Bile duct stent

Abstract

The invention relates to the field of metal nanopowder or plasma spraying, and particularly discloses a bile duct stent prepared by combining metal nanopowder with a plasma spraying process, and a ZrNbFeLa coating prepared by the plasma spraying process has good corrosion resistance but is poor in hemolysis rate. Furthermore, a proper amount of metal Ti is injected into the ZrNbFeLa coating, so that the biocompatibility of the ZrNbFeLa coating can be remarkably improved, and the influence on the corrosion resistance is small, so that the ZrNbFeLa coating can meet the use requirements of medical materials such as bile duct stents. It needs to be noted that the ion implantation amount of metal Ti needs to be controlled to be 2.8 * 10 < 5 > ions / cm < 2 > to 1.2 * 10 < 12 > ions / cm < 2 >, otherwise, the corrosion resistance of the ZrNbFeLa coating can be sharply reduced due to excessive titanium.

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: A biliary stent prepared by using metal nanopowder combined with plasma spraying process, the preparation process of the biliary stent comprises the following steps: Preparation of metal nanopowder 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 nanopowder material by atomization method under a protective atmosphere; 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; Plasma spraying: use plasma spraying process to coat the metal nanopowder material on the surface of the substrate, 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: put the substrate into the metal vapor vacuum arc power ion implantation equipment, implant metal Ti into the surface of the ZrNbFeLa coating layer, and the implantation amount of metal ions is 2.8×10 5 ions / cm 2-1.2 x 10 12 ions / cm 2 .

[0006] Preferably, the concentration of the HCl solution is 12wt%.

[0007] Preferably, the working voltage is 40V.

[0008] Preferably, the working current is 300A.

[0009] Preferably, the powder carrying gas rate is 30L / min.

[0010] Preferably, the powder feeding rate is 25g / min.

[0011] Preferably, the spraying distance is 9cm.

[0012] The ZrNbFeLa coating prepared by the plasma spraying process has good corrosion resistance, but the hemolysis rate is poor. Further injecting 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 injection amount of metal Ti needs to 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. DETAILED DESCRIPTION

[0013] 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.

[0014] Example 1 Metal nano-powder 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 nano-powder material is obtained by atomization method; Substrate pretreatment: select bile duct stent material as substrate, use 8wt% HCl solution to remove the oxide layer on the surface of the substrate, then clean in deionized water and dry for use; Plasma spraying: the metal nano-powder material is coated onto the surface of the substrate by plasma spraying process, and 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; 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 being 2.8 x 10 5 ions / cm 2 .

[0015] Example 2 Preparation of metal nanopowder material 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, under a protective atmosphere, metal nanopowder material is obtained by atomization method; Substrate pretreatment: a bile duct stent material is selected as the substrate, an 8wt% HCl solution is used to remove the oxide layer on the surface of the substrate, and then the substrate is cleaned in deionized water and dried for use; Plasma spraying: the metal nanopowder material is coated onto the surface of the substrate by plasma spraying process, 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; 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 being 3.2 x 10 6 ions / cm 2 .

[0016] Example 3 Preparation of metal nanopowder material 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, under a protective atmosphere, metal nanopowder material is obtained by atomization method; Substrate pretreatment: a bile duct stent material is selected as the substrate, an 8wt% HCl solution is used to remove the oxide layer on the surface of the substrate, and then the substrate is cleaned in deionized water and dried for use; Plasma spraying: the metal nanopowder material is coated onto the surface of the substrate by plasma spraying process, 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; 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 being 5.4 x 10 8 ions / cm 2 .

[0017] Example 4 Preparation of metal nanopowder material 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, metal nanopowder material is obtained by atomization method; Substrate pretreatment: a bile duct stent material is selected as the substrate, an 8wt% HCl solution is used to remove the oxide layer on the surface of the substrate, and then the substrate is cleaned in deionized water and dried for use; Plasma spraying: the metal nanopowder material is coated onto the surface of the substrate by plasma spraying process, 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; Ion implantation of metal Ti: the substrate is placed into a metal vapor vacuum arc power ion implantation device, metal Ti is implanted onto the surface of the plasma sprayed ZrNbFeLa coating, and the implantation amount of metal ions is 6.5×10 10 ions / cm 2 .

