CN210644262U

CN210644262U - Novel degradable support

Info

Publication number: CN210644262U
Application number: CN201822051642.0U
Authority: CN
Inventors: 王君毅; 王国辉; 赵迎红; 蔡涛; 张晨朝
Original assignee: Fuwai Hospital of CAMS and PUMC
Current assignee: Shanghai baixin'an Biotechnology Co.,Ltd.
Priority date: 2018-12-07
Filing date: 2018-12-07
Publication date: 2020-06-02
Anticipated expiration: 2028-12-07

Abstract

The utility model discloses a novel degradable support relates to and implants the medical instrument field, including interior muscle, polymer substrate layer and medicine layer, wherein, interior muscle is the metal substrate that has the development function under the X-ray machine, the polymer substrate layer is formed by polymer solution mixture, wraps up layer upon layer metal substrate strengthens it, the medicine layer cover in polymer substrate layer surface. To current metal alloy degradation speed slow excessively, degradation product complicated easily with the blood vessel produce the problem of rejection reaction, the not enough easy cracked problem of polymer degradable support toughness, develop incomplete problem after the support surface is filled with the development thing, the utility model discloses combine together two kinds of substrates, provide one kind have good moulding, good radial support intensity, can develop completely the support.

Description

Novel degradable support

Technical Field

The utility model relates to an implant medical instrument field, especially relate to a novel degradable support.

Background

Stents have gained wider and wider application in the field of cardiovascular disease as an important instrument for treating vascular stenosis. For the metal stent which is widely applied to clinic at present, as the metal stent is permanently remained in a human body after completing a treatment task, the metal stent has the defects of weakening MRI or CT images of coronary arteries, interfering surgical blood circulation reconstruction, blocking the formation of collateral circulation, inhibiting positive remodeling of blood vessels and the like. Based on these problems, biodegradable stents have attracted much attention as a possible alternative solution. The biodegradable stent is made of a degradable polymer material or a metal material. After the scaffold is implanted into a lesion part, the biodegradable scaffold can play a role in supporting blood vessels in a short time, so that the revascularization is realized. After the treatment is finished, the biodegradable stent can be degraded into organic matters which can be absorbed and metabolized by the human body in the human body environment, and finally the stent can disappear. In addition, the shelf life of the stent is short, which can affect the use of the stent, as the stent must be stored for a certain period of time after being prepared.

The degradable stent is made of absorbable metal and polymer, the density of the polymer material is low, the X-ray impermeability of the material is poor, the vascular stent prepared from the polymer is almost invisible under the assistance of medical imaging equipment and a digital subtraction technique, so that a doctor cannot accurately position the stent in the operation process, and therefore a developing mechanism needs to be additionally arranged on the polymer stent, so that the developing mechanism can be identified by the doctor under DSA. Namely, the lack of visibility of the stent base is compensated by the developing structure having good visibility.

In order to solve the problem of scaffold degradation, chinese patent 2014108566258 proposes a degradable iron-based alloy scaffold, but the iron-based scaffold itself has too low degradation speed, and needs to be doped with at least one of C, N, O, S, P, Mn, Pd, Si, W, Ti, Co, Cr, Cu, Re, and can be doped into pure iron to form the medical iron-based alloy. And various polymers are added to accelerate complete degradation, and degradation products are complex and easy to generate rejection reaction with blood vessels.

In order to improve the radial supporting strength of the stent, chinese patent 2017112132378 proposes a polylactic acid and its copolymer stent, which improves the radial supporting strength due to the high orientation in the radial direction, but greatly loses the toughness of the stent, so that the stent is easily broken after passing through the tortuous blood vessels.

To improve the development performance of the stent, chinese patent 2015103951018 proposes a blood vessel stent, which is filled with a developer on the surface or structure of the stent, but cannot achieve complete development of the entire stent

Accordingly, those skilled in the art have endeavored to develop a stent having good shaping, good radial support strength, and being capable of being fully developed.

