 1 to 5:1.
[0017] In the above process, the first nanofiber material after glutaraldehyde vapor crosslinking is homogeneously dispersed in a tert-butanol aqueous solution. Even if the tert-butanol aqueous solution contains water, the first nanofiber material can be evenly dispersed. Then, the second nanofiber material obtained by thermal crosslinking is dispersed in a pre-dispersion liquid to obtain a uniformly dispersed nanofiber dispersion.
[0018] In conjunction with the first aspect, in an optional embodiment of this application, the first nanofiber material is homogeneously dispersed in tert-butanol to obtain a pre-dispersion; water and the second nanofiber material are added to the pre-dispersion and homogeneously dispersed to form a nanofiber dispersion.
[0019] Optionally, the mass ratio of tert-butanol to water is 1 to 5:1.
[0020] In the above process, the first nanofiber material, after being cross-linked by glutaraldehyde vapor, is first homogeneously dispersed in tert-butanol. Tert-butanol does not contain water, which further improves the dispersion uniformity of the pre-dispersion solution. Then, the second nanofiber material, after being thermally cross-linked, is added to the pre-dispersion solution along with water for homogeneous dispersion. The lyophilization solvent in the nanofiber dispersion contains water, which improves the pore structure of the nanofiber scaffold, thereby enhancing the structural stability and appearance quality of the nanofiber scaffold.
[0021] In conjunction with the first aspect, in optional embodiments of this application, the crosslinking temperature of the glutaraldehyde vapor crosslinking treatment is 50-80°C, and the crosslinking time is 10-18 h. And / or, the crosslinking temperature of the thermal crosslinking treatment is 120-180°C, and the crosslinking time is 1-4 h; optionally, the thermal crosslinking time is 2 h.
[0022] In the above process, a portion of the nanofiber membrane is subjected to glutaraldehyde vapor crosslinking at a temperature of 50-80℃ for 10-18 hours, and another portion of the nanofiber membrane is subjected to thermal crosslinking at a temperature of 120-180℃ for 2 hours. This can improve the stability of the nanofiber material, thereby improving the appearance quality and structural stability of the nanofiber scaffold.
[0023] In conjunction with the first aspect, in an optional embodiment of this application, the method for preparing the nanofiber membrane includes:
[0024] Nanofiber membranes are obtained by electrospinning a spinning solution containing polymer materials.
[0025] Optionally, the polymer material is selected from hydrophilic polymer materials.
[0026] Optionally, the polymer material is selected from polyvinyl alcohol.
[0027] Optionally, the spinning solution may also contain surfactants.
[0028] Optionally, the surfactant is selected from sodium dodecyl sulfate and / or polydimethylsiloxane.
[0029] Optional parameters for electrospinning include: spinning voltage of 15-45kV, spinning solution flow rate of 0.2-1ml / h, receiving roller speed of 600-1000r / min, temperature of 20-30℃, and humidity of 30%-60%.
[0030] In the above process, since the nanofiber membrane is first cross-linked with glutaraldehyde vapor and then thermally cross-linked before the lyophilization solvent dispersion and freeze-drying, even nanofiber membranes containing hydrophilic polymer materials can be dispersed in a water-containing lyophilization solvent, and a nanofiber scaffold with a stable three-dimensional structure can be obtained after subsequent freeze-drying.
[0031] In conjunction with the first aspect, in an optional embodiment of this application, the vacuum drying temperature is 100-150°C and the time is 10-18 hours.
[0032] In conjunction with the first aspect, in an optional embodiment of this application, the freeze-drying temperature is -50 to 30°C and the time is 18-35 hours.
[0033] In the above process, since the nanofiber membrane was first cross-linked with glutaraldehyde vapor and thermally before dispersing the nanofiber material in the freeze-drying solvent and freeze-drying, the freeze-dried nanofiber scaffold has good structural stability. When the freeze-dried nanofiber scaffold is transferred to a vacuum drying oven for vacuum drying, the structure of the nanofiber scaffold is not easily damaged, and the nanofiber scaffold is not easily deformed after vacuum drying.
[0034] In a second aspect, an example of this application provides a nanofiber scaffold prepared according to the preparation method provided in the first aspect.
