Drug sustained-release cartilage scaffold
By designing a porous cartilage scaffold with a V-shaped connector, the problem of instability in existing scaffolds was solved, achieving self-fixation and sustained drug release, enhancing post-implantation stability and tissue integration, and promoting the repair of cartilage defects.
Patent Information
- Application Number
- CN202520470635.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-18
- Publication Date
- 2026-01-23
- Estimated Expiration
- 2035-03-18
AI Technical Summary
Existing porous cartilage scaffolds are unstable after implantation, easily loosening and shifting, affecting the repair effect of cartilage defects, and traditional scaffolds lack a fixed structure on their surface.
A self-fixing, sustained-release drug-eluting cartilage scaffold is designed. A porous scaffold is constructed using V-shaped connectors. The scaffold is compressible and resilient, and triangular protrusions or grooves are formed on its surface to fit surrounding tissues. The scaffold material is made of polyurethane and is loaded with drug molecules.
The scaffold achieves self-fixation after implantation, preventing loosening and displacement, enhancing implant stability, and promotes tissue integration through its three-dimensional porous structure, thereby improving the repair effect of cartilage defects.
Smart Images
Figure CN223817706U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of medical device technology, and in particular to a sustained-release drug cartilage scaffold. Background Technology
[0002] Repairing and reconstructing the function of cartilage defects caused by trauma has always been a major challenge in orthopedic clinical practice. If not effectively repaired, the rate of disability and deformity is very high, severely impacting patients' postoperative quality of life. Cartilage defects involve the disruption of the structural integrity of bone tissue, creating large gaps between cartilage tissues. Cartilage repair scaffolds are widely used clinically as an important means of filling cartilage defects. Traditional cartilage filling materials are either hard materials with high mechanical strength or hydrogel materials with low mechanical strength. After implantation, the filling material is not firmly fixed to the surrounding cartilage tissue, and the implant loosens at the cartilage defect site, easily leading to loosening and displacement after surgery, severely affecting the cartilage defect repair effect. Performing a second surgery to re-implant the filling material would bring enormous pain to the patient and a significant socioeconomic burden.
[0003] In recent years, porous cartilage implant scaffolds have been proven to have good osteoconductive properties, endowing the material with the activity of inducing tissue regeneration. Surrounding cells grow into the scaffold through adhesion, migration, proliferation, and differentiation, crawling to replace and form tissue, ultimately assisting in the repair of cartilage defects. Polymer-based porous cartilage implant scaffolds can be compressed to a certain extent. Based on the good elastic deformation of polymers, the porous cartilage scaffold can be compressed and implanted into the defect site. Then, the scaffold rebounds and provides some support with the surrounding tissue, enhancing stability. However, the existing porous cartilage scaffold structure is not conducive to compression and rebound, and the scaffold surface lacks a structure that can fix it to the surrounding tissue. Therefore, inventing a self-fixing porous sustained-release drug cartilage implant scaffold can effectively solve clinical problems such as post-implantation instability. Summary of the Invention
[0004] The technical problem to be solved by this utility model is to provide a sustained-release drug cartilage scaffold in response to the shortcomings of the prior art. The scaffold is a self-fixing cartilage implant scaffold, especially a porous sustained-release drug cartilage implant scaffold with compressible rebound properties.
[0005] To address the aforementioned technical problems, this utility model discloses a sustained-release drug-eluting cartilage scaffold, the specific technical solution of which is as follows:
[0006] A sustained-release drug cartilage scaffold includes several support units stacked sequentially; each support unit includes two polygonal structures, which are three-dimensionally connected by several parallel V-shaped connectors.
[0007] The polygonal structure is formed by connecting two sets of parallel V-shaped connectors end to end;
[0008] The V-shaped connection is formed by connecting two connecting segments through a line connection.
[0009] Preferably, the two polygonal structures are three-dimensionally connected to four parallel V-shaped connectors through their network connection points to form the support unit; the network connection points are the beginning and end ends of the V-shaped connectors.
[0010] The sustained-release drug cartilage scaffold described herein has a three-dimensional porous structure.
[0011] In the V-shaped connecting part, the connecting segment is cylindrical with a length of 0.1~5 mm and a diameter of 0.1~2 mm; preferably, the length is 0.1~0.3 mm and the diameter is 0.2~0.3 mm.
[0012] In the V-shaped connecting part, the included angle between the two connecting segments is an obtuse angle (greater than 90 degrees and less than 180 degrees), preferably 110 to 150 degrees.
[0013] As can be seen from the above connection relationship, each V-shaped connection part is only connected to each other through the network connection point, and the line connection point is not connected to other V-shaped units.
[0014] When the three-dimensional porous support formed by the above connection method is compressed, because the direction of the force on the lines is not perpendicular, the two short lines can bend towards the middle, thereby achieving a certain degree of compression.
