WO2012003803A1

WO2012003803A1 - A drug carrying metal stent and manufacturing method therefor

Info

Publication number: WO2012003803A1
Application number: PCT/CN2011/076976
Authority: WO
Inventors: 李俊菲; 胡燕; 姚瑶; 唐智荣; 罗七一
Original assignee: 微创医疗器械(上海)有限公司
Priority date: 2010-07-09
Filing date: 2011-07-08
Publication date: 2012-01-12

Abstract

A metal stent and a manufacturing method therefor. The metal stent comprises a stent body (1), the stent body (1) a having on the exterior surface thereof a plurality of holes distributed, and the interior surface of the stent body (1) being a smooth surface. The metal stent is for use as a drug-eluting stent (DES), the holes of the metal stent are used to carry a drug, instead of a polymer coating layer being used to carry the drug, thus an implantation thereof into a human body can avoid a problem related to the use of the polymer. Concurrently, with the metal stent having holes provided only on the exterior surface, the direction of drug release is therefore controllable, and the utilization rate of the drug is increased.

Description

Medicine-loaded metal stent and preparation method thereof

The present application relates to the field of medical device technology, and in particular to a metal stent for a drug eluting stent and a method of preparing the same. Background technique

In recent years, clinically drug-eluting stents (DES) have been widely used. Drug-eluting stents, also known as drug-eluting stents, carry the drug through a polymer coated on the surface of the metal stent or through a hole in the surface of the metal stent. Compared with the bare metal stent, after being implanted into the human body, the drug-eluting stent can continuously release the drug to the diseased tissue in contact with it, thereby effectively inhibiting the proliferation of the smooth muscle of the blood vessel wall and reducing the occurrence of restenosis in the blood vessel stent. However, through the prior art research, the applicant found that the existing metal stent used in the drug eluting stent has the following problems: 1. Using the polymer to carry the drug, after long-term implantation into the human body, due to the long-term polymer of the surface The presence or degradation of the polymer can lead to a sustained inflammatory response, which in turn may lead to delayed endothelialization and late vascular restenosis. 2. The drug is carried on the surface of the metal stent. Since the surface of the metal stent is provided with micropores, the inner and outer surfaces of the drug-eluting stent and even the side surface are coated with drugs, so after being implanted into the human body, The concentration of the intravascular drug is large, and the release direction is not effectively controlled, so that a part of the drug cannot be absorbed by the blood vessel wall, and the effective utilization rate of the drug is low. Summary of the invention

In view of this, one of the purposes of the present application is to provide a metal stent and a preparation method thereof, which can not only avoid the problem caused by the polymer, but also increase the controlled release of the drug after the metal stent is used as the drug eluting stent. Capacity and effective utilization. To achieve the above object, the present invention provides the following technical solutions: A metal bracket includes a bracket body, the outer peripheral surface of the bracket body is evenly distributed with a plurality of holes, and an inner surface of the bracket body is a smooth surface. Preferably, the bracket body has a tubular mesh shape. Preferably, the pore has a pore diameter and a pore depth of 0.5 μm to 10 μm. Preferably, the metal stent is a human intraluminal stent. Preferably, the material of the stent body is stainless steel, cobalt-based alloy, nickel-based alloy, titanium alloy or degradable magnesium alloy with good biocompatibility and mechanical properties. Preferably, the human intraluminal stent comprises: a coronary artery stent, an intracranial vascular stent, a peripheral vascular stent, a splenic artery stent, an intraoperative stent, a heart valve stent, a biliary stent, an esophageal stent, an intestinal stent, and a pancreas Tube stent, urethral stent or tracheal stent. A method for preparing a metal stent, comprising:

