aFGF-loaded bacterial cellulose sutures, their preparation methods and applications

Abstract

This invention relates to the field of biomaterials technology, specifically to a bacterial cellulose suture loaded with aFGF, its preparation method, and its application. The preparation method includes: providing a bacterial cellulose membrane; cutting the bacterial cellulose membrane into strip-shaped components, then weaving the strip-shaped components into a bacterial cellulose suture; immersing the bacterial cellulose suture in an aFGF solution, and drying to obtain the aFGF-loaded bacterial cellulose suture. The preparation process is simple and easy to implement, and the resulting suture has good biocompatibility, promotes wound healing effectively, and also has an anti-adhesion effect.

Description

Technical Field

[0001] This invention relates to the field of biomaterials technology, specifically to a bacterial cellulose suture loaded with aFGF, its preparation method, and its application. Background Technology

[0002] Surgical sutures are long-established and essential suture medical devices, playing a crucial role in closing damaged blood vessels and organs and assisting in postoperative wound healing. Although some products, such as biomedical adhesives, glues, and staples, have been developed as alternatives to sutures, they undeniably still account for more than half of the global surgical instrument market due to their high stability, feasibility, and applicability. Surgical sutures are an ancient device, initially used to aid in wound repair, and have entered a new, intelligent phase in recent decades. Material selection, fiber morphology, suture structure and construction, as well as suture structural modification, functionalization, and even intelligentization are all directions of modern suture research. Material selection is crucial to suture manufacturing, significantly impacting the performance of the final suture. Compared to traditional non-degradable suture materials, absorbable suture materials exhibit unique properties that allow them to degrade in vivo without the need for later excision, thus protecting patients from secondary trauma. While a wide variety of commercial sutures are available clinically, improving the biological performance of currently used sutures remains a significant challenge. Summary of the Invention

[0003] The purpose of this invention is to provide a bacterial cellulose suture loaded with aFGF, its preparation method and application. The preparation process is simple and easy, the suture has good biocompatibility, promotes wound healing, and also has the function of preventing adhesion.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] In a first aspect, the present invention provides a method for preparing bacterial cellulose sutures loaded with aFGF, comprising:

[0006] Provide bacterial cellulose membranes;

[0007] The bacterial cellulose membrane was cut into strips, and then the strips were woven into bacterial cellulose sutures.

[0008] Bacterial cellulose sutures were soaked in aFGF solution and then dried to obtain bacterial cellulose sutures loaded with aFGF.

[0009] Furthermore, the preparation of the bacterial cellulose membrane includes the following steps:

[0010] Step 1: Prepare amplification culture medium and production culture medium;

[0011] Step 2: Pick colonies of Acetobacter xylinum into the amplification medium, shake and incubate to obtain Acetobacter xylinum amplification solution;

[0012] Step 3: Inoculate the Acetobacter xylinum amplification broth into the production culture medium, add anhydrous ethanol and stir well, pour into a petri dish, and place the petri dish in a bacterial constant temperature incubator for static culture to obtain the bacterial cellulose primitive membrane;

[0013] Step four: Wash away the bacterial liquid and residue on the original bacterial cellulose membrane with distilled water, then boil it in sodium hydroxide solution, wash it several times with distilled water, and finally lay it flat on a plate to air dry naturally to obtain the bacterial cellulose membrane.

[0014] Furthermore, the amplification culture medium described in step one includes 3-7 g / L glucose, 3-7 g / L yeast extract, 3-7 g / L polypeptone, and 0.5-1.2 g / L citric acid;

[0015] And / or, the production culture medium described in step one includes 20-40 g / L glucose, 3-7 g / L yeast extract, 3-7 g / L peptone, 0.1-0.25 g / L magnesium sulfate, 0.05-0.1 g / L potassium dihydrogen phosphate, and 0.5-1.2 g / L citric acid.

[0016] Furthermore, the process parameters for the shaking culture in step two include: the rotation speed is set to 150~180 r / min, the temperature is set to 28~30℃, and the shaking culture time is set to 36~48h.

