CN114699566B - Preparation method of absorbable ligation clip - Google Patents
Preparation method of absorbable ligation clip Download PDFInfo
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- CN114699566B CN114699566B CN202210367883.4A CN202210367883A CN114699566B CN 114699566 B CN114699566 B CN 114699566B CN 202210367883 A CN202210367883 A CN 202210367883A CN 114699566 B CN114699566 B CN 114699566B
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L31/00—Materials for other surgical articles, e.g. stents, stent-grafts, shunts, surgical drapes, guide wires, materials for adhesion prevention, occluding devices, surgical gloves, tissue fixation devices
- A61L31/04—Macromolecular materials
- A61L31/06—Macromolecular materials obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
- A61B17/12—Surgical instruments, devices or methods, e.g. tourniquets for ligaturing or otherwise compressing tubular parts of the body, e.g. blood vessels, umbilical cord
- A61B17/122—Clamps or clips, e.g. for the umbilical cord
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L31/00—Materials for other surgical articles, e.g. stents, stent-grafts, shunts, surgical drapes, guide wires, materials for adhesion prevention, occluding devices, surgical gloves, tissue fixation devices
- A61L31/14—Materials characterised by their function or physical properties, e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
- A61L31/148—Materials at least partially resorbable by the body
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- Materials For Medical Uses (AREA)
- Injection Moulding Of Plastics Or The Like (AREA)
Abstract
The absorbable ligature clamp consists of one flexible inner layer and one strong and tough outer layer of integral injection structure of lactide, glycolide and polyglycol as the material. Wherein the flexible inner layer copolymer material comprises 40-70% of lactide, 10-50% of glycolide and 10-30% of polyethylene glycol, and the high-hardness and high-toughness outer layer copolymer material comprises 50-90% of lactide, 10-50% of glycolide and 0-10% of polyethylene glycol. The triblock copolymer of lactide, glycolide and polyethylene glycol has a Ubbelohde viscosity of 1.0-5.0. In the copolymer, lactide is used as a base material, glycolide contains hydrophilic groups to provide good hydrophilicity for the copolymer, the polyethylene glycol block can provide hydrophilicity and flexibility for the copolymer, and the absorbable ligature clamp can be degraded completely for less than 12 weeks.
Description
Technical Field
The invention relates to a preparation method of an absorbable ligation clip for clamping and closing blood vessels or tissues, belonging to the field of medical instruments.
Background
At present, in surgical operation, a metal clip or a clip made of non-absorbable material is often adopted for ligating tubular tissues in a human body, so as to play a role in stopping bleeding or sealing. Metal clips, such as titanium clips, are not degraded and absorbed by human bodies, are retained in the bodies for a long time, and can stimulate tissues to generate inflammation; meanwhile, the metal clip can be developed in the X-ray examination, which causes misjudgment of doctors. The clip made of non-absorbable polymer material does not affect the X-ray examination, but is not absorbed in the human body, and causes the stimulation to the tissues. Absorbable hemostatic ligating clips have appeared in the 80's of the 20 th century. Compared with metal clips and non-absorbable polymer clips, the absorbable clips have the advantages of capability of being absorbed by a human body within a certain time range, no long-term foreign body stimulation on human tissues, less complication, no influence on X-ray examination and the like.
The absorbable ligature clamps on the market at present are mainly divided into two types according to the structure, one type is an integral closed clamp, for example, the absorbable clamps produced by the American medical apparatus and instruments limited and the Nakout technologies limited in Sichuan are single-layer absorbable blood vessel ligature clamps, the adopted materials are high molecular weight poly (p-dioxanone), the structure is V-shaped, and the locking hook is arranged at the locking part. The integrated clamp has the advantages of single structure, simple injection molding and processing and strong clamping force; the defects that the integrated clamp is difficult to simultaneously realize the double requirements of softness, no tissue damage and high rigidity, and clamping force is strong; one is a double layer clip with a relatively soft inner layer of low molecular weight polydioxanone material and a more rigid outer layer of polyglycolide, such as an absorbable clip manufactured by Korea medical and Hangzhou san Stone technologies, inc. The double-layer clamp can realize the advantage that the inner layer is softer and has little damage to tissues, but the V-shaped design and the clamping and closing force are not as same as those of an integral clamp, and the injection molding and the assembly are more complicated. In addition, when the vascular clamp is used for closing blood vessels or tissues in a body, the self-healing time of the blood vessels or the tissues is generally 2-3 weeks, so that the ideal ligation clamp can be rapidly degraded in the body after better mechanical properties are kept within 2-3 weeks. However, after the absorbable ligature clamp is implanted into a body, the degradation time is more than 180 days.