[0035] In the above-mentioned process, the nanofiber scaffold prepared according to the preparation method provided in the embodiments of this application has good three-dimensional structure, structural stability and appearance quality. Attached Figure Description
[0036] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.
[0037] Figure 1 A process flow diagram of the fabrication process of the nanofiber scaffold provided as an example in this application;
[0038] Figure 2 This is a physical image of the nanofiber scaffold provided in Embodiment 1 of this application;
[0039] Figure 3 This is a physical image of the nanofiber scaffold provided in Embodiment 2 of this application;
[0040] Figure 4 This is a physical image of the nanofiber scaffold provided in Embodiment 3 of this application;
[0041] Figure 5 This is a physical image of the nanofiber scaffold provided in Embodiment 4 of this application;
[0042] Figure 6 This is a physical image of the nanofiber scaffold provided in Embodiment 5 of this application;
[0043] Figure 7 A physical image of the nanofiber scaffold provided in Comparative Example 1 of this application;
[0044] Figure 8 A physical image of the nanofiber scaffold provided in Comparative Example 2 of this application;
[0045] Figure 9 A physical image of the nanofiber scaffold provided in Comparative Example 3 of this application;
[0046] Figure 10 This is a physical image of the nanofiber scaffold provided in Comparative Example 4 of this application. Detailed Implementation
[0047] The embodiments of this application will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are for illustrative purposes only and should not be considered as limiting the scope of this application. Unless otherwise specified in the examples, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.
[0048] In order to prepare a nanofiber scaffold with stable structure and good appearance, the inventors tried to homogenize and pulverize the electrospun nanofiber membrane, and then freeze-dry and vacuum-dry it.
[0049] For example, electrospun nanofiber membranes are prepared by electrospinning a spinning solution containing polymer materials. The electrospun nanofiber membrane is homogeneously dispersed in a lyophilization solvent to form a short fiber dispersion, which is then freeze-dried and vacuum-dried. The lyophilization solvent is tert-butanol, and the polymer material is a hydrophilic polymer. However, the structural stability of the prepared nanofiber scaffold needs further improvement.
[0050] To further improve the structural stability and appearance quality of the nanofiber scaffold, the inventors attempted to cross-link the freeze-dried nanofiber scaffold, followed by vacuum drying. For example, the cross-linking process involved using a 0.5% glutaraldehyde alcohol solution.
[0051] However, the structural stability of the prepared nanofiber scaffolds still needs to be improved. Furthermore, the inventors discovered that transferring the freeze-dried nanofiber scaffolds to a 0.5% glutaraldehyde alcohol solution for crosslinking, followed by vacuum drying, easily leads to deformation of the nanofiber scaffolds during the transfer process. Vacuum drying also causes deformation, resulting in nanofiber scaffolds with uneven appearance.
[0052] Furthermore, the inventors discovered that adding a certain amount of deionized water to the freeze-drying solvent helps to regulate the pore structure of the nanofiber scaffold and improve its environmental friendliness, making it suitable for biomedical materials. However, it is impossible to homogeneously disperse nanofiber membranes containing hydrophilic polymers in a freeze-drying solvent containing deionized water.
[0053] Therefore, in order to further improve the structural stability and appearance quality of nanofiber scaffolds and to address the compatibility issues between nanofiber membranes and lyophilization solvents, this application provides a method for preparing nanofiber scaffolds. To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.
[0054] Please see Figure 1 The method for preparing the nanofiber scaffold provided in this application includes:
[0055] S1. Obtain nanofiber membrane.
[0056] S2. Take two nanofiber membranes and perform glutaraldehyde vapor crosslinking treatment to obtain the first crosslinked nanofiber material, and perform thermal crosslinking treatment to obtain the second crosslinked nanofiber material.
[0057] S3. The first nanofiber material and the second nanofiber material are homogeneously dispersed in a lyophilization solvent at a mass ratio of 1:0.2 to 5 to obtain a nanofiber dispersion; wherein the lyophilization solvent in the dispersion of the first nanofiber material always contains tert-butanol.
[0058] S4. Freeze-dry the nanofiber dispersion and then vacuum-dry it to obtain a nanofiber scaffold.
