MOF-Functionalized Ultrasound-Trackable Magnetic Microrobots for Intracranial Toxin Removal

Toxin accumulation within specialized microenvironments, such as cerebrospinal fluid (CSF), poses significant clinical challenges. In particular, bilirubin in CSF can cause severe damage to the brain and neural tissues. Current therapeutic strategies for intracranial bilirubin clearance suffer from poor targeting, inadequate detoxification capacity, and reliance on invasive procedures. Here, we demonstrate multifunctional microrobots designed for toxin removal in specialized anatomical compartments. The proposed ultrasound-trackable microbubbles@PCN-333 microrobots (UMPCs) feature a hollow hydrogel microbubble core for enhanced ultrasound imaging contrast, an outer metal-organic framework (MOF) layer for proactive and high-capacity toxin adsorption, and embedded ferroferric oxide (Fe₃O₄) nanoparticles to enablec. Magnetic actuation enhances the UMPC's bilirubin capture efficiency through improved mass transfer. By integrating an ultrafast ultrasound imaging system with magnetic actuation, we achieve real-time tracking and precise control of UMPCs within the CSF. This strategy offers a minimally invasive and actively guided approach for efficient intracranial bilirubin clearance, opening new avenues for targeted toxin-removal in anatomically confined environments.