阅读说明：本技术 一种梯度弹性变形的差别化释药复合敷料及其制备方法 (Gradient elastic deformation differential drug release composite dressing and preparation method thereof ) 是由 高晶 宋子钰 王璐 于 2021-08-20 设计创作，主要内容包括：本发明涉及一种梯度弹性变形的差别化释药复合敷料及其制备方法,包括梯度弹性变形织物和载药水凝胶；将梯度弹性变形织物视为平面结构,所述平面由同心的第III区域、第II区域和第I区域构成；梯度弹性变形织物中的梯度弹性变形是指：第III区域、第II区域和第I区域所对应织物的最大弹性变形率依次减小,且第III区域所对应织物的最大弹性变形率大于关节皮肤最大变形率；第III区域、第II区域和第I区域所对应织物的弹性模量依次增大。载药水凝胶与梯度弹性变形织物结合并位于梯度弹性变形织物的第III区域和第II区域；载药水凝胶的最大弹性变形率大于关节皮肤最大变形率。本发明将水凝胶与织物的复合制得的敷料可根据伤口撕扯程度产生差别化释药效果。(The invention relates to a gradient elastic deformation differential drug release composite dressing and a preparation method thereof, comprising a gradient elastic deformation fabric and a drug-loaded hydrogel; regarding the gradient elastic deformation fabric as a plane structure, wherein the plane is formed by a concentric III region, a concentric II region and a concentric I region; gradient elastic deformation in a gradient elastic deformation fabric means: the maximum elastic deformation rates of the fabrics corresponding to the third area, the second area and the first area are sequentially reduced, and the maximum elastic deformation rate of the fabric corresponding to the third area is larger than the maximum deformation rate of the joint skin; the elastic modulus of the fabrics corresponding to the III area, the II area and the I area is increased in sequence. The drug-loaded hydrogel is combined with the gradient elastic deformation fabric and is positioned in the III region and the II region of the gradient elastic deformation fabric; the maximum elastic deformation rate of the drug-loaded hydrogel is greater than the maximum deformation rate of the joint skin. The dressing prepared by compounding the hydrogel and the fabric can generate differential drug release effect according to the tearing degree of the wound.)

1. A gradient elastic deformation differential drug release composite dressing is characterized in that: comprises gradient elastic deformation fabric and drug-loaded hydrogel;

regarding the gradient elastic deformation fabric as a plane structure, wherein the plane is formed by a concentric III region, a concentric II region and a concentric I region; the area II is formed by taking the edge line of the area III as a starting point and shifting the edge line by D1 outwards, and the inner edge of the area II is collinear with the edge of the area III; the I area is formed by taking the outer edge line of the II area as a starting point and shifting the D2 outwards, and the inner edge of the I area is collinear with the outer edge of the II area;

gradient elastic deformation in a gradient elastic deformation fabric means: the maximum elastic deformation rates of the fabrics corresponding to the third area, the second area and the first area are sequentially reduced, and the maximum elastic deformation rate of the fabric corresponding to the third area is larger than the maximum deformation rate of the joint skin; the elastic modulus of the fabrics corresponding to the third area, the second area and the first area is increased in sequence;

the drug-loaded hydrogel is combined with the gradient elastic deformation fabric and is positioned in the III region and the II region of the gradient elastic deformation fabric; the maximum elastic deformation rate of the drug-loaded hydrogel is greater than the maximum deformation rate of the joint skin.

2. The differential drug release composite dressing with gradient elastic deformation of claim 1, wherein the value of D1 is 1-2 cm, and the value of D2 is 1-2 cm.

3. The differential drug release composite dressing with gradient elastic deformation of claim 1, wherein the maximum elastic deformation rates of the fabrics corresponding to the third zone III, the second zone II and the first zone I are 65-70%, 30-40% and 5-10% in sequence; the elastic modulus of the fabric corresponding to the III area, the II area and the I area is 0.1-0.3 MPa, 0.5-1 MPa and 3-5 MPa in sequence.

4. The gradient elastic deformation differential drug release composite dressing of claim 1, wherein the drug-loaded hydrogel is combined with the gradient elastic deformation fabric, that is, the drug-loaded hydrogel is adhered to the fabric in a whole.

5. The differential drug release composite dressing with gradient elastic deformation of claim 1, wherein the maximum elastic deformation rate of the drug-loaded hydrogel is greater than 60%, the elastic modulus is 0.1-0.3 MPa, and the drug-loading rate is 5-20%.

6. The differential release composite dressing with gradient elastic deformation according to claim 1, wherein the differential release composite dressing is attached to the skin, the hydrogel corresponding to the third area is controlled to be attached to the wound at the center of the joint, and when the joint is repeatedly bent at the maximum angle for 50 times, the cumulative release amount of the drug-loaded hydrogel corresponding to the third area is larger than that of the drug-loaded hydrogel corresponding to the second area.

7. The method for preparing the gradient elastic deformation differential drug release composite dressing according to any one of claims 1 to 6, which is characterized in that: physically crosslinking the drug-loaded hydrogel with the gradient elastic deformation fabric;

the weaving method of the gradient elastic deformation fabric comprises the following steps: determining weaving parameters according to the weave structure of the fabric, the maximum elastic deformation rate of the fabric, the elastic modulus of the fabric and the selected yarns; selecting a computer jacquard flat knitting machine to weave to obtain a gradient elastic deformation fabric;

weaving parameters include cross density and machine density.

8. The method for preparing the gradient elastic deformation differential drug release composite dressing according to claim 7, wherein the preparation process of the drug-loaded hydrogel is as follows:

(1) mixing a 10-20 wt% drug solution with a 1-3 wt% polydopamine solution or cyclodextrin solution in a volume ratio of 3:5, stirring at room temperature for 30-60 minutes, and uniformly stirring to obtain a solution I; the medicine in the medicine solution is more than one of curcumin, ibuprofen, diclofenac and fentanyl;

(2) mixing 0.5-1 wt% of bacterial cellulose nanofiber dispersion liquid with the solution I according to the volume ratio of 3:7 to obtain a mixed solution, stirring at room temperature for 30-90 minutes, adding acrylamide, ammonium persulfate, N-methylene bisacrylamide and tetramethylethylenediamine during stirring, uniformly mixing, and standing the whole system at the temperature of 60 ℃ for 3 hours to obtain a drug-loaded hydrogel;

the adding amounts of the acrylamide, the ammonium persulfate, the N, N-methylene bisacrylamide and the tetramethylethylenediamine respectively account for 20-30 wt%, 05-1 wt%, 0.3-0.6 wt% and 0.1-1 wt% of the solvent in the mixed solution.

