A Multifunctional Wearable Device with a Graphene/Silver Nanowire Nanocomposite for Highly Sensitive Strain Sensing and Drug Delivery

Ge Shi,Yu Lin Zhong,Allison Cowin,Zlatko Kopecki,Sean E Lowe,Tianqing Liu,Ivan Lee,Jing-Hong Pai

doi:10.3390/c5020017

Abstract

Advances in wearable, highly sensitive and multifunctional strain sensors open up new opportunities for the development of wearable human interface devices for various applications such as health monitoring, smart robotics and wearable therapy. Herein, we present a simple and cost-effective method to fabricate a multifunctional strain sensor consisting of a skin-mountable dry adhesive substrate, a robust sensing component and a transdermal drug delivery system. The sensor has high piezoresisitivity to monitor real-time signals from finger bending to ulnar pulse. A transdermal drug delivery system consisting of polylactic-co-glycolic acid nanoparticles and a chitosan matrix is integrated into the sensor and is able to release the nanoparticles into the stratum corneum at a depth of ~60 µm. Our approach to the design of multifunctional strain sensors will lead to the development of cost-effective and well-integrated multifunctional wearable devices.

Highlights

Wearable electronic devices have attracted considerable attention in recent years [1,2,3]
We have developed a novel multifunctional wearable strain sensor comprised of a skin-mountable dry adhesive substrate, a sensing component and a transdermal drug delivery system
The sensing part consisted of layered graphene nanoplatelets and silver nanowires that displayed high piezoresisitivity for monitoring real-time motion signals, such as finger bending and radial pulse

Summary

Introduction

Wearable electronic devices have attracted considerable attention in recent years [1,2,3]. Skin-mountable strain sensors have potential applications in personal health monitoring, human motion detection and smart human–machine interaction [4,5,6]. These sensors often consist of two components: a stimuli-responsive component and a stretchable substrate. The stimuli-responsive component should possess high durability, sensitivity and stretchability, while the substrate should be capable of forming robust and conformal interactions with biological skin. For skin-mountable devices, substrates employing traditional medical tapes or elastic films generally have limited stretchability and usage times [7,8]. A promising alternative is represented by dry adhesive substrates with a fibrillary hierarchical structure [9]

Methods

Results

Conclusion