[0017] Furthermore, in step three, 40-80 mL of Acetobacter xylinum amplification broth and 3-8 mL of anhydrous ethanol are added to every 1 L of production culture medium. The temperature of the bacterial constant temperature incubator is set to 28-30℃, and the static culture time is set to 5-10 days.

[0018] Furthermore, the concentration of the aFGF solution was 1~100 μg / L, and the soaking time was set to 1~60 min.

[0019] Furthermore, the strip-shaped member has a width of 1~5mm, a length of 15~25cm, and a thickness of 0.8~1.5mm.

[0020] Furthermore, the weaving pattern of the strip-shaped components is a single spiral, a double spiral, or a three-strand braid.

[0021] Secondly, the present invention provides a bacterial cellulose suture loaded with aFGF, which is prepared by the above-described preparation method.

[0022] Thirdly, the present invention provides an application of the bacterial cellulose suture loaded with aFGF prepared by the above-mentioned preparation method in medical dressings.

[0023] The present invention has the following unexpected beneficial effects:

[0024] 1. This invention uses bacterial cellulose as a substrate to weave bacterial cellulose sutures. Compared with traditional plant cellulose, bacterial cellulose retains a similar framework at the molecular level, but eliminates redundant components such as lignin, hemicellulose, and pectin, resulting in superior performance. Higher crystallinity gives it structural robustness, enhanced stability ensures reliable performance in various environments, and excellent biocompatibility further broadens its application boundaries in the biomedical field. The high water-holding capacity and good biodegradability of bacterial cellulose make it an environmentally friendly material, which can be absorbed and degraded by the human body to a certain extent without toxic side effects. Therefore, preparing surgical sutures from bacterial cellulose has significant clinical value. Furthermore, given the excellent specific surface area and fiber porosity of bacterial fibers, drugs such as aFGF can be loaded, and combined use can further improve wound healing quality.

[0025] 2. The preparation process of this invention generates no waste gas or waste liquid, which is environmentally friendly, and the operation is simple and easy to implement with low cost. Attached Figure Description

[0026] Figure 1 A flowchart illustrating the preparation method of bacterial cellulose suture loaded with aFGF provided in an embodiment of the present invention is shown.

[0027] Figure 2 A flowchart illustrating the preparation method of bacterial cellulose membrane provided in an embodiment of the present invention is shown.

[0028] Figure 3 A flowchart is shown for bacterial cellulose sutures loaded with aFGF and stained with methylene blue.

[0029] Figure 4 The SEM image of the surface morphology of the bacterial cellulose membrane prepared according to the present invention is shown.

[0030] Figure 5 A statistical graph showing the in vitro degradation of the bacterial cellulose membrane prepared according to the present invention is shown.

[0031] Figure 6 The surface morphology of bacterial cellulose sutures, methylene blue-stained bacterial cellulose sutures, and methylene blue-stained double-helix bacterial cellulose sutures loaded with aFGF are shown.

[0032] Figure 7 A statistical graph of the tensile strength of bacterial cellulose sutures after stretching is shown.

[0033] Figure 8 The graph shows the elongation of the bacterial cellulose suture after stretching.

[0034] Figure 9 The surface morphology of the fractured end of the bacterial cellulose suture after stretching is shown in the diagram.

[0035] Figure 10 The results of the cell compatibility test for bacterial cellulose sutures are shown in the figure.

[0036] Figure 11 The results of the blood compatibility test for bacterial cellulose sutures are shown in the figure.

[0037] Figure 12 The results of the in vivo biocompatibility test for bacterial cellulose sutures are shown in the figure.

[0038] Figure 13 HE and Masson plots at different time points are shown for bacterial cellulose sutures and commercial silk sutures used for subcutaneous embedding.

[0039] Figure 14 The image shows the effect of bacterial cellulose sutures on skin closure of rat wounds.

[0040] Figure 15 The image shows the effect of bacterial cellulose sutures on tendon suturing in rats.

[0041] Figure 16 The image shows the effect of bacterial cellulose sutures on the closure of gastric perforation in rats.

