CN118059241A - Piezoelectric composite membrane for wound healing and preparation method and application thereof - Google Patents
Piezoelectric composite membrane for wound healing and preparation method and application thereof Download PDFInfo
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- A61K47/00—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
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- A61K9/00—Medicinal preparations characterised by special physical form
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- A—HUMAN NECESSITIES
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- A61P17/02—Drugs for dermatological disorders for treating wounds, ulcers, burns, scars, keloids, or the like
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Abstract
The invention is suitable for the technical field of membrane separation materials, and provides a piezoelectric composite membrane for wound healing, and a preparation method and application thereof. The DA/PVDF piezoelectric composite membrane activated by utilizing the LIPUS can promote wound healing. Under ultrasonic stimulation, the membrane can generate stable local electric stimulation; the membrane is more beneficial to cell adhesion by modifying dopamine, and is beneficial to forming a continuous cell layer on the surface of the membrane by cells; under ultrasonic stimulation, the cell activity and mobility of the membrane are obviously increased, and particularly under high-power ultrasonic treatment, the membrane shows obvious enhancement effect; in animal experiments, the membrane remarkably improves the healing effect of wound surfaces under ultrasonic stimulation, promotes the deposition of type I collagen at wound positions, and reflects the structural remodeling advantage of the membrane in the wound healing process; and the membrane has good in vivo biosafety under ultrasonic stimulation.
Description
Technical Field
The invention belongs to the technical field of membrane separation materials, and particularly relates to a piezoelectric composite membrane for wound healing, and a preparation method, application and application thereof.
Background
The skin is the largest organ of the human body and is extremely vulnerable to external threats. Skin wound healing includes hemostasis and inflammation, new tissue formation, and tissue remodeling. Different forms of electrical stimulation can actively regulate endogenous cellular behavior, promote wound healing by enhancing proliferation and differentiation of glial cells, fibroblasts, and increasing formation of adenosine triphosphate and proteins. And clinical electrical stimulation equipment can be costly to the patient. Thus, there is a need for a new method of non-invasive, wireless, active control of cellular behavior to regulate skin cell regeneration and to allow it to participate in wound healing.
PVDF has excellent piezoelectric properties, biocompatibility, and flexibility due to low young's modulus. PVDF is a piezoelectric polymer having five crystalline conformations of alpha-beta. The beta phase of PVDF adopts an all-trans conformation, so that the dipole moment is the largest and the piezoelectric capacity is the highest. However, during mechanical stretching or temperature fluctuations, PVDF with a higher beta phase content may partially depolarize due to thermal motion, returning to the thermodynamically stable non-piezoelectric phase. And if the wound is in a region where deformation is difficult, the electrical stimulation generated by the PVDF film will be greatly reduced and thus will be greatly limited in wound healing applications.
Ultrasonic energy is delivered to the wound site in the form of mechanical waves that mechanically stimulate and deform the piezoelectric material, which in turn creates an electrical microenvironment in the vicinity of the wound, similar to an endogenous electric field. Low Intensity Pulsed Ultrasound (LIPUS) is a special type of ultrasound that is safer than other types of ultrasound, with minimal thermal effects from LIPUS. The LIPUS equipment is simple and convenient to operate, and the intensity of the LIPUS equipment is far lower than that of ultrasonic waves generated by most traditional clinical equipment, so that the LIPUS equipment is possible to be a home rehabilitation equipment. At the same time, LIPUS also has the advantage of being non-invasive and penetrating.
Dopamine (DA) is a derivative of tyrosine, which is of great interest because it contains functional groups such as catechol groups and hydroxyl groups, which can combine with a variety of molecules in different scaffold materials to form functional interfaces. The strong adhesion, good biocompatibility and ability to scavenge ROS of DA are beneficial for wound closure and tissue engineering. Compared with other piezoelectric fillers (such as organic modified nanoclay, metal nanoparticles, functionalized multi-walled carbon nanotubes, graphene and derivatives thereof), the piezoelectric filler has extremely excellent biocompatibility. Therefore, a DA/PVDF piezoelectric composite membrane activated by LIPUS, a preparation method and application thereof are provided.
