Micro-Flame Ionization Detection Using a Catalytic Micro-combuster

A microflame-based detector has been developed for sensing a broad range of chemical analytes. This detector combines calorimetry and flame ionization detection (FID) to produce unique analyte signatures. The microcombustor consists of a micromachined microhotplate with a catalyst on its surface, such as platinum/alumina, to rapidly initiate the ionization event. The low power microcombustor design permits quick, efficient heating of the deposited film. To perform calorimetric detection of analytes, the change in power required to maintain the resistive microhotplate heater at a constant temperature is measured. For FID, electrodes are placed around the microcombustor flame zone with an electrometer circuit measuring the production of ions. The calorimetric and FID modes respond generally to all hydrocarbons. Importantly these detection modes can be established on one convenient simultaneous microcombustor platform. The performance of the microFID mode is emphasized herein