A Printed Organic Amplification System for Wearable Potentiometric Electrochemical Sensors

• Published in: Scientific reports Vol. 8; no. 1; pp. 3922 - 8
• Main Authors: Shiwaku, Rei, Matsui, Hiroyuki, Nagamine, Kuniaki, Uematsu, Mayu, Mano, Taisei, Maruyama, Yuki, Nomura, Ayako, Tsuchiya, Kazuhiko, Hayasaka, Kazuma, Takeda, Yasunori, Fukuda, Takashi, Kumaki, Daisuke, Tokito, Shizuo
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 02.03.2018; Nature Publishing Group
• Subjects: 639/166/987; 639/301/923/3931; Biocompatibility; Circuits; Data processing; Humanities and Social Sciences; multidisciplinary; Potassium; Science; Science (multidisciplinary); Sensors; Signal processing
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-018-22265-1

Electrochemical sensor systems with integrated amplifier circuits play an important role in measuring physiological signals via in situ human perspiration analysis. Signal processing circuitry based on organic thin-film transistors (OTFTs) have significant potential in realizing wearable sensor devices due to their superior mechanical flexibility and biocompatibility. Here, we demonstrate a novel potentiometric electrochemical sensing system comprised of a potassium ion (K + ) sensor and amplifier circuits employing OTFT-based pseudo-CMOS inverters, which have a highly controllable switching voltage and closed-loop gain. The ion concentration sensitivity of the fabricated K + sensor was 34 mV/dec, which was amplified to 160 mV/dec (by a factor of 4.6) with high linearity. The developed system is expected to help further the realization of ultra-thin and flexible wearable sensor devices for healthcare applications.