9. The method for preparing the gradient elastic deformation differential drug release composite dressing according to claim 7, wherein the physical crosslinking is ultraviolet light irradiation crosslinking, and the specific steps are as follows:

(1) soaking the gradient elastic deformation fabric for 5-15 min by using 0.1-0.3 wt% of ultraviolet initiator solution;

(2) and placing the drug-loaded hydrogel on the area corresponding to the gradient elastic deformation fabric, and irradiating the area for 30-60 min by using ultraviolet light to obtain the differential drug-release composite dressing.

10. The method for preparing the gradient elastic deformation differential drug release composite dressing according to claim 7, wherein the tissue structure of the fabric is as follows: the first area is a weft plain stitch; the second area is 1+1 rib tissues; the III area is 2+2 rib tissues.

Technical Field

The invention belongs to the technical field of biological materials, and relates to a differential drug release composite dressing with gradient elastic deformation and a preparation method thereof.

Background

Skin damage is one of the common diseases of human beings, which not only causes the body function of a patient to be damaged, but also is very easy to be infected by the external environment, and further worsens the wound. Medical dressings are common materials for the treatment of skin lesions. However, conventional wound dressings do not satisfy the basic behavioral requirements of joint parts with frequent movements, such as knees, wrists, shoulders, elbows, and fingers.

At present, the materials used for joint wound parts mainly comprise medical elastic bandages which play a basic role in fixing and protecting joints. However, the medical elastic bandage has no positive treatment effect on the wound, the falling phenomenon can occur when the bandage is not firm, the movement of the patient can be hindered when the bandage is too tight, and the blood circulation of the limb end and the growth of granulation tissues are influenced. Since the medication is applied to the wound site, the bandage needs to be replaced periodically. The existing research data show that by taking a knee joint as an example, the skin deformation degree at the middle point of the knee is maximum when the joint moves, and the deformation rate is 50-60 percent; the skin deformation rate is gradually decreased from the midpoint to the periphery, and the skin deformation rate at the positions 10cm above and below the midpoint of the knee is 5-12%. In rehabilitation therapy, the joint movement angle is about 30-150 degrees to meet the daily life needs. Therefore, in order to treat the joint wound, a new high-end medical dressing which is dynamically attached to the wound and has a positive treatment effect needs to be developed.

Patent CN111575904A discloses a super-elastic waterproof breathable skin dressing with a fold structure and a preparation method thereof, wherein the super-elastic waterproof breathable skin dressing with different fold effects is obtained by adopting an electrostatic spinning technology and controlling the difference of the cross-linking density of two layers of fibers to enable the fibers to shrink to different degrees at different temperatures. The dressing prepared by the invention has the advantages that by introducing the design of the fold structure, the elastic tensile property is greatly improved, and the high ductility matched with the skin at the joint part can be realized. However, the dressing prepared by the patent is prepared by directly adding the medicine into the spinning solution and then carrying out electrostatic spinning, the medicine is uniformly dispersed in the fiber and is released in the wound through diffusion, and the medicine release cannot be controlled according to the stretching degree of the wound, so that the wound can not be treated effectively in time by the medicine.

Therefore, it is very important to design a dressing capable of releasing drug according to the difference of the tearing degree of the wound.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a differential drug release composite dressing with gradient elastic deformation and a preparation method thereof. The fully-formed fabric knitted based on the computerized flat knitting machine has gradient elastic deformation capacity, elastic deformation adaptive to skin deformation during joint movement is achieved through the design of elastic performance of three regions, dynamic fit with joint wounds is achieved, and the hydrogel and the gradient elastic deformation fabric are combined in a cross-linking mode to obtain the differential drug release composite dressing, so that friction of the fabric on the wounds can be prevented, timely and effective controlled release of drugs can be achieved, the drugs can be released timely, pain of a patient caused by pulling of the wounds due to joint movement can be relieved, and the practicability and the use comfort of the dressing are improved.

In order to achieve the purpose, the invention adopts the following scheme:

a gradient elastic deformation differential drug release composite dressing comprises a gradient elastic deformation fabric and a drug-loaded hydrogel;

regarding the gradient elastic deformation fabric as a plane structure, wherein the plane is formed by a concentric III region, a concentric II region and a concentric I region; the area II is formed by taking the edge line of the area III as a starting point and shifting the edge line by D1 outwards, and the inner edge of the area II is collinear with the edge of the area III; the I area is formed by taking the outer edge line of the II area as a starting point and shifting the D2 outwards, and the inner edge of the I area is collinear with the outer edge of the II area;

gradient elastic deformation in a gradient elastic deformation fabric means: the maximum elastic deformation rates of the fabrics corresponding to the III area, the II area and the I area are sequentially reduced, and the maximum elastic deformation rate of the fabric corresponding to the III area is larger than the maximum deformation rate of the joint skin (about 60%); the elastic modulus of the fabrics corresponding to the third area, the second area and the first area is increased in sequence;

the drug-loaded hydrogel is combined with the gradient elastic deformation fabric and is positioned in the III region and the II region of the gradient elastic deformation fabric; the maximum elastic deformation rate of the drug-loaded hydrogel is greater than the maximum deformation rate of the joint skin (about 60%).

Elastic deformation is the phenomenon that the material deforms under the action of external force, and the deformation disappears completely after the external force is removed.

The modulus of elasticity, the stress and strain of a material in the elastic deformation phase are in a proportional relationship, and the proportionality coefficient is called the modulus of elasticity. The elastic modulus can be regarded as an index for measuring the difficulty of the material in elastic deformation, and the larger the value of the elastic modulus, the larger the stress for causing the material to generate certain elastic deformation, that is, the higher the rigidity of the material, that is, the smaller the elastic deformation generated under the action of certain stress.

