Preparation method of piezoelectric intelligent suture for tracheal anastomosis

Abstract

The invention discloses a preparation method of a piezoelectric intelligent suture for tracheal anastomosis, and aims to simulate an endogenous electric field of a wound surface and migration and proliferation of cells at an anastomotic stoma through a conductive polymer by transmitting a bioelectricity signal, shorten the healing time of the anastomotic stoma and improve the healing efficiency of the anastomotic stoma. And the healing condition of the anastomotic stoma can be intelligently monitored through current output.

Description

Technical Field

[0001] The invention belongs to the technical field of medical materials, and in particular relates to a method for preparing a piezoelectric intelligent suture for tracheal anastomosis. Background Art

[0002] Tracheal injury caused by trauma, malignant tumors, iatrogenic injury and other factors often develops into irreversible airway stenosis, obstruction, softening and collapse in the late stage, eventually leading to suffocation and death of the patient. Resection of the diseased tissue and end-to-end anastomosis is the current gold standard for treatment, but when the defect exceeds a certain range, the anastomotic tension is high and prone to infection, often causing fatal complications and poor prognosis. Therefore, there is an urgent need for a more ideal surgical suture for tracheal injury anastomosis in clinical practice.

[0003] The smart sutures reported so far are almost all designed to accelerate wound healing by loading drugs or growth factors on the surface for sustained-release therapy. However, growth factor-mediated therapy faces the challenges of being susceptible to contamination, inactivation, and degradation. In addition, other reported smart sutures are mostly used to sense and monitor the recovery of wound sites and lack therapeutic capabilities. In contrast, electrical stimulation (ELS) has been proven to be an effective non-drug treatment strategy. On the one hand, it can activate the natural healing mechanism of endogenous electric fields, promote the movement of ions inside and outside cells, and further induce cell migration and proliferation, accelerating the process of tissue repair. On the other hand, due to the piezoelectric effect, the tension of the anastomosis can be predicted by detecting the local voltage output, thereby evaluating wound healing. Summary of the invention

[0004] The purpose of the present invention is to provide a method for preparing a piezoelectric intelligent suture for tracheal anastomosis.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A first aspect of the present invention provides a method for preparing a piezoelectric intelligent suture for tracheal anastomosis, comprising the following steps:

[0007] In the first step, the preparation method of the two-dimensional transition metal carbonitride MXene ink using water solvent includes the following steps:

[0008] Dissolve LiF in dilute HCl with a concentration of 1 to 20 mol / L (preferably 9 mol / L), stir for 10 to 30 min (preferably 10 min, 20 min, 30 min), slowly add titanium aluminum carbide to the above solution, stir at 30 to 40 ° C (preferably 37 ° C) for 1 to 24 h (preferably 24 h), level the solution, and centrifuge it several times for the first time;

[0009] The mass ratio of LiF to titanium aluminum carbide is 1 to 10:1 (preferably 1.4:1, 1.6:1, 1.9:1); the mass ratio of LiF to HCl is 1:1 to 10 (preferably 1:3.7, 1:4.1, 1:4.7);

[0010] The upper layer solution after centrifugation is purged with nitrogen, ultrasonicated in an ice bath for 0.5 to 1.5 h (preferably 1 h), and centrifuged a second time to obtain a monolayer MXene dispersion with water as a solvent, and the monolayer MXene dispersion is added to water to obtain a two-dimensional transition metal carbonitride MXene ink with a concentration of 1 to 1000 mg / mL (112.5, 125, 137.5 mg / mL) with water as a solvent;

[0011] In the second step, the preparation method of a monolayer MXene dispersion using DMSO as a solvent comprises the following steps:

[0012] Add DMSO to the two-dimensional transition metal carbonitride MXene ink with water solvent, with the volume ratio of the two-dimensional transition metal carbonitride MXene ink with water solvent to DMSO being 1 to 2:1 (preferably 1:1, 1.3:1, 2:1), repeatedly centrifuge at least three times for 0.5 to 2 hours (preferably 1 hour), and centrifuge the solution again to obtain a monolayer MXene dispersion with DMSO as the solvent;

[0013] The third step is to prepare a polypyrrole (PPy) dispersion comprising the following steps:

[0014] Dispersing the dried polypyrrole (PPy) powder in deionized water to a concentration of 0.01 to 0.1 mmol / mL (preferably 0.03 mmol / mL), and ultrasonicating to obtain a polypyrrole (PPy) dispersion;

