An Acetone Sensor Based on Plasma-Assisted Cataluminescence and Mechanism Studies by Online Ionizations

The new development of noninvasive diagnosis in breath analysis requires the fabrication of inexpensive and rapid sensing technologies, whose sensing mechanisms are further encouraged to be studied. Here based on the dramatically enhanced plasma-assisted cataluminescence (PA-CTL) signals, a new sensor was constructed for the detection of acetone, an important biomarker of diabetes mellitus in breath. As demonstrated, the PA-CTL-based sensor showed good sensitivity, repeatability, and selectivity in acetone detection, which also displayed good recovery and stability in exhaled breath. An online ionization system of low-temperature plasma mass spectrometry was designed to couple with the PA-CTL sensor for examining changes of molecules during the sensing. For the first time, some important ions were recorded in real time, which helped to clear the reaction mechanism of radical-based catalytic oxidation combined with the CTL data. By the fabrication and relative comprehensive understanding of the PA-CTL sensor for acetone detection, this work would promote the development of CTL sensing techniques and inspire a potential pathway for rapid and noninvasive diagnosis.