My research covers multiple disciplines including materials science, molecular engineering, and biomedical engineering. Through innovations in material design and device fabrication, my past research has led to several breakthroughs in the field of bioelectronics, including non-genetic optical control of biological activities through rationally designed multiscale silicon structures, localized neuromodulation of organ-specific activities through intrinsically stretchable conducting polymers, and closed-loop wound care through wireless bioelectronic systems. For my future research, I will continue to transform breakthroughs in physical sciences and engineering into novel tools to address unmet medical needs.
inorganic semicoNductors for remote biomodulation
Optically controlled nongenetic biomodulation represents a promising approach for investigation of fundamental biological questions and application in clinical settings. Among existing material candidates that can transduce light energy into biologically relevant cues, silicon is particularly advantageous due to its highly tunable electrical and optical properties, ease of fabrication into multiple forms, ability to absorb a broad spectrum of light, and biocompatibility. Using bottom-up chemical synthesis, I built a full library of silicon-based inorganic semiconducting materials with unique photo-responses and demonstrated an array of novel biological applications using non-genetic optical modulation of calcium dynamics, neuronal excitability, and animal behaviors (Nature Materials, 2016; Nature Biomedical Engineering, 2018, Science Advances, 2020).
Bottom-up synthesis of mesostructured semicoNductors
Semiconductors with three-dimensional (3D) mesoscale feature are an emerging class of materials. However, progress in this area has been impeded by challenges in 3D fabrication methods. Utilizing advanced characterization techniques to guide the bottom-up chemical synthesis, I prepared a range of 3D silicon mesostructures and elucidated the underlying physicochemical processes that shape the structures and properties down to atomic-scale precision (Science, 2015; Nature Communications, 2017; Nano Letters, 2018).
Soft and Stretchable organic bioelectronics
Intrinsically stretchable bioelectronic devices based on soft and conducting organic materials have been regarded as the ideal interface for seamless and biocompatible integration with the human body. Through a novel molecular engineering strategy based on topological supramolecular network, my research solved a longstanding challenge in the field of organic bioelectronics by achieving simultaneously high mechanical robustness and good electrical conduction for conducting polymers at cellular level feature sizes. I further developed an intrinsically stretchable high-density electrode array that allows cellular-scale mapping of electrophysiological activities of soft-bodied octopus and precise neuromodulation of organ-specific activities through brainstem down to single nucleus precision (Science, 2022). Additionally, I developed a battery-free flexible bioelectronic system for chronic wound management. Using multiple pre-clinical models, I demonstrated the capability of our wound care system to continuously monitor wound physiological conditions and to trigger directional electrical stimulation for accelerated tissue regeneration.