The Purdue team’s work is published in the journal Advanced Materials.

“The PVA-based TENGs show great potential for self-powered biomedical devices and open doors to new technologies that use widely deployed biocompatible materials for economically feasible and ecologically friendly production of functional devices in energy, electronics and sensor applications,” said Wenzhuo Wu, the Ravi and Eleanor Talwar Rising Star Assistant Professor of Industrial Engineering in Purdue’s College of Engineering, who led the development team. “We transform PVA, one of the most widely used polymers for biomedical applications, into wearable, self-powered triboelectric devices which can detect the imperceptible degree of skin deformation induced by human pulse and capture the cardiovascular information encoded in the pulse signals with high fidelity.”

Cardiovascular health is typically measured by echocardiogram to measure electrical activity in the heart or photoplethysmography that measures changes in blood volume in the peripheral microvasculature.

“These technologies can often be invasive to patients and have not yet been adapted into wearables for personalized on-demand monitoring,” Wu said. “TENGs with PVA blend contact layers produce fast readout with distinct peaks for blood ejection, blood reflection in the lower body, and blood rejection from the closed aortic valve, which may enable detection of common cardiovascular diseases such as cardiovascular disease, coronary artery disease and ischemic heart disease.”

Wu said PVA offers a valuable opportunity as potential constituents in future wearable self-powered devices. The PVA-based triboelectric devices can harvest the mechanical energy from the human body and use such electric power to support the operations of other biomedical devices.

Wu said the PVA-based triboelectric devices can function as self-powered sensors to detect and monitor the mechanical activities from the human body in applications such as health monitoring, human-machine interface, teleoperated robotics, consumer electronics and virtual and augmented technologies.

The team worked with the Purdue Research Foundation Office of Technology Commercialization to patent the technology.

The creators are looking for partners to commercialize their technology. For more information on licensing this innovation or other inventions from Wu’s team, contact Matt Halladay of OTC at MRHalladay@prf.org and reference track code 2020-WU-69052.

About Purdue Research Foundation Office of Technology Commercialization

Writer: Chris Adam, 765-588-3341, cladam@prf.org

Source: Wenzhuo Wu, wu966@purdue.edu

Abstract

Holistically Engineered Polymer-Polymer and Polymer-Ion Interactions in Biocompatible Polyvinyl Alcohol Blends for High-Performance Triboelectric Devices in Self-Powered Wearable Cardiovascular Monitoring

Ruoxing Wang, Liwen Mu, Yukai Bao, Han Lin, Tuo Ji, Yijun Shi, Jiahua Zhu and Wenzhuo Wu

The capability of sensor systems to efficiently scavenge their operational power from stray, weak environmental energies through sustainable pathways could enable viable schemes for selfpowered health diagnostics and therapeutics. Triboelectric nanogenerators (TENG) can effectively transform the otherwise wasted environmental, mechanical energy into electrical power. Recent advances in TENGs have resulted in a significant boost in output performance. However, obstacles hindering the development of efficient triboelectric devices based on biocompatible materials continue to prevail. Being one of the most widely used polymers for biomedical applications, polyvinyl alcohol (PVA) presents exciting opportunities for biocompatible, wearable TENGs. Here, the holistic engineering and systematic characterization of the impact of molecular and ionic fillers on PVA blends’ triboelectric performance is presented for the first time. Triboelectric devices built with optimized PVAgelatin composite films exhibit stable and robust triboelectricity outputs. Such wearable devices can detect the imperceptible skin deformation induced by the human pulse and capture the cardiovascular information encoded in the pulse signals with high fidelity. The gained fundamental understanding and demonstrated capabilities enable the rational design and holistic engineering of novel materials for more capable biocompatible triboelectric devices that can continuously monitor vital physiological signals for selfpowered health diagnostics and therapeutics.