Biliary stent

Abstract

The application relates to the field of metal nanopowder or plasma spraying, and particularly discloses a biliary stent prepared by combining metal nanopowder with a plasma spraying process. The ZrNbFeLa coating prepared by the plasma spraying process has good corrosion resistance, but the hemolysis rate is poor. Further, a proper amount of metal Ti is injected into the ZrNbFeLa coating, so that the biocompatibility of the ZrNbFeLa coating can be significantly improved, the corrosion resistance is not greatly affected, and the ZrNbFeLa coating can meet the use requirements of medical materials such as the biliary stent. It should be noted that the ion injection amount of the metal Ti needs to be controlled within 2.8*10 5 ions / cm 2 -1.2*10 12 ions / cm 2 , otherwise, too much titanium will cause the corrosion resistance of the ZrNbFeLa coating to sharply decrease.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of metal nanopowder (B22F9 / 08) or plasma spraying (C23C4 / 134), in particular to a biliary stent prepared by using metal nanopowder combined with plasma spraying process. BACKGROUND

[0002] The biliary stent is a tubular medical device, mainly used for the treatment of biliary stricture or obstruction caused by various reasons. Its core function is to restore the normal flow of bile, thereby relieving symptoms (such as jaundice, itching, abdominal pain) and preventing complications (such as cholangitis).

[0003] In the prior art, metal materials are often used to manufacture biliary stents. However, the corrosion resistance of metal materials is poor, which seriously affects the service life of the biliary stent. At the same time, as a medical material, the biocompatibility of the biliary stent is also an important performance that cannot be ignored. Therefore, there is an urgent need to design a biliary stent medical material that takes into account corrosion resistance and biocompatibility. SUMMARY

[0004] The purpose of the present application is to provide a biliary stent prepared by using metal nanopowder combined with plasma spraying process, which has good corrosion resistance and biocompatibility.

[0005] The technical solution of the present application is as follows:

[0006] A biliary stent prepared by using metal nanopowder combined with plasma spraying process, the preparation process of the biliary stent includes the following steps:

[0007] Metal nanopowder material prepared by atomization method: equal molar amounts of zirconium powder, niobium powder, iron powder and lanthanum powder are uniformly mixed and placed in a smelting furnace for smelting; the obtained metal melt is introduced into a preheated tundish; the metal melt is caused to flow out of the nozzle of the tundish and, under a protective atmosphere, a metal nanopowder material is obtained by atomization method;

[0008] Substrate pretreatment: select the biliary stent material as the substrate, use 8-12wt% HCl solution to remove the oxide layer on the surface of the substrate, then clean it in deionized water and dry it for use;

[0009] Plasma spraying: the metal nanopowder material is coated onto the surface of the substrate by using plasma spraying process. During the spraying process, the working voltage is 40-45V, the working current is 300-320A, the powder carrying gas rate is 30-35L / min, the powder feeding rate is 20-25g / min, and the spraying distance is 8-9cm;

[0010] Ion implantation of metal Ti: the substrate is placed into a metal vapor vacuum arc power ion implantation device, and metal Ti is implanted into the surface of the plasma sprayed ZrNbFeLa coating, the implantation amount of metal ions is 2.8*10 5 ions / cm 2 -1.2*10 12 ions / cm 2 .

[0011] Preferably, the concentration of the HCl solution is 12wt%.

[0012] Preferably, the working voltage is 40V.

[0013] Preferably, the working current is 300A.

[0014] Preferably, the powder carrying gas rate is 30L / min.

[0015] Preferably, the powder feeding rate is 25g / min.

[0016] Preferably, the spraying distance is 9cm.

[0017] The ZrNbFeLa coating prepared by the plasma spraying process has good corrosion resistance, but the hemolysis rate is poor. Further implanting an appropriate amount of metal Ti into the ZrNbFeLa coating can significantly improve its biocompatibility, and has little effect on corrosion resistance, thereby meeting the use requirements of bile duct stents and other medical materials. It should be noted that the ion implantation amount of metal Ti needs to be controlled within 2.8*10 5 ions / cm 2 -1.2*10 12 ions / cm 2 , otherwise, too much titanium will cause the corrosion resistance of the ZrNbFeLa coating to decrease sharply. DETAILED DESCRIPTION

[0018] The technical effects of the present application will be verified by specific examples below, but the embodiments of the present application are not limited thereto.

[0019] Example 1

[0020] Metal nanometer powder material prepared by atomization method: equal molar amounts of zirconium powder, niobium powder, iron powder and lanthanum powder are uniformly mixed and placed into a smelting furnace for smelting; the obtained metal melt is introduced into a preheated tundish; the metal melt is caused to flow out of the nozzle of the tundish and obtained by atomization method under a protective atmosphere;

[0021] Substrate pretreatment: choose the bile duct stent material as the substrate, select 8wt% HCl solution to remove the oxide layer on the surface of the substrate, then clean in deionized water and dry for use;

[0022] Plasma spraying: adopt plasma spraying process to coat the metal nano-powder material to the surface of the substrate, during the spraying process, the working voltage is 40V, the working current is 300A, the powder carrying gas rate is 30L / min, the powder feeding rate is 20g / min, and the spraying distance is 8cm;

[0023] Ion implantation of metal Ti: put the substrate into the metal vapor vacuum arc power ion implantation equipment, implant metal Ti to the surface of the plasma sprayed ZrNbFeLa coating, the implantation amount of metal ions is 2.8*10 5 ions / cm 2 .

