Ultrafine Molybdenum Wire Braided Neurointerventional Implants: Bridging Biodegradability and Neurovascular Safety for Stroke Treatment

Abstract Neurovascular implants for stroke intervention face a critical dilemma: permanent devices (e.g., nitinol stents, platinum coils) often trigger chronic inflammation and recurrence, whereas biodegradable alternatives (Mg, Fe, Zn alloys) lack radiopacity or raise neurotoxicity concerns. Here, we introduce φ50 µm molybdenum (Mo) wire braided implants that integrate procedural efficacy with biological safety. Mo demonstrates negligible hemolysis (<5%), platelet‐inert surfaces, and preserved coagulation kinetics, together with robust cytocompatibility across neurovascular unit cells (endothelia, astrocytes, neurons) under both physiological and ischemia–reperfusion conditions. In vivo, Mo stent wires implanted in rodent carotids maintained blood homeostasis, organ integrity, and neurological function without systemic toxicity. Moreover, braided 2D Mo coils achieved durable aneurysm occlusion with controlled inflammatory resolution and progressive endothelialization, closely resembling clinical performance. Importantly, Mo ions showed no detectable accumulation in brain, kidney, lung, or spleen, attributable to renal clearance and blood–brain barrier selectivity. By coupling intrinsic radiopacity with homogeneous, moderate corrosion, Mo addresses long‐standing limitations of existing biodegradable alloys. These findings position Mo as a transformative candidate for next‐generation neurovascular devices, harmonizing biodegradability, safety, and imaging precision to redefine the management of both ischemic and hemorrhagic stroke.