[0042] Figure 17 The image shows the effect of bacterial cellulose sutures on the suturing of rat intestinal incisions. Detailed Implementation

[0043] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0044] In one embodiment, see Figure 1 As shown, the present invention provides a method for preparing bacterial cellulose sutures loaded with aFGF, comprising:

[0045] Bacterial cellulose membranes are provided; bacterial cellulose membranes are the starting material for preparing sutures. These membranes have excellent mechanical properties, biocompatibility, and absorbability, making them ideal for use in the medical field.

[0046] The bacterial cellulose membrane is cut into strips, a step that transforms the membrane material into a shape suitable for weaving into thread. The cutting process requires precise control of the strip width and length to ensure the strength and suitability of the final suture. These strips are then woven into bacterial cellulose sutures; the weaving process increases the suture's strength and flexibility, making it more suitable for suturing wounds.

[0047] The bacterial cellulose sutures are soaked in an aFGF solution. This step is to ensure that aFGF is evenly loaded onto the sutures. aFGF promotes wound healing and cell regeneration, therefore aFGF-loaded sutures have significant advantages in medical applications.

[0048] The bacterial cellulose sutures loaded with aFGF are obtained by air drying. The drying process requires control of appropriate temperature and humidity to ensure that aFGF can stably adhere to the sutures while avoiding adverse effects on the mechanical properties of the sutures. Exemplary drying methods include natural room temperature air drying, oven drying, or dry drying.

[0049] aFGF is the abbreviation for acidic fibroblast growth factor.

[0050] This invention uses bacterial cellulose as a substrate to weave bacterial cellulose sutures. Compared to traditional plant cellulose, bacterial cellulose, while retaining a similar framework at the molecular level, eliminates redundant components such as lignin, hemicellulose, and pectin, resulting in superior performance. Higher crystallinity gives it structural robustness, enhanced stability ensures reliable performance in various environments, and excellent biocompatibility further broadens its application boundaries in the biomedical field. The high water-holding capacity and good biodegradability of bacterial cellulose make it an environmentally friendly material, capable of being absorbed and degraded by the human body to a certain extent without toxic side effects. Therefore, preparing surgical sutures from bacterial cellulose has significant clinical value. Furthermore, given the excellent specific surface area and fiber porosity of bacterial fibers, drugs, such as aFGF, can be loaded, and combined use can further improve wound healing quality.

[0051] The preparation process of this invention generates no waste gas or waste liquid, making it environmentally friendly. It is also simple to operate and has low cost.

[0052] In a preferred embodiment, see Figure 2 As shown, the preparation of the bacterial cellulose membrane includes the following steps:

[0053] Step one involves preparing the amplification medium and the production medium. The amplification medium is used to initially increase the number of *Acetobacter xylinum*, preparing it for large-scale reproduction in the subsequent production medium. The production medium provides the nutrients required for the growth of *Acetobacter xylinum* to support its synthesis of bacterial cellulose.

[0054] Step 2: Pick colonies of Acetobacter xylinum into the amplification medium and shake them to promote the uniform distribution and reproduction of Acetobacter xylinum in the amplification medium, thus obtaining the Acetobacter xylinum amplification solution.

[0055] Step 3: Inoculate the Acetobacter xylinum amplification broth into the production medium to begin the bacterial cellulose synthesis process. Add anhydrous ethanol and stir well, pour into a petri dish, and place the petri dish in a bacterial constant temperature incubator for static incubation. Under suitable temperature and humidity conditions, allow Acetobacter xylinum to grow statically on the production medium to synthesize the bacterial cellulose primitive membrane.

[0056] Step four involves washing the original bacterial cellulose membrane with distilled water to remove bacterial culture and residues, thus removing excess bacteria and culture medium components. The membrane is then boiled in a sodium hydroxide solution to remove impurities such as proteins and polysaccharides, which also helps improve the membrane's texture and performance. This is followed by multiple washes with distilled water to thoroughly remove sodium hydroxide and any other possible residues. Finally, the membrane is laid flat on a plate to air dry, allowing it to dry and set, facilitating subsequent cutting and weaving.

