20 - Flexible and stretchable indium-fallium-zinc oxide-based electronic devices for sweat pH sensor application

Abstract

Recent advancement in medical science with the capability to continuously monitor the key health parameters such as blood pressure, skin temperature, heart rate, diabetes, hydration/dehydration etc. using biological body specimen such as sweat, blood, urine, hair, saliva and so on have attracted significant interest. For example, the sweat generated by two sweat glands of human skin consist of 99% of water and 1% of electrolyte element that carry most important information about the health condition. In addition, sweat is readily available body fluid and the continuous monitoring of pH level of sweat through non-invasive technique avoids any undesirable risk of infection that are associated with the conventional invasive blood tests. In this regard, flexible and wearable field effect transistors are utilised to monitor the chemical component of the sweat through chemically active, sensitive, and reactive layers. This chapter discuss the recent progress in metal oxide based flexible and stretchable electronic devices and their sweat pH sensor-based health monitoring application.