Catheters navigating through complex vessels,such as sharp turns or multiple U-turns,remain challenging for vascular embolization.Here,we propose a novel multistage vascular embolization strategy for hard-to-reach ves...Catheters navigating through complex vessels,such as sharp turns or multiple U-turns,remain challenging for vascular embolization.Here,we propose a novel multistage vascular embolization strategy for hard-to-reach vessels that releases untethered swimming shape-memory magnetic microrobots(SMMs)from the prior catheter to the vessel bifurcation.SMMs,made of organo-gel with magnetic particles,ensure biocompatibility,radiopacity,thrombosis,and fast thermal and magnetic responses.An SMM is initially a linear shape with a 0.5-mm diameter at 20°C inserted in a catheter.It transforms into a predetermined helix within 2 s at 38°C blood temperature after being pushed out of the catheter into the blood.SMMs enable agile swimming in confined and tortuous vessels and can swim upstream using helical propulsion with rotating magnetic fields.Moreover,we validated this multistage vascular embolization in living rabbits,completing 100-cm travel and renal artery embolization in 2 min.After 4 weeks,the SMMs maintained the embolic position,and the kidney volume decreased by 36%.展开更多
基金the National Key Research and Development Project under Grant 2023YFB4705300in part by the National Natural Science Foundation of China under Grant U22A2064+3 种基金in part by the Youth Innovation Promotion Association of CASin part by the Shenzhen Science and Technology Program under Grant JCYJ20220818101611025in part by the Guangdong Basic and Applied Basic Research Foundation(2022B1515120010)and in part by SIAT-CUHK Joint Laboratory of Robotics and Intelligent Systems.
文摘Catheters navigating through complex vessels,such as sharp turns or multiple U-turns,remain challenging for vascular embolization.Here,we propose a novel multistage vascular embolization strategy for hard-to-reach vessels that releases untethered swimming shape-memory magnetic microrobots(SMMs)from the prior catheter to the vessel bifurcation.SMMs,made of organo-gel with magnetic particles,ensure biocompatibility,radiopacity,thrombosis,and fast thermal and magnetic responses.An SMM is initially a linear shape with a 0.5-mm diameter at 20°C inserted in a catheter.It transforms into a predetermined helix within 2 s at 38°C blood temperature after being pushed out of the catheter into the blood.SMMs enable agile swimming in confined and tortuous vessels and can swim upstream using helical propulsion with rotating magnetic fields.Moreover,we validated this multistage vascular embolization in living rabbits,completing 100-cm travel and renal artery embolization in 2 min.After 4 weeks,the SMMs maintained the embolic position,and the kidney volume decreased by 36%.