[0059] In the preparation method provided in this application, the nanofiber membrane is cross-linked before being homogeneously dispersed in the lyophilization solvent. This cross-linking process makes the nanofiber material more stable, so even if the nanofiber material contains hydrophilic polymers, it can still be dispersed in a lyophilization solvent containing deionized water and tert-butanol. Through the preparation method provided in this application, the nanofiber membrane containing hydrophilic polymers can be uniformly dispersed in lyophilization solvents containing or without deionized water, thus improving the compatibility between the nanofiber membrane and the lyophilization solvent.
[0060] Furthermore, before dispersing in the freeze-drying solvent, when performing cross-linking treatment on the nanofiber membrane, a portion of the nanofiber membrane is first subjected to glutaraldehyde vapor cross-linking treatment to obtain the first cross-linked nanofiber material, and another portion of the nanofiber membrane is subjected to thermal cross-linking treatment to obtain the second cross-linked nanofiber material. The first and second nanofiber materials are homogeneously dispersed in the freeze-drying solvent at a mass ratio of 1:0.2 to 5 to obtain a nanofiber dispersion. Then, the nanofiber dispersion is freeze-dried and vacuum-dried. By utilizing the synergy between the first nanofiber material cross-linked by glutaraldehyde vapor and the second nanofiber material cross-linked by thermal treatment, the structural stability and appearance quality of the nanofiber scaffold obtained by subsequent drying can be further improved.
[0061] In addition, the nanofiber membrane is pre-crosslinked before being dispersed in the freeze-drying solvent, and then directly vacuum-dried after freeze-drying. This eliminates the need for multiple transfers before vacuum drying, reducing the likelihood of deformation of the nanofiber scaffold and improving its appearance quality.
[0062] In step S1, this application does not limit how the nanofiber membrane is obtained. In some possible embodiments, the nanofiber membrane can be an electrospun nanofiber membrane.
[0063] Furthermore, the preparation methods of electrospun nanofiber membranes include:
[0064] Nanofiber membranes are obtained by electrospinning a spinning solution containing polymer materials.
[0065] Among these methods, polymeric materials can undergo a cross-linking reaction with glutaraldehyde vapor. After subsequently subjecting an electrospun nanofiber membrane containing polymeric materials to glutaraldehyde vapor cross-linking treatment, a first cross-linked nanofiber material can be obtained. Similarly, polymeric materials can undergo a cross-linking reaction during thermal cross-linking to obtain a second cross-linked nanofiber material.
[0066] For example, during glutaraldehyde vapor crosslinking, functional groups in polymer materials, such as active hydrogen-containing functional groups, amine functional groups, or double bonds, can undergo crosslinking reactions to form crosslinked structures.
[0067] For example, during thermal crosslinking, under certain temperature, appropriate pressure and time conditions, free radicals in polymer materials can undergo crosslinking reactions to form crosslinked structures.
[0068] The polymer material is a hydrophilic polymer material.
[0069] For example, the polymer material can be selected from hydrophilic polymer materials, such as polyvinyl alcohol (PVA), gelatin, etc.
[0070] Furthermore, surfactants can be added to the spinning solution to improve the spinning process and enhance the spinning quality.
[0071] For example, the surfactant may be selected from sodium dodecyl sulfate-polydimethylsiloxane (SDS-PDMS).
[0072] For example, the spinning solution comprises a 5%-15% by mass aqueous solution of PVA. 0.03%-0.1% SDS-PDMS may also be added to the PVA aqueous solution.
[0073] Furthermore, the preparation method of the spinning solution includes: according to the mass ratio, placing the weighed PVA powder in deionized water, adding a magnetic stir bar, heating and stirring at 60-95℃ for 2-6 hours until clear and transparent to obtain a PVA aqueous solution; adding the weighed surfactant SDS-PDMS to the PVA aqueous solution, stirring at room temperature for 2-4 hours until uniform, letting it stand at room temperature for 4-8 hours to remove bubbles or using an ultrasonic device for 10 minutes to remove bubbles to obtain the final PVA spinning solution.
[0074] Furthermore, the parameters for electrospinning include: spinning voltage of 15-45kV, spinning solution flow rate of 0.2-1ml / h, receiving roller speed of 600-1000r / min, temperature of 20-30℃, and humidity of 30%-60%.
[0075] In step S2, the temperature for glutaraldehyde vapor crosslinking treatment can be 50-80℃, and the crosslinking time can be 10-18h.