Pre-treating the surface of the stent body to remove impurities on the surface of the stent body; adding an electrolyte to the electrolytic cell, the electrolyte comprising 0.02%-10% nitric acid; using the pre-treated stent body as an anode An electrochemical corrosion reaction is performed in the electrolyte to obtain a metal stent having a plurality of pores uniformly distributed on the outer peripheral surface. Preferably, the pretreatment comprises: polishing, washing and/or drying. Preferably, the electrolyte further comprises: 0.01% to 100% ethylene glycol solution and/or 0.01% to 100% glycerol solution. Preferably, the electrochemical corrosion reaction has a reaction voltage of 2 to 40 V and a reaction time of 5 to 300 s. The method for preparing the metal stent provided by the embodiment of the present application can be electrochemically etched in an electrolyte containing 0.02% to 10% nitric acid by using the stent body as an anode. The outer peripheral surface of the stent body is etched into holes having different pore sizes and pore depths, and the inner surface of the stent body is a smooth surface without micropores. And by adjusting the concentration, reaction voltage and reaction time of each formulation in the electrolyte, the pore size and pore depth of the pores can be freely controlled. The metal stent prepared by the method has pores distributed only on the outer peripheral surface thereof, and no corrosion on the inner surface of the metal stent. Therefore, when the metal stent is used for a drug-eluting stent, the hole of the metal stent is loaded with the drug, and the polymer coating is not used for drug loading, thereby avoiding the problem caused by the use of the polymer, and the metal stent has only the outer peripheral surface. There are holes, so you can control the release direction of the drug and improve the utilization of the drug. The second object of the present application is to provide a human body lumen drug-loading stent and a preparation method thereof, wherein the human body cavity drug-loading stent adopts a single-sided micro-pore drug-loading method, which can avoid the problem caused by the polymer drug-loading, and can also Achieve targeted release drugs, increase drug release and effective utilization. In order to achieve the above objectives, the technical solution is as follows:

A body lumen drug-loading stent comprises a stent body, the outer peripheral surface of the stent body is evenly distributed with a plurality of holes, and the plurality of holes are filled with a drug, and the inner surface of the stent body is a smooth surface. Preferably, the bracket body has a tubular mesh shape. Preferably, the pore has a pore diameter and a pore depth of 0.1 μη to 10 μm. Preferably, the stent body comprises: a coronary artery stent, an intracranial vascular stent, a peripheral vascular stent, a splenic artery stent, an intraoperative stent, a heart valve stent, a biliary stent, an esophageal stent, an intestinal stent, a pancreatic duct stent, Urethral stent or tracheal stent. Preferably, the material of the stent body is stainless steel, cobalt-based alloy, nickel-based alloy, titanium alloy or degradable magnesium alloy with good biocompatibility and mechanical properties. Preferably, the medicament comprises: one or more of an anti-inflammatory drug, an anti-platelet drug, an anticoagulant, an anticancer drug, an immunosuppressive agent, and a hormone. A preparation method of a human body cavity drug-loading stent, comprising:

Pre-treating the surface of the stent body to remove impurities on the surface of the stent body; adding an electrolyte to the electrolytic cell, the electrolyte comprising 0.02%-10% nitric acid; using the pre-treated stent body as an anode Performing an electrochemical corrosion reaction in the electrolyte to obtain a stent body having a plurality of holes on the outer peripheral surface;

Dissolving the drug in an organic solvent to obtain a drug solution;

The stent body having a plurality of holes on the outer peripheral surface is immersed in the drug solution, and after ultrasonic treatment for a certain period of time, it is taken out and dried to obtain a human body cavity drug-loading stent.

Preferably, the pretreatment comprises polishing, washing and/or drying. Preferably, the electrolyte further comprises: 0.01% to 100% ethylene glycol solution and/or 0.01% to 100% glycerol solution. Preferably, the electrochemical corrosion reaction has a reaction voltage of 2 to 40 V and a reaction time of 5 to 300 s. Compared with the prior art, the human body lumen drug-loading support provided by the embodiment of the present application adopts a single-sided micro-pore drug-loading method, and the stent body has only micropores uniformly distributed on the outer peripheral surface, and the micro-pore is filled with the drug. The inner surface is a smooth surface with no micropores. Moreover, by adjusting the concentration, reaction voltage and reaction time of each formula in the electrolyte, the pore diameter and the pore depth of the pores on the stent body can be freely controlled, and the drug loading amount of the drug-loading stent of the human lumen can be controlled. Therefore, after the human body cavity drug-loading stent is implanted into the human body, not only the use of the polymer can be avoided. The problem caused by the drug loading, and the human body cavity drug-loading stent only releases the drug to the blood vessel wall contacting the micropore on the peripheral surface, thereby realizing the targeted release of the drug and increasing the controlled release ability and effective utilization rate of the drug. . DRAWINGS

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below. Obviously, the drawings in the following description are only It is a few embodiments described in the present application, and other drawings can be obtained from those skilled in the art without any creative work.

