Long-span delivery of differentiable hybrid robots for restoration of neural connections

Lumbar puncture is a minimally invasive technique for delivering drugs into cerebrospinal fluid (CSF). However, its effectiveness is limited by the spine’s extensive length and the narrow, complex CSF spaces, which hinder efficient passive diffusion of therapeutic agents. Here, we have engineered a differentiable stem cell-assembled soft robot (SCASR) by using a three-dimensional self-assembly process in liquid marbles. These biologically viable robots can interface with the tissues inside the CSF, adapting to the complex surroundings while navigating. With X-ray imaging and magnetic actuation, the SCASRs can be guided toward targeted regions. The SCASRs autonomously disassemble into individual cells, which then differentiate into neural cells to facilitate the restoration of neural connections, thereby aiding the recovery of paralyzed lower limbs. The proposed strategy provides an imaging-based therapeutic system for nerve injury, enabling accessibility of hard-to-reach spinal regions and facilitating efficient therapy in minimally invasive manner, by means of soft microrobots.