[0076] For example, the temperature of the glutaraldehyde vapor crosslinking treatment can be one of 50°C, 60°C, 70°C or 80°C or any combination thereof.
[0077] For example, the glutaraldehyde vapor crosslinking treatment time can be one of 10h, 11h, 12h, 13h, 14h, 15h, 16h, 17h or 18h or any combination thereof.
[0078] In step S2, the temperature for thermal crosslinking treatment can be 120-180℃, and the crosslinking time can be 1-4h.
[0079] Furthermore, the thermal cross-linking time is 2 hours.
[0080] For example, the temperature of the thermal crosslinking treatment can be one of 120°C, 130°C, 140°C, 150°C, 160°C, 170°C or 180°C or any combination thereof.
[0081] For example, the thermal crosslinking treatment time can be one of 1h, 2h, 3h or 4h or any combination thereof.
[0082] Furthermore, in some possible embodiments, the nanofiber membrane can be cut into pieces before undergoing glutaraldehyde vapor crosslinking treatment and thermal crosslinking treatment respectively.
[0083] Alternatively, in some other possible embodiments, the nanofiber membrane may be cross-linked before being shredded.
[0084] In step S3, the first nanofiber material and the second nanofiber material are homogeneously dispersed in a lyophilization solvent at a mass ratio of 1:0.2 to 5 to obtain a nanofiber dispersion. For example, the mass ratio of the first nanofiber material to the second nanofiber material can be one of 1:0.2, 1:0.5, 1:1, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, or 1:5, or any range between two of these ratios.
[0085] In step S3, in some possible embodiments, the first nanofiber material can be homogeneously dispersed in a lyophilization solvent containing tert-butanol to obtain a pre-dispersion; the second nanofiber material can be homogeneously dispersed in the pre-dispersion to form a nanofiber dispersion.
[0086] Furthermore, the ratio of the total mass of the first nanofiber material and the second nanofiber material to the mass of the freeze-drying solvent is 1:50 to 100.
[0087] For example, 0.25 g of the first nanofiber material and 0.05 g of the second nanofiber material are homogeneously dispersed in 20 g of lyophilization solvent.
[0088] For example, 0.25 g of the first nanofiber material and 0.05 g of the second nanofiber material are homogeneously dispersed in 30 g of lyophilization solvent.
[0089] Furthermore, the lyophilization solvent contains tert-butanol and water, with a mass ratio of tert-butanol to water of 1 to 5:1.
[0090] For example, the lyophilization solvent contains 20g of tert-butanol and 10g of deionized water.
[0091] In step S3, the freeze-drying solvent in the dispersion of the first nanofiber material always contains tert-butanol, meaning that the first nanofiber material after glutaraldehyde vapor crosslinking cannot be directly dispersed in a freeze-drying solvent that does not contain tert-butanol.
[0092] For example, when the lyophilization solvent in the nanofiber dispersion contains tert-butanol and water, water and tert-butanol can be mixed first to form a tert-butanol aqueous solution. The first nanofiber material can be homogeneously dispersed in the tert-butanol aqueous solution, and then the second nanofiber material can be homogeneously dispersed in the pre-dispersion solution. Alternatively, the first nanofiber material can be homogeneously dispersed in tert-butanol first, and then the second nanofiber material and water can be added together to the pre-dispersion solution and homogenized to form a nanofiber dispersion.
[0093] For example, 0.25g of the first nanofiber material can be homogeneously dispersed in 30g of tert-butanol aqueous solution to obtain a pre-dispersion; the tert-butanol aqueous solution contains 20g of tert-butanol and 10g of deionized water. 0.05g of the second nanofiber material is then homogeneously dispersed in the pre-dispersion to form a nanofiber dispersion.
[0094] Alternatively, in another possible embodiment, 0.25g of the first nanofiber material can be homogeneously dispersed in 20g of tert-butanol to obtain a pre-dispersion; 10g of deionized water and 0.05g of the second nanofiber material can be added to the pre-dispersion and homogeneously dispersed to form a nanofiber dispersion.
[0095] In step S4, the temperature for freeze-drying the nanofiber dispersion can be -50 to 30°C, and the time can be 18 to 35 hours.
[0096] For example, the freeze-drying time can be one of 18h, 20h, 25h, 30h or 35h or any combination thereof.
