Application of MXene as a new generation of highly conductive coating materials for electromembrane-surrounded solid-phase microextraction

Abstract For the first time, highly conductive thickly layered two-dimensional titanium carbide (MXene) was applied as a new coating agent for electromembrane-surrounded solid-phase microextraction (SPME) of triadimenol and iprodione as two model analytes. Preparation of the desired coated electrode was carried out using electrophoretic deposition of MXene on the surface of platinum electrode. Characterization of the prepared coated electrode was conducted using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The coated electrode was located inside a hollow fiber membrane impregnated by 2-nitrophenyl octyl ether as the supported liquid membrane (SLM), while an aqueous solution was injected inside the hollow fiber lumen. Separation and quantification of the analytes were carried out using a gas chromatography instrument equipped with mass spectrometric detection. The effective parameters of the microextraction procedure comprising pHs of sample solution and the acceptor phase, composition of the SLM, extraction time, and the applied voltage were optimized using one-variable at-a-time method. Under the optimal conditions, the calibration curves of the analytes were linear ( R 2 > 0.9973) in the range of 0.3–250.0 and 0.5–250.0 ng mL −1 for triadimenol and iprodione, respectively. The limit of detections was determined to be 0.10 and 0.15 ng mL −1 for triadimenol and iprodione, respectively. Repeatability and reproducibility of the method were evaluated by the calculation of intra-day and inter-day relative standard deviations (%). The applicability of the method was evaluated by quantitative analysis of the model analytes in environmental water samples. Relative recoveries in the range of 87.31–102.7% confirmed that the prepared coated electrode can be considered a reliable option in electromembrane-surrounded SPME techniques.