Porous layer open tubular nano liquid chromatography directly coupled to electron ionization mass spectrometry

A 25 mu m i.d x 1.2 m length PS-DVB porous layer open tubular column (PLOT) was prepared and assessed in the configuration of a nano liquid chromatography coupled to an electron ionization mass spectrometry system (OT-nanoLC-EI-Ms), via the direct insertion of the column outlet into the ionization source. The developed system's operational parameters were comprehensively studied, and the setup performance was investigated employing both unidimensional and column switching configurations. As a result, the OT-nanoLC-EI-MS system demonstrated competitive applicability in separating non-amenable ESI compounds, such as polyaromatic hydrocarbons (PAHs) and non-amenable GC compounds such as thermolabile pesticides. Furthermore, with excellent chromatographic performance, the PLOT columns can work under more compatible EI-detection conditions - such as the elution with 100% organic solvent. For example, PAHs retention factors ranged between 1.5 and 2.2 for 100% MeCN mobile phase, and more than 33,0 0 0 plates per meter for naphthalene at 50 nL/min flow rate. In analyzing thermolabile pesticides, the column switching PLOT-nanoLC-EI-MS system provided LODs of 25 mu g/L, demonstrating suitable intra e interday reproducibility (% RSD < 13%, n = 3), and possibilities the direct injection of raw samples with suitable robustness.(c) 2022 Elsevier B.V. All rights reserved.

Automated summary

A 25 μm i.d x 1.2 m length PS-DVB porous layer open tubular column (PLOT) was prepared and assessed in the configuration of a nano liquid chromatography coupled to an electron ionization mass spectrometry system (OT-nanoLC-EI-Ms). The system demonstrated competitive applicability in separating non-amenable ESI compounds, such as polyaromatic hydrocarbons (PAHs) and non-amenable GC compounds such as thermolabile pesticides. With excellent chromatographic performance, the PLOT columns can work under more compatible EI-detection conditions.