[0015] The porosity of the sustained-release drug cartilage scaffold is 50-85%, preferably 60-70%. This porosity can be achieved by adjusting the length and diameter of the connecting segments. The void ratio is the percentage of the volume of pores within the material relative to the total volume of the material.
[0016] The sustained-release drug cartilage scaffold, wherein the V-shaped connecting portion is loaded with drug molecules, specifically consisting of two connecting segments loaded with drug molecules.
[0017] The material of the sustained-release drug cartilage scaffold includes polyurethane.
[0018] Beneficial effects:
[0019] Compared with existing technologies, this invention addresses the problem of unstable implantation of cartilage defect fillers by designing a porous scaffold based on a V-shaped connector. This scaffold can be compressed during implantation and rebounds afterward, providing mechanical support. Simultaneously, the porous scaffold constructed with the V-shaped connector has triangular protrusions or grooves on its surface, which facilitates integration with surrounding tissues. The combined effect of this sustained-release drug-eluting cartilage scaffold achieves self-fixation and stable filling after implantation. Attached Figure Description
[0020] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, and the advantages of the present invention in the above and / or other aspects will become clearer.
[0021] Figure 1 A three-dimensional structural diagram of the sustained-release drug cartilage scaffold provided by this utility model.
[0022] Figure 2 This is a schematic diagram of the support unit of the sustained-release drug cartilage scaffold provided by this utility model.
[0023] Figure 3 A schematic diagram of the single-layer mesh structure of the sustained-release drug cartilage scaffold provided by this utility model.
[0024] Figure 4 Stress-strain curves of the sustained-release drug cartilage scaffold provided by this invention and the control group linear scaffold.
[0025] Figure 5 Compression recovery rate diagram of the sustained-release drug cartilage scaffold provided by this utility model and the linear scaffold of the control group.
[0026] Explanation of reference numerals in the attached drawings: 1-main body of the support frame, 2-line connection, 3-network connection, 4-connecting segment, 101-support unit, 102-polygonal structure, 103-V-shaped connection, 104-single-layer mesh. Detailed Implementation
[0027] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be noted that the embodiments described below are intended to facilitate understanding of the present invention and are not intended to limit it in any way. The advantages and features of the present invention will become clearer from the following description and claims. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.
[0028] Example 1: Sustained-release drug-eluting cartilage scaffold
[0029] The sustained-release drug cartilage scaffold structure provided in this embodiment is as follows: Figure 1 As shown.
[0030] Depend on Figure 1 As can be seen, the aforementioned sustained-release drug-eluting cartilage scaffold includes several support units 101 (such as... Figure 2 As shown, the support unit 101 includes two polygonal structures 102, which are three-dimensionally connected by several parallel V-shaped connecting parts 103.
[0031] The polygonal structure 102 is formed by connecting two sets of parallel V-shaped connectors 103 end to end; as shown Figure 3 As shown, the polygonal structures 102 are sequentially overlapped to form a single-layer mesh structure 104. All line connections 2 and network connections 3 of the single-layer mesh structure 104 are located on the same plane.
[0032] The V-shaped connecting part 103 is formed by two connecting segments 4 connected by a line connection 2.
[0033] Two polygonal structures 102 are three-dimensionally connected by their network connection points 3 and 4 parallel V-shaped connectors 103.
[0034] The network connection point 3 is the first and last ends of the V-shaped connection part 103.
[0035] The sustained-release drug cartilage scaffold described herein has a three-dimensional porous structure.
[0036] The connecting segment 4 is cylindrical, with a length of 0.1~5 mm and a diameter of 0.1~2 mm; in the V-shaped connecting part 103, the included angle between the two connecting segments 4 is an obtuse angle (greater than 90 degrees and less than 180 degrees). From the above connection relationship, it can be seen that each V-shaped connecting part 103 is only interconnected through the network connection point 3, and the line connection point 2 does not connect to other V-shaped units.
[0037] In the sustained-release drug cartilage scaffold, drug molecules are loaded by connecting segment 4.
[0038] Example 2: Preparation of a sustained-release drug-eluting cartilage scaffold
[0039] (1) A sustained-release drug-eluting cartilage scaffold was prepared using low-temperature 3D printing technology with polyurethane polymer as the raw material. The organic solvent was a mixture of 1,4-dioxane and dimethyl sulfoxide, with a preferred volume ratio of 5:1, until the shape memory polyurethane was completely dissolved in the mixed solvent. Drugs that promote cartilage repair (such as wedelia lactone, naringin, baicalin, icariin, theaflavins, curcumin, etc.) were added. In this embodiment, the drug added was wedelia lactone, with a mass fraction of 2% compared to the polyurethane, to obtain the printing precursor solution.