[0015] The fourth step is to prepare the MXene / Mg fiber, comprising the following steps:

[0016] Dissolve Mg in the monolayer MXene dispersion prepared in the second step with DMSO as solvent, the Mg concentration is 10-500 mg / mL (preferably 240, 300, 360 mg / mL), stir for 1-12 h (preferably 6 h) to obtain a MXene / Mg spinning solution; extract the spinning solution, inject the MXene / Mg spinning solution into an acetic acid aqueous solution with a concentration of 50-70% (preferably 60%), the volume ratio of the MXene / Mg spinning solution to the acetic acid aqueous solution is 1:1, and wind after complete fusion and solidification;

[0017] The fifth step is to prepare the polypyrrole (PPy) coated fiber, comprising the following steps:

[0018] The MXene / Mg fiber prepared in the fourth step is immersed in the polypyrrole (PPy) dispersion prepared in the third step, and the MXene / Mg fiber is immersed in the polypyrrole (PPy) dispersion, and there is no MXene / Mg fiber on the surface, and the fiber is dried. The above steps are repeated at least three times to obtain a polypyrrole (PPy) coated fiber;

[0019] Step 6: The preparation method of the piezoelectric smart suture comprises the following steps:

[0020] At a temperature of 80-100° C. (preferably 90° C.), the polypyrrole (PPy) coated fiber obtained in the fifth step is pulled into a polycaprolactone (PCL) melt (just immerse it), withdrawn, and cooled to obtain a piezoelectric smart suture.

[0021] The first centrifugation condition in the first step is: 3000-4000Rpm (preferably 3000Rpm, 3500Rpm, 4000Rpm) for 1-10min (preferably 5min).

[0022] The second centrifugation condition in the first step is: 3000-4000Rpm (preferably 3000Rpm, 3500Rpm, 4000Rpm) for 1-20min (preferably 15min).

[0023] The conditions for repeated centrifugation in the second step are: 8000-12000 Rpm (preferably 10000 Rpm).

[0024] The conditions for the second centrifugation in the second step are: 3000-4000 Rpm (preferably 3000 Rpm, 3500 Rpm, 4000 Rpm) for 1-20 min (preferably 15, 18, 20 min).

[0025] The ultrasonic conditions in the third step are: ultrasonication at a power of 400-600w (preferably 500w) for 1-5h (preferably 3h).

[0026] The preparation method of polypyrrole (PPy) powder in the third step comprises the following steps:

[0027] Dissolving pyrrole (Py) in cyclohexane, wherein the volume ratio of pyrrole (Py) to cyclohexane is 1 to 3:39 (preferably 1:39, 2:39, 3:39), and freezing for 0.5 to 2 hours (preferably 1 hour) to obtain a pyrrole-cyclohexane mixture;

[0028] FeCl 3 6H 2O was dissolved in deionized water to a concentration of 1-100 mg / mL (preferably 72.2, 80.6, 97.2 mg / mL), and a pyrrole-cyclohexane mixture was added. Pyrrole (Py) and FeCl 3 6H 2 The volume mass ratio of O is 1 mL: 1-5 g (preferably 1 mL: 1.3 g, 1 mL: 1.6 g, 1 mL: 2.9 g), and the polymerization is carried out at 1-2° C. for 24-48 h (preferably 24 h, 36 h, 48 h), filtered to obtain a polypyrrole (PPy) solid, dried, and ground to obtain the polypyrrole (PPy) powder.

[0029] The drying conditions in the third step are: drying at a temperature of 70 to 90° C. (preferably 80° C.) for 1 to 24 hours (preferably 12 hours).

[0030] In the fourth step, the spinning solution is extracted using a syringe equipped with an 18G or 23G needle.

[0031] In the fourth step, the MXene / Mg spinning solution is injected into the acetic acid aqueous solution with a concentration of 50-70% (preferably 60%) at a rate of 0.1-0.3 ml / min (0.2 ml / min).

[0032] In the fifth step, the MXene / Mg fiber prepared in the fourth step is immersed in the polypyrrole (PPy) dispersion prepared in the third step for 0.5 to 2 minutes (preferably 1 minute).

[0033] In the fifth step, the drying conditions are: drying at a temperature of 70 to 90° C. (preferably 80° C.) for 1 to 24 hours (preferably 24 hours).