SUMMERY OF THE UTILITY MODEL

In view of the above-mentioned defects of the prior art, the technical problem to be solved by the present invention is to develop a stent which has good shaping, good radial support strength and can be developed completely, and compared with the traditional degradable stent, the present invention uses a single base material, and combines two base materials, and ensures that the stent does not have restenosis by using the good radial support of the polymer; the good shaping of the metal base material is utilized, the stent is guaranteed not to be broken after reaching the pathological change through the tortuous blood vessels and being stretched, and the purpose of complete development of the whole stent is achieved.

In order to achieve the above object, the present invention provides a novel degradable stent, which comprises an inner rib, a polymer substrate layer and a drug layer, wherein the inner rib is a metal substrate with a developing function under an X-ray machine, the polymer substrate layer is formed by mixing a polymer solution, and is wrapped at the periphery of the metal substrate to form a solid polymer substrate layer with a supporting effect, the polymer solution is one or more of poly (lactic-co-glycolic acid) (PLGA), poly (lactic-co-glycolic acid) (PGLA), poly (lactic-co-glycolic acid) (PLA), poly (DL-lactide-co-glycolide) (PDLGA), the drug layer is formed by mixing a drug and a polymer solution, the drug is one or more of paclitaxel, sirolimus and everolimus and covers the surface of the polymer base material layer.

Further, the metal substrate is one of an iron-based alloy, a magnesium-based alloy, a zinc-based alloy and an aluminum-based alloy.

Further, the metal base material is single or multiple, and the cross section of the metal base material is rectangular or circular.

Further, the metal base materials are single-cavity metal tubes which are independently arranged in parallel.

Furthermore, the metal base materials are multiple and are arranged in a hollow twist-shaped combination mode.

Further, the cross-sectional area of the polymer base material layer is more than 10 times the cross-sectional area of the metal base material.

The beneficial effects of the utility model reside in that: the utility model discloses combine the good plasticity of metal degradable support and the advantage of the good support nature of polymer degradable support, for metal material, the polymer substrate layer of degradable support presents solid-state after solidifying, can bear certain pressure for by the parcel have good radial support nature and intensity at the intraformational metal substrate of polymer substrate, ensure can not take place the intravascular restenosis. Compared with polymer materials, the degradable stent has the advantages that the plasticity is improved, the stent is not easy to break, and the complete development can be realized.

The conception, the specific structure and the technical effects of the present invention will be further described with reference to the accompanying drawings, so as to fully understand the objects, the features and the effects of the present invention.

Drawings

FIG. 1 is a schematic view of a single metal substrate according to a preferred embodiment of the present invention;

fig. 2 is a top view of a plurality of metal inner ribs according to a preferred embodiment of the present invention;

fig. 3 is a side view of a multi-metal inner rib structure according to a preferred embodiment of the present invention;

fig. 4 is an oblique view of a structure of a plurality of metal inner ribs according to a preferred embodiment of the present invention;

fig. 5 is a cross section of two metal substrates independently arranged in a straight frame according to a preferred embodiment of the present invention.

Detailed Description

The technical contents of the preferred embodiments of the present invention will be more clearly understood and appreciated by referring to the drawings attached to the specification. The present invention may be embodied in many different forms of embodiments, and the scope of the invention is not limited to the embodiments described herein.

In the drawings, structurally identical elements are represented by like reference numerals, and structurally or functionally similar elements are represented by like reference numerals throughout the several views. The size and thickness of each component shown in the drawings are arbitrarily illustrated, and the present invention is not limited to the size and thickness of each component. The thickness of the components may be exaggerated where appropriate in the figures to improve clarity.

Example one

As shown in fig. 1, the utility model provides a single metal substrate structure's specific embodiment, the metal substrate 1 of selecting can be iron-based alloy, magnesium-based alloy, zinc-based alloy, aluminium-based alloy etc. have the material of development function under the X-ray machine, also can obtain through laser cutting by single chamber tubular metal resonator, and metal substrate 1 can be single, also can many independent row.