The method is characterized in that an LRXPLUS universal material testing machine is used for measuring the elastic deformation capacity of the dressing, the width of an experimental sample is 10mm, the effective length of the test is 50mm, the two ends of the experimental sample are respectively reserved with 25mm allowance for clamping, constant-speed extension is adopted, the tensile speed is 100mm/min, after the experiment is finished, a load-extension curve is obtained, and the maximum elastic deformation rate and the elastic modulus are obtained through calculation of the load-extension curve.

The hydrogel is a three-dimensional network substance formed by crosslinking high molecular polymers through covalent bonds, hydrogen bonds or van der waals force and the like, and the substance is soft and elastic. The drug-loaded hydrogel is placed between the skin (wound) and the gradient elastic deformation fabric, so that secondary damage caused by friction of the gradient elastic deformation fabric on the wound can be avoided, and the drug-loaded hydrogel can play an active treatment role by continuously releasing drugs. In particular, the dressing of the present invention has the characteristics of releasing drugs to different degrees according to whether the joint moves or not, and specifically comprises: when the joint is still, namely static, the medicine is slowly released through diffusion to treat the wound; when the joint moves, the hydrogel is stretched and extruded by the skin and the gradient elastic deformation fabric, pores in the hydrogel become small, partial molecular chains are broken, a large amount of medicine is released, and the analgesic effect on the wound is achieved.

Meanwhile, when the joint moves, the skin at the joint deforms, the fabrics corresponding to the III-th area, the II-th area and the I-th area of the gradient elastic deformation fabric elastically deform to different degrees, the larger the deformation amount is, the more obvious the narrowing of the pore structure is, and the relatively more medicine is released, namely, the fabric in the III-th area deforms to the maximum, the generated force drives the hydrogel in the area to deform to the maximum, the narrowing of the pore structure of the hydrogel is obvious, the acting force between the medicine and the hydrogel is obviously weakened, the medicine release speed is high, and the maximum medicine release amount is generated. And because the fabric in the second area is reduced in shape and the generated force is small, the hydrogel compounded in the second area is small in deformation, the change of the pore structure is not obvious, the influence on the acting force between the medicine and the hydrogel is small, the medicine release speed is slow, and the medicine release amount is small. Namely, the gradient elastic deformation differential drug release composite dressing of the invention can release more drug in the main deformation area of the joint (the hydrogel is forced to release drug by large deformation amount), and less drug in the secondary deformation area, thereby achieving the effect of differential drug release according to the tearing degree of the wound.

In addition, the area I on the fabric in the gradient elastic deformation differential drug release composite dressing of the invention is used as the outermost area of the dressing, and the low elastic deformation and the high elastic modulus of the gradient elastic deformation differential drug release composite dressing play roles in fixing the dressing and maintaining the wound stability.

Because the maximum deformation rate of the joint skin is about 60 percent, and the performance and weaving requirements of fiber materials are combined, the elastic deformation and the elastic modulus of the fabric in the area III can meet the maximum deformation rate of the skin, can generate deformation under small stress, and meet the requirement on the deformation degree of the fabric during joint movement. The function of the area II is to form gradient release of the composite hydrogel, avoid the fault phenomenon at the junction of the area III and the area I, and design a transition area according to the deformation degree of the corresponding position of the skin.

As a preferred technical scheme:

according to the differential drug release composite dressing with gradient elastic deformation, the value of D1 is 1-2 cm, the value of D2 is 1-2 cm, and the values of D1 and D2 are set in such a way, so that the dressing can cover joint wounds, obvious gradient elasticity is easy to weave, and raw materials are saved.

According to the differential drug release composite dressing with gradient elastic deformation, the maximum elastic deformation rates of fabrics corresponding to the third area, the second area and the first area are 65-70%, 30-40% and 5-10% in sequence; the elastic modulus of the fabric corresponding to the III area, the II area and the I area is 0.1-0.3 MPa, 0.5-1 MPa and 3-5 MPa in sequence; the reason why the maximum elastic deformation rate and the elastic modulus of the fabric corresponding to each region are set as follows: on the premise of meeting the requirement that the fabric can be actually produced, the elastic deformation rate is set according to the skin deformation rate of the corresponding position, and the fabric covers the surface of the skin, so that the deformation rate is slightly larger than the skin deformation rate in actual stretching. Elasticity modulus is little, and is yielding, and the degree of difficulty that warp in different regions is different, can guarantee that the dressing produces gradient elasticity along with joint motion and changes, central part yielding promptly, can not cause extrusion and constraint to the joint and feel, restricts the patient and moves, and peripheral region is difficult to warp, then can fix the dressing position and stabilize the wound. The intermediate transition region is to avoid fault formation at the junction.

In the differential drug release composite dressing with gradient elastic deformation, the drug-loaded hydrogel is combined with the gradient elastic deformation fabric, namely the drug-loaded hydrogel is integrally adhered to the fabric.

According to the gradient elastic deformation differential drug release composite dressing, the maximum elastic deformation rate of the drug-loaded hydrogel is more than 60%, the elastic modulus is 0.1-0.3 MPa, and the drug-loaded amount (namely the mass percentage of the drug loaded amount in the hydrogel) is 5-20%.

According to the differential drug release composite dressing with gradient elastic deformation, the differential drug release composite dressing is attached to the skin, the hydrogel corresponding to the third area is controlled to be attached to the wound at the center of the joint, when the joint is repeatedly bent for 50 times at the maximum angle, the cumulative drug release amount of the drug-loaded hydrogel corresponding to the third area is larger than that of the drug-loaded hydrogel corresponding to the second area, for example, when the deformation of the skin wound at the center of the joint is 60%, the deformation of the fabric in the third area is 65%, the fabric deformation drives the hydrogel in the third area to generate larger elastic deformation to 60%, the cumulative drug release amount after being repeatedly stretched for 50 times is 10% -20%, the deformation of the fabric in the second area is 30%, the deformation of the hydrogel to 28%, the deformation of the hydrogel is small, the drug release amount is small, and the cumulative drug release amount after being stretched for 50 times is 1% -5%. The differential drug release composite dressing is convenient to use, can strengthen the effective protection of skin wounds, and has mechanical properties capable of meeting the requirement of repeated stretching of joints in actual use.

