title: Chemiresistive Electronic Nose toward Detection of Biomarkers in Exhaled Breath.
abstract: Detection of gas-phase chemicals finds a wide variety of applications, including food and beverages, fragrances, environmental monitoring, chemical and biochemical processing, medical diagnostics, and transportation. One approach for these tasks is to use arrays of highly sensitive and selective sensors as an electronic nose. Here, we present a high performance chemiresistive electronic nose (CEN) based on an array of metal oxide thin films, metal-catalyzed thin films, and nanostructured thin films. The gas sensing properties of the CEN show enhanced sensitive detection of H2S, NH3, and NO in an 80% relative humidity (RH) atmosphere similar to the composition of exhaled breath. The detection limits of the sensor elements we fabricated are in the following ranges: 534 ppt to 2.87 ppb for H2S, 4.45 to 42.29 ppb for NH3, and 206 ppt to 2.06 ppb for NO. The enhanced sensitivity is attributed to the spillover effect by Au nanoparticles and the high porosity of villi-like nanostructures, providing a large surface-to-volume ratio. The remarkable selectivity based on the collection of sensor responses manifests itself in the principal component analysis (PCA). The excellent sensing performance indicates that the CEN can detect the biomarkers of H2S, NH3, and NO in exhaled breath and even distinguish them clearly in the PCA. Our results show high potential of the CEN as an inexpensive and noninvasive diagnostic tool for halitosis, kidney disorder, and asthma.
authors.affiliation: Center for Electronic Materials, Korea Institute of Science and Technology (KIST) , Seoul 136-791, Republic of Korea.|Department of Material Science and Engineering, Yonsei University , Seoul 120-749, Republic of Korea.
authors.forename: Hi Gyu
authors.initials: HG
authors.lastname: Moon
authors.affiliation: Department of Material Science and Engineering, Yonsei University , Seoul 120-749, Republic of Korea.|Department of Mechanical Engineering, Yonsei University , Seoul 120-749, Republic of Korea.
authors.forename: Youngmo
authors.initials: Y
authors.lastname: Jung
authors.affiliation: Center for Electronic Materials, Korea Institute of Science and Technology (KIST) , Seoul 136-791, Republic of Korea.|KU-KIST Graduate School of Converging Science and Technology, Korea University , Seoul 136-701, Republic of Korea.
authors.forename: Soo Deok
authors.initials: SD
authors.lastname: Han
authors.affiliation: Center for Electronic Materials, Korea Institute of Science and Technology (KIST) , Seoul 136-791, Republic of Korea.
authors.forename: Young-Seok
authors.initials: YS
authors.lastname: Shim
authors.affiliation: Sensor System Research Center, Korea Institute of Science and Technology (KIST) , Seoul 136-791, Republic of Korea.
authors.forename: Beomju
authors.initials: B
authors.lastname: Shin
authors.affiliation: Sensor System Research Center, Korea Institute of Science and Technology (KIST) , Seoul 136-791, Republic of Korea.
authors.forename: Taikjin
authors.initials: T
authors.lastname: Lee
authors.affiliation: Center for Electronic Materials, Korea Institute of Science and Technology (KIST) , Seoul 136-791, Republic of Korea.
authors.forename: Jin-Sang
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Sensor System Research Center, Korea Institute of Science and Technology (KIST) , Seoul 136-791, Republic of Korea.
authors.forename: Seok
authors.initials: S
authors.lastname: Lee
authors.affiliation: Department of Mechanical Engineering, Yonsei University , Seoul 120-749, Republic of Korea.
authors.forename: Seong Chan
authors.initials: SC
authors.lastname: Jun
authors.affiliation: Department of Material Science and Engineering, Yonsei University , Seoul 120-749, Republic of Korea.
authors.forename: Hyung-Ho
authors.initials: HH
authors.lastname: Park
authors.affiliation: Sensor System Research Center, Korea Institute of Science and Technology (KIST) , Seoul 136-791, Republic of Korea.
authors.forename: Chulki
authors.initials: C
authors.lastname: Kim
authors.affiliation: Center for Electronic Materials, Korea Institute of Science and Technology (KIST) , Seoul 136-791, Republic of Korea.|KU-KIST Graduate School of Converging Science and Technology, Korea University , Seoul 136-701, Republic of Korea.
authors.forename: Chong-Yun
authors.initials: CY
authors.lastname: Kang
mesh_terms: D015415:Biomarkers; D001944:Breath Tests; D062609:Electronic Nose; D049329:Nanostructures; D010087:Oxides
chemical_list: D015415:Biomarkers; D010087:Oxides
keywords: biomarkers; chemiresistive sensor; electronic nose; exhaled breath analyzer; nanostructural thin film metal oxides; noninvasive diagnostic tool; sensor array