Addressing Societal-scale Challenges with Nanoscale Materials: Flexible, Impedance-sensing “Smart Bandages” Enable Early Detection of Pressure Wounds

By Sarah Swisher

Electrical Engineering and Computer Science, University of California, Berkeley, CA

View Presentation

Additional materials available (4)

Licensed under General Performance Usage.

Published on


In parallel with the continued scaling of traditional CMOS devices, another paradigm of electronics has taken shape: flexible electronic systems. Flexible displays, electronic textiles, bio-inspired sensors, and wearable or implantable medical devices are just a few applications that benefit from large-area form factors and mechanical flexibility, both of which are challenging to achieve with conventional wafer-based electronics. In this talk, I will introduce our work developing solution-processed materials for flexible electronics, with emphasis on how these materials will enable new applications. I will then focus on one example: our recent development of a “smart bandage” prototype for detecting and monitoring tissue wounds in vivo.

Pressure ulcers are formed when pressure is applied to a localized area of the body for an extended period of time, resulting in reduced blood flow and cell death. Preventing pressure ulcers is challenging because the combination of pressure and time that results in permanent tissue damage can vary widely between patients, and the underlying tissue damage is often severe by the time a surface wound becomes visible. We have developed a flexible, electronic device that non-invasively maps pressure-induced tissue damage, even when such damage cannot bevisuallyobserved. Employing impedance spectroscopy across flexible electrode arrays in vivo on a rat model, we find that the frequency spectra of impedance measurements are correlated in a robust way with the state of the underlying tissue across multiple animals and wound types. Tissue damage detected using the impedance sensor is represented visually as a wound map, identifying regions at risk of developing a pressure ulcer and thus enabling intervention. These results demonstrate the feasibility of an automated, non-invasive “smart bandage” for early monitoring and diagnosis of pressure ulcers, improving patient care and outcomes.


image Sarah Swisher received her BS in Electrical Engineering from the University of Nebraska-Lincoln in 2004. Upon graduation, Sarah spent several years as the lead electrical design engineer for a series of GPS-enabled bicycle computers at Garmin, Intl. She received her MS in Electrical Engineering from the University of California, Berkeley in 2012, and will receive her PhD in the same in 2015 under the guidance of Prof. Vivek Subramanian. Her research has focused on the synthesis, characterization, and application of solution-processed electronic materials. Sarah was recognized at UNL with the College of Engineering and Technology Outstanding Achievement Award and the Outstanding Senior Award in Electrical Engineering, and she received the EECS Chair's Excellence Award from UC Berkeley. Sarah has been awarded the National Science Foundation Graduate Research Fellowship, the UC Berkeley Graduate Division Mentored Research Fellowship, and the Intel Foundation Noyce Memorial Fellowship in Microelectronics.

Sponsored by

Cite this work

Researchers should cite this work as follows:

  • Sarah Swisher (2015), "Addressing Societal-scale Challenges with Nanoscale Materials: Flexible, Impedance-sensing “Smart Bandages” Enable Early Detection of Pressure Wounds,"

    BibTex | EndNote


Birck Nanotechnology Center, Rm 1001, Purdue University, West Lafayette, IN