[0034] The drawing rate in the sixth step is 1-4 m / min (preferably 3 m / min).

[0035] The preparation method of the polycaprolactone (PCL) melt in the sixth step comprises the following steps:

[0036] The polycaprolactone (PCL) particles are placed at a temperature of 40 to 60° C. (preferably 50° C.) and allowed to stand (preferably for 4 hours) to obtain a polycaprolactone (PCL) melt.

[0037] Due to the adoption of the above technical solution, the present invention has the following advantages and beneficial effects:

[0038] The present invention aims to transmit bioelectric signals through conductive polymers, such as Figure 1 and Figure 2It can be seen that: ① The suture has piezoelectric stability and will not be affected by degradation; ② Secondly, as the tension increases, the output electrical energy increases, showing a positive correlation. Simulating the endogenous electric field on the wound surface, the migration and proliferation of cells at the anastomosis: Figure 3 It can be seen that after the addition of electricity, cell migration is accelerated and the anastomotic healing time is shortened (from Figure 3 The results show that the faster the migration, the faster the scratch area shrinks, so the anastomosis heals faster), and the anastomosis healing condition can be intelligently monitored through current output.

[0039] The piezoelectric smart suture prepared by the present invention has dual properties: first, due to the alternating positive and negative electricity of the piezoelectric smart suture composite multilayer structure, the deformation and extrusion at the anastomosis will cause the formation of an endogenous electric field around the suture, forming an endogenous current and promoting cell migration at the wound. Second, due to the current generated by deformation, the piezoelectric smart suture can predict the tension of the anastomosis, thereby realizing intelligent monitoring of the wound healing situation. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a schematic diagram of the evaluation results of the suture current output stability over 14 days.

[0041] Figure 2 This is a schematic diagram of the current output of the suture under different pulling forces.

[0042] Figure 3 This is a schematic diagram of the effect of sutures on the migration of fibroblasts.

[0043] Figure 4 It is a schematic diagram of the composite structure of the suture.

[0044] Figure 5 It is a schematic diagram of the piezoelectric generation mode.

[0045] Figure 6 It is a schematic diagram of the suture intelligent monitoring mode. DETAILED DESCRIPTION

[0046] In order to explain the present invention more clearly, the present invention is further described below in conjunction with preferred embodiments. It should be understood by those skilled in the art that the following specific description is illustrative rather than restrictive, and should not be used to limit the scope of protection of the present invention.

[0047] Example 1

[0048] A method for preparing a piezoelectric intelligent suture for tracheal anastomosis comprises the following steps:

[0049] In the first step, the preparation method of the two-dimensional transition metal carbonitride MXene ink using water solvent includes the following steps:

[0050] Dissolve 2.8g LiF in 40ml 9mol / L dilute HCl and stir magnetically for 10min to ensure that LiF is completely dissolved. Then, add 1.5g titanium aluminum carbide (Ti 3 AlC 2 ) was slowly added to the above solution and magnetically stirred at 37°C for 24 h. The solution after magnetic stirring was leveled and centrifuged at 3000 Rpm for 5 min several times.

[0051] The upper layer solution after centrifugation was transferred to a gas collection bottle, purged with nitrogen, ultrasonicated in an ice bath for 1 hour, and then centrifuged at 3000Rpm for 15 minutes to obtain a monolayer MXene dispersion with water as the solvent. The above 4.5g monolayer MXene dispersion was added to 40mL of water to obtain a two-dimensional transition metal carbonitride MXene ink with water as the solvent.

[0052] In the second step, the preparation method of a monolayer MXene dispersion using DMSO as a solvent comprises the following steps:

[0053] 20 ml of DMSO was added to 40 ml of the two-dimensional transition metal carbonitride MXene ink in water solvent, and the mixture was centrifuged three times at 10000 Rpm for 1 hour to remove H 2 O was replaced with DMSO. The solution was centrifuged at 3000 Rpm for 15 min to obtain 60 mL of a monolayer MXene dispersion with DMSO as the solvent.

[0054] The third step is to prepare a polypyrrole (PPy) dispersion comprising the following steps:

[0055] Dissolve 1 ml of pyrrole (Py) in 39 ml of cyclohexane and freeze for 1 h to obtain a pyrrole-cyclohexane mixture;

[0056] FeCl 3 6H 2 O (2.888 g) was dissolved in 40 ml of deionized water, and 1 ml of a pyrrole-cyclohexane mixture was added. The mixture was polymerized at 1-2° C. for 24 h. The polymerized solution was filtered by pumping to obtain a polypyrrole (PPy) solid.

