阅读说明：本技术 一种用于软组织填充修复的脱细胞基质微粒产品及其制备方法 (Acellular matrix particle product for soft tissue filling repair and preparation method thereof ) 是由 潘华倩 潘银根 杨中万 吴锋 于 2021-08-16 设计创作，主要内容包括：本发明提供了一种用于软组织填充修复的脱细胞基质微粒产品及其制备方法。该脱细胞基质微粒产品包括如下质量百分比的组分脱细胞基质微粒2.0-10％,助悬剂0.1-5.0％,余量为注射用水；该脱细胞基质微粒是由非交联脱细胞基质微粒、低交联脱细胞基质微粒、高交联脱细胞基质微粒中的一种或者几种混合组成。本发明提供的脱细胞基质微粒产品弹性好、质地柔软、回弹力强,根据其制备工艺可以形成具有不同降解梯度和不同降解时间、空间结构的脱细胞基质微粒产品,适合真皮浅层组织、真皮深层组织、真皮下组织等软组织的填充与修复,具有很好的应用前景。(The invention provides an acellular matrix particle product for soft tissue filling repair and a preparation method thereof. The acellular matrix particle product comprises 2.0-10% of acellular matrix particles, 0.1-5.0% of a suspending agent and the balance of water for injection in percentage by mass; the acellular matrix particles are formed by mixing one or more of non-crosslinked acellular matrix particles, low-crosslinked acellular matrix particles and high-crosslinked acellular matrix particles. The acellular matrix particle product provided by the invention has good elasticity, soft texture and strong resilience, can form acellular matrix particle products with different degradation gradients, different degradation times and spatial structures according to the preparation process, is suitable for filling and repairing soft tissues such as superficial dermis tissue, deep dermis tissue, subdermal tissue and the like, and has good application prospect.)

1. An acellular matrix microparticle product for soft tissue filling repair is characterized by comprising the following components in percentage by mass: 2.0-10% of acellular matrix particles, 0.1-5.0% of suspending agent and the balance of water for injection;

the acellular matrix particles are formed by mixing one or more of non-crosslinked acellular matrix particles, low-crosslinked acellular matrix particles and high-crosslinked acellular matrix particles.

2. The acellular matrix microparticle product according to claim 1, wherein the suspending agent is selected from one or more of hyaluronic acid, carboxymethyl cellulose, hydroxypropyl methyl cellulose, collagen, gelatin.

3. The acellular matrix microparticle product according to claim 2, wherein said acellular matrix microparticle product comprises one of the following suspending agents in mass%: hyaluronic acid 0.1-5.0%, collagen or gelatin 0.5-5.0%, carboxymethyl cellulose and hydroxypropyl methyl cellulose 0.1-5.0%.

4. The acellular matrix microparticle product according to claim 1, wherein the acellular matrix microparticles consist of the following components in mass percent, based on the total mass of the acellular matrix microparticle: 60-80% of non-crosslinked acellular matrix particles and 20-40% of low-crosslinked acellular matrix particles.

5. The acellular matrix microparticle product according to claim 1, wherein the acellular matrix microparticles consist of the following components in mass percent, based on the total mass of the acellular matrix microparticle: 40-60% of non-crosslinked acellular matrix particles, 15-35% of low-crosslinked acellular matrix particles and 15-35% of high-crosslinked acellular matrix particles.

6. The acellular matrix microparticle product according to claim 1, wherein the acellular matrix microparticles consist of the following components in mass percent, based on the total mass of the acellular matrix microparticle: 15-35% of non-crosslinking acellular matrix particles, 15-35% of low-crosslinking acellular matrix particles and 40-60% of high-crosslinking acellular matrix particles.

