title: CNT/PDMS composite flexible dry electrodes for long-term ECG monitoring.
abstract: We fabricated a carbon nanotube (CNT)/ polydimethylsiloxane (PDMS) composite-based dry ECG electrode that can be readily connected to conventional ECG devices, and showed its long-term wearable monitoring capability and robustness to motion and sweat. While the dispersion of CNTs in PDMS is challenging, we optimized the process to disperse untreated CNTs within PDMS by mechanical force only. The electrical and mechanical characteristics of the CNT/PDMS electrode were tested according to the concentration of CNTs and its thickness. The performances of ECG electrodes were evaluated by using 36 types of electrodes which were fabricated with different concentrations of CNTs, and with a differing diameter and thickness. The ECG signals were obtained by using electrodes of diverse sizes to observe the effects of motion and sweat, and the proposed electrode was shown to be robust to both factors. The CNT concentration and diameter of the electrodes were critical parameters in obtaining high-quality ECG signals. The electrode was shown to be biocompatible from the cytotoxicity test. A seven-day continuous wearability test showed that the quality of the ECG signal did not degrade over time, and skin reactions such as itching or erythema were not observed. This electrode could be used for the long-term measurement of other electrical biosignals for ubiquitous health monitoring including EMG, EEG, and ERG.
authors.affiliation: Department of Biomedical Engineering, College of Health Science, Korea University, Seoul 136-703, Korea. hacher99@korea.ac.kr
authors.forename: Ha-Chul
authors.initials: HC
authors.lastname: Jung
authors.forename: Jin-Hee
authors.initials: JH
authors.lastname: Moon
authors.forename: Dong-Hyun
authors.initials: DH
authors.lastname: Baek
authors.forename: Jae-Hee
authors.initials: JH
authors.lastname: Lee
authors.forename: Yoon-Young
authors.initials: YY
authors.lastname: Choi
authors.forename: Joung-Sook
authors.initials: JS
authors.lastname: Hong
authors.forename: Sang-Hoon
authors.initials: SH
authors.lastname: Lee
mesh_terms: D000328:Adult; D003020:Clothing; D004129:Dimethylpolysiloxanes / Q000009:adverse effects / Q000737:chemistry*; D004562:Electrocardiography / Q000295:instrumentation* / Q000379:methods; D004566:Electrodes; D005260:Female; D006801:Humans; D008297:Male; D008422:Materials Testing; D018670:Monitoring, Ambulatory / Q000295:instrumentation*; D037742:Nanotubes, Carbon / Q000009:adverse effects / Q000737:chemistry*
chemical_list: D004129:Dimethylpolysiloxanes; D037742:Nanotubes, Carbon; C013830:baysilon