[0057] The polypyrrole (PPy) solid was dried in an oven at 80°C for 12 h and ground into powder. The polypyrrole (PPy) (1.5 mmol, 0.1 g) powder was dispersed in 50 ml of deionized water and ultrasonicated at 500 W for 3 h to obtain a polypyrrole (PPy) dispersion.

[0058] The fourth step is to prepare the MXene / Mg fiber, comprising the following steps:

[0059] Mg (2.4 g) was dissolved in 10 ml of the monolayer MXene dispersion prepared in the second step with DMSO as solvent, and magnetic stirring was performed for 6 h to obtain 10 ml of MXene / Mg spinning solution. The spinning solution was extracted with a syringe equipped with an 18G needle, and 50 ml of MXene / Mg spinning solution was injected into 50 ml of 60% acetic acid aqueous solution through a syringe pump at a rate of 0.2 ml / min. After complete fusion and solidification, the MXene / Mg fiber was wound on a reel.

[0060] The fifth step is to prepare the polypyrrole (PPy) coated fiber, comprising the following steps:

[0061] The MXene / Mg fiber (2 g) was immersed in the polypyrrole (PPy) dispersion prepared in the third step for 1 minute. The MXene / Mg fiber was immersed in the polypyrrole (PPy) dispersion and there was no MXene / Mg fiber on the surface. Then, the fiber was taken out and dried at 80°C for 24 hours. The above steps were repeated four times to obtain polypyrrole (PPy) coated fiber.

[0062] Step 6: The preparation method of the piezoelectric smart suture comprises the following steps:

[0063] 5 g of polycaprolactone (PCL) particles were placed at 50° C. and allowed to stand for 4 hours to remove moisture, thereby obtaining a polycaprolactone (PCL) melt.

[0064] At a temperature of 90°C, the polypyrrole (PPy) coated fiber was pulled into a polycaprolactone (PCL) melt (immersion is sufficient), and was drawn out from the spinning needle at a tensile rate of 3 m / min and cooled to obtain a piezoelectric smart suture.

[0065] Figure 4 It is a schematic diagram of the composite structure of the suture. As can be seen from the figure, the piezoelectric smart suture has a three-layer concentric structure to generate a potential difference between the layers. The three-layer concentric structure: the inner layer is MXene / Mg fiber, the middle layer is a polypyrrole (PPy) coating formed by a polypyrrole (PPy) dispersion, and the outer layer is a PCL shell formed by polycaprolactone (PCL) particles. Figure 5 This is a schematic diagram of the piezoelectric generation mode. As can be seen from the figure, the outermost and innermost layers are negatively charged, and the middle layer is positively charged, so that current is generated during the squeezing process. Figure 6 This is a schematic diagram of the suture intelligent monitoring mode. The suture generates current due to the wound tension, and an external ammeter is connected to indirectly reflect the size of the wound tension.

[0066] The piezoelectric smart suture prepared by the present invention has dual properties: first, due to the alternating positive and negative electricity of the piezoelectric smart suture composite multilayer structure, the deformation and extrusion at the anastomosis will cause the formation of an endogenous electric field around the suture, forming an endogenous current and promoting cell migration at the wound. Second, due to the current generated by deformation, the piezoelectric smart suture can predict the tension of the anastomosis, thereby realizing intelligent monitoring of the wound healing situation.

[0067] The piezoelectric smart suture prepared by the present invention mainly has the following functions: the end of the piezoelectric smart suture is fixed on a stretching machine, and the stretching machine can adjust different stretching ratios to accurately measure electrical signals under different contraction levels.

[0068] (1) Under the same pulling force in vitro, the suture has piezoelectric output characteristics and remains stable after 14 days, ensuring that the suture can continuously supply power to the wound within 14 days. Figure 1 As shown, Figure 1 It is a schematic diagram of the evaluation results of the suture current output stability over 14 days.

[0069] Specific method: The in vitro electrical output performance of the suture was tested by connecting Keithley6514 and oscilloscope for 14 days. The in vitro experimental process is as follows: The end of the suture is fixed on a stretching machine, which can adjust different stretching ratios to accurately measure the electrical signal at different contraction levels. Then, it is placed in PBS solution and measured through stretch recovery cycles. According to the results, it can be seen that within 14 days, even in a wet state, it can maintain its inherent piezoelectric properties and is not affected.

