Abstract Title: | Comparing HPLC-MS and SFC-MS for PFAS analysis – an ionization efficiency-based effect study |
Presenter Name: | Ms Ardiana Kajtazi |
Company/Organisation: | Separation Science Group, Department of Organic and Macromolecular Chemistry, Ghent University, Ghent, Belgium |
Country: | Belgium |
Abstract Information :
Per- and poly-fluoroalkyl substances (PFAS) are classified as Persistent Organic Pollutants (POPs) due to the presence of highly stable C-F bonds. Given the significant environmental concerns associated with these contaminants, there is a need to enhance the quantitative and qualitative analysis of PFAS to better understand the extent of fluoroalkyl compound contamination. High-Performance Liquid Chromatography Mass Spectrometry (HPLC-MS) has been the most used technique for PFAS analysis and generally is the preferred method due to its superior selectivity, sensitivity and robustness. On the other hand, the significantly faster but under-used technique, Supercritical Fluid Chromatography Mass Spectrometry (SFC-MS), may prove also particularly useful for the enhanced separation of isomeric PFAS compound classes. Alternatively, the low-pressure drop in SFC allows for coupled column approaches operated at higher optimal velocities leading to more efficient chromatography within competitive analysis times. Currently, little information is available with respect to the performance of SFC-MS versus LC-MS under truly comparable conditions. Therefore, a fixed-restrictor approach is developed allowing a more facile comparison between the SFC and the HPLC-based ESI-MS detection. The approach also allows systematic investigation of the potential of ionization enhancing additives added post-column or to the mobile phase in LC and SFC. This includes the addition of e.g., m-nitrobenzyl alcohol (m-NBA), sulfolane, alcohols, pH modifiers and other adduct-forming agents. The performance of both approaches and of the influence of various known and novel ionization enhance agents will be demonstrated for a number of representative PFAS. Finally, both methods will also be compared in terms of sustainability and application.