1 is a schematic structural view of a metal bracket provided by an embodiment of the present application;

2 is a schematic structural view of a metal stent according to an embodiment of the present invention; FIG. 3 is a process flow diagram of a method for preparing a metal stent according to an embodiment of the present invention; Figure 5 is a schematic view showing a partial structure of a human body lumen drug-loading support provided by an embodiment of the present application;

6 is a process flow diagram of a method for preparing a human body lumen drug-loaded stent according to an embodiment of the present application. detailed description

The technical solutions in the embodiments of the present application are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present application. The embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present application without departing from the inventive scope should fall within the scope of the present application. FIG. 1 is a schematic structural view of a metal bracket provided by an embodiment of the present application. 2 is a schematic partial structural view of a metal bracket provided by an embodiment of the present application. As shown in FIGS. 1 and 2, the main body portion of the metal bracket is a bracket body 1, and a plurality of holes are evenly distributed on the outer peripheral surface of the bracket body 1. The above-mentioned holes are only located on the outer peripheral surface of the bracket body 1, and on the inner surface of the bracket body 1, there is a smooth surface, and no holes are present. In the embodiment of the present application, the shape of the hole is arbitrary, and the size of the hole diameter may be selected from Ο.ΐ μηι 1010ηηι, and the aperture in the embodiment of the present application refers to the effective diameter of the hole, that is, according to a certain collection rule, After the hole of the shape is converted into a circular hole of equivalent diameter, the diameter of the hole of the hole; the hole depth of the hole can also be selected in Ο. ΐ μηι ~10μηι, where the depth of the hole means that the bottom of the hole is outside the body of the bracket 1 The distance of the surface, the choice of the hole depth can not only load the drug in the hole in the stent body 1 when the metal stent is used for the drug eluting stent, but also does not affect the physical and mechanical properties of the stent body 1 including the supporting strength. . In the embodiment of the present application, the structure of the stent body 1 is a tubular mesh, and is a human body intraluminal stent well known to those skilled in the art, including but not limited to coronary stents, intracranial stents, and peripheral stents. , splenic artery stent, intraoperative stent, heart valve stent, biliary stent, esophageal stent, intestinal stent, pancreatic duct stent, urethral stent or tracheal stent. In addition, the material of the stent body 1 is selected to be a material having good biocompatibility and mechanical properties, such as stainless steel, cobalt-based alloy, nickel-based alloy, titanium alloy or degradable magnesium alloy. The embodiment of the present application further provides a method for preparing the above metal stent, and FIG. 3 is a process flow diagram of the method. As shown in FIG. 3, the preparation method includes:

The surface of the stent body is pretreated to remove impurities on the surface of the stent body. Pre-treatment of the stent body surface includes, but is not limited to, polishing, cleaning, and/or drying, and may be otherwise well known to those skilled in the art. The pretreatment removes the oxide layer, grease or other impurities on the surface of the stent body to avoid affecting the electrochemical corrosion effect of the stent body, thereby causing uneven distribution of the pores on the surface of the stent body 1 or controlling the pore diameter and pore depth of the pore body. An electrolyte is added to the electrolytic cell, and the electrolyte is formulated to be 0.02% to 10% nitric acid. In the embodiment of the present application, the formulation of the electrolyte is 0.02%-10% nitric acid, and preferably the electrolyte may further comprise 0.01% ~ 100% ethylene glycol solution and / or 0.01% ~ 100% glycerol solution. The precursor body after the pretreatment is used as an anode, and an electrochemical corrosion reaction is performed in the electrolyte to obtain a stent body having a plurality of holes uniformly distributed on the outer peripheral surface. In the embodiment of the present application, the reaction voltage of the electrochemical corrosion reaction is 2V~40V, and the reaction time is 5s~300s. Since the structure of the stent body is tubular, the current density of the inner and outer surfaces of the stent body may be different during electrochemical etching, wherein the current density of the outer surface of the stent body is greater than the current density of the inner surface, and thus may be formed on the outer surface of the stent. Multiple, uniform holes without micropores on the inner surface. In addition, by controlling the concentration, reaction voltage and reaction time of each formulation in the electrolyte, the pore diameter and pore depth of the outer peripheral surface of the stent can be freely controlled, and the pore diameter ranges from 0.1 μm to 10 μm, and the pore depth ranges from Ο. ΐ μηι ~10μηι. For example: When the concentration of nitric acid in the electrolyte is 0.02%~0.2%, the pore size and pore depth of the surface of the stent body obtained by the reaction are all 0.1 μηι ~2μηι _; when the concentration of nitric acid in the electrolyte is 0.2%~2% The pore size of the surface of the stent body obtained by the reaction ranges from 2μηι to 5μηι, and the pore depth ranges from Ιμηι to 5μηΐ; when the concentration of nitric acid in the electrolyte is 2% to 10%, the pore diameter of the surface of the stent body obtained by the reaction The range is 5μηι ~ 10μηι, and the pore depth ranges from 2μηι to 10μηι. Compared with the prior art, the method for preparing the metal stent provided by the embodiment of the present invention uses the stent body as an anode to perform electrochemical corrosion in an electrolyte containing 0.02% to 10%, and can be only on the outer peripheral surface of the stent body. The holes are etched into pores of different pore sizes and pore depths, and the pore size and pore depth of the pores can be controlled by adjusting the concentration of nitric acid in the electrolyte. The metal stent prepared by the metal stent preparation method has pores distributed only on the outer peripheral surface thereof. There is no corrosion on the inner surface and side of the metal bracket. Therefore, when the metal stent is used for a drug-eluting stent, the hole of the metal stent is loaded with the drug, and the polymer coating is not used for drug loading, thereby avoiding the problem caused by the use of the polymer, and the metal stent has only the outer peripheral surface. There are holes, so after loading the drug, you can control the release direction of the drug and improve the drug utilization rate. 4 is a schematic structural view of a human body lumen drug-loading support provided by an embodiment of the present application. FIG. 5 is a partial structural diagram of a human body lumen drug-loading support provided by an embodiment of the present application. As shown in FIG. 4 and FIG. 5, the main body portion of the human body cavity drug-loading stent is a stent body 1. A plurality of holes are evenly distributed on the outer circumferential surface of the stent body 1, and a plurality of holes are filled with drugs. The above holes are only located on the outer peripheral surface of the bracket body 1, and the bracket body