[0024] Example 2

[0025] Preparation of metal nano-powder material by atomization method: mix equal molar amounts of zirconium powder, niobium powder, iron powder and lanthanum powder uniformly, put them into a smelting furnace for smelting; introduce the obtained metal melt into a preheated tundish; make the metal melt flow out of the nozzle of the tundish and obtain the metal nano-powder material by atomization method under a protective atmosphere;

[0026] Substrate pretreatment: choose the bile duct stent material as the substrate, select 8wt% HCl solution to remove the oxide layer on the surface of the substrate, then clean in deionized water and dry for use;

[0027] Plasma spraying: adopt plasma spraying process to coat the metal nano-powder material to the surface of the substrate, during the spraying process, the working voltage is 40V, the working current is 300A, the powder carrying gas rate is 30L / min, the powder feeding rate is 20g / min, and the spraying distance is 8cm;

[0028] Ion implantation of metal Ti: put the substrate into the metal vapor vacuum arc power ion implantation equipment, implant metal Ti to the surface of the plasma sprayed ZrNbFeLa coating, the implantation amount of metal ions is 3.2*10 6 ions / cm 2 .

[0029] Example 3

[0030] Preparation of metal nano-powder material by atomization method: mix equal molar amounts of zirconium powder, niobium powder, iron powder and lanthanum powder uniformly, put them into a smelting furnace for smelting; introduce the obtained metal melt into a preheated tundish; make the metal melt flow out of the nozzle of the tundish and obtain the metal nano-powder material by atomization method under a protective atmosphere;

[0031] Substrate pretreatment: choose the bile duct stent material as the substrate, select 8wt% HCl solution to remove the oxide layer on the surface of the substrate, then clean in deionized water and dry for use;

[0032] Plasma spraying: adopt plasma spraying process to coat the metal nano-powder material to the surface of the substrate, in the spraying process, the working voltage is 40V, the working current is 300A, the powder carrying gas rate is 30L / min, the powder feeding rate is 20g / min, and the spraying distance is 8cm;

[0033] Ion implantation of metal Ti: put the substrate into the metal vapor vacuum arc power ion implantation equipment, implant metal Ti to the surface of the plasma sprayed ZrNbFeLa coating, the implantation amount of metal ions is 5.4×10 8 ions / cm 2 .

[0034] Example 4

[0035] Preparation of metal nano-powder material by atomization method: mix equal molar amounts of zirconium powder, niobium powder, iron powder and lanthanum powder uniformly, put them into a smelting furnace for smelting; introduce the obtained metal melt into a preheated tundish; make the metal melt flow out of the nozzle of the tundish and obtain the metal nano-powder material by atomization method under a protective atmosphere;

[0036] Substrate pretreatment: choose the bile duct stent material as the substrate, select 8wt% HCl solution to remove the oxide layer on the surface of the substrate, then clean in deionized water and dry for use;

[0037] Plasma spraying: adopt plasma spraying process to coat the metal nano-powder material to the surface of the substrate, in the spraying process, the working voltage is 40V, the working current is 300A, the powder carrying gas rate is 30L / min, the powder feeding rate is 20g / min, and the spraying distance is 8cm;

[0038] Ion implantation of metal Ti: put the substrate into the metal vapor vacuum arc power ion implantation equipment, implant metal Ti to the surface of the plasma sprayed ZrNbFeLa coating, the implantation amount of metal ions is 6.5×10 10 ions / cm 2 .

[0039] Example 5

[0040] Preparation of metal nano-powder material by atomization method: mix equal molar amounts of zirconium powder, niobium powder, iron powder and lanthanum powder uniformly, put them into a smelting furnace for smelting; introduce the obtained metal melt into a preheated tundish; make the metal melt flow out of the nozzle of the tundish and obtain the metal nano-powder material by atomization method under a protective atmosphere;

[0041] Substrate pretreatment: choose the bile duct stent material as the substrate, select 8wt% HCl solution to remove the oxide layer on the surface of the substrate, then clean in deionized water and dry for use;

[0042] Plasma spraying: adopt plasma spraying process to coat the metal nano-powder material to the surface of the substrate, during the spraying process, the working voltage is 40V, the working current is 300A, the powder carrying gas rate is 30L / min, the powder feeding rate is 20g / min, and the spraying distance is 8cm;

[0043] Ion implantation of metal Ti: place the substrate into the metal vapor vacuum arc power ion implantation equipment, implant metal Ti to the surface of the plasma sprayed ZrNbFeLa coating, the implantation amount of metal ions is 1.2×10 12 ions / cm 2 .