[0018] Example 5 Preparation of metal nanopowder material 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, metal nanopowder material is obtained by atomization method; Substrate pretreatment: a bile duct stent material is selected as the substrate, an 8wt% HCl solution is used to remove the oxide layer on the surface of the substrate, and then the substrate is cleaned in deionized water and dried for use; Plasma spraying: the metal nanopowder material is coated onto the surface of the substrate by plasma spraying process, 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; Ion implantation of metal Ti: the substrate is placed into a metal vapor vacuum arc power ion implantation device, metal Ti is implanted onto the surface of the plasma sprayed ZrNbFeLa coating, and the implantation amount of metal ions is 1.2×10 12 ions / cm 2 .

[0019] Comparative Example 1 Preparation of metal nano-powder material 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 metal nano-powder material is obtained by atomization method under a protective atmosphere; Substrate pretreatment: a bile duct stent material is selected as the substrate, an 8wt% HCl solution is selected to remove the oxide layer on the surface of the substrate, and then the substrate is cleaned in deionized water and dried 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 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.

[0020] Comparative Example 2 Preparation of metal nano-powder material 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 metal nano-powder material is obtained by atomization method under a protective atmosphere; Substrate pretreatment: a bile duct stent material is selected as the substrate, an 8wt% HCl solution is selected to remove the oxide layer on the surface of the substrate, and then the substrate is cleaned in deionized water and dried 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 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. Ion implantation of metal Ti: the substrate is put into a metal vapor vacuum arc power ion implantation device, metal Ti is implanted into the surface of the ZrNbFeLa coating layer, and the implantation amount of metal ions is 3.6x10 15 ions / cm 2 .

[0021] In the following, the corrosion resistance and biocompatibility of the test 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 ion implantation amount of Ti are ensured to be exactly the same during the experiment, and the experimental results are shown in Table 1.

[0022] Table 1 Experimental data of each sample As can be seen from Table 1, the ZrNbFeLa coating prepared by the plasma spraying process has good corrosion resistance, but the hemolysis rate is poor. Further injecting an appropriate amount of metal Ti into the ZrNbFeLa coating can significantly improve the biocompatibility thereof, has little effect on the corrosion resistance, and thus meets the use requirements of medical materials such as bile duct stents. It should be noted that the ion injection 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.

[0023] The above only describes the preferred embodiments of the present application, and it should be noted that, for those skilled in the art, without departing from the technical principles of the present application, a number of improvements and modifications can be made, and these improvements and modifications should also be considered as the protection scope of the present application.

Claims

1. A bile duct stent prepared using metal nanopowder combined with plasma spraying process, characterized in that, The preparation process of the biliary stent includes the following steps: Preparation of metal nanopowder materials by atomization method: Equimolar amounts of zirconium powder, niobium powder, iron powder, and lanthanum powder are uniformly mixed and placed in a melting furnace for melting; the obtained molten metal is introduced into a preheated tundish; the molten metal flows out from the nozzle of the tundish, and metal nanopowder materials are obtained by atomization under a protective atmosphere; Substrate pretreatment: Select biliary stent material as substrate, use 8-12wt% HCl solution to remove the oxide layer on the surface of substrate, then wash in deionized water and dry for later use; Plasma spraying: The plasma spraying process is used to coat metal nanopowder materials onto the surface of the substrate. During the spraying process, the working voltage is 40-45V, the working current is 300-320A, the powder carrier gas rate is 30-35L / min, the powder feeding rate is 20-25g / min, and the spraying distance is 8-9cm. Ion implantation of metallic Ti: The substrate is placed in a metal vapor vacuum arc ion implantation device, and metallic Ti is implanted into the surface of the plasma-sprayed ZrNbFeLa coating. The implantation amount of metal ions is 2.8 × 10⁻⁶. 5 ions / cm 2 -1.2×10 12 ions / cm 2 .

2. A bile duct stent as described in claim 1, characterized in that, The concentration of the HCl solution is 12 wt%.

3. A bile duct stent as described in claim 1, characterized in that, The operating voltage is 40V.

4. A bile duct stent as described in claim 1, characterized in that, The operating current is 300A.

5. A bile duct stent as described in claim 1, characterized in that, The powder-carrying gas rate is 30 L / min.

6. A bile duct stent as described in claim 1, characterized in that, The powder feeding rate is 25 g / min.

7. A bile duct stent as described in claim 1, characterized in that, The spraying distance is 9cm.

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