Study on the chronic toxicity and carcinogenicity of iron-based bioabsorbable stents

Fe-based stents have been made a figure in biodegradable stents by their good mechanical capacity and biocompatibility, appropriate strength–ductility combination. Although the iron corrosion rate was not ideal, which had been optimized by iron alloy and polymer coating introduction. As a long-term implanted biodegradable material, the real concern about iron-based stents mainly laid in long-term biosafety. In this work, rats were used as an animal model to study the chronic toxicity and carcinogenicity of iron-based stents. Two years later, the changes in body weight and the physiological status during the experiment were monitored, and the blood routine and blood analysis combined with the health of major organs and histopathological tests were performed. The results demonstrated that there was no significant difference compared with the control group (316L SS) in body weight, blood routine index, blood biochemical index, and carcinogenic rate that further confirmed the biosafety of iron-based material.