Disclosure of Invention
The invention aims to provide a piezoelectric composite membrane for wound healing, a preparation method and application thereof, and aims to solve the problems in the background art.
In order to achieve the above purpose, the present invention provides the following technical solutions:
a method of preparing a piezoelectric composite membrane for wound healing, comprising the steps of:
S1, dissolving PVDF powder in a DMF/acetone mixed solvent, and adding dopamine powder into the mixed solution;
step S2, after the mixed solution in the step S1 is fully mixed through ultrasonic vibration, stirring 12 to h at the temperature of 70 ℃ by using a magnetic stirrer to form a uniform DA/PVDF mixed solution;
and S3, spinning the uniform DA/PVDF solution by using a standard laboratory setting and using filter cloth as a supporting material and adopting an electrostatic spinning technology to prepare the DA/PVDF piezoelectric composite membrane, and drying at room temperature for later use.
Further, in the step S1, the mass concentration of PVDF powder is 150 mg/ml; the volume ratio v/v of the DMF/acetone mixed solvent is 7:3; the mass concentration of the dopamine powder is 1.5 mg/ml.
Further, in the step S2, the time of the ultrasonic oscillation is 90 min.
Further, in step S3, the standard laboratory setup includes a spinning jet connected to a power source, a syringe pump, and a grounded collector.
Further, in the step S3, the conveying rate in the electrostatic spinning process is 1.0 mL/h, the applied voltage is 18 kV, the distance between the spinning machine and the collector is 15 cm, and the air humidity is 37.
A piezoelectric composite membrane for wound healing prepared by the preparation method described above.
Use of a piezoelectric composite membrane for wound healing as described above for the preparation of a bioactive material for promoting wound healing.
Compared with the prior art, the invention has the beneficial effects that:
The invention provides a DA/PVDF piezoelectric composite membrane (hereinafter referred to as DA/PVDF membrane) activated by LIPUS, which can promote wound healing. Under ultrasonic stimulation, the electrical output of the DA/PVDF membrane is significantly enhanced, which indicates that the membrane can generate stable local electrical stimulation; and the DA/PVDF membrane is more beneficial to cell adhesion by modifying dopamine, and is beneficial to forming a continuous cell layer on the surface of the membrane. In addition, the cell viability and mobility of the DA/PVDF membrane are obviously increased under the ultrasonic stimulation, and particularly, the DA/PVDF membrane shows obvious enhancement effect under the high-power ultrasonic treatment. In addition, in animal experiments, the DA/PVDF membrane remarkably improves the healing effect of wound surfaces under ultrasonic stimulation, has better effect than independent LIPUS treatment or other commercial control groups, promotes the deposition of type I collagen at wound sites, and reflects the structural remodeling advantage of the DA/PVDF membrane in the wound healing process. Meanwhile, the DA/PVDF membrane has good in vivo biological safety under ultrasonic stimulation, and provides an innovative, safe and effective treatment method for wound healing.
Drawings
FIG. 1is a graph of the results of the preparation and characterization of DA/PVDF membranes of the present invention; wherein a is the nanofiber microstructure of the PVDF film and the DA/PVDF film; b is the relative diameter distribution of the PVDF membrane and the DA/PVDF membrane; c is a graph of FTIR analysis results for PVDF and DA/PVDF membranes.
FIG. 2 is a graph showing the results of piezoelectric performance characterization of the DA/PVDF membrane of the present invention; wherein a is the output voltage generated by exposing the PVDF film to low frequency pulse ultrasonic waves with the power of 1.0W/cm 2; b is the output voltage generated by exposing the DA/PVDF film to low-frequency pulse ultrasonic waves with the power of 1.0W/cm 2; c is the output voltage generated by exposing the DA/PVDF film to low-frequency pulse ultrasonic waves with the power of 0-1.0W/cm 2; d is an output voltage experimental diagram of the DA/PVDF membrane placed on the skin of a mouse and exposed to low-frequency pulse ultrasonic waves.
