Multicomponent analysis of volatile organic compositions in vapor samples

Amounts of volatile organic compositions can be evaluated from vapor samples based on the time dependent response of a fuel cell contacted with the vapor sample at its anode. The time response of the fuel cell signal, e.g., voltage or current, is de-convoluted using a set of standard curves for an equivalent fuel cell configuration obtained separately for each of the volatile organic compositions of a fuel cell with an equivalent construction as the sample-evaluation fuel cell. The methodology can be implemented on a system with an appropriate vapor collection device suitable for the particular application. The method and system can be used to analyze breath samples to evaluate ethanol levels or other volatile organic composition. The system can be a breathalyzer, a vehicle interlock, a medical analysis device or a sensor of environmental or industrial interest.