The inner surface of 1 is a smooth surface with no holes. In the embodiment of the present application, the shape of the hole is arbitrary, and the size of the hole diameter can be selected in Ο.ΐ μηι ~10μηι, where the aperture refers to the effective diameter of the hole, that is, the holes of various shapes are converted according to a certain collection law. After the circular hole of the equivalent diameter, the diameter of the hole of the hole; the hole depth of the hole can also be selected in Ο.ΐ μηι ~ 10μηι, where the hole depth refers to the distance from the bottom of the hole to the outer surface of the body 1 of the stent. In practical applications, the choice of the pore size and pore depth of the pore can be reasonably selected according to the drug loading of the vascular drug stent. In the embodiment of the present application, the structure of the stent body 1 is a tubular mesh, and is a human body intraluminal stent well known to those skilled in the art, including but not limited to coronary stents, intracranial stents, and peripheral stents. , splenic artery stent, intraoperative stent, heart valve stent, biliary stent, esophageal stent, intestinal stent, pancreatic duct stent, urethral stent or tracheal stent. In addition, the material of the stent body 1 is selected to be a material having good biocompatibility and mechanical properties, such as stainless steel, cobalt-based alloy, nickel-based alloy, titanium alloy or degradable magnesium alloy. In the embodiment of the present application, the medicine in the hole in the stent body 1 is a medicine well known to those skilled in the art, including but not limited to: anti-inflammatory drugs, anti-platelet drugs, anticoagulants, anticancer drugs, Immunosuppressants and/or hormones, preferably rapamycin and its derivatives, paclitaxel and its derivatives, probucol and its derivatives, dexamethasone and its derivatives, asiaticoside, heparin, aspirin, One or more of cilostazol, ticlopidine, triptolide, cyclosporine, tacrolimus or estradiol, more preferably rapamycin. The embodiment of the present application further provides a preparation method of the above-mentioned human body cavity drug-loading stent, and FIG. 6 shows a process flow chart of the method. As shown in FIG. 6, the preparation method includes:

The surface of the stent body is pretreated to remove impurities on the surface of the stent body. Pre-treatment of the stent body surface includes, but is not limited to, polishing, cleaning, and/or drying, and may be otherwise well known to those skilled in the art. The pretreatment removes the oxide layer, grease or other impurities on the surface of the stent body to avoid affecting the electrochemical corrosion effect of the stent body, thereby causing uneven distribution of the pores on the surface of the stent body 1 or controlling the pore diameter and pore depth of the pore body. An electrolyte is added to the electrolytic cell, and the electrolyte is formulated to be 0.02% to 10% nitric acid. In the embodiment of the present application, the formulation of the electrolyte is 0.02%-10% nitric acid, and preferably the electrolyte may further comprise 0.01% ~ 100% ethylene glycol solution and / or 0.01% ~ 100% glycerol solution. The precursor body after the pretreatment is used as an anode, and an electrochemical corrosion reaction is performed in the electrolyte to obtain a stent body having a plurality of holes uniformly distributed on the outer peripheral surface. In the embodiment of the present application, the reaction voltage of the electrochemical corrosion reaction is 2V~40V, and the reaction time is 5s~300s. Since the structure of the stent body is tubular, when electrochemical corrosion is performed, The current density of the inner and outer surfaces of the frame body may be different, wherein the current density of the outer surface of the stent body is greater than the current density of the inner surface, so that a plurality of uniform holes may be formed on the outer surface of the stent, and the inner surface has no holes. Dissolving the drug in a volatile organic solvent to obtain a drug solution;