7. The method of preparing a acellular matrix microparticle product according to any one of claims 1 to 6, comprising the steps of:

step one, homogenizing and granulating at low temperature: starting circulating water for cooling the homogenizing equipment in advance; adding the cut acellular matrix, glacial acetic acid and purified water into a hopper, starting a homogenizing device, and opening a lower discharge valve to collect feed liquid; circulating for 4-6 times according to the requirement; filtering the homogenate by screens with different meshes as required to obtain slurry;

step two, adjusting the pH: adjusting the pH of the slurry to 4.0-8.0 with 1-10% NaOH solution to obtain slurry B, i.e. non-crosslinked acellular matrix particles;

step three, crosslinking: inserting a gas dispersion head into the bottom of the diluted slurry B, opening a gas valve, adjusting the gas flow to be 0.5-2.0 liters/minute, and stirring; adding the cross-linking agent while stirring; continuously introducing gas for 3-6 minutes after the cross-linking agent is added, continuously crosslinking, and cleaning with water for injection after crosslinking is finished to obtain low-crosslinking acellular matrix particles or high-crosslinking acellular matrix particles;

step four, mixing materials: mixing non-crosslinked acellular matrix particles, low-crosslinked acellular matrix particles and/or high-crosslinked acellular matrix particles to obtain the acellular matrix particles;

step five, batching: and uniformly mixing the acellular matrix particles, the suspending agent and water for injection, and freeze-drying, cutting, subpackaging, packaging and sterilizing to obtain the acellular matrix particle product.

8. The method according to claim 7, wherein the mass ratio of the acellular matrix to the glacial acetic acid in the first step is (1.0-5.0): (0.1-0.3).

9. The method of claim 7, wherein the crosslinking is continued for 12 to 24 hours after adding 0.01 to 0.05% of the crosslinking agent in step three so that the degree of crosslinking is 20 to 40% to obtain low-crosslinked acellular matrix microparticles.

10. The method of claim 7, wherein the crosslinking is continued for 4 to 12 hours after adding 0.1 to 0.5% of the crosslinking agent in step three so that the degree of crosslinking is 40 to 60% to obtain highly crosslinked acellular matrix microparticles.

Technical Field

The invention relates to the technical field of biological materials, in particular to an acellular matrix particle product for soft tissue filling and repairing and a preparation method thereof.

Background

The acellular matrix is a tissue material product without immunogenicity or with low immunogenicity formed by removing cells in xenogeneic or xenogeneic tissues from a natural tissue material by a chemical and physical method; since it is derived from natural animal tissues, there are not only individual differences but also differences in different parts of the same individual, and these differences directly affect the performance of use. The acellular matrix is prepared into acellular matrix particles with different grain diameters, so that the bulkiness and three-dimensional space of the material are increased, and the special three-dimensional net structure can attract and gather human tissue cells to reproduce and regenerate on the basis of the acellular matrix, induce tissue growth and achieve the clinical effect of repairing human soft tissue defects. The human soft tissue refers to human skin, subcutaneous tissue, oral soft tissue, fat, muscle, tendon, ligament, fascia, synovial membrane, bursa, nerve, blood vessel, etc., and the texture of these tissues is relatively soft.

The soft tissue filling and repairing material of the acellular matrix particles is applied to the repair of soft tissue defects, such as skin tissue damage repair, the defect repair of oral and maxillofacial soft tissues and the like. The acellular matrix particles obtained by the acellular matrix treatment mainly take type I collagen, have high affinity to cells and excellent biological performance, can induce tissue regeneration, and are used for defect repair of soft tissues of all parts.

The existing conventional crushed acellular matrix particle products are single crosslinking degree or simple non-crosslinking products, have the problems of too fast degradation or too slow degradation, have poor boosting effect, unsmooth smoothness, poor elasticity, hard texture and poor resilience, cannot well meet the requirements of tissue repair and regeneration, and need to develop a product suitable for the requirements of tissue repair and regeneration, such as a product meeting the requirements of filling and repairing of superficial dermal tissues, deep dermal tissues or subdermal tissues on different degradation gradients and different degradation times.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides an acellular matrix particle product for soft tissue filling and repairing, which is suitable for filling and repairing soft tissues such as superficial dermis tissue, deep dermis tissue, subdermal tissue and the like.

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

the invention provides an acellular matrix particle product for soft tissue filling repair, which comprises the following components in percentage by mass: 2.0-10% of acellular matrix particles, 0.1-5.0% of suspending agent and the balance of water for injection;

the acellular matrix particles are formed by mixing one or more of non-crosslinked acellular matrix particles, low-crosslinked acellular matrix particles and high-crosslinked acellular matrix particles.

