Shell-core structure degradable stent and preparation method thereof

Abstract

The invention discloses a shell-core structure degradable stent and a preparation method thereof. The stent is tubular in structure and comprises a tent body; the stent body has a skeleton and a hollow structure formed in the skeleton. The skeleton comprises an inner shell layer having a hollow tubular shape; a hollow tubular intermediate core layer coated outside the inner shell layer, the intermediate core layer comprising an outer core layer and a core layer of a network structure coated inside the outer core layer; and a hollowed-out tubular outer shell layer coated outside the intermediate core layer; the inner core layer is a polymer polylactic acid having a molecular weight of 700-800 kDa and the outer core layer is a high molecular polylactic acid having a molecular weight of 200-300 kDa. The shell-core structure degradable stent is convenient for spraying and sacculus clamping processing, and no stent wire breakage occurs during and after the processing, which greatly reducesthe processing difficulty and the risk of stent breakage under the condition of ensuring good degradability of the degradable stents.

Description

technical field [0001] The invention belongs to the technical field of medical devices, and relates to a degradable bracket, in particular to a degradable bracket with a shell-core structure and a preparation method thereof. Background technique [0002] Stent implantation is an important means of common clinical treatment of ischemic cardiovascular disease, but the third-generation metal drug-eluting stent is still commonly used in the market. The stent material includes 316L stainless steel, cobalt-chromium alloy and titanium alloy. Wait. Once this metal stent is implanted, it will be accompanied by foreign body and vascular tissue for life, and patients usually need to take antiplatelet drugs for a long time to prevent thrombosis. In addition, metal stents stimulate the blood vessel wall for a long time, leading to vascular endothelial dysfunction, resulting in local chronic inflammation and excessive proliferation of new tissue, which can easily form in-stent restenosis...

AI Technical Summary

Problems solved by technology

[0009] The purpose of the present invention is to address the defect that a single polymer cannot take into account mechanical properties, degradable properties and processability in the prior art, and propose a degradable scaffold with a shell-core structure that can satisfy both mechanical properties and degradable properties and its preparation method

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