We studied high-performance ion-selective field-effect transistors (ISFETs) to detect human salivary stress-marker candidates using direct potentiometry. For acute stress monitoring, we investigated various kinds of sensor materials, designed nitrate-sensing materials, designed plasticizers and biocompatible polymers for salivary nitrate ISFETs. We prepared prototype of silicon based FET nitrate checker using specially ordered FET mV checker. The prototype of nitrate ISFETs showed almost the theoretical Nernst response with a response time of less than 10 seconds. As we applied whole human saliva using direct potentiometry, we obtained excellent relationship with conventional ionchromatography. We successfully demonstrated several acute stress tasks for healthy volunteers using wearable heart rate monitor and prototype of salivary nitrate checkers based on NO₃ -ISFETs. We also discussed high-performance organic transistor based FET (OFET) biosensors for stress monitoring using extended-gate type configuration towards stress monitoring.

Date Published: 10 May 2019
PDF: 6 pages
Proc. SPIE 11007, Advanced Environmental, Chemical, and Biological Sensing Technologies XV, 1100702 (10 May 2019); doi: 10.1117/12.2518851

Published in SPIE Proceedings Vol. 11007:
Advanced Environmental, Chemical, and Biological Sensing Technologies XV
Tuan Vo-Dinh, Editor(s)