[0097] Furthermore, in order to facilitate obtaining nanofiber scaffolds of specific shapes and sizes, the nanofiber dispersion can be placed in a corresponding mold for freeze drying.
[0098] In step S4, the vacuum drying temperature can be 100-150℃ and the time can be 10-18h.
[0099] For example, the temperature of vacuum drying can be one or more of 100°C, 110°C, 120°C, 130°C, 140°C or 150°C or any two of them; the time of vacuum drying can be one or more of 10h, 12h, 15h, 16h or 18h or any two of them.
[0100] Furthermore, this application provides a nanofiber scaffold prepared according to the above-described method. The nanofiber scaffold provided in this application exhibits good structural stability and appearance quality.
[0101] The nanofiber scaffold and its preparation method of this application are further described in detail below with reference to the embodiments.
[0102] Example 1
[0103] Example 1 provides a nanofiber scaffold, prepared by the following method:
[0104] Step 1: Weigh 4.5g of PVA powder using a precision electronic balance and dissolve it in 45mL of deionized water. Add a magnetic stir bar and stir in a 95℃ water bath until clear and transparent to obtain a PVA aqueous solution.
[0105] Step 2: Weigh 0.015g of SDS and 0.015g of PDMS using a precision electronic balance, add them to the PVA aqueous solution obtained in Step 1, stir at room temperature for 2-4 hours until homogeneous, let stand at room temperature for 4-8 hours to remove bubbles or use an ultrasonic device for 10 minutes to remove bubbles, and obtain the final PVA spinning solution.
[0106] Step 3: Take the above PVA spinning solution into a syringe, fix the syringe to the injection pump of the electrospinning machine, attach the needle connected to the positive terminal of the high-voltage power supply, and connect the receiving roller to the negative terminal of the high-voltage power supply. Set the spinning parameters: spinning voltage is 22kV, spinning solution flow rate is 0.5ml / h, receiving roller speed is 800r / min, temperature is 21℃, and humidity is 50%.
[0107] Step 4: Dry the nanofiber membrane prepared by spinning above at room temperature for 12 hours and divide it into two portions. Crosslink one portion of the nanofiber membrane with glutaraldehyde vapor for 18 hours at a crosslinking temperature of 60°C to obtain the first nanofiber material. Place the other portion of the nanofiber membrane at 160°C for thermal crosslinking for 2 hours to obtain the second nanofiber material.
[0108] Step 5: Cut the first and second nanofiber materials obtained in Step 4 into small pieces (1×1cm). Weigh 0.05g of the second nanofiber material and 0.25g of the first nanofiber material using a precision balance, mix them, and add them to a homogenizer containing 20g of tert-butanol to break them into a uniform short nanofiber dispersion. Then add 10g of deionized water to the homogenizer containing the short nanofiber dispersion, stir and break it up to obtain a uniformly dispersed nanofiber dispersion.
[0109] Step 6: Weigh 4.5g of the nanofiber dispersion obtained in Step 5 using a precision balance, add it to a twelve-well culture plate, and freeze-dry for 24 hours to form a nanofiber scaffold.
[0110] Step 7: Place the nanofiber scaffold from Step 6 in a vacuum drying oven and dry it for 12 hours at a temperature of 120°C to obtain the nanofiber scaffold.
[0111] Observing the nanofiber scaffold provided in Example 1, the nanofiber scaffold has a flat appearance and a relatively compact and stable structure. A physical image of the nanofiber scaffold provided in Example 1 is shown below. Figure 2 As shown.
[0112] Example 2
[0113] Example 2 provides a nanofiber scaffold, which differs from Example 1 in that:
[0114] In step 3, the spinning parameters are as follows: spinning voltage is 24kV, spinning solution flow rate is 0.6ml / h, receiving roller speed is 800r / min, temperature is 23℃, and humidity is 55%.
[0115] In step 5, the first and second nanofiber materials obtained in step 4 are cut into small pieces (1×1cm). Using a precision balance, 0.05g of the second nanofiber material and 0.25g of the first nanofiber material are weighed, mixed, and added to a homogenizer containing 30g of tert-butanol aqueous solution to break them into a uniform short nanofiber dispersion. The tert-butanol aqueous solution contains 20g of tert-butanol and 10g of deionized water.