In the examples of the present application, the volatile organic solvent includes, but is not limited to, methanol, ethanol, acetone, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, pentamidine, n-glycol and/or dimethyl The sulfoxide is preferably acetone. The use of an organic solvent to dissolve the drug is to allow the drug to be more evenly distributed in a plurality of pores on the outer surface of the stent body, and the organic solvent is volatile, so that no residue remains after the drug loading is completed. The stent body having a plurality of holes on the outer peripheral surface is immersed in the drug solution, and after ultrasonic treatment for a certain period of time, it is taken out and dried to obtain a human body cavity drug-loading stent. Ultrasonic treatment is to make the drug solution adhere more uniformly to the hole in the stent body, so that the drug distribution on the obtained human body cavity drug-loading stent is uniform. In addition, according to the drug loading of the vascular drug stent, the pore size and pore depth of the outer peripheral surface of the stent can be freely controlled by controlling the concentration, reaction voltage and reaction time of each formulation in the electrolyte, so that the vascular drug can be controlled. The drug loading of the stent. The pore diameter of the stent body ranges from Ο. ΐ μηι ~10μηι, and the pore depth ranges from Ο.ΐ μηι to 10μηι. For example: When the concentration of nitric acid in the electrolyte is 0.02%~0.2%, the pore size and pore depth of the surface of the stent body obtained by the reaction are all 0.1 μηι ~2μηι _; when the concentration of nitric acid in the electrolyte is 0.2%~2% The pore size of the surface of the stent body obtained by the reaction ranges from 2μηι to 5μηι, and the pore depth ranges from Ιμηι to 5μηι _; when the concentration of nitric acid in the electrolyte is 2% to 10%, the pore diameter of the surface of the stent body obtained by the reaction is obtained. The range is 5μηι ~ 10μηι, and the pore depth ranges from 2μηι to 10μηι. The human body cavity drug-loading stent provided by the embodiment of the present application adopts a single-sided micro-pore drug-loading method, and the stent body has only micropores uniformly distributed on the outer peripheral surface, and the micro-pore is filled with the drug. The inner surface is a smooth surface with no micropores. Moreover, by adjusting the concentration, reaction voltage and reaction time of each formula in the electrolyte, the pore diameter and the pore depth of the pores on the stent body can be freely controlled, and the drug loading amount of the drug-loading stent of the human lumen can be controlled. Therefore, after the human body lumen drug-loading stent is implanted into the human body, not only the problem caused by the polymer drug loading can be avoided, but also the human body cavity drug-loading stent releases the drug only to the blood vessel wall contacting the micro-hole of the peripheral surface. Thereby, targeted release of the drug can be achieved, and the controlled release ability and effective utilization rate of the drug can be increased. In order to further understand the present invention, a method for preparing a metal stent for a drug eluting stent and a method for preparing a human body lumen drug delivery stent provided by the present invention will be described in detail below with reference to the examples. Example 1:

The holder body is polished, then washed, and finally dried. Example 2:

Follow the steps below to prepare the electrolyte:

0.1 ml of nitric acid, 100 ml of ethylene glycol solution and 300 ml of glycerol solution were added to 100 ml of purified water, and the mixture was mixed and used. Example 3:

Follow the steps below to prepare the electrolyte:

1 ml of nitric acid, 150 ml of ethylene glycol solution and 150 ml of glycerol solution were added to 200 ml of purified water, and the mixture was uniformly mixed and used. Example 4:

Follow the steps below to prepare the electrolyte:

10 ml of nitric acid, 50 ml of ethylene glycol solution and 40 ml of glycerol solution were added to 400 ml of purified water, and the mixture was uniformly mixed. Example 5:

