Use of a temperature-responsive polymer micelle in microextraction method combined with gas chromatography-mass spectrometry for the determination of seven polycyclic aromatic hydrocarbons

Abstract

In this study, a novel microextraction method based on temperature-responsive polymer micelle has been designed combined with gas chromatography-mass spectrometry for the determination of seven polycyclic aromatic hydrocarbons (PAHs) in tea infusions. The method is based on the formation of micelles by poly (N-isopropylacrylamide)-block-poly (benzyl methacrylate) (PNIPAM-b-PBnMA) in aqueous samples at low temperatures and encapsulation of the targets due to the π–π and hydrophobic interaction between PBnMA with PAHs compounds, followed by the formation and insolubilization of agglomerates containing the preconcentrated analytes by increasing the temperature. Under the optimal conditions, good linearity was observed in the range of 0.1–100 μg L−1 with the coefficient of determination being above 0.9959. The limits of detection and limits of quantitation were in the range of 0.021–0.042 μg L−1 and 0.064–0.128 μg L−1, respectively. The intra-day and inter-day precision were 3.4–9.1% and 5.9–13.7%, respectively. The established method was applied successfully to analyze two tea infusions.