[0057] Furthermore, the amplification culture medium described in step one comprises 3-7 g / L glucose, 3-7 g / L yeast extract, 3-7 g / L polypeptone, and 0.5-1.2 g / L citric acid. Glucose serves as a carbon source, providing energy for *Acetobacter xylinum*. Yeast extract provides various amino acids, vitamins, and trace elements, promoting the growth of *Acetobacter xylinum*. Polypeptone provides a nitrogen source and essential amino acids, supporting bacterial growth and reproduction. Citric acid can be used to adjust the pH of the culture medium and also serves as a carbon source.

[0058] The production culture medium described in Step 1 comprises 20–40 g / L glucose, 3–7 g / L yeast extract, 3–7 g / L polypeptone, 0.1–0.25 g / L magnesium sulfate, 0.05–0.1 g / L potassium dihydrogen phosphate, and 0.5–1.2 g / L citric acid. Higher glucose concentrations are beneficial for bacterial cellulose synthesis. The concentration range may be chosen based on specific production conditions and target yield. Yeast extract also provides amino acids, vitamins, and trace elements, supporting bacterial growth and cellulose synthesis. Polypeptone provides a nitrogen source, which is crucial for bacterial cellulose synthesis. Magnesium sulfate, as an inorganic salt, plays an important role in bacterial growth and metabolism. Potassium dihydrogen phosphate provides phosphorus and also helps regulate the pH of the culture medium. Citric acid is also used to regulate the pH and may serve as an additional carbon source.

[0059] Furthermore, the process parameters for shaking culture in step two include: the rotation speed is set to 150~180 r / min. An appropriate rotation speed can promote oxygen exchange and uniform distribution of nutrients in the culture medium, which is beneficial to the growth and reproduction of Acetobacter xylinum.

[0060] The temperature is set at 28~30℃, which is a suitable temperature range for the growth of Acetobacter xylinum and can maintain its high metabolic activity.

[0061] The shaking culture time was set to 36-48 hours, which was sufficient for Acetobacter xylinum to reach a certain quantity in the amplification medium, preparing for subsequent inoculation and production.

[0062] Furthermore, in step three, 40-80 mL of *Acetobacter xylinum* amplification broth and 3-8 mL of anhydrous ethanol are added to every 1 L of production culture medium. The amount of amplification broth added ensures a sufficient number of bacteria to synthesize bacterial cellulose. The specific amount of anhydrous ethanol provides a carbon source, promoting bacterial growth and reproduction. Bacteria utilize anhydrous ethanol for metabolism, producing energy, which is used for the synthesis and secretion of bacterial cellulose. In addition, anhydrous ethanol may affect the osmotic pressure and pH of the culture medium, thus indirectly affecting the bacterial growth environment and further influencing the yield and quality of bacterial cellulose. The temperature of the bacterial incubator is set at 28-30℃, which is conducive to maintaining stable bacterial growth and cellulose synthesis. The static incubation time is set at 5-10 days; long-term static incubation allows *Acetobacter xylinum* to grow fully and synthesize a large amount of bacterial cellulose.

[0063] In a preferred embodiment, the concentration of the aFGF solution is 1~100 μg / L. This concentration range ensures that aFGF can be uniformly adsorbed onto the bacterial cellulose membrane while avoiding potential side effects from excessively high concentrations. The soaking time is set to 1~60 min; an appropriate soaking time allows aFGF to fully penetrate the interior of the bacterial cellulose membrane, improving loading efficiency.

[0064] In a preferred embodiment, the width of the strip member is 1-5 mm, a width range that provides both strength and ease of weaving and sewing. The length is 15-25 cm, a length range suitable for most sewing needs while ensuring sufficient operating space. The thickness is 0.8-1.5 mm; a uniform thickness helps maintain the consistency and stability of the strip member.

[0065] In a preferred embodiment, the strip-shaped component is woven in a single spiral, double spiral, or triple braid pattern. These weaving patterns provide different appearance and strength characteristics, and a suitable pattern can be selected according to specific needs.

[0066] Preferably, the strip-shaped component is woven in a double helix pattern, using double-stranded bacterial cellulose to create a double-helix bacterial cellulose suture. This not only further improves its mechanical properties but also makes its smoothness more suitable for wound adhesion. Specifically, the number of helices is 2 to 6 helices per 1 cm.

[0067] In one embodiment, the present invention provides a bacterial cellulose suture loaded with aFGF, which is prepared by the above-described preparation method.