[0116] Observing the nanofiber scaffold provided in Example 2, the nanofiber scaffold has a flat appearance and a relatively compact and stable structure. A physical image of the nanofiber scaffold provided in Example 2 is shown below. Figure 3 As shown.
[0117] Example 3
[0118] Example 3 provides a nanofiber scaffold, which differs from Example 2 in that:
[0119] In step 3, the spinning parameters are as follows: spinning voltage is 23kV, spinning solution flow rate is 0.6ml / h, receiving roller speed is 800r / min, temperature is 22℃, and humidity is 48%.
[0120] In step 5, the first and second nanofiber materials obtained in step 4 are cut into small pieces (1×1cm). 0.05g of the second nanofiber material and 0.25g of the first nanofiber material are weighed using a precision balance. The first nanofiber material is first added to a homogenizer containing 30g of tert-butanol aqueous solution and broken into a uniform short fiber pre-dispersion. The tert-butanol aqueous solution contains 20g of tert-butanol and 10g of deionized water. Then, the second nanofiber material is added to the homogenizer containing the pre-dispersion and stirred together to obtain a nanofiber dispersion.
[0121] Observing the nanofiber scaffold provided in Example 3, the nanofiber scaffold has a flat appearance and a relatively compact and stable structure. A physical image of the nanofiber scaffold provided in Example 3 is shown below. Figure 4 As shown.
[0122] Example 4
[0123] Example 4 provides a nanofiber scaffold, which differs from Example 2 in that:
[0124] In step 3, the spinning parameters are as follows: spinning voltage is 23kV, spinning solution flow rate is 0.6ml / h, receiving roller speed is 800r / min, temperature is 22℃, and humidity is 48%.
[0125] In step 5, the first and second nanofiber materials obtained in step 4 are cut into small pieces (1×1cm). 0.05g of the second nanofiber material and 0.25g of the first nanofiber material are weighed using a precision balance. The first nanofiber material is first added to a homogenizer containing 20g of tert-butanol and broken into a uniform short fiber pre-dispersion. Then, the second nanofiber material and 10g of deionized water are added to the homogenizer containing the pre-dispersion and stirred together to obtain a nanofiber dispersion.
[0126] Observing the nanofiber scaffold provided in Example 4, the nanofiber scaffold has a flat appearance and a relatively compact and stable structure. A physical image of the nanofiber scaffold provided in Example 4 is shown below. Figure 5 As shown.
[0127] Example 5
[0128] Example 5 provides a nanofiber scaffold, which differs from Example 1 in that:
[0129] In step 3, the spinning voltage is 22kV, the spinning solution flow rate is 0.5ml / h, the receiving roller speed is 800r / min, the temperature is 21℃, and the humidity is 50%.
[0130] In step 5, the first and second nanofiber materials obtained in step 4 are cut into small pieces (1×1cm). 0.05g of the second nanofiber material and 0.25g of the first nanofiber material are weighed using a precision balance, mixed, and added to a homogenizer containing 30g of tert-butanol to break them into a uniform nanofiber dispersion.
[0131] Observing the nanofiber scaffold provided in Example 5, the nanofibers have a slightly uneven appearance but a relatively compact and stable structure. Compared to the nanofiber scaffold provided in Example 5, the nanofiber scaffold provided in Example 1 has a more uniform and flat appearance. A physical image of the nanofiber scaffold provided in Example 5 is shown below. Figure 6 As shown.
[0132] Comparative Example 1
[0133] A comparative example provides a nanofiber scaffold, which differs from Example 1 in that:
[0134] In step 3, the spinning parameters are as follows: spinning voltage is 22kV, spinning solution flow rate is 0.5ml / h, receiving roller speed is 800r / min, temperature is 21℃, and humidity is 50%.
[0135] Step 4: Cut the nanofiber membrane obtained in Step 3 into small pieces and add it to tert-butanol. Homogenize and pulverize the mixture to obtain a uniformly dispersed nanofiber dispersion. Pour the dispersion into a 12-well culture plate and freeze-dry it.
[0136] Step 5: Add 0.5% glutaraldehyde alcohol solution to the nanofiber scaffold obtained in Step 4 for cross-linking and molding.
