YSZ-based acetone sensor using a Cd_2SnO_4 sensing electrode for exhaled breath detection in medical diagnosis

摘要

Breath analysis using simple gas sensors is becoming one of the important methods for non-invasive, painless and early diagnosis of certain diseases. Among them, the acetone sensor plays a crucial role in screening and diagnosis of diabetes by detecting acetone concentration in exhaled breath. Here, a stabilized zirconia (YSZ)-based mixed potential type acetone sensor combining with Cd_2SnO_4 sensing electrode (SE) is introduced, which is expected to be used for pre-diagnosis of diabetes. The developed sensor can effectively detect acetone in the concentration range of 0.05-200 ppm at an optimal operating temperature of 600 °C, with sentivities of -17.3 mV/ppm to 0.05-2 ppm acetone and -88.6 mV/decade to 5-200 ppm acetone. Both the sensing behavior and electrochemical test confirm that the sensing principle of the sensor follows to the mixed potential mechanism. The excellent repeatability, selectivity and long-term stability of the sensor make it reliable in the actual application. In addition, clinical tests for the sensor toward exhaled breath of healthy people and diabetic patients are proposed and strong correlations have been established among the response values, acetone concentrations and blood ketone concentrations, which fully demonstrates the great potential of the sensor for pre-diagnosis of diabetes.