When
Friday, October 9, 2026, at 12:00 p.m.
David Clausen and Kareem Hussein
Doctoral Candidates
Department of Biomedical Engineering
University of Arizona
Meinel 103 | Zoom link
David Clausen
"Out of Sight, Always On: Advanced Biosignal Monitoring with Biosymbiotic Electronics"
Abstract:
Modern wearable technology increasingly requires enhanced biomarker specificity and user-burden minimization. Adhesive-based sensors fail from skin turnover, battery-driven paradigms require perpetual recharge cycles, and biochemical sensors foul easily and are often invasive. This work develops platforms that address each concern in turn. First, 3D-printed conductive TPU dry electrodes are integrated into textiles to record clinical-grade Electrocardiogram (ECG) in periods of work, exercise, and sleep, as well as a skin-conformal biosymbiotic platform showing the first chronic-scale evaluation of Electrical Impedance Myography (EIM) modulation in response to strength training. These platforms eliminate long-term monitoring concerns associated with electrophysiology captured via gel Ag/AgCl electrodes. Secondly, diffusion-based gas sensing measures gas emitted from skin without biofluid contact, resolving sweat rate without device replacement second by second over more than five days, impossible in previous platforms. Additionally, the platform enables capture of skin CO2 and Volatile Organic Compounds (VOC) linked to metabolic changes associated with exercise, alcohol consumption, stress and more. Purpose-built research devices like those above achieve high biosignal specificity but often lack broad translatability. Disseminating wearable technology at scale requires a cost-effective and near-instant production capacity, which we demonstrate using zinc oxide–doped TPU filaments for multimodal sensing. Importantly, we illustrate compatibility with injection molding and advanced manufacturing techniques, providing a path to low-cost, large-scale manufacture of biosymbiotic platforms.
Kareem Hussein
"Decoding Sensory and Motor Intent Signals Recorded by Y-shaped Regenerative Microelectrode Arrays"
Abstract:
For a decade, the number of people losing their limbs has grown to almost 58 million globally. The majority are lower limb amputees with access to advanced prosthetics embedded with mechanical, motion and muscle sensors and predefined gait algorithms to move. However, they cannot fully control or feel the bionic leg as their own. This is due, in part, to the heterogeneous mixture of peripheral nerves whose motor and sensory fibers innervate to specific muscles and receptors, which disappear after amputation. This results in a challenge to electrically stimulate specific sensory fibers to restore those lost sensations. To address this, researchers have developed peripheral nerve interfaces over the last two decades. Previous studies have revealed unintended consequences of stimulating multiple sensory fibers simultaneously to convey a specific sensation, requiring the need for improved selectivity. Here, we walk through particular strategies to separate the fibers and selectively interface them using a Y-shaped conduit, populating one chamber with more sensory fibers and one chamber with more motor. With this re-engineered neural interface, from device design, fabrication and electrode characterization to in vivo testing, we report the results of decoded sensory and motor command signals from chronically implanted microelectrodes, highlighting the clear separation between these unique neural signals and what this means for amputees interfacing neuroprosthetic limbs.