(595f) Delivery and Actuation of Aerosolized Microbots

Pulmonary drug delivery is commonly performed using inhalers which disperse µm-scale droplets throughout the lungs. However, once delivered, drug transport can be diffusion-limited and impeded by mucous build-up, especially in cystic fibrosis patients. In addition, inhalation-based therapies cannot selectively target within the lungs to treat localized diseases, such as cancer. Microbots show good promise for overcoming these issues; however, microbots are typically fabricated in sizes greater than the optimal droplet size for inhalation-based deposition in the lung. Here, we present a novel microbot delivery system that uncouples size from structure and function by delivering colloidal paramagnetic building blocks into the lungs for assembly in situ to form microwheels capable of translation, selective delivery, and mechanical work deep within lung mimics. To verify beads are successfully loaded, aerosolized bead-laden droplets are captured in oil to determine loading and size distributions. Aerosolized microwheel velocity distributions are measured and are not significantly different after delivery. Clear 3D-printed lung mimics are fabricated to demonstrate two targeting methods; one which generally drives microwheels deeper, and one which selectively targets specific areas. Together, this work opens the previously inaccessible pulmonary system for inhalation-based microbot therapies.