[0137] Step 6: Place the cross-linked nanofiber scaffold formed in Step 5 into a vacuum drying oven to dry and shape it, thus obtaining the final nanofiber scaffold.
[0138] Upon observation of the nanofiber scaffold provided in Comparative Example 1, the nanofiber scaffold exhibits deformation, an uneven surface, and a non-uniform structure. A photograph of the actual appearance of the nanofiber scaffold provided in Comparative Example 1 is shown below. Figure 7 As shown.
[0139] Comparative Example 2
[0140] Comparative Example 2 provides a nanofiber scaffold, which differs from Example 4 in that:
[0141] In step 3, the spinning parameters are as follows: spinning voltage is 23kV, spinning solution flow rate is 0.6ml / h, receiving roller speed is 800r / min, temperature is 22℃, and humidity is 48%.
[0142] In step 5, the first and second nanofiber materials obtained in step 4 are cut into small pieces (1×1cm). 0.05g of the second nanofiber material and 0.25g of the first nanofiber material are weighed using a precision balance. The first nanofiber material is first added to a homogenizer containing 10g of deionized water and broken into a uniform short fiber pre-dispersion. Then, the second nanofiber material and 20g of tert-butanol are added to the homogenizer containing the pre-dispersion and stirred together to obtain a nanofiber dispersion.
[0143] Observing the nanofiber scaffold provided in Comparative Example 2, the nanofibers appear deformed, rough, and have a loose structure. A physical image of the nanofiber scaffold provided in Comparative Example 2 is shown below. Figure 8 As shown.
[0144] Comparative Example 3
[0145] Comparative Example 3 provides a nanofiber scaffold, which differs from Example 1 in that:
[0146] In step 3, the spinning parameters are as follows: spinning voltage is 22kV, spinning solution flow rate is 0.5ml / h, receiving roller speed is 800r / min, temperature is 21℃, and humidity is 50%.
[0147] In step 4, the nanofiber membrane prepared by the above spinning process is dried at room temperature for 12 hours and divided into two portions. The nanofiber membrane is then subjected to glutaraldehyde vapor crosslinking for 18 hours at a crosslinking temperature of 60°C to obtain the first nanofiber material.
[0148] In step 5, the first nanofiber material obtained in step 4 is cut into pieces (1×1cm). 0.05g + 0.25g of the first nanofiber material is weighed using a precision balance and added to a homogenizer containing 20g of tert-butanol to break it into a uniform short nanofiber dispersion. Then, 10g of deionized water is added to the homogenizer containing the short nanofiber dispersion and stirred together to break it up, resulting in a uniformly dispersed nanofiber dispersion.
[0149] Upon observation of the nanofiber scaffold provided in Comparative Example 3, the nanofiber scaffold has a rough and uneven appearance. A photograph of the actual appearance of the nanofiber scaffold provided in Comparative Example 3 is shown below. Figure 9 As shown.
[0150] Comparative Example 4
[0151] Comparative Example 4 provides a nanofiber scaffold, which differs from Example 1 in that:
[0152] In step 3, the spinning parameters are as follows: spinning voltage is 22kV, spinning solution flow rate is 0.5ml / h, receiving roller speed is 800r / min, temperature is 21℃, and humidity is 50%.
[0153] In step 4, the nanofiber membrane prepared by spinning is dried at room temperature for 12 hours and divided into two portions. The nanofiber membrane is then subjected to thermal crosslinking at 160°C for 2 hours to obtain the second nanofiber material.
[0154] In step 5, the second nanofiber material obtained in step 4 is cut into pieces (1×1cm). 0.05g + 0.25g of the second nanofiber material is weighed using a precision balance and added to a homogenizer containing 20g of tert-butanol to break it into a uniform short nanofiber dispersion. Then, 10g of deionized water is added to the homogenizer containing the short nanofiber dispersion and stirred together to break it up, resulting in a uniformly dispersed nanofiber dispersion.
[0155] Observation of the nanofiber scaffold provided in Comparative Example 4 shows that the nanofiber scaffold partially collapsed, easily shed fibers, and required a longer freeze-drying time. A physical image of the nanofiber scaffold provided in Comparative Example 4 is shown below. Figure 10 As shown.