The invention also provides a preparation method of the gradient elastic deformation differential drug release composite dressing, which comprises the steps of physically crosslinking the drug-loaded hydrogel with the gradient elastic deformation fabric; physical crosslinking polymers are crosslinked using radiation such as light, heat, etc.;

the weaving method of the gradient elastic deformation fabric comprises the following steps: determining weaving parameters according to the weave structure of the fabric, the maximum elastic deformation rate of the fabric, the elastic modulus of the fabric and the selected yarns; selecting a computer jacquard flat knitting machine to weave to obtain a gradient elastic deformation fabric;

weaving parameters include cross density and machine density.

Compared with other technologies, the knitting technology of the computer jacquard flat knitting machine has the advantages of variable working needle number, convenient loop transfer, transverse movement of a needle bed and the like, and the forming knitting can be realized through the technologies of needle retraction and release and the like. Because the gradient elastic deformation fabric is designed in a specific area, the integrated forming of the fabric can be realized by virtue of the advantages of knitting of a computerized flat knitting machine. Compared with the traditional forming technology, the method can realize the design of the fabric in a specific area, has high production efficiency and saves raw materials.

As a preferred technical scheme:

the preparation method of the gradient elastic deformation differential drug release composite dressing comprises the following steps:

(1) mixing 10-20 wt% of a drug solution (a solvent is deionized water) and 1-3 wt% of a polydopamine solution or a cyclodextrin solution in a volume ratio of 3:5, stirring at room temperature for 30-60 minutes, and uniformly stirring to obtain a solution I; the medicine in the medicine solution is more than one of curcumin, ibuprofen, diclofenac and fentanyl;

(2) mixing 0.5-1 wt% of bacterial cellulose nanofiber dispersion liquid (solvent is deionized water) and the solution I in a volume ratio of 3:7 to obtain a mixed solution, stirring at room temperature for 30-90 minutes, adding acrylamide, ammonium persulfate, N-methylene bisacrylamide and tetramethylethylenediamine during stirring, uniformly mixing, and standing the whole system at 60 ℃ for 3 hours to obtain a drug-loaded hydrogel;

the addition amounts of acrylamide, ammonium persulfate, N-methylene-bisacrylamide and tetramethylethylenediamine respectively account for 20-30 wt%, 0.5-1 wt%, 0.3-0.6 wt% and 0.1-1 wt% of the solvent in the mixed solution.

The addition of polydopamine and cyclodextrin can increase the binding sites of the drug and the hydrogel, thereby increasing the drug loading capacity. The addition of the bacterial cellulose nanofibers can enhance the stability of the internal structure of the hydrogel, thereby improving the mechanical properties of the hydrogel.

The preparation method of the gradient elastic deformation differential drug release composite dressing comprises the following specific steps:

(1) soaking the gradient elastic deformation fabric for 5-15 min by using 0.1-0.3 wt% of ultraviolet initiator solution;

(2) and placing the drug-loaded hydrogel on the area corresponding to the gradient elastic deformation fabric, and irradiating the area for 30-60 min by using ultraviolet light to obtain the differential drug-release composite dressing.

The crosslinking mechanism is as follows: in the presence of an ultraviolet light initiator, the surface of the fabric is irradiated by ultraviolet light to be excited to generate a large number of free radicals, and the hydrogel and the free radicals on the surface of the fabric form a hydrogel-fabric complex in a covalent bonding mode. The invention selects the ultraviolet radiation crosslinking method, can accurately compound the prepared hydrogel with the second area and the third area of the fabric, and the compound prepared by the method has the mechanical property equivalent to that of other crosslinking methods, and is time-saving and convenient to operate.

The preparation method of the gradient elastic deformation differential drug release composite dressing comprises the following steps: the first area is a weft plain stitch; the second area is 1+1 rib tissues; the III area is 2+2 rib tissues.

Advantageous effects

(1) According to the deformation characteristics of the skin of the joint, the gradient elastic deformation capacity of the dressing can meet the characteristic that the skin at different positions deforms differently during joint movement, the dynamic combination of the dressing and the skin is achieved, the basic requirements of daily behaviors of wounds at the joints are met, meanwhile, a hydrogel drug loading system is introduced, the pain-relieving and antibacterial treatment effect on the wounds is achieved, the hydrogel is compounded with the gradient elastic deformation fabric, the differential drug release effect according to the tearing degree of the wounds can be further achieved, and the practicability and the use comfort of the dressing are further improved;

(2) according to the preparation method of the gradient elastic deformation differential drug release composite dressing, the gradient elastic deformation fabric is prepared by using the computerized flat knitting machine full-forming technology in the textile field, the required elastic design requirement can be met, the production efficiency is high, and the yield is easy to realize; the hydrogel preparation method is simple and easy to operate; by adopting a physical crosslinking method, the hydrogel can be accurately bonded to a specific position of the fabric, and the bonding strength is high; the preparation method has simple process flow, and the material has stable structure and is easy to store.

Detailed Description

The invention will be further illustrated with reference to specific embodiments. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.

