An improved multiple flame photometric detector for gas chromatography

• A versatile and improved multiple flame photometric detector is introduced.
• Novel design is based upon fluidic channels within a planar stainless steel surface.
• Sulfur response spans over 4 orders of magnitude with MDL of 9 × 10−12 gS/s.
• Device provides exceptionally large resistance to hydrocarbon response quenching.
• New multiple flame emission mode can offer 10 to 20-fold improvement in S/N values.

An improved multiple flame photometric detector (mFPD) is introduced, based upon interconnecting fluidic channels within a planar stainless steel (SS) plate. Relative to the previous quartz tube mFPD prototype, the SS mFPD provides a 50% reduction in background emission levels, an orthogonal analytical flame, and easier more sensitive operation. As a result, sulfur response in the SS mFPD spans 4 orders of magnitude, yields a minimum detectable limit near 9 × 10−12 gS/s, and has a selectivity approaching 104 over carbon. The device also exhibits exceptionally large resistance to hydrocarbon response quenching. Additionally, the SS mFPD uniquely allows analyte emission monitoring in the multiple worker flames for the first time. The findings suggest that this mode can potentially further improve upon the analytical flame response of sulfur (both linear HSO, and quadratic S2) and also phosphorus. Of note, the latter is nearly 20-fold stronger in S/N in the collective worker flames response and provides 6 orders of linearity with a detection limit of about 2.0 × 10−13 gP/s. Overall, the results indicate that this new SS design notably improves the analytical performance of the mFPD and can provide a versatile and beneficial monitoring tool for gas chromatography.