Carbonized MXene-polyvinylpyrrolidone as an adsorbent for solid-phase microextraction of polycyclic aromatic hydrocarbons from tea beverages prior to GC analysis

MXene-polyvinylpyrrolidone (MXene-PVP) was first prepared by physically doping combined with spray drying, which can overcome the aggregation of the MXene. Then, the MXene-PVP was carbonized to result in a carbonized MXene-PVP (MXene-PVP-C), which was then immobilized on stainless steel wire by sol–gel approach to prepare a new solid-phase microextraction (SPME) fiber. The prepared MXene-PVP-C coated fiber was studied for the extraction of 10 polycyclic aromatic hydrocarbons (PAHs) from tea beverages by using SPME method prior to gas chromatographic detection. The main SPME parameters, including extraction temperature, extraction time, salt concentration, sample solution pH and stirring rate, were investigated by central composite design methodology. Under the optimized conditions, the developed method gave the limits of detection of 0.03–0.15 µg/L, and the limits of quantification of 0.10–0.50 µg/L for the PAHs. The method recoveries for the PAHs in spiked tea beverages ranged from 78.6 % to 122 %. The single-fiber and fiber-to-fiber relative standard deviations were lower than 8.2 % and 9.6 %, respectively.