[0040] (2) The printing precursor liquid is used to obtain a scaffold preform through 3D printing. Specifically, the 3D printing equipment is a low-temperature rapid prototyping (LT-RP) printer, the printing speed can be set to 0.1 mm / s~1.5 mm / s, and the temperature of the printing nozzle can be set to 10~20℃. The forming chamber temperature is -25℃. In a preferred embodiment, the printing speed is 0.2 mm / s and the temperature of the printing nozzle is 12℃. The preform is printed line by line and layer by layer according to the pre-designed V-shaped line path (the specific structure is shown in Example 1) to form a three-dimensional porous scaffold preform. The overall size of the scaffold is a 2*2*2cm cube. The length of the connecting segment 4 is 0.2 mm and the diameter is 0.25 mm. The included angle between the connecting segments of the V-shaped units is 120°.
[0041] (3) The porous scaffold embryo is freeze-dried to obtain the sustained-release drug cartilage scaffold. The freeze-drying temperature is -80℃ to -70℃ and the time is 48 to 72 hours.
[0042] Example 3
[0043] This invention also prepared a linear sustained-release drug stent as a control. The preparation method was basically the same as that described in Example 2, except that the V-shaped line paths involved in Example 2 were all replaced with linear line paths during the preparation process.
[0044] Example 4: Compression Rebound of Sustained-Release Drug-Induced Cartilage Scaffold
[0045] The sustained-release drug-eluting cartilage scaffold provided in Example 2 and the control scaffold (linear structure scaffold) prepared in Example 3 were examined using an Instron electronic universal material analyzer at a rate of 1 mm / min and a compression rate of 15%. The stress-strain curves are shown below. Figure 4 ,Depend on Figure 4 It can be seen that the stent prepared with the V-shaped structural unit of this invention is more easily compressed than the linear stent, which is beneficial for implantation into the defect site after compression during use. In this embodiment, the recovery rate of the stent was observed after compression by 15%, and the results are shown in […]. Figure 5 It can be seen that the stent prepared by this invention can almost completely recover to its original height before compression, achieving a recovery rate of over 99%, while the recovery rate of the control group linear stent is less than 70%. This shows that linear lines are difficult to deform, and some linear lines will be broken after being compressed by a large force and cannot recover their original shape. Therefore, this invention can achieve good compressibility and shape recovery, which is beneficial to practical applications.
[0046] In addition, the scaffold undergoes a direct deformation and compression treatment. The specific method is as follows: a 500 g weight is placed on the scaffold and held for 1 minute to compress the scaffold to a certain extent. Then the weight is removed, and the slow-release cartilage scaffold naturally rebounds and restores its shape.
[0047] The porous sustained-release drug cartilage scaffold designed in this invention features a structure that allows for compressibility and elasticity, as well as surface structure fitting, enabling self-fixation after implantation and preventing loosening and displacement of the implant.
[0048] This invention provides a concept and method for a sustained-release drug-eluting cartilage scaffold. Many methods and approaches exist for implementing this technical solution; the above description is merely a preferred embodiment. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention. All components not explicitly stated in this embodiment can be implemented using existing technology.
Claims
1. A sustained-release drug-eluting cartilage scaffold, characterized in that, This includes several support units (101) stacked sequentially; The support unit (101) includes two polygonal structures (102), which are three-dimensionally connected by several parallel V-shaped connecting parts (103). The polygonal structure (102) is formed by connecting two sets of parallel V-shaped connecting parts (103) end to end; The V-shaped connecting part (103) is formed by two connecting segments (4) connected by a line connection (2).
2. The sustained-release drug-eluting cartilage scaffold according to claim 1, characterized in that, The support unit (101) is formed by three-dimensionally connecting two polygonal structures (102) through their network connection points (3) with four parallel V-shaped connection parts (103); The network connection (3) is the beginning and end of the V-shaped connection (103).
3. The sustained-release drug-eluting cartilage scaffold according to claim 1, characterized in that, The length of the connecting segment (4) is 0.1~5 mm and the diameter is 0.1~2 mm.
4. The sustained-release drug-eluting cartilage scaffold according to claim 3, characterized in that, The length of the connecting segment (4) is 0.1~0.3 mm and the diameter is 0.2~0.3 mm.
5. The sustained-release drug-eluting cartilage scaffold according to claim 1, characterized in that, In the V-shaped connecting part (103), the included angle between the two connecting segments (4) is an obtuse angle.
6. The sustained-release drug-eluting cartilage scaffold according to claim 5, characterized in that, The included angle between the two connecting segments (4) is 110 to 150 degrees.
7. The sustained-release drug-eluting cartilage scaffold according to claim 1, characterized in that, The porosity of the sustained-release drug cartilage scaffold is 50%~85%.
8. The sustained-release drug-eluting cartilage scaffold according to claim 7, characterized in that, The porosity of the sustained-release drug cartilage scaffold is 60%~70%.
9. The sustained-release drug-eluting cartilage scaffold according to claim 1, characterized in that, The material of the sustained-release drug cartilage scaffold includes polyurethane.