Functionalized graphene-based chemiresistive electronic nose for discrimination of disease-related volatile organic compounds

Abstract

This paper reports a procedure of building a functionalized reduced graphene oxide (rGO) library and an electronic nose based on the library. Functionalized rGO was prepared by reducing and modifying graphene oxide (GO) with chemically diverse amine ligands. We used the unmodified rGO and eight different functionalized rGO to build the chemiresistive sensor arrays in the electronic nose. Four potential cancer-related biomarkers in breath, ethanol, 2-ethylhexanol, nonanal and ethylbenzene, were used as the model volatile organic compounds (VOCs) analytes. The electronic nose showed linear responses to the model VOCs with high sensitivity of 25 ppm. Principal component analysis (PCA) results demonstrated the successful discrimination of the four model VOCs and binary VOC mixtures. The procedure of building the rGO library was simple and yielded consistent performance. We expected more versatile and sensitive electronic noses to be constructed based on the functionalized rGO library with potential applications in recognition and quantitative measurement of VOCs for health monitoring and disease diagnosis.