FIG. 3 is a graph showing the effect of DA/PVDF membrane of the present invention on cell adhesion; wherein a is a laser confocal image of L929 cells after 24h culture on a PVDF and DA/PVDF nanofiber scaffold under the stimulation of LIPUS on (1.0W/cm 2) and LIPUS off conditions; b is SEM image of PVDF film and DA/PVDF film fixed on the back wound 24h of mice under LIPUS (1.0W/cm 2) stimulation; c is another SEM image of PVDF membrane and DA/PVDF membrane at wound 24h fixed on the back of mice under LIPUS (1.0W/cm 2) stimulation.
FIG. 4 is a graph showing the effect of DA/PVDF membrane of the present invention on cell proliferation and migration; wherein, a is the change of （0 W/cm2、0.2 W/cm2、0.4 W/cm2、0.6 W/cm2、0.8 W/cm2、1.0 W/cm2） cell vitality under different ultrasonic power intensities of L929 fibroblasts inoculated in PVDF membrane and DA/PVDF membrane; b is the change of cell viability at different ultrasonic power intensities (0W/cm 2、1.0 W/cm2) after 3 days of incubation; c is a cell mobility statistical graph of the scratch experiment; d is a statistical plot of cell numbers in the lower chamber; e is an image of cells migrating in the lower chamber.
FIG. 5 is a graph showing the effect of DA/PVDF membrane of the present invention on the regeneration and repair of a full-thickness skin defect model of a mouse; wherein a is a back wound surface photograph of the mice grouped into different time nodes of day 0, day 3, day 7 and day 14 in vivo; b is the rate of wound healing for the different groups; c is the statistical result of different groups of collagen; d is H & E staining images of tissues around different groups of wound surfaces at 14 days; e is the Masson stained image of the tissue surrounding the different sets of wounds at the remodelling stage of wound healing.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
Specific implementations of the invention are described in detail below in connection with specific embodiments.
The preparation method of the piezoelectric composite membrane for wound healing provided by one embodiment of the invention comprises the following steps:
step one, PVDF powder (mW=5.34 kDA) was dissolved in DMF/acetone mixed solvent (7:3 v/v) at 150 mg/ml, and Dopamine (DA) powder (98%) was added to the mixed solution at 1.5 mg/ml.
And step two, after the mixed solution in the step one is fully mixed by ultrasonic vibration 90min, stirring 12 to h by using a magnetic stirrer at 70 ℃ to form a uniform DA/PVDF mixed solution.
Step three, standard laboratory setup included a spinning jet connected to a high voltage power supply, a syringe pump, and a grounded collector. The conveying speed of the electrostatic spinning process is 1.0 mL/h, the applied voltage is 18 kV, the distance between the spinning device and the collector electrode is 15 cm, and the air humidity is 37. And (3) taking the filter cloth as a supporting material, spinning the uniform DA/PVDF solution by adopting an electrostatic spinning technology, preparing the DA/PVDF film, and drying at room temperature for later use.
Step four, the DA/PVDF film is exposed to low frequency pulse ultrasonic waves with the power of 1.0W/cm 2, and the output power of 450 mV can be measured.
As a preferred embodiment of the present invention, the DA/PVDF film in the fourth step is placed on the skin of the mouse and then exposed to low frequency pulsed ultrasonic waves, and the DA/PVDF film can generate a stable output voltage to regulate wound repair.
Characterization of the DA/PVDF membranes of example 1;
The DA/PVDF film was prepared in the first to third steps, and in the examples, 1.0 wt% of DA molecules were added, and the microstructure was observed by a scanning electron microscope (Scanning Electron Microscope, SEM), and the particle size was analyzed by a nanoparticle analyzer (Nanoparticle Size Analyzer).
The DA/PVDF membrane was chemically characterized using a Fourier transform infrared spectrometer (Fourier-Transform Infrared Spectroscopy, FTIR).
The results show that the diameter distribution of the DA/PVDF membrane obtained by electrospinning is uniform (732+ -232 nm), and similar to that of the original PVDF membrane (712.34 + -163.42 nm). The nanofiber microstructure of the DA/PVDF membrane is shown in FIG. 1a, the related diameter distribution of the DA/PVDF membrane is shown in FIG. 1b, and the preparation method of the membrane is verified. In FIG. 1, c is the result of FTIR analysis, showing that there is a distinct peak at 840 cm -1 for both PVDF and DA/PVDF membranes, due to the polar beta phase, where the characteristic peak of the PVDF membrane at 1.0 wt% DA is the strongest. Characteristic peaks of the nonpolar alpha phase such as 763 cm -1、796 cm-1 do not appear as significant strong peaks in both nanofiber membranes, which may be due to the effect of electrospinning.