Further, the suspending agent is selected from one or more of hyaluronic acid, carboxymethyl cellulose, hydroxypropyl methyl cellulose, collagen and gelatin.

Further, the acellular matrix microparticle product comprises one of the following suspending agents in percentage by mass: hyaluronic acid 0.1-5.0%, collagen or gelatin 0.5-5.0%, carboxymethyl cellulose and hydroxypropyl methyl cellulose 0.1-5.0%.

Further, based on the total mass of the acellular matrix particles, the acellular matrix particles are composed of the following components in percentage by mass: 60-80% of non-crosslinked acellular matrix particles and 20-40% of low-crosslinked acellular matrix particles.

Further, based on the total mass of the acellular matrix particles, the acellular matrix particles are composed of the following components in percentage by mass: 40-60% of non-crosslinked acellular matrix particles, 15-35% of low-crosslinked acellular matrix particles and 15-35% of high-crosslinked acellular matrix particles.

Further, based on the total mass of the acellular matrix particles, the acellular matrix particles are composed of the following components in percentage by mass: 15-35% of non-crosslinking acellular matrix particles, 15-35% of low-crosslinking acellular matrix particles and 40-60% of high-crosslinking acellular matrix particles.

The second aspect of the present invention provides a method for preparing the above acellular matrix microparticle product, comprising the steps of:

step one, homogenizing and granulating at low temperature: starting circulating water for cooling the homogenizing equipment in advance; adding the cut acellular matrix, glacial acetic acid and purified water into a hopper, starting a homogenizing device, and opening a lower discharge valve to collect feed liquid; circulating for 4-6 times according to the requirement; filtering the homogenate by screens with different meshes as required to obtain slurry;

step two, adjusting the pH: adjusting the pH of the slurry to 4.0-8.0 with 1-10% NaOH solution to obtain slurry B, i.e. non-crosslinked acellular matrix particles;

step three, crosslinking: inserting a gas dispersion head into the bottom of the diluted slurry B, opening a gas valve, adjusting the gas flow to be 0.5-2.0 liters/minute, and stirring; adding the cross-linking agent while stirring; continuously introducing gas for 3-6 minutes after the cross-linking agent is added, continuously crosslinking, and cleaning with water for injection after crosslinking is finished to obtain low-crosslinking acellular matrix particles or high-crosslinking acellular matrix particles;

step four, mixing materials: mixing non-crosslinked acellular matrix particles, low-crosslinked acellular matrix particles and/or high-crosslinked acellular matrix particles to obtain the acellular matrix particles;

step five, batching: mixing the above acellular matrix microparticles, suspending agent and water for injection, lyophilizing, cutting, packaging, and sterilizing to obtain the final product.

Further, the frequency of the homogenate in the first step is 10-22 Hz.

Further, the mass ratio of the acellular matrix to the glacial acetic acid in the first step is (1.0-5.0): (0.1-0.3).

Further, the gas in the third step is nitrogen or helium.

Further, in the third step, 0.01-0.05% of cross-linking agent is added and then cross-linking is continued for 12-24 hours, so that the cross-linking degree is 20-40%, and the low cross-linked acellular matrix particles are obtained.

Further, in the third step, 0.1-0.5% of cross-linking agent is added and then cross-linking is continued for 4-12 hours so that the cross-linking degree is 40-60% to obtain the high cross-linked acellular matrix particles.

Further, the crosslinking agent is selected from one of glutaraldehyde, formaldehyde, acetaldehyde, 1, 4-butane diglycidyl ether (BDDGE), N-sulfosuccinimidyl-6- (4 '-azido-2' -nitrophenylamino) hexanoate, hexamethylene diisocyanate (HMDC), cyanamide, diphenylphosphoryl azide, and genipin.

Furthermore, the mass of the water for injection used in the washing in the third step is 5-10 times of the mass of the low-crosslinking acellular matrix particles or the high-crosslinking acellular matrix particles, the washing times are 15-20 times, and each washing time is 20-30 minutes.

Further, the sterilization in the fifth step is performed by ethylene oxide sterilization, or Co60 or electron beam irradiation sterilization.