[0068] In one embodiment, the present invention provides the application of the bacterial cellulose suture loaded with aFGF prepared by the above preparation method in medical dressings.

[0069] Specifically, the application of aFGF-loaded bacterial cellulose sutures in the preparation of medical dressings suitable for contact with skin, organs, and blood. Preferably, the medical dressings for contact with skin, organs, and blood refer to medical devices used for suturing wounds in different organs of the human body.

[0070] The following analysis and explanation will be based on specific examples.

[0071] See Figure 3 As shown, a method for preparing bacterial cellulose sutures loaded with aFGF includes the following steps:

[0072] S1, providing a bacterial cellulose membrane; the preparation of the bacterial cellulose membrane includes the following steps:

[0073] Step one: Prepare the amplification medium and the production medium. The amplification medium comprises 5 g / L glucose, 5 g / L yeast extract, 5 g / L peptone, and 1 g / L citric acid. The production medium comprises 30 g / L glucose, 5 g / L yeast extract, 5 g / L peptone, 0.2 g / L magnesium sulfate, 0.75 g / L potassium dihydrogen phosphate, and 1 g / L citric acid.

[0074] Step 2: Pick colonies of Acetobacter xylinum and place them in the amplification medium. Shake and culture for 40 hours at 180 r / min and 30℃ to obtain Acetobacter xylinum amplification solution.

[0075] Step 3: Inoculate 60 mL of Acetobacter xylinum amplification broth into 1 L of production medium, add 5 mL of anhydrous ethanol and stir well, pour into a petri dish, and place the petri dish in a bacterial constant temperature incubator at 30℃ for static culture for 7 days to obtain the bacterial cellulose primitive membrane.

[0076] Step four: Wash away the bacterial culture and residues on the original bacterial cellulose membrane with distilled water, then boil in a 0.2M sodium hydroxide solution for 60 minutes. Wash repeatedly with distilled water to thoroughly remove sodium hydroxide and other possible residues. Finally, lay it flat on a plate to air dry naturally, allowing the bacterial cellulose membrane to dry and set.

[0077] S2. Cut the bacterial cellulose membrane into strips, and then weave these strips into bacterial cellulose sutures. Specifically, use a ruler to cut the bacterial cellulose membrane into strips 5mm wide and 25cm long according to the markings. Then, soak the bacterial cellulose strips in distilled water and rinse three times. Next, weave the strips into bacterial cellulose sutures in a double helix structure (4 helixes / 1cm) and let them air dry. The resulting bacterial cellulose suture is denoted as BCS.

[0078] Methylene blue was used to stain bacterial cellulose sutures. Methylene blue is a positively charged basic dye that can bind to the negatively charged DNA and RNA to form methylene blue-DNA or methylene blue-RNA complexes. When methylene blue binds to these nucleic acids, it absorbs light of specific wavelengths and reflects different colors, thus staining the cell nucleus and cytoplasm. In the staining process of bacterial cellulose sutures, methylene blue primarily stains the nucleic acid and protein components within them.

[0079] Specifically, the steps include the following:

[0080] S21, Prepare bacterial cellulose sutures: Ensure the bacterial cellulose sutures are clean and free of impurities, and prepare an appropriate amount of methylene blue staining solution.

[0081] S22, Staining: Immerse the bacterial cellulose suture in methylene blue staining solution, ensuring complete submersion. The staining time can be adjusted as needed, but typically ranges from a few minutes to several hours to achieve the desired staining effect.

[0082] S23, Rinsing: Gently wash the stained bacterial cellulose sutures with deionized water or buffer to remove excess stain. The washing process should be gentle to avoid damaging the structure of the cellulose sutures.

[0083] S24, Drying: The washed bacterial cellulose sutures are dried naturally or by a suitable drying method (such as low-temperature drying). The resulting product is denoted as BC-MBS.

[0084] S3, the bacterial cellulose suture was immersed in an aFGF solution and then air-dried to obtain aFGF-loaded bacterial cellulose suture. Specifically, an aFGF solution with a concentration of 10 μg / mL was prepared, and the air-dried bacterial cellulose suture was immersed in the aFGF solution for 5 minutes. After immersion, the immersed bacterial cellulose suture was removed and air-dried naturally to obtain aFGF-loaded double-helix bacterial cellulose suture. The obtained product is denoted as BC-MB-aFGFS.