Example 2, characterization of piezoelectric properties of DA/PVDF membrane;
1. The electrical output of DA/PVDF membranes was studied in the range of 0-1.0W/cm 2. In the output measurement, the ultrasonic frequency was set to 1 MHz.
2. The influence of low-frequency pulse ultrasonic waves with different power intensities on the output performance of the DA/PVDF film is studied.
3. The DA/PVDF membrane was placed on the skin of the mice, then exposed to low frequency pulsed ultrasound, and the output voltage was recorded.
The results show that exposure of PVDF film to low frequency pulsed ultrasonic waves at a power of 1.0W/cm 2 produced an output voltage of 350 mV (a in fig. 2), and that when 1.0 wt% DA was added, the output power of the DA/PVDF film was increased to 450 mV by a factor of about 1.3 (b in fig. 2). When the power intensity was increased from 0W/cm 2 to 1.0W/cm 2, the electrical output of the DA/PVDF membrane was greatly increased (c in FIG. 2).
In fig. 2d is the output voltage of the DA/PVDF film placed on the skin of a mouse, exposed to low frequency pulsed ultrasound, showing that the DA/PVDF film can produce an output voltage of (-50 mV), indicating that it is feasible to deliver an electrical potential to the wound site under ultrasound stimulation. Thus, low frequency pulsed ultrasound responsive DA/PVDF membranes may be suitable for biomedical applications.
Example 3, effect of DA/PVDF membrane on cell adhesion;
1. mouse fibroblast L929 cell line was seeded onto PVDF and DA/PVDF membranes (1X 1 cm 2) at a density of 5X10 4 cells per group, and after cell attachment, the PVDF and DA/PVDF groups were stimulated with LIPUS (1.0W/cm 2), each group being 5 min, followed by 24 h incubation.
2.24 After h, the L929 cell line was subjected to live and dead staining using calcein/propidium iodide kit (AM/PI, solarbio, china), followed by fixation with 4% paraformaldehyde, followed by three washes with PBS, followed by incubation with 37.4 μm calcein and 5 μm propidium iodide at 30 ℃ for 2 min, followed by three washes with PBS, dead and live cells showing red and green fluorescence, respectively.
3. The growth state of L929 cells on PVDF film and DA/PVDF film was observed by laser confocal microscope ((FLUOVIEW FV Olympus China) and SEM, both scanning electron microscope and laser confocal image clearly showed the effect of DA/PVDF film on cell adhesion, DA presence accelerated the adhesion process of L929 cells these results show that DA/PVDF nanofiber film has remarkable advantage in promoting cell adhesion, and is expected to play an important role in tissue engineering and biomedical applications.
FIG. 3a is a laser confocal image of L929 cells after 24-h incubation on PVDF and DA/PVDF nanofiber scaffolds under stimulation of LIPUS on (1.0W/cm 2) and LIPUS off conditions. Since our PVDF samples are hydrophobic, cell adhesion to the sample is weak. The DA modified electrospun PVDF membrane is more conducive to cell adhesion, which is further enhanced upon stimulation in combination with LIPUS.
In FIG. 3b and c are SEM images of PVDF membrane and DA/PVDF membrane fixed on the back wound 24h of mice under LIPUS (1.0W/cm 2) stimulation. To verify the actual recruitment of cells to the wound site by the DA/PVDF membrane under LIPUS stimulation, we fixed the PVDF membrane and DA/PVDF membrane to the back wound of the mice, stimulated the nanofiber membrane on the back of the mice with LIPUS (1.0W/cm 2) (5 min/24 h), sampled after 24h and scanned by electron microscopy. The results show that after LIPUS stimulation (1.0W/cm 2) a broader cell adhesion was observed on the DA/PVDF membrane compared to the PVDF group, while the cells were in an elongated and stretched form and mixed to form a continuous cell layer. Both scanning electron microscopy and laser confocal images showed that the DA/PVDF nanofiber membrane favors cell adhesion and accelerates this process under stimulation by LIPUS (1.0W/cm 2).
