Micro-Flame Photometric Detection in Miniature Gas Chromatography on a Titanium Tile

A novel miniaturized gas chromatography–flame photometric detection device built within a titanium platform (Ti µGC–FPD) is presented. The 7.5 cm × 15 cm monolithic Ti device contains both an OV-101 coated separation column (5 m × 100 µm i.d.) and a shielded cavity to house the hydrogen-rich detector flame. The FPD employs a micro counter-current flame (about 250 µm in diameter) that is stabilized by opposing relatively low flows of oxygen and hydrogen (7–10 mL/min O 2 and 40 mL/min H 2 ). Under optimal conditions, the minimum detectable limits are about 70 pg S/s for sulfur and 8 pg P/s for phosphorous. The natural (i.e., unfiltered) selectivity for these responses over carbon is near 10 4.3 for S/C and 10 5 for P/C. Even greater selectivity over hydrocarbons can further still be obtained by employing conventional interference filters. Overall, good separations with stable and sensitive detector performance are obtained with the device, and its sturdy Ti structure supports robust operation. Results indicate that this Ti µGC–FPD device may be a useful alternative approach for incorporating selective FPD sensing in µGC analyses. Graphical Abstract