[0070] (2) Under different pulling forces, the magnitude of the current generated by the suture changes accordingly, thus having the function of real-time monitoring of wound tension; the results are as follows Figure 2 As shown, Figure 2 This is a schematic diagram of the current output of the suture under different pulling forces.

[0071] Specific method: Keithley6514 and oscilloscope were connected to test the in vitro electrical output performance of the suture for 14 days. The in vitro experimental process is as follows: The end of the suture is fixed on a stretching machine, and the stretching machine can adjust different stretching ratios to accurately measure the electrical signals at different contraction levels. According to the results, it can be seen that as the tension increases, the electrical generation performance of the suture increases, and the two are positively correlated, so the tension can be indirectly reflected by the current size.

[0072] (3) Voltage stimulation was shown to promote fibroblast migration and promote tracheal port tissue healing. Figure 3 As shown, Figure 3 This is a schematic diagram of the effect of sutures on the migration of fibroblasts.

[0073] Fibroblasts were cultured in a 6-well cell plate for 48 hours. One end of the suture was stretched to generate electricity, and the other end of the suture was placed at the bottom of the six-well plate containing the fibroblasts for electrical stimulation. Then, a scratch of about 500 μm wide was made on the fibroblasts covering the 6-well cell plate with the tip of a pipette. Electrical treatment was performed once every 12 hours for 1 hour, for a total of 2 treatments, and the area of ​​the scratch area was quantified. It can be seen that the comparison between the powered and blank groups, i.e., no powered group, clearly shows that cell migration is accelerated after power is applied, and the area of ​​the scratch area in the middle is significantly reduced after 24 hours.

[0074] The present invention aims to transmit bioelectric signals through conductive polymers, such as Figure 1 and Figure 2 It can be seen that: ① The suture has piezoelectric stability and will not be affected by degradation; ② Secondly, as the tension increases, the output electrical energy increases, showing a positive correlation. Simulating the endogenous electric field on the wound surface, the migration and proliferation of cells at the anastomosis: Figure 3 It can be seen that after the addition of electricity, cell migration is accelerated and the anastomotic healing time is shortened (from Figure 3 The results show that the faster the migration, the faster the scratch area shrinks, so the anastomosis heals faster), and the anastomosis healing condition can be intelligently monitored through current output.

[0075] Example 2

[0076] A method for preparing a piezoelectric intelligent suture for tracheal anastomosis comprises the following steps:

[0077] In the first step, the preparation method of the two-dimensional transition metal carbonitride MXene ink using water solvent includes the following steps:

[0078] 3.2g LiF was dissolved in 40ml 9mol / L dilute HCl and stirred for 20min to ensure that LiF was completely dissolved. 3 AlC 2 ) was slowly added to the above solution and magnetically stirred at 37°C for 24 hours. The solution after magnetic stirring was leveled and centrifuged at 3500 Rpm for 5 minutes several times. The lower layer of solid after centrifugation was repeatedly washed with deionized water until the pH was about 6.

[0079] The upper layer solution after centrifugation was transferred to a gas collection bottle, purged with nitrogen, ultrasonicated in an ice bath for 1 hour, and then centrifuged at 3500Rpm for 15 minutes to obtain a monolayer MXene dispersion with water as the solvent. The above 5.0g monolayer MXene dispersion was added to 40mL of water to obtain a two-dimensional transition metal carbonitride MXene ink with water as the solvent.

[0080] In the second step, the preparation method of a monolayer MXene dispersion using DMSO as a solvent comprises the following steps:

[0081] 30 ml of DMSO was added to 40 ml of the two-dimensional transition metal carbonitride MXene ink in water solvent, and the mixture was centrifuged three times at 10000 Rpm for 1 hour to remove H 2 O was replaced with DMSO. The solution was centrifuged at 3500 Rpm for 18 min to obtain 70 ml of a monolayer MXene dispersion with DMSO as the solvent.

[0082] The third step is to prepare a polypyrrole (PPy) dispersion comprising the following steps:

[0083] Dissolve 2 ml of pyrrole (Py) in 39 ml of cyclohexane and freeze for 1 h to obtain a pyrrole-cyclohexane mixture;

[0084] FeCl 3 6H 2 O (3.222 g) was dissolved in 40 ml of deionized water, and 1 ml of a pyrrole-cyclohexane mixture was added. The mixture was polymerized at 1-2° C. for 36 h. The polymerized solution was filtered by pumping to obtain a polypyrrole (PPy) solid.

