Selective electrochemical detector for nitric oxide and method

US5580433A · kind A · utility

Inventors

• Charles K. Baker · San Antonio, US
• Mohan Ram · Banashankari, IN
• Stephen T. Wellinghoff · San Antonio, US

Key dates

• Filing date: Oct 11, 1995
• Grant date: Dec 3, 1996
• Expiry date: Oct 11, 2015

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N27/4074
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A thin film solid state amperometric detector for nitric oxide is provided based upon a mobile cation electrolyte that selectively transmits nitrosonium cations (NO*) therethrough. The presently most preferred embodiment employs NO-.beta.-alumina as the mobile cation electrolyte. The electrodes of the detector are preferably arranged in a bipotentiostat arrangement. The first and second working electrodes share a common reference electrode and a common counter electrode, which are positioned such that the potentials of the first and second working electrodes can be independently controlled. The first working electrode is exposed to a fluid (liquid or gaseous), whereas the second working electrode is normally isolated from the fluid. The first working electrode is set at a potential capable of oxidizing NO to NO+, the NO+ moves through the mobile cation solid electrolyte to the second electrode, and the second working electrode is set at a potential capable of reducing the NO+ back to NO. The detector has a diffusion barrier for the nitric oxide so that the voltage-current characteristics of the detector under diffusion limiting conditions are proportional to the concentration of ni…