Nanofiber reinforced absorbable intravascular stent and preparation method thereof

Abstract

The invention discloses a nanofiber reinforced absorbable intravascular stent which is made of a medical nanofiber reinforced composite material; the medical nanofiber reinforced composite material comprises a basic material and nano short-staple, and the nano short-staple keeping at a crystal morphology disperses in the basis material. According to the nanofiber reinforced absorbable intravascular stent, the wall thickness thereof is reduced to be about 100 micrometers, that is reduced by about 30% as compared with the wall thickness of the existing stent, and thus, influence to blood vesselsfrom the stent is reduced, quantity of polymer and acid degradation products is decreased, and risk of thrombus is reduced; as the basic material of the nanofiber reinforced material contains fewer ester bonds, in other words, there is one ester bond every five to six carbon atoms, content of carboxyl is reduced and acidity is decreased greatly as compared with that of Poly-L-lactide after degradation, risk of adverse reaction is much lower, and safety performance is higher.

Description

technical field [0001] The invention relates to the technical field of vascular stents, in particular to a nanofiber-reinforced absorbable vascular stent and a preparation method thereof. Background technique [0002] Vascular stent refers to the placement of internal stents in the diseased segment on the basis of lumen balloon expansion to achieve the purpose of supporting the stenotic and occluded segment of the vessel, reducing the elastic retraction and reshaping of the vessel, and maintaining the smooth blood flow in the lumen. Internal stents also have the function of preventing restenosis, mainly divided into coronary stents, cerebrovascular stents, renal artery stents and aortic stents; according to the absorbability of the prepared materials, they are divided into non-absorbable vascular stents and absorbable vascular stents Vascular stents are usually metal stents, which exist permanently after use and affect CT and other examinations. Stents cannot be re-implanted...

AI Technical Summary

Problems solved by technology

[0002] Vascular stent refers to the placement of internal stents in the diseased segment on the basis of lumen balloon expansion to achieve the purpose of supporting the stenotic and occluded segment of the vessel, reducing the elastic retraction and reshaping of the vessel, and maintaining the smooth blood flow in the lumen. Internal stents also have the function of preventing restenosis, mainly divided into coronary stents, cerebrovascular stents, renal artery stents and aortic stents; according to the absorbability of the prepared materials, they are divided into non-absorbable vascular stents and absorbable vascular stents Vascular stents are usually metal stents, which exist permanently after use and affect CT and other examinations. Stents cannot be re-implanted in stenotic areas. At the same time, patients need to take anticoagulant drugs for life, which has a greater potential risk; absorbable vascular stents include absorbable stents. Metals (mainly magnesium alloys, iron alloys, etc.) and degradable polyesters, among which absorbable metals have problems such as uncontrollable degradation rate, uneven degradation and risk of accumulation of metal ions, while the existing degradable polyesters mostly use poly-L-propylene Lactide, this type of stent material has poor elasticity, is not easy to compress and transport, is not easy to operate during use, and cannot completely fit the soft inner wall of the blood vessel, and the wall thickness of the stent is generally more than 150 μm, and the risk of thrombosis after implantation is relatively high. Due to the high content of ester bonds in poly-L-lactide (there is one ester bond for every two carbons), the content of carboxyl groups after degradation is more, and the resulting acidity is likely to cause inflammation and the potential risk of restenosis

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