[0085] The polypyrrole (PPy) solid was dried in an oven at 80°C for 12 h and ground into powder. The polypyrrole (PPy) (1.5 mmol, 0.1 g) powder was dispersed in 50 ml of deionized water and ultrasonicated at 500 W for 3 h to obtain a polypyrrole (PPy) dispersion.

[0086] The fourth step is to prepare the MXene / Mg fiber, comprising the following steps:

[0087] Mg (3.0 g) was dissolved in 10 ml of the monolayer MXene dispersion prepared in the second step with DMSO as solvent, and magnetic stirring was performed for 6 h to obtain 10 ml of MXene / Mg spinning solution. The spinning solution was extracted with a syringe equipped with a 23G needle, and 50 ml of MXene / Mg spinning solution was injected into 50 ml of 60% acetic acid aqueous solution at a rate of 0.2 ml / min through a syringe pump. After complete fusion and solidification, the MXene / Mg fiber was wound on a reel.

[0088] The fifth step is to prepare the polypyrrole (PPy) coated fiber, comprising the following steps:

[0089] The MXene / Mg fiber (2.5 g) was immersed in the polypyrrole (PPy) dispersion prepared in the third step for 1 minute. The MXene / Mg fiber was immersed in the polypyrrole (PPy) dispersion and there was no MXene / Mg fiber on the surface. Then it was taken out and dried at 80°C for 24 hours. The above steps were repeated four times to obtain polypyrrole (PPy) coated fiber.

[0090] Step 6: The preparation method of the piezoelectric smart suture comprises the following steps:

[0091] 5 g of polycaprolactone (PCL) particles were placed at 50° C. and allowed to stand for 4 hours to remove moisture, thereby obtaining a polycaprolactone (PCL) melt.

[0092] At a temperature of 90°C, the polypyrrole (PPy) coated fiber was pulled into a polycaprolactone (PCL) melt (immersion is sufficient), and was drawn out from the spinning needle at a tensile rate of 3 m / min and cooled to obtain a piezoelectric smart suture.

[0093] Example 3

[0094] A method for preparing a piezoelectric intelligent suture for tracheal anastomosis comprises the following steps:

[0095] In the first step, the preparation method of the two-dimensional transition metal carbonitride MXene ink using water solvent includes the following steps:

[0096] 3.6g LiF was dissolved in 40ml 9mol / L dilute HCl and stirred for 30min to ensure that LiF was completely dissolved. Then 2.5g titanium aluminum carbide (Ti 3 AlC 2 ) was slowly added to the above solution and magnetically stirred at 37°C for 24 hours. The solution after magnetic stirring was leveled and centrifuged at 4000 Rpm for 5 minutes several times. The lower layer of solid after centrifugation was repeatedly washed with deionized water until the pH was about 6.

[0097] The upper layer solution after centrifugation was transferred to a gas collection bottle, purged with nitrogen, ultrasonicated in an ice bath for 1 hour, and then centrifuged at 4000Rpm for 15 minutes to obtain a monolayer MXene dispersion with water as the solvent. The above 5.5g monolayer MXene dispersion was added to 40mL water to obtain a two-dimensional transition metal carbonitride MXene ink with water as the solvent.

[0098] In the second step, the preparation method of a monolayer MXene dispersion using DMSO as a solvent comprises the following steps:

[0099] 40 ml of DMSO was added to 40 ml of the two-dimensional transition metal carbonitride MXene ink in water solvent, and the mixture was centrifuged three times at 10000 Rpm for 1 hour to remove H 2 O was replaced with DMSO. The solution was centrifuged at 4000 Rpm for 20 min to obtain 80 mL of a monolayer MXene dispersion with DMSO as the solvent.

[0100] The third step is to prepare a polypyrrole (PPy) dispersion comprising the following steps:

[0101] Dissolve 3 ml of pyrrole (Py) in 39 ml of cyclohexane and freeze for 1 h to obtain a pyrrole-cyclohexane mixture;

[0102] FeCl 3 6H 2 O (3.888 g) was dissolved in 40 ml of deionized water, and 1 ml of a pyrrole-cyclohexane mixture was added. The mixture was polymerized at 1-2° C. for 48 h. The polymerized solution was filtered by pumping to obtain a polypyrrole (PPy) solid.

