New generation of medical implants: Metallic biodegradable coronary stent

Abstract

Biodegradable stent is considered as an innovative approach to treat coronary artery occlusion. It is expected to provide scaffolding function during the healing period and progressively disappear thereafter leaving no foreign remnant in the vessel. Progress on biodegradable stents depends on the development of their constitutive materials, including degradable metals. Currently, the main challenge is to optimize mechanical property and degradation behavior of the proposed metals. This work aims to develop new metal alloy for biodegradable stents having physical and mechanical property approaching those of 316L stainless steel but with degradation capability. The alloy is composed of iron and 35wt%manganese and was produced through a powder sintering process. This Fe35Mn alloy possesses comparable mechanical property to that of 316L stainless steel. Its degradation rate is slightly faster than pure iron but slower than magnesium alloy. The alloy shows moderate toxicity effect to fibroblast cells. Finally, the alloy was successfully transformed into stent prototype using standard fabrication protocol for 316L stainless steel and shows appropriate mechanical performance.