Fig. 2 is a top view of a hollow twist-shaped combination arrangement structure of a plurality of metal inner ribs according to a preferred embodiment of the present invention, wherein the metal wires 21 and the metal wires 22 are 2 of four metal wires with the same cross section. The preformed polymer filaments 23 are wrapped by four wires (including wires 21, 22) to form a bundle. Fig. 3 is a side view of the combination arrangement of the hollow twist-shaped inner ribs, fig. 4 is an oblique view of the combination arrangement of the hollow twist-shaped inner ribs, the inner ribs are arranged in a hollow twist-shaped combination manner, the combination arrangement of the twist-shaped combination manner can greatly improve the toughness of the support to avoid the support from breaking, but the flexibility of the support is lost. In this embodiment, a hollow twist-shaped arrangement method is designed, so that each metal substrate has an independent moving space to make up for the loss in flexibility, and the specific implementation process is as follows: the metal substrate 21 and the metal substrate 22 are crossed in a cross shape, the interior of the joint is designed into a hollow structure 23, a polymer lining core which can be dissolved in a dip-coating solution is filled in the hollow structure 23, after weaving is completed, the whole metal substrate is wholly immersed in the dip-coating solution, and the polymer lining core can be dissolved to obtain a hollow twist-shaped structure.

Example two

Fig. 5 shows a cross section of two metal substrates independently arranged in a straight frame according to another preferred embodiment of the present invention, and the manufacturing process of the present invention can be specifically explained by this embodiment. The inner ribs are two metal base materials with the same material type and are arranged independently, and the metal base materials 1 are iron-based alloy, magnesium-based alloy, zinc-based alloy and aluminum-based alloy which have a developing function under an X-ray machine; the polymer base material layer 2 formed by wrapping polymer solution around the two metal base materials, wherein the polymer solution is one or more of PLLA, PDLLA, PDLA, PLGA, PGLA, PLA and PDLGA, the polymer base material layer 2 is formed by wrapping the polymer solution around the polymer base material layer 2, and the polymer base material layer 2 is solid after being solidified and can bear certain pressure, so that the metal base material 1 wrapped in the polymer base material layer 2 has good radial support performance, and restenosis is ensured not to occur; the periphery of the polymer substrate layer 2 is covered with a medicine layer 3 mixed by medicine and polymer solution.

The polymer base material layer 2 can be obtained by spraying on the surface of the metal base material layer 1, and the specific implementation process is as follows: dissolving the polymer solution in one or more organic solvents of methanol, ethanol, isopropanol, acetone, tetrahydrofuran, acetonitrile and chloroform to form a spraying solution, fully oscillating and uniformly mixing, covering a layer of spraying solution with the thickness of 10-15um on the surface of the metal substrate 1 at the spraying speed of 0.01-0.06mm/min, and then airing for 10min at the temperature of 20-25 ℃ and at the RH of 40-60%; spraying on the surface again, repeating the above steps until polymerizationThe cross-sectional area of the metal substrate 1 covered by the solution is 0.01mm²To 0.04mm²To (c) to (d); and (3) conveying the metal substrate 1 sprayed with the spraying solution into a drying oven, and drying at the temperature of 10-20 ℃ lower than the glass transition temperature of the polymer solution material to form the polymer substrate layer 2.

The drug layer 3 can be obtained by spraying a drug solution on the surface of the polymer substrate layer 2, and the specific implementation process is as follows: dissolving the drug and the polymer solution in one or more organic solvents of methanol, ethanol, isopropanol, acetone, tetrahydrofuran, acetonitrile and chloroform to form a drug solution, fully oscillating and uniformly mixing, covering a layer of drug solution with the thickness of 5-10um on the surface of the polymer base material layer at the spraying rate of 0.01-0.03mm/min, sending the sprayed polymer base material into an oven, and drying at the temperature of 10-20 ℃ lower than the glass transition temperature of the drug solution material to form the drug layer 3.