[0103] The polypyrrole (PPy) solid was dried in an oven at 80°C for 12 h and ground into powder. The polypyrrole (PPy) (1.5 mmol, 0.1 g) powder was dispersed in 50 ml of deionized water and ultrasonicated at 500 W for 3 h to obtain a polypyrrole (PPy) dispersion.

[0104] The fourth step is to prepare the MXene / Mg fiber, comprising the following steps:

[0105] Mg (3.6 g) was dissolved in 10 ml of the monolayer MXene dispersion prepared in the second step with DMSO as solvent, and magnetic stirring was performed for 6 h to obtain 10 ml of MXene / Mg spinning solution. The spinning solution was extracted with a syringe equipped with an 18G needle, and 50 ml of MXene / Mg spinning solution was injected into 50 ml of 60% acetic acid aqueous solution at a rate of 0.2 ml / min through a syringe pump. After complete fusion and solidification, the MXene / Mg fiber was wound on a reel.

[0106] The fifth step is to prepare the polypyrrole (PPy) coated fiber, comprising the following steps:

[0107] The MXene / Mg fiber (3 g) was immersed in the polypyrrole (PPy) dispersion prepared in the third step for 1 minute. The MXene / Mg fiber was immersed in the polypyrrole (PPy) dispersion and there was no MXene / Mg fiber on the surface. Then, the fiber was taken out and dried at 80°C for 24 hours. The above steps were repeated four times to obtain polypyrrole (PPy) coated fiber.

[0108] Step 6: The preparation method of the piezoelectric smart suture comprises the following steps:

[0109] 5 g of polycaprolactone (PCL) particles were placed at 50° C. and allowed to stand for 4 hours to remove moisture, thereby obtaining a polycaprolactone (PCL) melt.

[0110] At a temperature of 90°C, the polypyrrole (PPy) coated fiber was pulled into a polycaprolactone (PCL) melt (immersion is sufficient), and was drawn out from the spinning needle at a tensile rate of 3 m / min and cooled to obtain a piezoelectric smart suture.

[0111] Comparative Example 1

[0112] The trachea is sutured with 4-0 monofilament absorbable suture, which is a common type of suture in the prior art. Since the tracheal defect is large, the risk of infection at the anastomosis is high, and the use of the above suture for suturing has the risk of slow healing and a high risk of poor prognosis.

[0113] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment, it is not used to limit the present invention. Any technician familiar with this patent can make some changes or modify the technical contents suggested above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the solution of the present invention.

Claims

1. A method for preparing a piezoelectric intelligent suture for tracheal anastomosis, characterized in that: The following steps are involved: In the first step, the preparation method of the two-dimensional transition metal carbonitride MXene ink using water solvent includes the following steps: Dissolve LiF in dilute HCl with a concentration of 1 to 20 mol / L, stir for 10 to 30 min, slowly add titanium aluminum carbide to the above solution, stir at 30 to 40 ° C for 1 to 24 h, level the solution, and centrifuge it several times for the first time; The mass ratio of LiF to titanium aluminum carbide is 1 to 10:1; the mass ratio of LiF to HCl is 1:1 to 10; The upper layer solution after centrifugation is purged with nitrogen, ultrasonicated in an ice bath for 0.5 to 1.5 hours, and centrifuged a second time to obtain a monolayer MXene dispersion with water as a solvent. The monolayer MXene dispersion is added to water to obtain a two-dimensional transition metal carbonitride MXene ink with a concentration of 1 to 1000 mg / mL in water as a solvent; In the second step, the preparation method of a monolayer MXene dispersion using DMSO as a solvent comprises the following steps: Add DMSO to the two-dimensional transition metal carbonitride MXene ink with water solvent, with the volume ratio of the two-dimensional transition metal carbonitride MXene ink with water solvent to DMSO being 1 to 2:1, repeatedly centrifuge at least three times for 0.5 to 2 hours, and centrifuge the solution again to obtain a monolayer MXene dispersion with DMSO as solvent; The third step, the preparation method of the polypyrrole dispersion comprises the following steps: Dispersing the dried polypyrrole powder in deionized water to a concentration of 0.01 to 0.1 mmol / mL, and ultrasonicating to obtain a polypyrrole dispersion; The fourth step is to prepare the MXene / Mg fiber, comprising the following steps: Dissolve Mg in the monolayer MXene dispersion prepared in the second step with DMSO as solvent, the Mg concentration is 10-500 mg / mL, stir for 1-12 hours to obtain a MXene / Mg spinning solution; extract the spinning solution, inject the MXene / Mg spinning solution into an acetic acid aqueous solution with a concentration of 50-70%, the volume ratio of the MXene / Mg spinning solution to the acetic acid aqueous solution is 1:1, and wind after complete fusion and solidification; The fifth step is to prepare the polypyrrole coated fiber, comprising the following steps: The MXene / Mg fiber prepared in the fourth step is immersed in the polypyrrole dispersion prepared in the third step, and the MXene / Mg fiber is immersed in the polypyrrole dispersion, and there is no MXene / Mg fiber on the surface, and the fiber is dried. The above steps are repeated at least three times to obtain a polypyrrole coated fiber; Step 6: The preparation method of the piezoelectric smart suture comprises the following steps: Under the condition of temperature of 80-100° C., the polypyrrole coated fiber obtained in the fifth step is pulled into the polycaprolactone melt, withdrawn, and cooled to obtain the piezoelectric smart suture.