The invention is a patent No. CN201210556673.6, which is characterized in that a high molecular copolymer is modified to endow an injection molding material with a balance point of flexibility and clamping force, but the flexibility and the clamping force are opposite, and certain clamping force is inevitably sacrificed when the flexibility is improved. The invention patent number 201711155807.2 discloses a preparation method of a reinforced absorbable ligature clamp, which is characterized in that nano short fibers are added on a base material of the ligature clamp to provide hardness and clamping force of the ligature clamp, but flexibility is sacrificed, and damage to clamped blood vessels or tissues can be caused.
Disclosure of Invention
The invention aims to provide an integrated double-layer absorbable ligation clip which is strong in clipping force, small in damage to blood vessels or tissues and fast in degradation and absorption in vivo.
The invention is realized by adopting the following technical scheme:
a preparation method of an absorbable ligature clamp comprises a flexible inner layer (figure 2) and a strong and tough outer layer (figure 1), wherein the inner layer and the outer layer are of an integral injection molding structure, and injection molding materials of the inner layer and the outer layer are triblock copolymers of lactide, glycolide and polyethylene glycol. Wherein the flexible inner layer copolymer material comprises 40-70% of lactide, 10-50% of glycolide and 10-30% of polyethylene glycol, and the high-hardness and high-toughness outer layer copolymer material comprises 50-90% of lactide, 10-50% of glycolide and 0-10% of polyethylene glycol. The triblock copolymer of lactide, glycolide and polyethylene glycol has a Ubbelohde viscosity of 1.0-5.0. In the copolymer, lactide is used as a substrate material, glycolide contains hydrophilic groups to provide good hydrophilicity for the copolymer, the polyethylene glycol block can provide hydrophilicity and flexibility for the copolymer, and the complete degradation time of the absorbable ligature clamp is less than 12 weeks; the high-hardness and high-toughness outer layer of the ligation clip can provide higher clamping force for the ligation clip, and the inner layer with certain flexibility is in direct contact with blood vessels or tissues, so that the injury to the blood vessels or the tissues during clamping is avoided. The absorbable ligation clip has the advantages of good biocompatibility, controllable degradation time, good clipping performance, small damage to blood vessels or tissues and the like.
Preferably, the triblock copolymer of lactide, glycolide and polyethylene glycol with high hardness and high toughness has a Ubbelohde viscosity of 3.0-5.0;
more preferably, in the triblock copolymer of lactide, glycolide, and polyethylene glycol having high hardness and high toughness, the lactide proportion is 60 to 80%, the glycolide proportion is 20 to 25%, and the polyethylene glycol proportion is 0 to 5%; more preferably, in the triblock copolymer of lactide, glycolide, and polyethylene glycol having high hardness and high toughness, the molecular weight of polyethylene glycol is 10000 to 20000;
preferably, the triblock copolymer of lactide, glycolide and polyethylene glycol with the flexibility characteristic has a Ubbelohde viscosity of 1.0-3.0;
more preferably, in the triblock copolymer of lactide, glycolide and polyethylene glycol with flexibility, the proportion of lactide is 40-60%, the proportion of glycolide is 10-50% and the proportion of polyethylene glycol is 20-30%; more preferably, in the triblock copolymer of lactide, glycolide and polyethylene glycol with flexibility, the molecular weight of polyethylene glycol is 2000-10000;
preferably, when the triblock copolymer of lactide, glycolide and polyethylene glycol is subjected to twin-screw extrusion granulation, the extrusion temperature of the high-hardness and high-toughness triblock copolymer is 170-180 ℃;
preferably, when the triblock copolymer of lactide, glycolide and polyethylene glycol is subjected to double-screw extrusion granulation, the extrusion temperature of the flexible triblock copolymer is 150-160 ℃;
preferably, when the triblock copolymer of lactide, glycolide and polyethylene glycol is subjected to injection molding by a double-color injection molding machine, the three-section injection molding temperature of high-hardness and high-toughness triblock copolymer granules is 185-190 ℃, 180-185 ℃ and 175-180 ℃; the three-section injection molding temperature of the flexible triblock copolymer is 170-175 ℃, 165-170 ℃ and 160-165 ℃;
