Conformal skin bioelectronics for portable 3-lead ECG

• Main Author: Wang, Ruijie
• Other Authors: Chen Xiaodong
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2023
• Subjects: Engineering::Materials::Biomaterials
• Online Access: https://hdl.handle.net/10356/166582
• Institution: Nanyang Technological University

As healthcare systems worldwide face resource limitations, governments and research institutes are investing more into preventative healthcare initiatives. In this regard, conformal bioelectronics hold a significant advantage over conventional bulky and rigid equipment in terms of portability and user experience. However, the lack of mature flexible electronics ecosystem is a limiting factor for their development. To address the mechanical property mismatch between rigid microelectronic components, flexible substrates, and human tissue, a technique to unify these materials cohesively is urgently required to provide a reliable platform for future innovation. In contrast to various proposed methodologies, this project presents screen-printing of electronic circuits using silver electronic paste for fabricating conformal wearable devices. This study demonstrated the feasibility and benefits (simplicity, versatility and scalability) of this approach by fabricating a 3-lead ECG bilayer circuit on a PDMS substrate. The resulting product was thin, comfortable, and imperceptibly transparent whilst conforming tightly to the epidermis. Preliminary characterization presented high resolution patterns with low contact resistance at ±2Ω and negligible variance in width modulation for fine prints at sub-millimetre scale. By incorporating viaholes in the circuit design, multilayer circuits can be fabricated to fit multiple functions in a small area. In summary, this research serves as a feasibility study for initiating the development of novel flexible bioelectronics with broad applications, particularly for monitoring biophysiological signals.