Biohybrid Microrobots Show Promise in Repairing Spinal Cord Injuries
Researchers at ETH Zurich and the University of Zurich have developed a novel biohybrid microrobot, dubbed the NPCbot. This device combines neural progenitor cells derived from induced pluripotent stem cells with magnetoelectric nanoparticles. These nanoparticles convert external magnetic fields into electrical signals, enabling minimally invasive stimulation of stem cell differentiation.
Significant Results in Animal Models
- Zebrafish larvae with spinal cord injuries: Following injection of the NPCbot and application of an electromagnetic field, the larvae exhibited near-normal swimming and exploratory behavior within just three days.
- Mice with completely severed spinal cords: After 28 days of treatment, nerve cells reconnected at the injury site. Treated mice showed marked improvements in gait, stride length, coordination, and exploratory behavior. Critically, no adverse effects or immune reactions were observed.
Mechanism and Key Advantages
The core innovation lies in the elimination of implanted electrodes. By using external magnetic fields for electrical stimulation, the approach is far less invasive. The nanoparticles themselves are coated with barium titanate, ensuring stability and low biological reactivity. Researchers will continue to study the long-term degradation or excretion pathways of these particles.
Scalable Production
The NPCbots are fabricated on a compact lab-on-a-chip system (just 1 cm²) in approximately 30 minutes. Production is easily scaled by running multiple chips in parallel, allowing for the manufacture of hundreds of thousands of units for cell studies and millions for animal experiments.
Next Steps and Broader Applications
Further research is required before human testing can begin, specifically to determine the optimal parameters for the magnetic field and the ideal duration of stimulation. However, the platform is adaptable and may eventually be applied to other fields, including cardiology, oncology, and wound healing.