[0085] The obtained product was characterized.

[0086] The surface microstructure of the prepared bacterial cellulose membrane was observed, and the results are shown in [reference]. Figure 4 As shown in the scanning electron microscope images of the bacterial cellulose membrane surface at low and high magnification, it can be seen that the surface of the bacterial cellulose membrane has a uniform texture.

[0087] The in vitro degradation of the prepared bacterial cellulose membrane was observed, and the results are shown in [reference needed]. Figure 5 As shown, the degradation rate of bacterial cellulose sutures in PBS solution from 1 week to 8 weeks reached about 30% at 8 weeks.

[0088] The surface morphology of bacterial cellulose sutures (BCS), methylene blue-stained bacterial cellulose sutures (BC-MBS), and methylene blue-stained double-helix bacterial cellulose sutures (BC-MB-aFGFS) loaded with aFGF was observed. See the results below. Figure 6 As shown, dye particles are visible in methylene blue-stained bacterial cellulose sutures BC-MBS under scanning electron microscopy; crystalline salts containing aFGF are visible on the surface of methylene blue-stained double-helix bacterial cellulose sutures BC-MB-aFGFS.

[0089] The diameter of the bacterial cellulose suture (BCS) was measured to be 156.28 μm.

[0090] Tensile tests were performed on single-strand bacterial cellulose sutures, double-strand bacterial cellulose sutures (BCS), and double-helix bacterial cellulose sutures treated with pH 2.0. Tensile strength and elongation were statistically analyzed. Results are shown in [link to relevant documentation]. Figure 7 and Figure 8As shown, the strain of a single-strand bacterial cellulose suture was 10.65 ± 0.33%, and the stress was 269.01 ± 12.82 MPa. The strain of a double-strand bacterial cellulose suture was 90.57 ± 0.65 MPa, and the stress was 5.45 ± 0.21%. The strain of a double-helix bacterial cellulose suture after immersion in pH 2.0 was 14.38 ± 0.89%, and the stress was 254.25 ± 1.97 MPa. The results show that the mechanical properties of the double-strand bacterial cellulose suture are better than those of the single-strand bacterial cellulose suture, and acid treatment has little effect on the mechanical properties of bacterial cellulose. The surface morphology of the fracture ends of the bacterial cellulose suture after tensile testing is shown in [reference missing]. Figure 9 As shown, the cross-section is flat and smooth, and the two bacterial cellulose fractures are consistent.

[0091] The cell compatibility of the bacterial cellulose suture was tested; the results are shown in [link to results]. Figure 10 As shown, bacterial cellulose sutures have no effect on cell viability, and bacterial cellulose sutures loaded with aFGF can significantly promote cell growth.

[0092] The blood compatibility of the bacterial cellulose suture was tested; the results are shown in [link to results]. Figure 11 As shown, bacterial cellulose sutures do not cause hemolysis of the blood, and the blood is highly safe.

[0093] The in vivo biocompatibility of the bacterial cellulose sutures was tested; results are shown in [link to results]. Figure 12 As shown, bacterial cellulose does not cause tissue infection or lesions in the body and is degradable.

[0094] See Figure 13 HE images of bacterial cellulose sutures and commercial silk sutures at different time points show that bacterial cellulose has good biocompatibility and degradability in vivo.

[0095] The effects of bacterial cellulose sutures on skin closure in rat wounds were tested; results are shown in [link to study]. Figure 14 As shown, where Figure 14 a is a view of the sutured wound. Figure 14 b is the HE image of the sutured wound. Figure 14 c is a Masson plot of the sutured wound, indicating that the bacterial cellulose suture loaded with aFGF has a good effect on promoting wound healing.

[0096] The effects of bacterial cellulose sutures on rat tendon closure were tested; results are shown in [link to study]. Figure 15 As shown, where Figure 15 a is a view of the tendon suture wound. Figure 15 b is a schematic diagram of the stretching of a tendon specimen taken after surgery. Figure 15c shows the statistical diagram of tensile stress in post-tendinectomy specimens. The results indicate that the bacterial cellulose suture loaded with aFGF has good biocompatibility and promotes tendon healing.

