Nanosensor and Breath Analyzer for Ammonia Detection in Exhaled Human Breath

Dept. of Mater. Sci. & Eng., Stony Brook Univ., Stony Brook, NY, USA
IEEE Sensors Journal (Impact Factor: 1.76). 02/2010; 10(1):49 - 53. DOI: 10.1109/JSEN.2009.2036050
Source: IEEE Xplore


The detection and monitoring of gases in exhaled human breath up to date has been limited by the lack of appropriate materials and technologies which could rapidly and selectively identify the presence and monitor the concentration of trace levels of specific analytes-biomarkers. We present a metal oxide-based nanosensor that is highly specific to ammonia gas in breath-simulating environments at low part-per-billion concentrations. The design of a handheld breath analyzer for gas detection in exhaled human breath is described. Semiconducting ceramics are presented as suitable sensor materials for easy and affordable noninvasive diagnostics.

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    • "Sensor selectivity is defined here as higher sensitivity to a given gas or class of gases in the presence of interfering gaseous species. The authors have demonstrated in their earlier research [7] [8] [9] [10] [11] that it is possible to control the microstructure of nanocrystalline metal oxide films and the operating temperature of the sensor so as to employ oxide polymorph phases that are sensitive to only a specific class of gaseous analytes or even be specific to a single species. The concept has been extended in this paper to the detection of multiple biomarkers by sensor arrays through temperature control of a simple metal oxide thin film-based gas-sensing element. "
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    • "These gasoxide interaction based mechanisms provide the basis for further investigations to develop new analyte-biomarkers for exhaled breath. The importance of this information (sensing mechanisms) have been emphasized and reviewed recently by Gouma et al. [17] [18] [19] [20] with respect to crystal structures and surface grain boundaries. In contrast , our proposal deals with the surface and gaseous chemical compositions, and the difference of the electric dipole moment as the origin of interaction between a given oxide and a gas molecule, atom or plasma. "
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