Amperometric Sensing of Ethylene Oxide in the Gas Phase

• Published in: Analytical chemistry (Washington) Vol. 72; no. 10; pp. 2206 - 2210
• Main Authors: Hodgson, Alexia W. E, Jacquinot, Patrick, Hauser, Peter C
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 15.05.2000
• Subjects: Analytical chemistry; Carcinogens - analysis; Chemistry; Ethylene Oxide - analysis; Exact sciences and technology; Gases; General, instrumentation; Oxygen; Water; Performance evaluation; Membrane electrode; Porous electrode; Three membered ring; Polymer solid electrolyte; Volatile organic compound; Chemical sensor; Oxygen heterocycle; Electrochemical characteristic; Electrochemical detector; Ion exchange membrane; Ethylene oxide; Gas detector; Electrode potential
• ISSN: 0003-2700; 1520-6882
• DOI: 10.1021/ac991247l

The sensing device used is based on a porous Pt electrode, which is supported on an ion-exchange membrane and directly exposed to the gas phase. Under acid conditions, ethylene oxide was found to be oxidized on the platinum oxide surface at +550 mV vs MSE, thus enabling its monitoring via the measurement of the associated current. A detection limit of 15 ppb was obtained, based on a signal-to-noise ratio of three, and a linear dynamic range was found up to 100 ppm. The effects of mass transport, humidity, and oxygen on the cell response, as well as the cross sensitivity to other organic vapors and inorganic gases are discussed.