compared with the prior art, the invention endows the absorbable ligature clamp with different product characteristics of the inner layer and the outer layer through the integrated injection molding technology of the double-color injection molding machine. The inner layer is a flexible triblock copolymer, and when the ligation clip clamps and closes a blood vessel or a tissue, the inner layer with certain flexibility can reduce the damage of the ligation clip to the blood vessel or the tissue; the outer layer of the ligating clip is made of a high-hardness high-toughness triblock copolymer, and the ligating clip can have a larger closing force when used for clamping blood vessels or tissues, so that the clamping effect on the blood vessels or the tissues is improved, and the ligating clip is prevented from shifting or falling off. And the three-block copolymer base materials with the two characteristics are the same, and the combination is firm during injection molding. In addition, glycolide and polyethylene glycol in the inner-layer triblock copolymer and the outer-layer triblock copolymer are hydrophilic blocks, contain a large number of hydrophilic groups, and can accelerate the rapid degradation of the ligation clip. Through an in vitro simulation degradation test and a rabbit implantation test, the absorbable ligature clamp can maintain the mechanical clamping force required for clamping and closing blood vessels or tissues within 4 weeks; the complete degradation time in vivo is less than 12 weeks.
The absorbable ligature clamp disclosed by the invention has the advantages of good biocompatibility, controllable degradation time, good clamping performance, small damage to blood vessels or tissues and the like.
Description of the drawings:
FIG. 1 is a schematic view of an absorbable ligature clip;
fig. 2 is a schematic view of an absorbable ligature clip.
Detailed description of the invention
(1) Preparation of high-hardness high-toughness copolymer
Weighing 72% of lactide, 25% of glycolide and 3% of polyethylene glycol in mass ratio, adding the weighed materials into a three-mouth reaction bottle, and adding a stannous octoate catalyst, wherein the mass ratio of the catalyst is 0.03%. Connecting one end of a three-mouth reaction bottle with a vacuum pump, connecting one end of the three-mouth reaction bottle with a nitrogen bottle, heating to 60 ℃, repeatedly vacuumizing and filling nitrogen for circulation to remove air and moisture in the reaction bottle, then sealing the reaction bottle under vacuum, reacting for 8 hours at 160 ℃ to obtain triblock copolymer coarse bodies of lactide, glycolide and polyethylene glycol, dissolving the triblock copolymer in acetone, repeatedly precipitating and purifying by using ethanol, and drying to obtain the purified high-hardness high-toughness copolymer. The copolymer is dissolved in trichloromethane, and the viscosity of the copolymer is tested by adopting an Ubbelohde viscometer, wherein the preferable viscosity of the copolymer is in a range of 3.5-4.0.
(2) Preparation of copolymers of a certain flexibility
Weighing 45% of lactide, 30% of glycolide and 600025% of polyethylene glycol in mass ratio, adding the weighed materials into a three-mouth reaction bottle, and adding a stannous octoate catalyst, wherein the mass ratio of the catalyst is 0.03%. One end of a three-mouth reaction bottle is connected with a vacuum pump, the other end of the three-mouth reaction bottle is connected with a nitrogen bottle, the three-mouth reaction bottle is heated to 60 ℃, the vacuum pumping and the nitrogen filling are repeatedly carried out for circulation, the air and the moisture in the reaction bottle are removed, then the reaction bottle is sealed under vacuum, the reaction bottle is placed at 150 ℃ for reaction for 8 hours, the triblock copolymer coarse body of the lactide, the glycolide and the polyethylene glycol is prepared, the triblock copolymer is dissolved in acetone, then the ethanol is used for repeated precipitation and purification, and after drying, the purified high-hardness high-toughness copolymer is prepared. The copolymer is dissolved in trichloromethane, and the viscosity of the copolymer is tested by adopting an Ubbelohde viscometer, wherein the preferred viscosity of the copolymer is in a range of 1.5-2.0.
And (3) testing hardness: the two copolymers were separately melt-tabletted and the hardness was measured with a Vickers hardness tester.
