Modular magnetic microrobots achieve precision drug delivery

A magnetically guided microrobotics system is capable of navigating the body's intricate passageways and vasculature to deliver drugs with pinpoint accuracy, according to a new study. The novel system could enable safer, targeted drug treatments that minimize unwanted side effects. Systemic drug treatments often cause unwanted side effects due to off-target exposure and account for nearly one-third of failures in clinical trials, illustrating the need for precise, targeted drug delivery strategies.

To address this, researchers have worked to develop magnetic micro- and nanorobots designed to deliver drugs directly to diseased tissues. Advances in materials science, fabrication, and control systems have enabled microrobots capable of complex movement and targeted delivery in complex biological environments. However, bridging these technologies into clinical practice remains challenging, as it requires the seamless integration of locomotion, navigation, drug delivery, and imaging functions into a single platform while also ensuring the use of biocompatible, biodegradable materials.

Building on their previous work, Fabian Landers and colleagues present a modular magnetically guided, microrobotic platform that integrates an electromagnetic navigation system (Navion) with a custom release catheter and drug-loaded, dissolvable capsule. Each nontethered gelatin-based microrobot contains magnetic and radiopaque nanoparticles along with therapeutic agents, allowing it to be precisely guided to a target site within the body while being tracked in real-time via X-ray imaging. After use, the microrobot can be triggered to dissolve safely within the body.

Landers et al. tested the platform in vitro using human vasculature models and in vivo in sheep and pigs under realistic clinical conditions to demonstrate the system's capabilities. By applying specific magnetic fields, the authors show that the system can maneuver through complex blood vessels and cerebrospinal spaces, trigger controlled heating to dissolve the microrobot and precisely release drugs into targeted tissues, even reaching the smallest vessels. "Although significant work remains to fully translate this technology into clinical practice, our results provide a robust framework for addressing the complex challenges associated with targeted drug delivery," Landers et al. write.