By adopting the technical scheme, compared with the prior art, the invention has the following technical effects:

the acellular matrix microparticle product provided by the invention has the following advantages:

(1) in the cross-linking process, a gas dispersion head with a proper pore diameter is selected, the gas dispersion head is inserted into the bottom of the slurry, a valve for opening gas such as nitrogen or helium is used for regulating the flow, and the mixture is stirred; when the cross-linking agent is added, stirring is carried out while adding, and the buoyancy of the acellular matrix particles is increased by the micro bubbles generated in the process, so that the acellular matrix particle fibers are in a stretched state, and the acellular matrix particles with good elasticity, soft texture and strong resilience are formed;

(2) the soft tissue repairing and reconstructing agent is formed by mixing one or more of non-crosslinking acellular matrix particles, low-crosslinking acellular matrix particles and high-crosslinking acellular matrix particles, can form gradient degradation after mixing, is beneficial to the repair and reconstruction of soft tissues, and can be used for the repair and reconstruction of soft tissues with different requirements.

In conclusion, the acellular matrix particle product provided by the invention has good elasticity, soft texture and strong resilience, can form acellular matrix particle products with different degradation gradients, different degradation times and spatial structures according to the preparation process, and is suitable for filling and repairing soft tissues such as superficial dermal tissues, deep dermal tissues, subdermal tissues and the like.

Drawings

FIG. 1 is a graph of the particle size distribution of an acellular matrix microparticle product made in accordance with one embodiment of the present invention;

FIG. 2 is a scanning electron micrograph of a decellularized matrix microparticle product made in accordance with one embodiment of the invention;

FIG. 3 is a scanning electron micrograph of a decellularized matrix microparticle product made in accordance with one embodiment of the invention;

FIG. 4 is a scanning electron micrograph of a decellularized matrix microparticle product made in accordance with an embodiment of the invention.

Detailed Description

On the basis of the patent with the publication number of CN 103191466B, the invention provides an acellular matrix particle product for soft tissue filling and repairing, and different process parameters are set, so that the prepared product has different degradation gradients, different degradation times and different spatial structures, and is suitable for filling and repairing soft tissues such as superficial dermal tissues, deep dermal tissues, subdermal tissues and the like.

The invention provides an acellular matrix particle product for soft tissue filling repair, which comprises the following components in percentage by mass: 2.0-10% of acellular matrix particles, 0.1-5.0% of suspending agent and the balance of water for injection;

the acellular matrix particles are formed by mixing one or more of non-crosslinked acellular matrix particles, low-crosslinked acellular matrix particles and high-crosslinked acellular matrix particles.

In a preferred embodiment of the present invention, the suspending agent is one or more selected from hyaluronic acid, carboxymethyl cellulose, hydroxypropyl methyl cellulose, collagen, gelatin, etc.

In a preferred embodiment of the present invention, the acellular matrix microparticle product comprises one of the following suspending agents in percentage by mass: hyaluronic acid 0.1-5.0%, collagen or gelatin 0.5-5.0%, carboxymethyl cellulose and hydroxypropyl methyl cellulose 0.1-5.0%.

In a preferred embodiment of the present invention, the acellular matrix particles are composed of the following components in percentage by mass, based on the total mass of the acellular matrix particles: 60-80% of non-crosslinked acellular matrix particles and 20-40% of low-crosslinked acellular matrix particles.

In a preferred embodiment of the present invention, the acellular matrix particles are composed of the following components in percentage by mass, based on the total mass of the acellular matrix particles: 40-60% of non-crosslinked acellular matrix particles, 15-35% of low-crosslinked acellular matrix particles and 15-35% of high-crosslinked acellular matrix particles.

In a preferred embodiment of the present invention, the acellular matrix particles are composed of the following components in percentage by mass, based on the total mass of the acellular matrix particles: 15-35% of non-crosslinking acellular matrix particles, 15-35% of low-crosslinking acellular matrix particles and 40-60% of high-crosslinking acellular matrix particles.