2. The method for preparing the piezoelectric intelligent suture for tracheal anastomosis according to claim 1, characterized in that: The first centrifugation condition in the first step is: centrifugation at 3000-4000 Rpm for 1-10 min; The second centrifugation condition in the first step is: centrifugation at 3000-4000 Rpm for 1-20 min.

3. The method for preparing the piezoelectric intelligent suture for tracheal anastomosis according to claim 1, characterized in that: The conditions for repeated centrifugation in the second step: 8000-12000 Rpm; The conditions for the second centrifugation in the second step are: centrifugation at 3000-4000 Rpm for 1-20 min.

4. The method for preparing the piezoelectric intelligent suture for tracheal anastomosis according to claim 1, characterized in that: The ultrasonic conditions in the third step are: ultrasonication at a power of 400 to 600 W for 1 to 5 hours.

5. The method for preparing the piezoelectric intelligent suture for tracheal anastomosis according to claim 1, characterized in that: The preparation method of the polypyrrole powder in the third step comprises the following steps: Dissolving pyrrole in cyclohexane, with a volume ratio of pyrrole to cyclohexane of 1 to 3:39, and freezing for 0.5 to 2 hours to obtain a pyrrole-cyclohexane mixture; FeCl3·6H2O is dissolved in deionized water to a concentration of 1-100 mg / mL, a pyrrole-cyclohexane mixture is added, the volume mass ratio of pyrrole to FeCl3·6H2O is 1 mL:1-5 g, polymerization is carried out at 1-2° C. for 24-48 hours, and the polypyrrole solid is obtained by filtering, drying, and grinding to obtain the polypyrrole powder.

6. The method for preparing the piezoelectric intelligent suture for tracheal anastomosis according to claim 5, characterized in that: The drying conditions in the third step are as follows: drying at a temperature of 70 to 90° C. for 1 to 24 hours.

7. The method for preparing the piezoelectric intelligent suture for tracheal anastomosis according to claim 1, characterized in that: In the fourth step, the spinning solution is extracted using a syringe equipped with an 18G or 23G needle; In the fourth step, the MXene / Mg spinning solution is injected into the acetic acid aqueous solution with a concentration of 50-70% at a speed of 0.1-0.3 ml / min.

8. The method for preparing the piezoelectric intelligent suture for tracheal anastomosis according to claim 1, characterized in that: In the fifth step, the MXene / Mg fiber prepared in the fourth step is immersed in the polypyrrole dispersion prepared in the third step for 0.5 to 2 minutes.

9. The method for preparing a piezoelectric intelligent suture for tracheal anastomosis according to claim 1, characterized in that: In the fifth step, the drying conditions are: drying at a temperature of 70 to 90° C. for 1 to 24 hours.

10. The method for preparing a piezoelectric intelligent suture for tracheal anastomosis according to claim 1, characterized in that: The stretching rate in the sixth step is 1 to 4 m / min; The preparation method of the polycaprolactone melt in the sixth step comprises the following steps: The polycaprolactone particles are placed at a temperature of 40 to 60° C. and allowed to stand to obtain a polycaprolactone melt.

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