Highly sensitive carbon nanotubes-SnO2 nanocomposite sensor for acetone detection in diabetes mellitus breath

Multiwall carbon nanotubes (MWCNTs)/SnO2 nanocomposites were synthesized by ultrasonic-assisted deposition-precipitation method and used for detection of acetone in the same range of concentrations as in diabetes mellitus breath. The nanocomposite samples were characterized by BET, FE-SEM, XRD and TEM. MWCNTs with an average size of about 60 nm are coated with and uniformly dispersed in 5-10 nm SnO2 nanoparticles matrix. To diagnose diabetes, the sensors responses to ppm concentrations of acetone were measured in a flow system at various temperatures and 85% relative humidity. Addition of MWCNTs dramatically enhances the sensors response to acetone. Moreover, the sensors response to ethanol, as an interfering species with acetone in human breath, was also measured. Breath humidity increases the conductivity of the sensing materials and therefore, lowers the sensors response to acetone. (C) 2014 Elsevier B.V. All rights reserved.