An embodiment of the present invention provides a method for preparing the above acellular matrix microparticle product, comprising the following steps:

step one, homogenizing and granulating at low temperature: starting circulating water for cooling the homogenizing equipment in advance; adding the cut acellular matrix, glacial acetic acid and purified water into a hopper, starting a homogenizing device, and opening a lower discharge valve to collect feed liquid; circulating for 4-6 times according to the requirement; filtering the homogenate by screens with different meshes as required to obtain slurry;

step two, adjusting the pH: adjusting the pH of the slurry to 4.0-8.0 with 1-10% NaOH solution to obtain slurry B, i.e. non-crosslinked acellular matrix particles;

step three, crosslinking: inserting a gas dispersion head into the bottom of the diluted slurry B, opening a gas valve, adjusting the gas flow to be 0.5-2.0 liters/minute, and stirring; adding the cross-linking agent while stirring; continuously introducing gas for 3-6 minutes after the cross-linking agent is added, continuously crosslinking, and cleaning with water for injection after crosslinking is finished to obtain low-crosslinking acellular matrix particles or high-crosslinking acellular matrix particles;

step four, mixing materials: mixing non-crosslinked acellular matrix particles, low-crosslinked acellular matrix particles and/or high-crosslinked acellular matrix particles to obtain the acellular matrix particles;

step five, batching: mixing the above acellular matrix microparticles, suspending agent and water for injection, lyophilizing, cutting, packaging, and sterilizing to obtain the final product.

In a preferred embodiment of the invention, the frequency of homogenization in step one is from 10 to 22 Hz.

In a preferred embodiment of the present invention, the mass ratio of the acellular matrix to the glacial acetic acid in the first step is (1.0-5.0): (0.1-0.3).

In a preferred embodiment of the present invention, the gas in step three is nitrogen or helium.

In a preferred embodiment of the invention, in step three, crosslinking is continued for 12 to 24 hours after adding 0.01 to 0.05 percent of crosslinking agent so that the crosslinking degree is 20 to 40 percent, thereby obtaining low-crosslinked acellular matrix particles.

In a preferred embodiment of the invention, in step three, the crosslinking agent is added to make the final concentration of the crosslinking agent be 0.1-0.5%, and the crosslinking is continued for 4-12 hours to make the crosslinking degree be 40-60%, so as to obtain the high crosslinking acellular matrix particles.

In a preferred embodiment of the invention, the cross-linking agent is selected from one of glutaraldehyde, formaldehyde, acetaldehyde, 1, 4-butane diglycidyl ether (BDDGE), N-sulfosuccinimidyl-6- (4 '-azido-2' -nitrophenylamino) hexanoate, hexamethylene diisocyanate (HMDC), cyanamide, diphenylphosphorylazide, genipin.

In a preferred embodiment of the invention, the water for injection used in the washing in the third step is 5-10 times of the mass of the low-crosslinked acellular matrix particles or the high-crosslinked acellular matrix particles, and the washing times are 15-20 times, and each washing time is 20-30 minutes.

In a preferred embodiment of the invention, the sterilization in step five is performed by ethylene oxide sterilization, or Co60 or electron beam irradiation sterilization.

The present invention will be described in detail and specifically with reference to the following examples and drawings so as to provide a better understanding of the invention, but the following examples do not limit the scope of the invention.

In the examples, the conventional methods were used unless otherwise specified, and reagents used were those conventionally commercially available or formulated according to the conventional methods without specifically specified.

Example 1

This example provides acellular matrix microparticles (non-crosslinked, low crosslinked, and high crosslinked) prepared by a process comprising the steps of:

1. preparation of acellular matrix: an acellular matrix (including an acellular dermal matrix, an acellular peritoneal matrix, an acellular pericardial matrix, an acellular vesicular membrane matrix, etc.) is prepared from animal tissues according to the method disclosed in the invention patent with the publication number of CN 103191466B for preparing human or animal acellular tissues.

