BME PhD Defense Announcement for Ángel G. Enríquez Mujica (H. Lee, advisor) Everyone is invited to attend the public presentation beginning at 9:00 am. Title: Magnetic actuators for applications in biomedical devices and a novel thrombectomy catheter Date: April 13th Time: 9:00 am Location: MJIS 2001 and Zoom: https://purdue-edu.zoom.us/j/98595923252 ; Meeting ID: 985 9592 3252 Thesis Committee: Hyowon (Hugh) Lee (Major professor), Luis Solorio, Chi-Hwan Lee, Daniel Sahlein Abstract: The untethered transfer of energy and the scalability of magnetic actuators can add novel functionalities to an otherwise passive system. For example, wireless magnetic actuation can turn static 2D and 3D cell cultures into a more physiologically-relevant dynamic environment that can limit contamination. Moreover, magnetic microactuators can turn conventionally static indwelling catheters and implantable sensors with limited functional lifespan into more active and reliable medical devices. In this work, I will demonstrate examples of novel biomedical microdevices enabled by magnetic actuation. First, I will describe a soft polymer magnetic actuator that can facilitate the study of a physiologically relevant cell culturing system. By cyclically stretching an extracellular matrix protein in a 3D cell culture, this system can elucidate the process by which breast cancer cells respond to a dynamic environment in the lungs. Our results demonstrate a clear suppression of cancer cell progression due to cyclic stretching that has implications for a mechanical role in the dormancy and reactivation of metastasizing breast cancer cells. As a second application, I will demonstrate the use of magnetic microactuators to regenerate biosensors to prolong their functionality. Our preliminary results suggest that the motion of the actuator on the sensor surface can maintain biosensor signal integrity and prevents the downstream effects of the foreign body response. Finally, I will present the design and proof of concept testing of a novel aspiration thrombectomy catheter meant to improve the engagement between the catheter and the blood clot being removed. Our preliminary results demonstrate the added benefit of incorporating a microstructure in an aspiration catheter lumen with increased embolism retraction force.