title: Fractional exhaled nitric oxide measurement with a handheld device.
abstract: A sensing system for fractional exhaled nitric oxide (FeNO) measurement is presented, which is characterized by a compact setup and a cost potential to be made available for the patient at home. The sensing is based on the work function measurement of a phthalocyanine-type sensing material, which is shown to be sufficiently sensitive for NO(2) in the ppb range. The transducer used to measure the work function is a field effect transistor with a suspended gate electrode. Selectivity is given with respect to other breath components including typically metabolic by-products. The measurement system includes breath treatments in a simple setup, which essentially are dehumidification and a quantitative conversion of NO to NO(2) with a conversion rate of approx. 95%, using a disposable oxidation catalyst. The accomplishment of the correct exhalation maneuver and feeding of the suited portion of exhaled air to the sensor is provided by breath sampling means. The sensor is not gas consuming. This allows us to fill the measurement chamber once, instead of establishing a gas flow for the measurement. This feature simplifies the device architecture. In this paper, we report on sensor characteristics, system architecture and measurement with artificial breath-gas as well as with human breath with the device.
authors.affiliation: Siemens AG, Corporate Technology, Otto-Hahn-Ring 6, 81739 Munich, Germany. erhard.magori@siemens.com
authors.forename: Erhard
authors.initials: E
authors.lastname: Magori
authors.forename: Karsten
authors.initials: K
authors.lastname: Hiltawsky
authors.forename: Maximilian
authors.initials: M
authors.lastname: Fleischer
authors.forename: Elfriede
authors.initials: E
authors.lastname: Simon
authors.forename: Roland
authors.initials: R
authors.lastname: Pohle
authors.forename: Oliver
authors.initials: O
authors.lastname: von Sicard
authors.forename: Angelika
authors.initials: A
authors.lastname: Tawil
mesh_terms: D001249:Asthma / Q000175:diagnosis / Q000378:metabolism*; D001944:Breath Tests / Q000295:instrumentation*; D004867:Equipment Design; D045853:Exhalation; D006801:Humans; D009569:Nitric Oxide / Q000032:analysis*; D015203:Reproducibility of Results
chemical_list: D009569:Nitric Oxide