Example 1

A preparation method of gradient elastic deformation differential drug release composite dressing comprises the following steps:

(1) weaving the gradient elastic deformation fabric:

(1.1) designing a fabric structure: regarding the gradient elastic deformation fabric as a plane structure, wherein the plane is formed by a concentric III region, a concentric II region and a concentric I region; the second area is formed by taking the edge line of the third area as a starting point and shifting the edge line outwards by 1cm, and the inner edge of the second area is collinear with the edge of the third area; the first area is formed by taking the outer edge line of the second area as a starting point and shifting outwards by 1cm, and the inner edge of the first area is collinear with the outer edge of the second area;

the weave structure of the fabric is as follows: the first area is a weft plain stitch; the second area is 1+1 rib tissues; the III area is 2+2 rib tissues;

the maximum elastic deformation rates of the fabrics corresponding to the third area, the second area and the first area are 70%, 35% and 5% in sequence;

the elastic modulus of the fabrics corresponding to the III area, the II area and the I area is 0.1MPa, 0.8MPa and 5MPa in sequence;

(1.2) determining parameters of the yarn and parameters of weaving from the weave structure of the fabric, the maximum elastic deformation rate of the fabric and the elastic modulus of the fabric; selecting a computer jacquard flat knitting machine to weave so as to obtain the designed gradient elastic deformation fabric;

wherein, the yarn is: cotton/spandex blended yarn (95/5)20 tex; weaving parameters are as follows: the transverse density and longitudinal density of the third zone are respectively 50 coils/5 cm and 40 coils/5 cm, the transverse density and longitudinal density of the second zone are respectively 70 coils/5 cm and 63 coils/5 cm, and the transverse density and longitudinal density of the first zone are respectively 113 coils/5 cm and 98 coils/5 cm.

(2) The preparation process of the drug-loaded hydrogel comprises the following steps:

(2.1) mixing a 15 wt% drug solution (solvent is deionized water) with a 1 wt% polydopamine solution according to a volume ratio of 3:5, stirring at room temperature for 40 minutes, and uniformly stirring to obtain a solution I; the medicine in the medicine solution is curcumin;

(2.2) mixing 0.5 wt% of bacterial cellulose nanofiber dispersion liquid (solvent is deionized water) with the solution I in a volume ratio of 3:7 to obtain a mixed solution, stirring at room temperature for 60 minutes, adding acrylamide, N-methylene bisacrylamide and tetramethylethylenediamine during stirring, uniformly mixing, and standing the whole system at 60 ℃ for 3 hours to obtain a drug-loaded hydrogel; wherein, the addition amounts of acrylamide, ammonium persulfate, N-methylene-bisacrylamide and tetramethylethylenediamine respectively account for 20 wt%, 0.5 wt%, 0.3 wt% and 0.15 wt% of the solvent in the mixed solution.

The maximum elastic deformation rate of the prepared drug-loaded hydrogel is 65%, the elastic modulus of the drug-loaded hydrogel is 0.1MPa, and the drug-loaded amount is 5%.

(3) The drug-loaded hydrogel is subjected to ultraviolet radiation crosslinking with the gradient elastic deformation fabric as a whole, and is positioned in the III area and the II area of the gradient elastic deformation fabric: the method comprises the following specific steps:

(3.1) soaking the gradient elastic deformation fabric in the step (1) for 8min by using 0.1 wt% of ultraviolet initiator solution; the photoinitiator in the ultraviolet initiator solution is 2-isopropyl thioxanthone, and the solvent is acetone;

(3.2) placing the drug-loaded hydrogel on a region corresponding to the gradient elastic deformation fabric, and irradiating by ultraviolet light for 50min to obtain the differential drug-release composite dressing;

the prepared differential drug release composite dressing comprises gradient elastic deformation fabric and drug-loaded hydrogel; and (3) attaching the differential drug release composite dressing to the skin, controlling the hydrogel corresponding to the III region to be attached to the wound at the center of the joint, and repeatedly stretching the hydrogel for 50 times when the deformation of the skin wound at the center of the joint is 60%, wherein the cumulative drug release amount of the hydrogel corresponding to the III region is 10% and the cumulative drug release amount of the hydrogel corresponding to the II region is 2%.

Example 2

A preparation method of gradient elastic deformation differential drug release composite dressing comprises the following steps:

(1) weaving the gradient elastic deformation fabric:

(1.1) designing a fabric structure: regarding the gradient elastic deformation fabric as a plane structure, wherein the plane is formed by a concentric III region, a concentric II region and a concentric I region; the second area is formed by taking the edge line of the third area as a starting point and shifting the edge line outwards by 2cm, and the inner edge of the second area is collinear with the edge of the third area; the first area is formed by taking the outer edge line of the second area as a starting point and shifting the outer edge line by 2cm, and the inner edge of the first area is collinear with the outer edge of the second area;

the weave structure of the fabric is as follows: the I area is 1+1 rib tissues; the second area is 1+1 rib tissues; the III area is 1+1 rib texture;

the maximum elastic deformation rates of the fabrics corresponding to the third area III, the second area II and the first area I are 67%, 35% and 7% in sequence;

the elastic modulus of the fabrics corresponding to the third area, the second area and the first area is 0.15MPa, 0.8MPa and 3MPa in sequence;

(1.2) determining parameters of the yarn and parameters of weaving from the weave structure of the fabric, the maximum elastic deformation rate of the fabric and the elastic modulus of the fabric; selecting a computer jacquard flat knitting machine to weave so as to obtain the designed gradient elastic deformation fabric;

wherein, the yarn is: acrylic fiber 18.5 tex; weaving parameters are as follows: the transverse density and the longitudinal density of the third zone are respectively 47 coils/5 cm and 45 coils/5 cm, the transverse density and the longitudinal density of the second zone are respectively 70 coils/5 cm and 63 coils/5 cm, and the transverse density and the longitudinal density of the first zone are respectively 102 coils/5 cm and 93 coils/5 cm.

(2) The preparation process of the drug-loaded hydrogel comprises the following steps:

(2.1) mixing a 15 wt% drug solution (the solvent is deionized water) with a 1.5 wt% cyclodextrin solution according to a volume ratio of 3:5, stirring at room temperature for 40 minutes, and uniformly stirring to obtain a solution I; the medicine in the medicine solution is ibuprofen;

(2.2) mixing 0.7 wt% of bacterial cellulose nanofiber dispersion liquid (solvent is deionized water) with the solution I in a volume ratio of 3:7 to obtain a mixed solution, stirring at room temperature for 60 minutes, adding acrylamide, N-methylene bisacrylamide and tetramethylethylenediamine during stirring, uniformly mixing, and standing the whole system at 60 ℃ for 3 hours to obtain a drug-loaded hydrogel; wherein, the addition amounts of acrylamide, ammonium persulfate, N-methylene-bisacrylamide and tetramethylethylenediamine respectively account for 20 wt%, 0.5 wt%, 0.3 wt% and 0.15 wt% of the solvent in the mixed solution.