EXAMPLE III

In this embodiment, the polymer substrate layer 2 may also be obtained by dip-coating the metal substrate 1, and the specific implementation process is as follows: dissolving the polymer solution in one or more organic solvents of methanol, ethanol, isopropanol, acetone, tetrahydrofuran, acetonitrile and chloroform to form a dip-coating solution, and fully oscillating and uniformly mixing; immersing the metal substrate 1 in the dip-coating solution, taking out and airing after 1min, turning the metal substrate 1180 ℃ after airing, immersing the metal substrate in the dip-coating solution again, taking out and airing after 1min, and ensuring that the dip-coating solutions at two ends of the metal substrate 1 are coated uniformly; the coating thickness is 15-25um, and the positive and negative times are recorded as a cycle; then airing for 10min at 20-25 ℃ and 40-60% RH; repeating the above steps until the cross-sectional area of the metal substrate 1 covered by the dip coating solution is 0.01mm²To 0.04mm²To (c) to (d); and (2) sending the metal substrate 1 dipped with the dip-coating solution into an oven, and drying at the temperature of 10-20 ℃ lower than the glass transition temperature of the polymer solution material to form the polymer substrate layer 2. Furthermore, the polymer substrate layer 2 may also be obtained by 3D printing of the metal substrate 1. Finally obtaining a polymer substrate layer 2, the polymerizationThe material substrate layer 2 is solid after solidification and can bear certain pressure, so that the metal substrate 1 wrapped in the polymer substrate layer 2 has good radial support.

The drug layer 3 can also be obtained by dip-coating the polymer substrate layer 2, and the specific implementation process is as follows: dissolving the drug and the polymer solution in one or more organic solvents of methanol, ethanol, isopropanol, acetone, tetrahydrofuran, acetonitrile and chloroform to form a drug solution, and fully oscillating and uniformly mixing; immersing the polymer substrate layer in the medicine solution, taking out after 1min, and airing; after airing, turning the polymer base material layer for 180 degrees, immersing the polymer base material layer in the drug solution again, taking out the polymer base material layer after 1min, airing to ensure that the drug solutions at two ends of the polymer base material layer are uniformly coated, adjusting the thickness of dip coating by controlling the concentration of the drug solution, wherein the coating is thicker when the concentration is higher, and is thinner when the concentration is lower; and (3) feeding the metal substrate 1 coated with the drug solution into an oven, and drying at the temperature of 10-20 ℃ lower than the glass transition temperature of the drug solution material to form the drug layer 3. In addition, the drug layer 3 may also be obtained by 3D printing the polymer base layer 2.

The foregoing has described in detail preferred embodiments of the present invention. It should be understood that numerous modifications and variations could be devised by those skilled in the art in light of the teachings of this invention without undue experimentation. Therefore, the technical solutions that can be obtained by a person skilled in the art through logic analysis, reasoning or limited experiments based on the prior art according to the concepts of the present invention should be within the scope of protection defined by the claims.

Claims

1. The utility model provides a novel degradable support, its characterized in that, includes interior muscle, polymer substrate layer and medicine layer, wherein, interior muscle is the metal substrate that has the development function under the X-ray machine, the polymer substrate layer is formed by polymer solution mixture, and the parcel is in metal substrate is peripheral, forms solid-state, has the supporting effect the polymer substrate layer, the medicine layer cover in polymer substrate layer surface.

2. The novel degradable stent of claim 1 wherein said metal substrate is one of an iron-based alloy, a magnesium-based alloy, a zinc-based alloy and an aluminum-based alloy.

3. The novel degradable stent of claim 1, wherein said metal substrate is single or multiple, and said metal substrate has a rectangular or circular cross-section.

4. The novel degradable stent of claim 1 wherein said metal substrate is a single lumen metal tube.

5. The novel degradable stent of claim 1 wherein the cross-sectional area of the polymeric substrate layer is more than 10 times the cross-sectional area of the metal substrate.