2. Preparation of acellular matrix microparticles:

2.1, cutting: shearing the acellular matrix (in a wet state) into small pieces;

2.2 low-temperature homogenization and granulation:

according to the size requirement of the prepared particle size, different technical parameters are selected, and circulating water is started to cool firstly; adding the crushed cell-free matrix of the fragments into a hopper according to the weight of 1.0-5.0% of the cell-free matrix (wet weight), 0.1-0.3% of glacial acetic acid and purified water, starting a homogenizing device, and selecting the frequency of 10-22Hz according to the requirement; opening a lower discharge valve to collect the feed liquid; circulating for 4-6 times according to the requirement; filtering the homogenate by screens with different meshes according to requirements to filter out coarse particles to obtain slurry A;

2.3 adjusting pH: adjusting the pH of the slurry A to 4.0-8.0 by using 1-10% NaOH solution; obtaining slurry B1, namely non-crosslinked acellular matrix particles;

2.4 crosslinking

Diluting the slurry B1 by one time, selecting an air dispersion head, inserting the air dispersion head into the bottom of the slurry, opening a valve for gas such as nitrogen or helium, adjusting the flow rate to be 0.5-2.0L/min, and stirring; simultaneously adding a cross-linking agent (the specific cross-linking agent is shown in the following table 1), and stirring while adding; and after the addition of the cross-linking agent is finished, continuously introducing gas for 3-6 minutes, and closing the gas. Intermediate product A (intermediate products: A2, A3, respectively) was obtained by further crosslinking in the following Table 1

TABLE 1 type of crosslinking agent and parameters of the crosslinking process

Serial number	Name (R)	Crosslinking agent	Concentration of	Crosslinking time (h)	Degree of crosslinking
						A2	Low cross-linked acellular matrix microparticles	Glutaraldehyde	0.01-0.05％	12-24	20-40％
A3	Highly cross-linked acellular matrix microparticles	Glutaraldehyde	0.1-0.5％	4-12	40-60％

Note: the degree of crosslinking is determined by the trinitrophenylhydrazine method.

2.5 cleaning

The intermediate product A2 or A3 is washed 15-20 times (by mass) with 5-10 times of water for injection, and each time for 20-30 minutes. After the washing is finished, the mixture is properly drained to obtain an intermediate product B2: low cross-linked acellular matrix microparticles, or B3: highly cross-linked acellular matrix microparticles.

2.6 determination of solid content

Taking the intermediate product B1 or B2 or B3, and carrying out solid content determination.

Example 2

The embodiment provides an acellular matrix particle product for filling and repairing dermal superficial tissues, which comprises 3.5% of acellular matrix particles, 0.5% of a suspending agent and the balance of water for injection;

based on the total mass of the acellular matrix particles, the acellular matrix particles comprise the following components in percentage by mass: b170% and B230%.

The preparation method of the acellular matrix microparticle product comprises the following steps:

step one, weighing intermediate products B1 and B2 according to the mass percentage, and uniformly mixing to obtain an intermediate product C1;

step two, weighing the intermediate product C1, the suspending agent and water according to the mass percentage, and uniformly mixing to obtain an intermediate product D1;

step three, freeze-drying: pouring the intermediate product D1 into a freeze-drying tray, and freeze-drying in a freeze dryer to obtain an intermediate product E1;

step four, cutting, subpackaging and packaging: cutting the intermediate product E1 into appropriate granules, filling into an injector according to the filling requirement, and putting the injector filled with the intermediate product E1 into a packaging box to obtain a product to be sterilized;

step five, sterilization: selecting ethylene oxide for sterilization to obtain a final product; the product has a particle size distribution as shown in FIG. 1 and a scanning electron microscope as shown in FIG. 2, and is in the form of dispersed collagen fiber bundle with a diameter below 500 nm.

Example 3

The embodiment provides an acellular matrix particle product for filling and repairing deep dermal tissues, which comprises 6.5% of acellular matrix particles, 3.5% of collagen and the balance of water for injection;

based on the total mass of the acellular matrix particles, the acellular matrix particles comprise the following components in percentage by mass: b150%, B225% and B325%.