The maximum elastic deformation rate of the prepared drug-loaded hydrogel is 70%, the elastic modulus of the drug-loaded hydrogel is 0.15MPa, and the drug-loaded amount is 7%.

(3) The drug-loaded hydrogel is subjected to ultraviolet radiation crosslinking with the gradient elastic deformation fabric as a whole, and is positioned in the III area and the II area of the gradient elastic deformation fabric: the method comprises the following specific steps:

(3.1) soaking the gradient elastic deformation fabric in the step (1) for 10min by using 0.1 wt% of ultraviolet initiator solution; the photoinitiator in the ultraviolet initiator solution is benzophenone, and the solvent is methanol;

(3.2) placing the drug-loaded hydrogel on a region corresponding to the gradient elastic deformation fabric, and irradiating by ultraviolet light for 50min to obtain the differential drug-release composite dressing;

the prepared differential drug release composite dressing comprises gradient elastic deformation fabric and drug-loaded hydrogel; and (3) attaching the differential drug release composite dressing to the skin, controlling the hydrogel corresponding to the III region to be attached to the wound at the center of the joint, and repeatedly stretching the hydrogel for 50 times when the deformation of the skin wound at the center of the joint is 60%, wherein the cumulative drug release amount of the hydrogel corresponding to the III region is 12% and the cumulative drug release amount of the hydrogel corresponding to the II region is 3%.

Example 3

A preparation method of gradient elastic deformation differential drug release composite dressing comprises the following steps:

(1) weaving the gradient elastic deformation fabric:

(1.1) designing a fabric structure: regarding the gradient elastic deformation fabric as a plane structure, wherein the plane is formed by a concentric III region, a concentric II region and a concentric I region; the second area is formed by taking the edge line of the third area as a starting point and shifting the edge line outwards by 2cm, and the inner edge of the second area is collinear with the edge of the third area; the first area is formed by taking the outer edge line of the second area as a starting point and shifting outwards by 1.5cm, and the inner edge of the first area is collinear with the outer edge of the second area;

the weave structure of the fabric is as follows: the first area is a weft plain stitch; the second area is 1+1 rib tissues; the III area is 2+2 rib tissues;

the maximum elastic deformation rates of the fabrics corresponding to the third area, the second area and the first area are 70%, 32% and 5% in sequence;

the elastic modulus of the fabrics corresponding to the III area, the II area and the I area is 0.25MPa, 1MPa and 5MPa in sequence;

(1.2) determining parameters of the yarn and parameters of weaving from the weave structure of the fabric, the maximum elastic deformation rate of the fabric and the elastic modulus of the fabric; selecting a computer jacquard flat knitting machine to weave so as to obtain the designed gradient elastic deformation fabric;

wherein, the yarn is: acrylic fiber 18.5 tex; weaving parameters are as follows: the transverse density and the longitudinal density of the third zone are respectively 55 coils/5 cm and 45 coils/5 cm, the transverse density and the longitudinal density of the second zone are respectively 75 coils/5 cm and 65 coils/5 cm, and the transverse density and the longitudinal density of the first zone are respectively 111 coils/5 cm and 103 coils/5 cm.

(2) The preparation process of the drug-loaded hydrogel comprises the following steps:

(2.1) mixing a 20 wt% drug solution (the solvent is deionized water) with a 1 wt% polydopamine solution according to a volume ratio of 3:5, stirring at room temperature for 40 minutes, and uniformly stirring to obtain a solution I; the drug in the drug solution is diclofenac;

(2.2) mixing 1 wt% of bacterial cellulose nanofiber dispersion liquid (solvent is deionized water) with the solution I in a volume ratio of 3:7 to obtain a mixed solution, stirring at room temperature for 60 minutes, adding acrylamide, N-methylene bisacrylamide and tetramethylethylenediamine during stirring, uniformly mixing, and standing the whole system at 60 ℃ for 3 hours to obtain a drug-loaded hydrogel; wherein the addition amounts of acrylamide, ammonium persulfate, N-methylene-bisacrylamide and tetramethylethylenediamine respectively account for 30 wt%, 1 wt%, 0.6 wt% and 1 wt% of the solvent in the mixed solution.

The maximum elastic deformation rate of the prepared drug-loaded hydrogel is 80%, the elastic modulus of the drug-loaded hydrogel is 0.25MPa, and the drug-loaded amount is 20%.

(3) The drug-loaded hydrogel is subjected to ultraviolet radiation crosslinking with the gradient elastic deformation fabric as a whole, and is positioned in the III area and the II area of the gradient elastic deformation fabric: the method comprises the following specific steps:

(3.1) soaking the gradient elastic deformation fabric in the step (1) for 10min by using 0.3 wt% of ultraviolet initiator solution; the photoinitiator in the ultraviolet initiator solution is benzophenone, and the solvent is methanol;

(3.2) placing the drug-loaded hydrogel on a region corresponding to the gradient elastic deformation fabric, and irradiating by ultraviolet light for 50min to obtain the differential drug-release composite dressing;

the prepared differential drug release composite dressing comprises gradient elastic deformation fabric and drug-loaded hydrogel; and (3) attaching the differential drug release composite dressing to the skin, controlling the hydrogel corresponding to the III region to be attached to the wound at the center of the joint, and repeatedly stretching the hydrogel for 50 times when the deformation of the skin wound at the center of the joint is 60%, wherein the cumulative drug release amount of the hydrogel corresponding to the III region is 17% and the cumulative drug release amount of the hydrogel corresponding to the II region is 5%.