High hardness, high toughness triblock copolymer hardness: 95.4HV
Hardness of triblock copolymer of certain flexibility: 58.5HV
(3) Processing of injection molded pellets
And respectively putting the high-hardness high-toughness triblock copolymer and a triblock copolymer with certain flexibility into a double-screw extruder, and carrying out melt extrusion and shearing granulation to obtain the injection molding granules.
The extrusion temperature of the high-hardness and high-toughness triblock copolymer is set to be 175 ℃;
the flexible triblock copolymer extrusion temperature was set at 155 ℃;
(4) two-color injection molding
A reasonably designed double-color injection mold is selected, a corresponding double-color injection molding machine is selected, the two copolymer granules are respectively added into a hopper of the double-color injection molding machine, and proper injection molding parameters are selected for injection molding.
The main injection molding parameters are as follows:
(5) performance detection
Example 2
(1) Preparing a high-hardness high-toughness copolymer: the mass ratio of lactide to glycolide is 70 percent, the mass ratio of glycolide is 25 percent, and the mass ratio of polyethylene glycol is 5 percent
(2) Preparation of a copolymer of certain flexibility: weighing 40% of lactide, 30% of glycolide and 600030% of polyethylene glycol in percentage by mass
(3) Injection molding pellet processing
And respectively putting the high-hardness high-toughness triblock copolymer and the triblock copolymer with certain flexibility into a double-screw extruder, and carrying out melt extrusion and shearing granulation to obtain the injection molding granules.
The extrusion temperature of the high-hardness high-toughness triblock copolymer is set to be 170 ℃;
the flexible triblock copolymer extrusion temperature was set at 150 ℃;
(4) two-color injection molding
A reasonably designed double-color injection mold is selected, a corresponding double-color injection molding machine is selected, the two copolymer granules are respectively added into a hopper of the double-color injection molding machine, and proper injection molding parameters are selected for injection molding.
The main injection molding parameters are as follows:
having described the principles of the present invention, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (6)
1. A preparation method of an absorbable ligature clamp is characterized by comprising the following steps: the absorbable ligature clamp is composed of a flexible inner layer and a strong inner layer
The hard tough outer layer, the inner layer and the outer layer are integrally formed by injection molding through a double-color injection molding machine, and the injection molding materials of the inner layer and the outer layer
All three-block copolymer of lactide, glycolide and polyethylene glycol, and during injection molding, the outer layer is subjected to three-section injection molding
The temperature is 185 to 190 ℃, 180 to 185 ℃, 175 to 180 ℃, and the inner layer three-section injection molding temperature is respectively
170~175℃、165~170℃、160~165℃；
The flexible inner layer copolymer material comprises 40 to 70 percent of lactide, 10 to 50 percent of glycolide and polyethylene glycol
10 to 30 percent of alcohol, 50 to 90 percent of lactide and glycolide
10 to 50 percent of the total weight of the composition, 0 to 10 percent of polyethylene glycol, and triblock of lactide, glycolide and polyethylene glycol
The copolymer has a Ubbelohde viscosity of 1.0 to 5.0, and the molecular weight of the polyethylene glycol in the copolymer is 2000 to 20000.
2. The method of claim 1, wherein the absorbable ligature clip is prepared by: the absorbable ligature clip has complete degradation time less than 12 weeks.
3. The method of claim 1, wherein the method comprises the steps of: the Wechsler hardness range of the flexible layer of the inner layer of the absorbable ligation clip is 40 to 80HV, and the Wechsler hardness of the high-hardness and high-toughness layer of the outer layer is 80 to 200HV.
4. The method of claim 1, wherein the absorbable ligature clip is prepared by: the triblock copolymer of lactide, glycolide and polyethylene glycol is prepared by the following method: weighing lactide, glycolide and polyethylene glycol according to a certain proportion, adding the lactide, glycolide and polyethylene glycol into a three-port reaction bottle, adding an organic tin or zinc oxide catalyst, connecting one end of the three-port reaction bottle with a vacuum pump, connecting one end of the three-port reaction bottle with a nitrogen bottle, heating to 60-70 ℃, repeatedly vacuumizing and filling nitrogen for circulation, removing air and moisture in the reaction bottle, sealing the reaction bottle under vacuum, reacting for 5-8 hours at 140-180 ℃, purifying and drying reactants to obtain a triblock copolymer of the lactide, the glycolide and the polyethylene glycol, adding the triblock copolymer into a double-screw extruder for granulation, wherein the rotation speed of a screw is 50-70r/min, and the extrusion temperature is 150-190 ℃.