[0044] Comparative example 1

[0045] Preparation of metal nano-powder material by atomization method: uniformly mix equal molar amounts of zirconium powder, niobium powder, iron powder and lanthanum powder, put them into a smelting furnace for smelting; introduce the obtained metal melt into a preheated tundish; make the metal melt flow out of the nozzle of the tundish and obtain the metal nano-powder material by atomization method under a protective atmosphere;

[0046] Substrate pretreatment: choose the bile duct stent material as the substrate, select 8wt% HCl solution to remove the oxide layer on the surface of the substrate, then clean in deionized water and dry for use;

[0047] Plasma spraying: adopt plasma spraying process to coat the metal nano-powder material to the surface of the substrate, during the spraying process, the working voltage is 40V, the working current is 300A, the powder carrying gas rate is 30L / min, the powder feeding rate is 20g / min, and the spraying distance is 8cm.

[0048] Comparative example 2

[0049] Preparation of metal nano-powder material by atomization method: uniformly mix equal molar amounts of zirconium powder, niobium powder, iron powder and lanthanum powder, put them into a smelting furnace for smelting; introduce the obtained metal melt into a preheated tundish; make the metal melt flow out of the nozzle of the tundish and obtain the metal nano-powder material by atomization method under a protective atmosphere;

[0050] Substrate pretreatment: choose the bile duct stent material as the substrate, select 8wt% HCl solution to remove the oxide layer on the surface of the substrate, then clean in deionized water and dry for use;

[0051] Plasma spraying: metal nano-powder material is coated onto the surface of the substrate by using a plasma spraying process. During the spraying process, the working voltage is 40 V, the working current is 300 A, the powder carrying gas rate is 30 L / min, the powder feeding rate is 20 g / min, and the spraying distance is 8 cm.

[0052] Ion implantation of metal Ti: the substrate is placed into a metal vapor vacuum arc power ion implantation device, and metal Ti is implanted into the surface of the plasma sprayed ZrNbFeLa coating. The implantation amount of metal ions is 3.6 x 10 15 ions / cm 2 .

[0053] In the following, the corrosion resistance and biocompatibility of the samples in Examples 1-5 and Comparative Examples 1-2 are evaluated. In order to ensure the comparability of the samples in each group, the process conditions other than the implantation amount of Ti are ensured to be exactly the same during the experiment. The experimental results are shown in Table 1.

[0054] Table 1: Experimental data of each sample

[0055]

[0056] As can be seen from Table 1, the ZrNbFeLa coating prepared by the plasma spraying process of the present application has good corrosion resistance, but the hemolysis rate is poor. Further implanting an appropriate amount of metal Ti into the ZrNbFeLa coating can significantly improve its biocompatibility, and has little effect on the corrosion resistance, thereby meeting the use requirements of bile duct stents and other medical materials. It should be noted that the implantation amount of metal Ti should be controlled at 2.8 x 10 5 ions / cm 2 -1.2 x 10 12 ions / cm 2 , otherwise, too much titanium will cause the corrosion resistance of the ZrNbFeLa coating to decrease sharply.

[0057] The above description is only the preferred embodiments of the present application, and it should be noted that for ordinary skilled persons in the art, several improvements and modifications can be made without departing from the technical principles of the present application, and these improvements and modifications should also be considered as the protection scope of the present application.

Claims

1. A biliary stent prepared by a plasma spray process using metal nanopowder, characterized in that, The preparation process of the biliary stent comprises the following steps: The metal nano-powder material is prepared by atomization method: equal-molar amounts of zirconium powder, niobium powder, iron powder and lanthanum powder are uniformly mixed and put into a smelting furnace for smelting; the obtained metal melt is introduced into a preheated tundish; the metal melt is caused to flow out of the nozzle of the tundish and, under a protective atmosphere, the metal nano-powder material is obtained by atomization method; Substrate pretreatment: select the biliary stent material as the substrate, use an 8-12wt% HCl solution to remove the oxide layer on the surface of the substrate, then clean it in deionized water and dry it for use; Plasma spraying: the metal nano-powder material is coated onto the surface of the substrate by plasma spraying process, during the spraying process, the working voltage is 40-45V, the working current is 300-320A, the powder carrying gas rate is 30-35L / min, the powder feeding rate is 20-25g / min, and the spraying distance is 8-9cm; Ion implantation of metal Ti: The substrate was placed into a metal vapor vacuum arc power ion implantation device, and metal Ti was implanted into the surface of the plasma sprayed ZrNbFeLa coating at an implantation amount of 2.8 x 1014 ions / cm 5 . 2 - 1.2 x 1014 ions / cm 12 2 .​ 2. The biliary stent of claim 1, wherein, The concentration of the HCl solution is 12wt%.

3. The biliary stent of claim 1, wherein, The working voltage is 40V.

4. The biliary stent of claim 1, wherein, The working current is 300A.

5. The biliary stent of claim 1, wherein, The powder carrying gas rate is 30L / min.

6. The biliary stent of claim 1, wherein, The powder feeding rate is 25g / min.

7. The biliary stent of claim 1, wherein, The spraying distance is 9cm.

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