| Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2016) | |
| Biomaterial Surfaces & Interfaces | Tuesday Sessions |
| Session BI-TuE |
| Session: | Medical Applications |
| Presenter: | Takanari Saito, Tokyo University of Agriculture & Technology, Japan |
| Authors: | T. Saito, Tokyo University of Agriculture & Technology, Japan Y. Kihara, Tokyo University of Agriculture & Technology, Japan J. Shirakashi, Tokyo University of Agriculture & Technology, Japan |
| Correspondent: | Click to Email |
Recently, wearable health-monitoring devices based on strain sensors have been widely applied in disease diagnosis and health assessment. Various flexible materials, including polymer nanofibers [1], nanowires [2], carbon nanotubes [3], and graphene [4], have high flexibility and sensitivity, and are good potential candidates for the wearable health-monitoring devices. However, the fabrications of the wearable devices are, in many cases, complicated multistep procedures which result in the waste of materials and require expensive facilities. Therefore, we focused on a commercially available pyrolytic graphite sheet (PGS) [5] which is an inexpensive and an artificial flexible graphite sheet. Previously, we have reported that thin graphite films are simply and easily fabricated from PGSs, and are used as wearable strain sensors for monitoring human motions [6, 7]. In this study, we investigated the application of wearable devices based on the thin graphite films for wrist pulse monitoring.
First, the thin graphite films were fabricated by cutting small films from 17-µm-thick PGSs. Then, the thin graphite films were cleaved onto adhesive tapes using the mechanical exfoliation method. Finally, the thin graphite films were wired using silver conducting paste for electrical measurements. The thin graphite films used as strain sensors were attached over the radial artery to monitor the wrist pulse. The peaks of the resistance waveform were periodically observed, and therefore the wrist pulse was successfully detected using these devices. The results suggest that the thin graphite films could be applied as cost-effective health monitoring devices for human physiological signals.
References
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[5] Pyrolytic Graphite Sheet Product Datasheet, Panasonic Industrial Devices, Japan.
[6] T. Saito, H. Shimoda, and J. Shirakashi, J. Vac. Sci. Technol. 33 (2015) 042002.
[7] T. Saito, Y. Kihara, and J. Shirakashi, IC-MAST 2016 (6th International Conference on Materials and Applications for Sensors and Transducers), September 27-30, 2016, Athens, Greece.