5. The method of claim 1, wherein the absorbable ligature clip is prepared by: the integrated injection molding processing steps of the double-color injection molding machine are as follows: designing two pairs of molds, wherein one half of the two pairs of molds are arranged on a fixed mold fixing plate of a double-color mold injection molding machine, namely one side with an injection molding sprue, and the other half of the two pairs of molds are arranged on a movable mold rotating plate, namely one side ejected by the molds, adding high-hardness and high-toughness triblock copolymer granules and flexible triblock copolymer granules into a hopper of the double-color injection molding machine respectively, after the injection molding of the high-hardness and high-toughness triblock copolymer granules is finished, opening a fixed mold and a movable mold under the tension of the injection molding machine, rotating the movable mold 180 degrees, not ejecting the movable mold containing an injection molding product, closing the molds, performing the injection molding of the flexible triblock copolymer granules, after heat preservation and cooling, opening the fixed mold and the movable mold, ejecting the product at the side of the movable mold, namely, preparing the absorbable ligature clamp, wherein the injection molding temperature is 150 to 190 ℃, and the injection pressure is 80 to 130Bar.
6. The absorbable ligature clip of claim 1, prepared by the method of preparing an absorbable ligature clip, wherein the method comprises the steps of: the absorbable ligature clamp consists of a flexible inner layer (2) and a strong and tough outer layer (1), and the inner layer and the outer layer are of an integral injection molding structure.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1282345A (en) * | 1997-10-03 | 2001-01-31 | 麦克罗梅德公司 | Biodegradable low molecular weight triblock poly(lactide-co-glycolide) polyethylene glycol copolymers having reverse thermal gelation properties |
| CN101081310A (en) * | 2006-05-29 | 2007-12-05 | 杭州圣石科技有限公司 | Adsorbable hemostatic ligation clip |
| CN101333295A (en) * | 2007-06-27 | 2008-12-31 | 中国科学院化学研究所 | Biodegradable high molecular nanometer particles, specialty polymer thereof and preparation method thereof |
| AU2010295314A1 (en) * | 2009-09-18 | 2012-04-19 | Btg International Limited | BAB triblock polymers having improved release characteristics |
| CN107778446A (en) * | 2017-10-18 | 2018-03-09 | 圆容生物医药无锡有限公司 | Degradation time is controllable, the adjustable medical degradable polyurethane of elongation at break |
| CN108078911A (en) * | 2017-12-08 | 2018-05-29 | 复旦大学 | Thermotropic hydrogel sustained release veterinary drug injection for animal contraception and preparation method thereof |
| CN113906057A (en) * | 2019-04-12 | 2022-01-07 | 密歇根大学董事会 | Triblock copolymer and nanofiber gelation microspheres comprising same |
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- 2022-04-08 CN CN202210367883.4A patent/CN114699566B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1282345A (en) * | 1997-10-03 | 2001-01-31 | 麦克罗梅德公司 | Biodegradable low molecular weight triblock poly(lactide-co-glycolide) polyethylene glycol copolymers having reverse thermal gelation properties |
| CN101081310A (en) * | 2006-05-29 | 2007-12-05 | 杭州圣石科技有限公司 | Adsorbable hemostatic ligation clip |
| CN101333295A (en) * | 2007-06-27 | 2008-12-31 | 中国科学院化学研究所 | Biodegradable high molecular nanometer particles, specialty polymer thereof and preparation method thereof |
| AU2010295314A1 (en) * | 2009-09-18 | 2012-04-19 | Btg International Limited | BAB triblock polymers having improved release characteristics |
| CN107778446A (en) * | 2017-10-18 | 2018-03-09 | 圆容生物医药无锡有限公司 | Degradation time is controllable, the adjustable medical degradable polyurethane of elongation at break |
| CN108078911A (en) * | 2017-12-08 | 2018-05-29 | 复旦大学 | Thermotropic hydrogel sustained release veterinary drug injection for animal contraception and preparation method thereof |
| CN113906057A (en) * | 2019-04-12 | 2022-01-07 | 密歇根大学董事会 | Triblock copolymer and nanofiber gelation microspheres comprising same |
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