Flameless operating mode for improved multiple flame photometric detection in gas chromatography

Date
2024-04-25
Journal Title
Journal ISSN
Volume Title
Publisher
Springer Nature
Abstract
A novel fameless operating mode is introduced, which improves the response of a multiple fame photometric detector (mFPD). The mFPD normally has analyte travel through 4 ‘worker’ fames in series before entering a fnal ‘analytical’ fame where its emission is monitored. Here, it is found that when the analytical fame is not ignited, background luminescence is reduced over 30 times and the strong analyte chemiluminescence of the worker fames can be made to extend a large distance (~10 fame widths) into the analytical fame region where it is detected. This occurs for phosphorous (HPO*), quadratic sulfur (S2*), and linear sulfur (HSO*) emission. Conversely, carbon emission resides inside the worker fames and yields a small negative signal. As a result, very good selectivity over carbon is observed, and improved minimum detectable limits (MDL) of 4 pg S/s (S2*) and 0.3 pg P/s (HPO*) are obtained, which are up to 20 times lower than previous values reported for the mFPD. Further, linear sulfur (HSO*) yields an MDL of 6 pg S/s, which is over 3 times lower than values reported for other FPDs. Due to the worker fames present in this mode, other benefts of regular mFPD operation are maintained, like uniform analyte response and large quenching resistance. In application, a trace benzothiophene analyte is readily detected within a concentrated diesel fuel matrix in the fameless mFPD mode, while no response is observed in the conventional FPD mode. Results indicate that this fameless operating mode is advantageous for sulfur and phosphorous analysis.
Description
The version of record of this article, first published in Chromatographia is available online at Publisher’s website: https://doi.org/10.1007/s10337-024-04335-x
Keywords
sulfur analytes, flame photometric detection, quenching, gas chromatography, multiple flame photometric detector (mFPD)
Citation
Nguyen, B., & Thurbide, K. B. (2024). Flameless operating mode for improved multiple flame photometric detection in gas chromatography. Chromatographia. https://doi.org/10.1007/s10337-024-04335-x