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bioRxiv · 10.1101/2025.09.29.679200

Self-Propelling Adaptive Robotic Microcatheters Enabled by Scalable Fabrication for Intracorporeal Navigation

Chen, Z.·Rivkin, B.·Castellanos-Robles, D.·Soldatov, I.·Beyer, L.·Medina Sanchez, M.
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Abstract

Minimally invasive therapies demand precise navigation through complex and delicate anatomical pathways, requiring medical tools that are small, flexible, and highly maneuverable. Here, we present a scalable fabrication platform for magnetic tubular microrobots, tethered and untethered, with programmable magnetization, enabling self-propulsion, and an adaptive remote control for targeted interventions. The platform uses Joule heating through a template wire for rapid, and reliable fabrication of microrobots with tunable dimensions. We demonstrate three device configurations: (1) a steerable guiding microcatheter with stiffness modulation; (2) an untethered tubular microrobot (TubeBot) exhibiting wave-crawling locomotion; and (3) a hybrid microcatheter robot that integrates distal-end wave-crawling propulsion with linear insertion to minimize tissue trauma. Validation in tortuous channels, soft phantoms replicating tissue compliance, 3D-printed organ models, ex vivo tissues, and live mice demonstrates the platforms ability to achieve precise microrobotic navigation. The successful targeted delivery of sperm cells, embryos, and drug-mimicking compounds further highlights its potential for precision medicine, including applications in assisted reproduction and targeted drug delivery.

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Chen, Z., Rivkin, B., Castellanos-Robles, D., Soldatov, I., Beyer, L., Medina Sanchez, M.. 2025-09-30. Self-Propelling Adaptive Robotic Microcatheters Enabled by Scalable Fabrication for Intracorporeal Navigation. https://doi.org/10.1101/2025.09.29.679200

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