Example 4

A preparation method of gradient elastic deformation differential drug release composite dressing comprises the following steps:

(1) weaving the gradient elastic deformation fabric:

(1.1) designing a fabric structure: regarding the gradient elastic deformation fabric as a plane structure, wherein the plane is formed by a concentric III region, a concentric II region and a concentric I region; the second area is formed by taking the edge line of the third area as a starting point and shifting the edge line outwards by 2cm, and the inner edge of the second area is collinear with the edge of the third area; the first area is formed by taking the outer edge line of the second area as a starting point and shifting outwards by 1.5cm, and the inner edge of the first area is collinear with the outer edge of the second area;

the weave structure of the fabric is as follows: the first area is a weft plain stitch; the second area is 1+1 rib tissues; the III area is 2+2 rib tissues;

the maximum elastic deformation rates of the fabrics corresponding to the third area, the second area and the first area are 70%, 35% and 5% in sequence;

the elastic modulus of the fabrics corresponding to the third area, the second area and the first area is 0.15MPa, 0.8MPa and 5MPa in sequence;

(1.2) determining parameters of the yarn and parameters of weaving from the weave structure of the fabric, the maximum elastic deformation rate of the fabric and the elastic modulus of the fabric; selecting a computer jacquard flat knitting machine to weave so as to obtain the designed gradient elastic deformation fabric;

wherein, the yarn is: cotton/spandex blended yarn (95/5)20 tex; weaving parameters are as follows: the transverse density and longitudinal density of the third zone are respectively 50 coils/5 cm and 40 coils/5 cm, the transverse density and longitudinal density of the second zone are respectively 70 coils/5 cm and 63 coils/5 cm, and the transverse density and longitudinal density of the first zone are respectively 113 coils/5 cm and 98 coils/5 cm.

(2) The preparation process of the drug-loaded hydrogel comprises the following steps:

(2.1) mixing a 15 wt% drug solution (the solvent is deionized water) with a 1.5 wt% cyclodextrin solution according to a volume ratio of 3:5, stirring at room temperature for 40 minutes, and uniformly stirring to obtain a solution I; the drug in the drug solution is fentanyl;

(2.2) mixing 0.5 wt% of bacterial cellulose nanofiber dispersion liquid (solvent is deionized water) with the solution I in a volume ratio of 3:7 to obtain a mixed solution, stirring at room temperature for 60 minutes, adding acrylamide, N-methylene bisacrylamide and tetramethylethylenediamine during stirring, uniformly mixing, and standing the whole system at 60 ℃ for 3 hours to obtain a drug-loaded hydrogel; wherein the addition amounts of acrylamide, ammonium persulfate, N-methylene-bisacrylamide and tetramethylethylenediamine respectively account for 30 wt%, 0.8 wt%, 0.5 wt% and 0.25 wt% of the solvent in the mixed solution.

The maximum elastic deformation rate of the prepared drug-loaded hydrogel is 67%, the elastic modulus of the drug-loaded hydrogel is 0.15MPa, and the drug-loaded amount is 10%.

(3) The drug-loaded hydrogel is subjected to ultraviolet radiation crosslinking with the gradient elastic deformation fabric as a whole, and is positioned in the III area and the II area of the gradient elastic deformation fabric: the method comprises the following specific steps:

(3.1) soaking the gradient elastic deformation fabric in the step (1) for 8min by using 0.1 wt% of ultraviolet initiator solution; the photoinitiator in the ultraviolet initiator solution is 2-isopropyl thioxanthone, and the solvent is acetone;

(3.2) placing the drug-loaded hydrogel on a region corresponding to the gradient elastic deformation fabric, and irradiating by ultraviolet light for 50min to obtain the differential drug-release composite dressing;

the prepared differential drug release composite dressing comprises gradient elastic deformation fabric and drug-loaded hydrogel; and (3) attaching the differential drug release composite dressing to the skin, controlling the hydrogel corresponding to the III region to be attached to the wound at the center of the joint, and repeatedly stretching the hydrogel for 50 times when the deformation of the skin wound at the center of the joint is 60%, wherein the cumulative drug release amount of the hydrogel corresponding to the III region is 15% and the cumulative drug release amount of the hydrogel corresponding to the II region is 3%.

Example 5

A preparation method of gradient elastic deformation differential drug release composite dressing comprises the following steps:

(1) weaving the gradient elastic deformation fabric:

(1.1) designing a fabric structure: regarding the gradient elastic deformation fabric as a plane structure, wherein the plane is formed by a concentric III region, a concentric II region and a concentric I region; the second area is formed by taking the edge line of the third area as a starting point and shifting the edge line outwards by 1.5cm, and the inner edge of the second area is collinear with the edge of the third area; the first area is formed by taking the outer edge line of the second area as a starting point and shifting the outer edge line by 2cm, and the inner edge of the first area is collinear with the outer edge of the second area;

the weave structure of the fabric is as follows: the first area is a weft plain stitch; the second area is weft plain stitch; the third area is a weft plain stitch;

the maximum elastic deformation rates of the fabrics corresponding to the third area III, the second area II and the first area I are 65%, 30% and 5% in sequence;

the elastic modulus of the fabrics corresponding to the III area, the II area and the I area is 0.3MPa, 1MPa and 5MPa in sequence;

(1.2) determining parameters of the yarn and parameters of weaving from the weave structure of the fabric, the maximum elastic deformation rate of the fabric and the elastic modulus of the fabric; selecting a computer jacquard flat knitting machine to weave so as to obtain the designed gradient elastic deformation fabric;

wherein, the yarn is: cotton/spandex blended yarn (95/5)20 tex; weaving parameters are as follows: the transverse density and the longitudinal density of the third area are respectively 42 coils/5 cm and 32 coils/5 cm, the transverse density and the longitudinal density of the second area are respectively 80 coils/5 cm and 75 coils/5 cm, and the transverse density and the longitudinal density of the first area are respectively 113 coils/5 cm and 98 coils/5 cm.

(2) The preparation process of the drug-loaded hydrogel comprises the following steps:

(2.1) mixing a 20 wt% drug solution (the solvent is deionized water) with a 1 wt% polydopamine solution according to a volume ratio of 3:5, stirring at room temperature for 40 minutes, and uniformly stirring to obtain a solution I; the medicine in the medicine solution is curcumin;

(2.2) mixing 1 wt% of bacterial cellulose nanofiber dispersion liquid (solvent is deionized water) with the solution I in a volume ratio of 3:7 to obtain a mixed solution, stirring at room temperature for 60 minutes, adding acrylamide, N-methylene bisacrylamide and tetramethylethylenediamine during stirring, uniformly mixing, and standing the whole system at 60 ℃ for 3 hours to obtain a drug-loaded hydrogel; wherein, the addition amounts of acrylamide, ammonium persulfate, N-methylene-bisacrylamide and tetramethylethylenediamine respectively account for 20 wt%, 0.5 wt%, 0.3 wt% and 0.15 wt% of the solvent in the mixed solution.