[0156] Test case
[0157] The compressive strength of the nanofiber scaffolds provided in Examples 1-5 and Comparative Examples 1-4 was tested. The test methods included:
[0158] The nanofiber scaffold specimen was compressed to 50% of its original thickness using an electronic spring tensile and compressive testing machine. The stress at 50% deformation was recorded to obtain the compressive strength of the nanofiber scaffold specimen. The test structure is shown in Table 1.
[0159] Table 1
[0160]
[0161] In comparative tests, the nanofiber scaffolds either exhibited rough appearance and deformation, or had a very loose structure lacking three-dimensionality, rendering the measured compressive strength meaningless. In contrast, the nanofiber scaffolds provided in Examples 1-4 demonstrated stable structures and high compressive strength. This indicates that by homogenizing two nanofiber materials obtained through glutaraldehyde vapor crosslinking and thermal crosslinking methods in a lyophilization solvent, and adjusting the order of solvent addition during the homogenization process, a nanofiber scaffold with a smooth appearance and stable structure can be obtained.
[0162] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. A method for preparing a nanofiber scaffold, characterized in that, include: Two nanofiber membranes were subjected to glutaraldehyde vapor crosslinking treatment to obtain the first crosslinked nanofiber material, and thermal crosslinking treatment to obtain the second crosslinked nanofiber material. The first nanofiber material and the second nanofiber material are homogeneously dispersed in a freeze-drying solvent at a mass ratio of 1:0.2 to 5 to obtain a nanofiber dispersion; the nanofiber dispersion is freeze-dried and vacuum-dried to obtain the nanofiber scaffold; wherein the freeze-drying solvent in the dispersion of the first nanofiber material always contains tert-butanol.
2. The preparation method according to claim 1, characterized in that, The freeze-drying solvent in the nanofiber dispersion also includes water.
3. The preparation method according to claim 1, characterized in that, The first nanofiber material and the second nanofiber material are homogeneously dispersed in a lyophilization solvent, comprising: The first nanofiber material is homogeneously dispersed in a lyophilization solvent containing tert-butanol to obtain a pre-dispersion; the second nanofiber material is homogeneously dispersed in the pre-dispersion to form the nanofiber dispersion. Optionally, the ratio of the total mass of the first nanofiber material and the second nanofiber material to the mass of the freeze-drying solvent is 1:50 to 100.
4. The preparation method according to claim 3, characterized in that, The first nanofiber material was homogeneously dispersed in an aqueous solution of tert-butanol to obtain the pre-dispersion. Optionally, in the aqueous solution of tert-butanol, the mass ratio of tert-butanol to water is 1 to 5:
1.
5. The preparation method according to claim 3, characterized in that, The first nanofiber material is homogeneously dispersed in tert-butanol to obtain the pre-dispersion liquid; water and the second nanofiber material are added to the pre-dispersion liquid and homogeneously dispersed to form the nanofiber dispersion liquid; Optionally, the mass ratio of tert-butanol to water is 1 to 5:
1.
6. The preparation method according to claim 1, characterized in that, The crosslinking temperature of the glutaraldehyde vapor crosslinking treatment is 50-80℃, and the crosslinking time is 10-18h; And / or, the crosslinking temperature of the thermal crosslinking treatment is 120-180℃, and the crosslinking time is 1-4h; optionally, the thermal crosslinking time is 2h.
7. The preparation method according to claim 1, characterized in that, The method for preparing the nanofiber membrane includes: The nanofiber membrane is obtained by electrospinning a spinning solution containing polymer materials. Optionally, the polymer material is selected from hydrophilic polymer materials; Optionally, the polymer material is selected from polyvinyl alcohol; Optionally, the spinning solution may also contain a surfactant; Optionally, the surfactant is selected from sodium dodecyl sulfate and / or polydimethylsiloxane; Optionally, the parameters of the electrospinning include: spinning voltage of 15-45kV, spinning solution flow rate of 0.2-1ml / h, receiving roller speed of 600-1000r / min, temperature of 20-30℃, and humidity of 30%-60%.
8. The preparation method according to claim 1, characterized in that, The vacuum drying temperature is 100-150℃, and the time is 10-18h.
9. The preparation method according to claim 1, characterized in that, The freeze-drying temperature is -50 to 30°C, and the time is 18 to 35 hours.
10. A nanofiber scaffold prepared by the preparation method according to any one of claims 1-9.