Simple fabrication of helical-shaped microrobot with NdFeB nanoparticle by self-rolling technique

The fabrication of a medical microrobot with wireless control will allow the device to enhance its accessibility to reach small targets and complex environments in human body. Here, we provide a simple and versatile method to fabricate the helical-shaped microrobot based on self-rolling techniques. We first prepared the UV curable magnetic ink by mixing the photoresist material, E-dent 400 (FDA approved), and permanent magnet, NdFeB nanoparticles, and then patterned the microrobot using an infinity-corrected optical system. The microrobot can be self-rolled to form the helical shape and be steered using electromagnetic actuation (EMA) system. This study demonstrated a simple and efficient strategy to fabricate magnetically driven microrobots with a hollow-helical structure.