Example 4, effect of DA/PVDF membrane on cell proliferation and migration;
to evaluate the effect of DA/PVDF membrane on cell proliferation and migration under LIPUS stimulation, in vitro cell proliferation and migration experiments were performed.
1. L929 fibroblasts were inoculated in PVDF membrane, DA/PVDF membrane, and cultured continuously for 3 days. The control group was cells cultured directly on polystyrene plates (TCPS).
2. The change in cell viability (0-1.0W/cm 2) at different ultrasonic power intensities was examined using CCK-8 and the results represent its effect on cell proliferation performance.
3. Cell scratch experiments were performed to investigate cell migration behaviour under ultrasound stimulation. L929 cells were inoculated into PVDF membrane, DA/PVDF membrane and well plate, respectively, and cultured, 24 h was followed by drawing a straight line on the culture plate or membrane with a 200. Mu.L pipette tip, and the adherent L929 cells were directly scratched and divided into an sonicated group and a non-sonicated group. It can be seen that the scratch edges of different groups gradually migrate at different rates to the blank area, and that the cell mobility (M%) is expressed as a change in scratch area at different times, quantified using Image J software. The calculation is carried out by using the formula: m% = (A0-AT) ×100%/A0, where A0 is the initial scratch area measured immediately after the scratch and AT is a different time after the scratch (t=24 h).
4. Transwell experiments were performed to investigate cell migration behaviour under ultrasound stimulation. The cells above the Transwell plate were divided into untreated groups, PVDF groups and DA/PVDF groups, which were covered with PVDF film and DA/PVDF film, respectively, to ensure separation from the lower chamber. L929 fibroblasts were inoculated into the upper chamber and subjected to ultrasonic stimulation treatment or no treatment. After incubation of 24h, the cells were removed, stained with crystal violet, photographed with a microscope into images of cells migrating in the lower chamber, and quantitatively analyzed for cell number using Image J or other software.
CCK8 results are shown in FIGS. 4 a and b, and the cell viability was slightly increased on PVDF membrane and DA/PVDF membrane compared to control group without LIPUS treatment (0W/cm 2), wherein DA/PVDF group is superior to common PVDF group. The DA/PVDF membrane increased in cell viability compared to the control when LIPUS power was adjusted to 0.2W/cm 2、0.6 W/cm2、0.8 W/cm2, but decreased slightly in cell viability under the excitation conditions of 0.4W/cm 2 compared to the control. In general, under these power conditions, cell viability on the DA/PVDF membrane did not show significant differences. However, under high power sonication (i.e., 1.0W/cm 2), the viability of cells seeded on the cell membrane increased. After 3 days of incubation (b in FIG. 4), when the LIPUS power intensity was adjusted to 1.0W/cm 2, the cell viability on the DA/PVDF membrane was 1.14 times that of the blank group, resulting in a significant difference (P < 0.5). The DA/PVDF membrane can deliver electrical stimulation to fibroblasts in response to ultrasound and up-regulate growth factor levels, thereby promoting cell proliferation.
The results of the scratch experiments are shown in FIG. 4c, where the DA/PVDF membrane was almost completely healed after 24. 24 h with the highest cell mobility (14.62%) when the LIPUS power intensity was adjusted to 1.0W/cm 2. In contrast, the cell mobility of the cell membrane without sonication is much lower, 4.63%. The ultrasonic stimulation also improves the scratch healing effect of the PVDF membrane, and the cell mobility (11.70%) is weaker than the DA/PVDF group effect. The electric field generated by the cell membrane under ultrasonic treatment can promote the migration of the marginal cells. The cell mobility of the DA/PVDF group was significantly higher than that of the PVDF group and the control group (as can be seen from e in FIG. 4) at an ultrasonic power intensity of 1.0W/cm 2.
In FIG. 4, d and e are Transwell results, similar to the scoring results, when LIPUS power intensity was adjusted to 1.0W/cm 2, few cells in the blank and PVDF groups were recruited to the lower chamber (P > 0.5), as compared to more cells in the lower chamber of the DA/PVDF group (e in FIG. 4).
