Applications of a novel flame ionisation detector for liquid chromatography

Over the last twenty years liquid chromatography has come to dominate analytical chemistry because of its ability to analyse a wide range of products from pharmaceuticals to environmental and forensic samples but some groups of analytes still cause practical difficulties in detection. The most common detector for HPLC is the UV-Visible spectroscopic detector, which is both sensitive and linear. However, detection is limited to analytes containing chromophores. For other analytes the analyst has to either rely on derivatisation or employ a “universal detector”, such as the less sensitive refractive index detector or the evaporative light scattering detector, which cannot easily detect small, volatile compounds. The universal flame ionisation detector when interfaced to LC has had problems in the past because of the signal from the organic component of the mobile phase, however, the use of superheated water as the eluent overcomes this problem and enables reversed-phase separations with the ability to detect analytes with and without chromophores. A revised design of interface (patent pending) enables a wide range of columns to be employed with differing flow rates.