The preparation method of the acellular matrix microparticle product comprises the following steps:

step one, weighing intermediate products B1, B2 and B3 according to the mass percentage, and uniformly mixing to obtain an intermediate product C2;

step two, weighing the intermediate product C2, the suspending agent and water according to the mass percentage, and uniformly mixing to obtain an intermediate product D2;

step three, freeze-drying: pouring the intermediate product D2 into a freeze-drying tray, and freeze-drying in a freeze dryer to obtain an intermediate product E2;

step four, cutting, subpackaging and packaging: cutting the intermediate product E2 into appropriate granules, filling into an injector according to the filling requirement, and putting the injector filled with the intermediate product E2 into a packaging box to obtain a product to be sterilized;

step five, sterilization: selecting Co60 or electron beam irradiation for sterilization to obtain a final product; the scanning electron micrograph of the product is shown in FIG. 3, and the product is in the form of dispersed collagen fiber bundles, and the diameter of the fiber bundles is generally below 500 nm.

Example 4

The embodiment provides an acellular matrix particle product for filling and repairing hypodermal tissues, which comprises 8.5% of acellular matrix particles, 1.0% of a suspending agent and the balance of water for injection;

based on the total mass of the acellular matrix particles, the acellular matrix particles comprise the following components in percentage by mass: b125%, B225% and B350%.

The preparation method of the acellular matrix microparticle product comprises the following steps:

step one, weighing and uniformly mixing intermediate products B1, B2 and B3 according to the mass percentage to obtain an intermediate product C3;

step two, weighing the intermediate product C3, the suspending agent and water according to the mass percentage, and uniformly mixing to obtain an intermediate product D3;

step three, freeze-drying: pouring the intermediate product D3 into a freeze-drying tray, and freeze-drying in a freeze dryer to obtain an intermediate product E3;

step four, cutting, subpackaging and packaging: cutting the intermediate product E3 into appropriate granules, filling into an injector according to the filling requirement, and putting the injector filled with the intermediate product E3 into a packaging box to obtain a product to be sterilized;

step five, sterilization: selecting ethylene oxide for sterilization to obtain a final product; the scanning electron micrograph of the product is shown in FIG. 4, and the product is in the form of dispersed collagen fiber bundles, and the diameter of the fiber bundles is generally below 500 nm.

Verification examples

1. In vitro degradation test

Each of the samples of examples was taken in the form of 50mg blocks, soaked in pure water, and all air was removed. Excess water was removed with filter paper and the soaked sample was placed in a 150ml triangular flask with a stopper. The bottle had been filled with 100ml of a 1.0% by mass solution of pepsin (activity about 3000U/mg) in hydrochloric acid (0.1 mol/L). Digestion was carried out at 37 ℃. + -. 1 ℃ until complete digestion and the time was recorded. Triplicates were made and the average of three complete digestion times was calculated, the results are given in table 1 below.

2. Rat implant degradation test

The sample was cut into 1cm × 1cm in size and sterilized. Anaesthetizing selected SD rats, removing back hair, disinfecting with iodine, incising skin along the spinal column by operation, wherein the incision is about 5cm long, separating hypodermal tissue to form a capsule cavity, after sufficient hemostasis, selecting 2 implantation points at equal distance of about 2cm on two sides of the spinal column of the rats respectively, implanting samples subcutaneously, separating hypodermal tissue and fascia, suturing a suture line and the hypodermal fascia, finally suturing the back skin, and disinfecting the wound with iodine. Each rat was injected with penicillin 50000U/(kg d) 3d consecutively after the experiment to prevent infection. After surgery, 4 rats were taken at 2, 4, 6, 8, 10, 20, 22, 24, 26, and 28 weeks, sacrificed by dislocation of cervical vertebrae, and the subcutaneous fascia was separated from the material as much as possible, and the absorption of the material was observed, and the results are shown in table 2 below.

TABLE 2 degradation time of the acellular matrix microparticle products provided in the examples

Product(s)	Example 2	Example 3	Example 4
				In vitro enzyme resistance (Pepsin) (hour)	12.3±2.7	32.2±4.5	72.1±6.4
Degradation time for rat implantation (Tian)	28±1.8	56±3.5	182±5.3

The embodiments of the present invention have been described in detail, but the embodiments are merely examples, and the present invention is not limited to the embodiments described above. It will be appreciated by those skilled in the art that any equivalent modifications and substitutions are within the scope of the present invention. Accordingly, equivalent changes and modifications made without departing from the spirit and scope of the present invention should be covered by the present invention.