The results show that the ultrasonic wave can stimulate cell membranes and promote proliferation and migration behaviors of cells.
Example 5 effect of DA/PVDF membrane on regeneration repair of full-thickness skin defect model of mice;
1. skin defects can be classified into epidermis skin wounds, shallow part thickness skin wounds, deep part thickness skin wounds and full layer skin wounds according to the depth of the injury, and the influence of an ultrasonic activated piezoelectric film on wound healing behaviors is evaluated by using a mouse back full layer wound model.
2. The in vivo groupings are as follows: simple defect group (Control group), fibrin treatment group (commercial Control group), LIPUS group, DA/PVDF group, DA/pvdf+lipus group. The method comprises the following specific steps: after 6 weeks of mice (weight 18±1 g) were prepared and anesthetized, the backs of the mice were dehaired, and full-thickness skin cut wounds of about 10 x 10 mm in size were established on the backs with scissors, and the respective treatments were performed on the wounds in groups.
3. The wound healing rate was recorded and analyzed, mice were euthanized after 14 days, the periwound skin was collected, histologically sectioned HE stained, and Masson's trichrome staining stained for collagen fiber deposition.
Fig. 5 a shows photographs of the back wound of mice grouped at different time nodes on days 0, 3, 7, and 14 in vivo. In fig. 5b is the rate of wound healing for the different groups, the relative wound area is defined as the percentage of At/A0, where A0 is the initial wound area and At is the wound area measured on different days (e.g. t=0, 3, 7, 14). As shown in fig. 5 a, the wound of the blank control group is slow to heal, a larger wound area (to 77.47%) is still reserved on the 3 rd day, the wound area on the 7 th day is about 69.38%, and the larger wound is still incompletely healed (to 17.30%) after 14 days. When LIPUS ultrasound was applied alone at the wound site, the wound site healing rate was only slightly higher than the control group. The wound area of the LIPUS group was approximately 74.26% on day 3, and the wound area on days 7 (68.20%) and 14 (17.71%) was very similar to the control group. Thus, the healing effect of pure LIPUS treatment is low. When the DA/PVDF membrane was applied to the wound site, the wound area (60.43%) was significantly different from that of the control group for 3 days, and the healing effect was better (40.23%) at 7 days, whereas on day 14, the wound healing was slower (wound area about 19.75%) for the DA/PVDF membrane group, so that only the initial healing of the wound (3 days, 7 days) was accelerated when the DA/PVDF membrane was used alone. The wound area of DA/PVDF under ultrasound stimulation was significantly reduced (38.34%) over the other groups over the first 3 days, and surprisingly, the healing efficiencies of the DA/PVDF+LIPUS groups were even better than that of the commercial fibrin glue groups on days 3 (46.13%), 7 (32.50%), 14 (18.62%), with significant differences (P < 0.5). These results demonstrate that wound healing can be efficiently promoted using LIPUS + piezoelectric film to impart wound stimulation.
Fig. 5d shows H & E stained images of tissue surrounding the different sets of wounds at 14 days. Intact epidermis was formed in dermal tissue of the DA/PVDF+LIPUS group, while other groups had excessive thickening of partially regenerated epithelium. In addition, the DA/PVDF+LIPUS group is faster in terms of structural remodeling than other groups, such as the skin appendages hair follicles and sebaceous glands are updated.
In fig. 5 e is a map of Masson staining of the tissue surrounding the wound of the different groups, collagen fibers were deposited and remodeled from type III to type I during the remodelling phase of wound healing. At the same time, the collagen fibers are aligned along a tensile line and are closely crosslinked together. Masson trichromatic staining showed that the control group had less collagen fibers at early stages of wound healing (3-7 days). The collagen statistics also indicate (fig. 5 c) that the type I collagen deposition was significantly higher in the DA/pvdf+lipus group than in the other groups. In the later stages of wound healing (14 days), the collagen fibers of the DA/PVDF+LIPUS group were more ordered as collagen fiber deposition increased (d in FIG. 5). Whereas the control collagen fibers were irregular and spiral. These results indicate that LIPUS is an effective and safe treatment. The combination of the DA/PVDF piezoelectric film and LIPUS significantly accelerates the wound healing process.
