US EPA

3975611 

Journal Article 

Sensitive and Fast Humidity Sensor Based on A Redox Conducting Supramolecular Ionic Material for Respiration Monitoring 

Yan, H; Zhang, L; Yu, P; Mao, L 

2017 

Yes 

Analytical Chemistry
ISSN: 0003-2700
EISSN: 1520-6882 

89 

1 

996-1001 

English 

28105832 

10.1021/acs.analchem.6b04350 

WOS:000391346600094 

Real-time monitoring of respiratory rate (RR) is highly important for human health, clinical diagnosis, and fundamental scientific research. Exhaled humidity-based RR monitoring has recently attracted increased attention because of its accuracy and portability. Here, we report a new design of an exhaled humidity sensor for the real-time monitoring of the RR based on a synthetic redox conducting supramolecular ionic material (SIM). The humidity-dependent conducting SIM is prepared by ionic self-assembly in aqueous solutions of electroactive 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 1,10-bis(3-methylimidazolium-1-yl) decane (C10(mim)2). By taking full advantage of the high hygroscopicity and water stability arising from the ionic and hydrophobic interactions between two building blocks (i.e., ABTS and C10(mim)2), the SIM-based humidity sensor exhibits both high sensitivity (less than 0.1% relative humidity) and fast response time (∼37 ms). These excellent properties allow this humidity sensor to noninvasively monitor the RRs of not only humans but also rats that have a much faster RR and much smaller tidal volume than humans. Moreover, this sensor could also be efficiently used for the real-time monitoring of the recovery process of rats from anesthesia.