Reconfigurable Magnetic Soft Microrobot for Acoustically Triggered Targeted Bacterial Sterilization

By: Quan Gao, Fan Li, Jiajie Gao, Elric Zhang, Yingdong Su, Ni Qin, Hao Ye, Josep Puigmartí,

Giuseppe Cantarella, Simone Schuerle, Jiang Wu, Bradley J. Nelson, and Salvador Pané

Several nanomaterials have been proposed for antibacterial applications,offering promising strategies to combat infections as antibiotic resistancecontinues to rise due to widespread misuse. However, their clinical translation remains limited by poor localization and the lack of active control at the target site. Here, a thermoresponsive, shape-reconfigurable hydrogel-based magnetic microrobot is presented that addresses these challenges by integrating piezoelectric zinc oxide (ZnO) nanorods directly onto its soft, dynamic surface. The nanorods are densely grown in situ, enabling localized, acoustically triggered bacterial sterilization. The reconfigurability of the microrobot provides functional versatility: in its swollen, helical state, embedded magnetic nanoparticles allow effective magnetic maneuvering in fluidic environments. When heated above the swelling–deswelling transition temperature, the robot flattens to increase surface contact, enhancing interaction with biological targets. Under ultrasound stimulation, the ZnO nanorods undergo mechanical bending, triggering piezocatalysis and generating reactive oxygen species near the target site. This multifunctional platform combines active navigation, dynamic shape change, and localized antibacterial action, offering a new strategy for integrating functional nanomaterials into soft, reconfigurable devices with future therapeutic potential.

Link to publication: https://zenodo.org/records/19183421