In summary, the DA/PVDF membrane activated by LIPUS provided by the invention can generate stable local electrical stimulation under ultrasonic stimulation, and is more beneficial to cell adhesion by modification of dopamine, so that cells can form a continuous cell layer on the surface of the membrane. In addition, the cell viability and mobility of the DA/PVDF membrane are obviously increased under the ultrasonic stimulation, and particularly, the DA/PVDF membrane shows obvious enhancement effect under the high-power ultrasonic treatment. In addition, in animal experiments, the DA/PVDF membrane remarkably improves the healing effect of wound surfaces under ultrasonic stimulation, promotes the deposition of type I collagen at wound sites, shows the advantage of structural remodeling in the wound healing process, and provides an innovative, safe and effective treatment method for wound healing.
The foregoing is merely a preferred embodiment of the present invention, and it should be noted that modifications and improvements can be made by those skilled in the art without departing from the spirit of the present invention, and these should also be considered as the scope of the present invention, which does not affect the effect of the implementation of the present invention and the utility of the patent.
Claims (7)
1. A method for preparing a piezoelectric composite membrane for wound healing, comprising the steps of:
S1, dissolving PVDF powder in a DMF/acetone mixed solvent, and adding dopamine powder into the mixed solution;
step S2, after the mixed solution in the step S1 is fully mixed through ultrasonic vibration, stirring 12 to h at the temperature of 70 ℃ by using a magnetic stirrer to form a uniform DA/PVDF mixed solution;
And S3, spinning the uniform DA/PVDF mixed solution by using a standard laboratory setting and using filter cloth as a supporting material and adopting an electrostatic spinning technology to prepare the DA/PVDF piezoelectric composite membrane, and drying at room temperature for later use.
2. The method for preparing a piezoelectric composite membrane for wound healing according to claim 1, wherein in the step S1, the mass concentration of PVDF powder is 150 mg/ml; the volume ratio v/v of the DMF/acetone mixed solvent is 7:3; the mass concentration of the dopamine powder is 1.5 mg/ml.
3. The method of claim 1, wherein in step S2, the time of ultrasonic vibration is 90 min.
4. The method of preparing a piezoelectric composite film for wound healing according to claim 1, wherein in the step S3, the standard laboratory setup comprises a spinning jet connected to a power source, a syringe pump and a grounded collector.
5. The method according to claim 4, wherein in the step S3, the electrostatic spinning process is carried out at a delivery rate of 1.0 mL/h, the applied voltage is 18 kV, the distance between the spinning machine and the collector is 15 cm, and the air humidity is 37.
6. A piezoelectric composite film for wound healing produced by the production method according to any one of claims 1 to 5.
7. Use of a piezoelectric composite membrane for wound healing according to claim 6 for the preparation of a bioactive material for promoting wound healing.
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| CN115177777A (en) * | 2022-07-07 | 2022-10-14 | 四川大学 | Preparation method of piezoelectric healing-promoting wound repair auxiliary material |
| CN117462573A (en) * | 2023-10-10 | 2024-01-30 | 南方医科大学口腔医院 | Nanometer material for enhancing DCs cyto-burial function and promoting diabetic wound healing and preparation method thereof |
| US20240108783A1 (en) * | 2022-09-30 | 2024-04-04 | Peking University School Of Stomatology | Medical material and product and preparation method thereof |
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| CN109966538A (en) * | 2019-04-02 | 2019-07-05 | 南通大学 | A kind of micro-current wound promotees to be cured antiseptic dressing and preparation method thereof |
| CN113304303A (en) * | 2021-05-18 | 2021-08-27 | 南通大学 | Micro-current elastic dressing for chronic wound healing and preparation method thereof |
| CN115177777A (en) * | 2022-07-07 | 2022-10-14 | 四川大学 | Preparation method of piezoelectric healing-promoting wound repair auxiliary material |
| US20240108783A1 (en) * | 2022-09-30 | 2024-04-04 | Peking University School Of Stomatology | Medical material and product and preparation method thereof |
| CN117462573A (en) * | 2023-10-10 | 2024-01-30 | 南方医科大学口腔医院 | Nanometer material for enhancing DCs cyto-burial function and promoting diabetic wound healing and preparation method thereof |
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