Providing an electrolytic cell, the solution prepared in Example 2 is added into the electrolytic cell as an electrolytic solution, and the stent body pretreated in Example 1 is placed in the electrolytic cell as an anode, after the voltage is 30-40 V, and the reaction is 120 s, A metal stent having a surface micropore diameter and a pore depth of Ο. ΐ μηι ~ 2μηι was obtained. Example 6:

Providing an electrolytic cell, the solution prepared in Example 3 is added into the electrolytic cell as an electrolyte, and the stent body pretreated in Example 1 is placed as an anode in the electrolytic cell at a voltage of

10~30V, after 60s reaction, a metal scaffold with a surface pore diameter of 2μηι ~5μηι and a pore depth of Ι μηι ~5μηι was obtained. Example 7

Providing an electrolytic cell, the solution prepared in Example 4 is added into the electrolytic cell as an electrolyte solution, and the stent body pretreated in Example 1 is placed in the electrolytic cell as an anode, and the voltage is 2 to 10 V, and after 5 seconds of reaction, A metal stent having a surface micropore diameter of 5 μm to 10 μm and a pore depth of 2 μm to 10 μm was obtained. Example 8:

Add 100 mg of rapamycin to 10 ml of acetone, mix well, and set aside. Example 9

The stent bodies with micropores on the surface obtained in Example 6 and Example 7 were respectively immersed in the drug solution obtained in Example 8, sonicated for 10 minutes, and taken out to dry, thereby obtaining a human body lumen drug-loading stent. The above description is only a preferred embodiment of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be In the case of God or range, it is implemented in other embodiments. Therefore, the application is not limited to the embodiments shown herein, but the broadest scope consistent with the principles and novel features disclosed herein.

Claims

Claim

A metal stent, comprising a stent body, wherein a plurality of holes are evenly distributed on an outer peripheral surface of the stent body, and an inner surface of the stent body is a smooth surface.

2. The metal bracket according to claim 1, wherein the bracket body has a tubular mesh shape.

The metal bracket according to claim 1, wherein the hole has a hole diameter and a hole depth of 0.1 μm to 10 μm.

4. The metal stent according to claim 1, wherein the metal stent is a human intraluminal stent.

The metal stent according to claim 1 , wherein the material of the stent body is stainless steel, cobalt-based alloy, nickel-based alloy, titanium alloy or degradable magnesium alloy with good biocompatibility and mechanical properties. .

The metal stent according to claim 4, wherein the human intraluminal stent comprises: a coronary artery stent, an intracranial blood vessel stent, a peripheral blood vessel stent, a splenic artery stent, an intraoperative stent, and a heart valve. Stent, biliary stent, esophageal stent, intestinal stent, pancreatic duct stent, urethral stent or tracheal stent.

A method of preparing a metal stent, comprising:

Pre-treating the surface of the stent body to remove impurities on the surface of the stent body; adding an electrolyte to the electrolytic cell, the electrolyte comprising 0.02%-10% nitric acid; using the pre-treated stent body as an anode An electrochemical corrosion reaction is performed in the electrolyte to obtain a metal stent having a plurality of pores uniformly distributed on the outer peripheral surface.

8. The method of claim 7, wherein the pre-treating comprises: polishing, washing, and/or drying.

9. The method of claim 7, wherein the electrolyte further comprises:

0.01% ~ 100% ethylene glycol solution and / or 0.01% ~ 100% glycerol solution.

10. The method according to claim 7, wherein the electrochemical corrosion reaction has a reaction voltage of 2 to 40 V and a reaction time of 5 to 300 s.

1 1. A human body lumen drug-carrying stent, comprising a stent body, wherein a plurality of holes are uniformly distributed on an outer circumferential surface of the stent body, and the plurality of holes are filled with a drug, and the stent body is The inner surface is a smooth surface.

12. The human lumen drug-loading stent according to claim 11, wherein the drug comprises: an anti-inflammatory drug, an anti-platelet drug, an anticoagulant, an anticancer drug, an immunosuppressive agent, a hormone One or more.

A method for preparing a human body lumen drug-loading stent, comprising: pretreating a surface of the stent body to remove impurities on a surface of the stent body; and adding an electrolyte to the electrolytic cell, wherein the electrolyte solution comprises 0.02%~10% nitric acid; using the pretreated pretreated stent body as an anode, performing electrochemical corrosion reaction in the electrolyte to obtain a stent body having a plurality of holes on the outer peripheral surface;

Dissolving the drug in an organic solvent to obtain a drug solution;