The maximum elastic deformation rate of the prepared drug-loaded hydrogel is 85%, the elastic modulus of the drug-loaded hydrogel is 0.3MPa, and the drug-loaded amount is 15%.

(3) The drug-loaded hydrogel is subjected to ultraviolet radiation crosslinking with the gradient elastic deformation fabric as a whole, and is positioned in the III area and the II area of the gradient elastic deformation fabric: the method comprises the following specific steps:

(3.1) soaking the gradient elastic deformation fabric in the step (1) for 8min by using 0.1 wt% of ultraviolet initiator solution; the photoinitiator in the ultraviolet initiator solution is 2-isopropyl thioxanthone, and the solvent is acetone;

(3.2) placing the drug-loaded hydrogel on a region corresponding to the gradient elastic deformation fabric, and irradiating by ultraviolet light for 50min to obtain the differential drug-release composite dressing;

the prepared differential drug release composite dressing comprises gradient elastic deformation fabric and drug-loaded hydrogel; and (3) attaching the differential drug release composite dressing to the skin, controlling the hydrogel corresponding to the III region to be attached to the wound at the center of the joint, and repeatedly stretching the hydrogel for 50 times when the deformation of the skin wound at the center of the joint is 60%, wherein the cumulative drug release amount of the hydrogel corresponding to the III region is 13%, and the cumulative drug release amount of the hydrogel corresponding to the II region is 3.5%.

Example 6

A preparation method of gradient elastic deformation differential drug release composite dressing comprises the following steps:

(1) weaving the gradient elastic deformation fabric:

(1.1) designing a fabric structure: regarding the gradient elastic deformation fabric as a plane structure, wherein the plane is formed by a concentric III region, a concentric II region and a concentric I region; the second area is formed by taking the edge line of the third area as a starting point and shifting the edge line outwards by 1.5cm, and the inner edge of the second area is collinear with the edge of the third area; the first area is formed by taking the outer edge line of the second area as a starting point and shifting the outer edge line by 2cm, and the inner edge of the first area is collinear with the outer edge of the second area;

the weave structure of the fabric is as follows: the first area is a weft plain stitch; the second area is 1+1 rib tissues; the III area is 2+2 rib tissues;

the maximum elastic deformation rates of the fabrics corresponding to the third area III, the second area II and the first area I are 67%, 32% and 7% in sequence;

the elastic modulus of the fabrics corresponding to the III area, the II area and the I area is 0.2MPa, 0.8MPa and 5MPa in sequence;

(1.2) determining parameters of the yarn and parameters of weaving from the weave structure of the fabric, the maximum elastic deformation rate of the fabric and the elastic modulus of the fabric; selecting a computer jacquard flat knitting machine to weave so as to obtain the designed gradient elastic deformation fabric;

wherein, the yarn is: acrylic fiber 18.5 tex; weaving parameters are as follows: the transverse density and the longitudinal density of the third zone are respectively 55 coils/5 cm and 45 coils/5 cm, the transverse density and the longitudinal density of the second zone are respectively 70 coils/5 cm and 63 coils/5 cm, and the transverse density and the longitudinal density of the first zone are respectively 111 coils/5 cm and 103 coils/5 cm.

(2) The preparation process of the drug-loaded hydrogel comprises the following steps:

(2.1) mixing a 20 wt% drug solution (the solvent is deionized water) with a 1.5 wt% cyclodextrin solution according to a volume ratio of 3:5, stirring at room temperature for 40 minutes, and uniformly stirring to obtain a solution I; the medicine in the medicine solution is ibuprofen;

(2.2) mixing 0.7 wt% of bacterial cellulose nanofiber dispersion liquid (solvent is deionized water) with the solution I in a volume ratio of 3:7 to obtain a mixed solution, stirring at room temperature for 60 minutes, adding acrylamide, N-methylene bisacrylamide and tetramethylethylenediamine during stirring, uniformly mixing, and standing the whole system at 60 ℃ for 3 hours to obtain a drug-loaded hydrogel; wherein, the addition amounts of acrylamide, ammonium persulfate, N-methylene-bisacrylamide and tetramethylethylenediamine respectively account for 20 wt%, 0.5 wt%, 0.3 wt% and 0.15 wt% of the solvent in the mixed solution.

The maximum elastic deformation rate of the prepared drug-loaded hydrogel is 75%, the elastic modulus of the drug-loaded hydrogel is 0.2MPa, and the drug-loaded amount is 12%.

(3) The drug-loaded hydrogel is subjected to ultraviolet radiation crosslinking with the gradient elastic deformation fabric as a whole, and is positioned in the III area and the II area of the gradient elastic deformation fabric: the method comprises the following specific steps:

(3.1) soaking the gradient elastic deformation fabric in the step (1) for 10min by using 0.1 wt% of ultraviolet initiator solution; the photoinitiator in the ultraviolet initiator solution is benzophenone, and the solvent is methanol;

(3.2) placing the drug-loaded hydrogel on a region corresponding to the gradient elastic deformation fabric, and irradiating by ultraviolet light for 50min to obtain the differential drug-release composite dressing;

the prepared differential drug release composite dressing comprises gradient elastic deformation fabric and drug-loaded hydrogel; and (3) attaching the differential drug release composite dressing to the skin, controlling the hydrogel corresponding to the III region to be attached to the wound at the center of the joint, and repeatedly stretching the hydrogel for 50 times when the deformation of the skin wound at the center of the joint is 60%, wherein the cumulative drug release amount of the hydrogel corresponding to the III region is 12%, and the cumulative drug release amount of the hydrogel corresponding to the II region is 3.5%.