UCLA

Stable bioelectronic interfaces require functional materials to accommodate the complex geometry, continuous deformation, and dynamic mechanical environment of biological tissues. Conventional solid bioelectronics improve conformability primarily through material softening and structural engineering, but its adaptability remains fundamentally constrained by predefined device geometries and deformation of solid functional components. Here, this dissertation introduces liquid magneto-viscoelastic materials as an intrinsically reconfigurable material platform for conformal bioelectronics, in which fluidic rearrangement, magnetic interactions, and reversible phase transitions are exploited to integrate mechanical adaptability with sensing, energy transduction, and therapeutic functionality.Liquid magneto-viscoelastic materials were first engineered for ultrasound-to-electrical energy conversion. Their tissue-matched acoustic impedance (~1.66 MRayl) minimizes interfacial reflection, while ultrasound-induced translational and rotational dynamics of field-organized magnetic nanoparticles generate time-varying magnetic flux for electromagnetic induction. This mechanism enables programmable transducer geometries and wireless bioelectrical stimulation across cardiovascular and neural interfaces. Extending material reconfigurability to spatial control, a bioinspired ingestible transducer combines magnetic-fluid energy conversion with programmed soft-magnetic actuation, enabling navigation across complex gastrointestinal surfaces and subsequent wireless electrical stimulation at relocatable anatomical sites. To further reconcile liquid-state adaptability with operational stability, a thermos-reversible carrageenan-based magneto-viscoelastic composite was developed with tunable phase-transition temperatures near physiological conditions. The material can be patterned directly on irregular biological surfaces in its liquid state, solidified in situ to establish stable and highly conformal interfaces, and reversibly liquefied for material recovery. Conductive and magnetic functionalization further enables electrophysiological recording and biomechanical sensing.Together, these studies establish a material-centered strategy in which bioelectronic interfaces are not merely mechanically softened, but can reconfigure their geometry, spatial location, functional state, and material lifecycle, providing a foundation for adaptive, relocatable, and sustainable bioelectronics.