Automated sequential solid-phase microextraction to address displacement effects in the quantitative analysis of polar compounds

•High-throughput SPME-GC-MS method was developed for polar compounds accurate determinations.•The sequential SPME approach avoids displacement effects.•Matrix-compatible coating material was used for decreasing the matrix effect.•The method showed good quantitative results with high sensitivity and precision. Solid-phase microextraction (SPME) is a simple and effective sample-preparation technique for the analysis of real-world samples. However, there is a phenomenon that a swelling or saturation of available sorption sites on the solid SPME coating can be caused by compounds with high affinities towards the solid coating present in matrices with low level binding matrix, thus resulting in the displacement of lower-affinity compounds. This phenomenon, known as the displacement effect, can make the quantitative analysis of polar analytes rather challenging. This work attempts to mitigate the impact of displacement effects by combining sequential SPME with an autosampler system. To apply the appropriate thin-film (TF) SPME membranes in the autosampler system, two special TF-SPME holders are designed to enable sampling in headspace (HS) or direct immersion (DI) mode. Next, two automated sequential SPME strategies are proposed to minimize the impact of displacement: the application of a PDMS-coated thin film in HS or DI mode (keeping the thin film in the vial without pausing the automated sequential SPME after the first round of extraction), and the use of a DVB/CAR/PDMS-coated fiber in DI mode. The results indicate that the proposed sequential SPME strategy enables the extraction of greater amounts of polar compounds, as the use of the PDMS-coated thin film in step 1 reduces the concentration of nonpolar compounds in the sample, and thus, the displacement of polar compounds on the sorbent. Finally, the proposed automated sequential method is applied to address displacement effects in the quantification of polar compounds in environmental analysis. The results of these assays clearly demonstrate that the proposed sequential SPME method not only effectively minimizes displacement effects, but it also successfully achieves full automation through its use of an autosampler system.