[0097] The effects of bacterial cellulose sutures on the closure of gastric perforations in rats were tested; results are shown in [link to results]. Figure 16 As shown, bacterial cellulose sutures loaded with aFGF have a good effect on promoting the healing of gastric perforation wounds, with little rejection reaction and no obvious gastric adhesion.

[0098] The effects of bacterial cellulose sutures on rat intestinal incision closure were tested; results are shown in [link to study]. Figure 17 As shown, bacterial cellulose sutures loaded with aFGF have a good effect on promoting the healing of intestinal incision wounds, with little rejection reaction and minimal intestinal adhesions.

[0099] The above embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention.

Claims

1. A method for preparing bacterial cellulose sutures loaded with aFGF, characterized in that, include: Provide bacterial cellulose membranes; The bacterial cellulose membrane was cut into strips, and then the strips were woven into bacterial cellulose sutures. Bacterial cellulose sutures were soaked in aFGF solution and then dried to obtain bacterial cellulose sutures loaded with aFGF.

2. The method for preparing bacterial cellulose suture loaded with aFGF according to claim 1, characterized in that, The preparation of the bacterial cellulose membrane includes the following steps: Step 1: Prepare amplification culture medium and production culture medium; Step 2: Pick colonies of Acetobacter xylinum into the amplification medium, shake and incubate to obtain Acetobacter xylinum amplification solution; Step 3: Inoculate the Acetobacter xylinum amplification broth into the production culture medium, add anhydrous ethanol and stir well, pour into a petri dish, and place the petri dish in a bacterial constant temperature incubator for static culture to obtain the bacterial cellulose primitive membrane; Step four: Wash away the bacterial liquid and residue on the original bacterial cellulose membrane with distilled water, then boil it in sodium hydroxide solution, wash it several times with distilled water, and finally lay it flat on a plate to air dry naturally to obtain the bacterial cellulose membrane.

3. The method for preparing bacterial cellulose sutures loaded with aFGF according to claim 2, characterized in that: The amplification culture medium described in step one includes 3-7 g / L glucose, 3-7 g / L yeast extract, 3-7 g / L polypeptone and 0.5-1.2 g / L citric acid; And / or, the production culture medium described in step one includes 20-40 g / L glucose, 3-7 g / L yeast extract, 3-7 g / L peptone, 0.1-0.25 g / L magnesium sulfate, 0.05-0.1 g / L potassium dihydrogen phosphate, and 0.5-1.2 g / L citric acid.

4. The method for preparing bacterial cellulose sutures loaded with aFGF according to claim 2, characterized in that, The process parameters for the shaking culture in step two include: rotation speed set to 150~180 r / min, temperature set to 28~30℃, and shaking culture time set to 36~48 h.

5. The method for preparing bacterial cellulose sutures loaded with aFGF according to claim 2, characterized in that, In step three, add 40-80 mL of Acetobacter xylinum amplification solution and 3-8 mL of anhydrous ethanol to every 1 L of production culture medium. Set the temperature of the bacterial constant temperature incubator to 28-30℃ and set the static culture time to 5-10 days.

6. The method for preparing bacterial cellulose suture loaded with aFGF according to claim 1, characterized in that: The concentration of the aFGF solution is 1~100μg / L, and the soaking time is set to 1~60min.

7. The method for preparing bacterial cellulose suture loaded with aFGF according to claim 1, characterized in that: The strip-shaped component has a width of 1~5mm, a length of 15~25cm, and a thickness of 0.8~1.5mm.

8. The method for preparing bacterial cellulose suture loaded with aFGF according to claim 1, characterized in that: The strip-shaped components are woven in a single spiral, double spiral, or triple braid pattern.

9. A bacterial cellulose suture loaded with aFGF, characterized in that: It is prepared by the preparation method described in any one of claims 1 to 8.

10. The application of aFGF-loaded bacterial cellulose suture prepared by any one of claims 1 to 8 in medical dressings.

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