Thermally reduced graphene oxide-nylon membrane based epidermal sensor using vacuum filtration for wearable electrophysiological signals and human motion monitoring. (March 2020)

• Record Type: Journal Article
• Authors: Das, Partha Sarati; Park, Sang Hyun; Baik, Ku Youn; Lee, Jang Woo; Park, Jae Yeong
• Is Part Of: Carbon. Volume 158(2020)
• Page Start: 386
• Page End: 393
• Publication Date: 2020-03
• Subjects: EEG -- ECG -- EMG -- Epidermal sensor -- TRGO -- Biocompatible -- Ag/AgCl -- Strain -- Tension -- Compression; Carbon -- Periodicals; Carbone -- Périodiques; Koolstof; Toepassingen; Electronic journals; 546.681
• DOI: 10.1016/j.carbon.2019.11.001
• Languages: English
• ISSNs: 0008-6223

Abstract

Abstract: We fabricated high-performance paper-based epidermal sensors on biocompatible nylon-membrane without utilizing any harmful chemicals & complicated processes. The proposed epidermal sensor was fabricated using thermally reduced graphene oxide and a nylon-membrane (TRGO/NM). The epidermal sensor (TRGO/NM) has been developed to reduce the usage of Ag/AgCl (sticky sensor). The sensor demonstrates high sensitivity (sheet resistance = 40 Ω/sq.), because skin-contact impedance was ∼20KΩ at low frequency. We found that the TRGO/NM sensor developed micro-gaps on the surface of NM, which generated resistance changes under tensile and compressive strain. The TRGO/NM sensor shows fast response time (∼0.5 s), relaxation time (∼0.5 s), and a highly stable with an excellent bending-stretching response. We applied the epidermal sensor for obtaining electrocardiography (ECG), electroencephalography (EEG), and electromyography (EMG) as well as monitoring human motions also. The biocompatibility of the TRGO/NM sensor was confirmed by performing the cytotoxicity test. Graphical abstract: Image 1 Highlights: A low-cost and simple method to fabricate thermally reduced graphene oxide and nylon-membrane (TRGO/NM) based biocompatible dry sensors for bioelectric measurements is presented. The fabricated sensor was attached perfectly on top of the epidermis layer. As a result, the contact impedance of the epidermis layer-sensor interface was low and stable. The TRGO/NM sensor showed no cytotoxicity, implying that it can be utilized for a lengthy-time, unlike Ag/AgCl sensors. This TRGO/NM based flexible dry paper sensor exhibits good electrical performance, flexibility, reusability, biocompatibility, and wearability.