Deep eutectic solvent coated paper: Sustainable sorptive phase for sample preparation

Paper-based sorptive phases have gained attention recently due to the low-cost and sustainable charac-ter of the cellulosic substrate. However, the sustainability of the resulting phase can be limited by type of coating used for analytes isolation. In this article, this limitation is overcome by using deep eutectic solvents (DES) as coating. To this aim, a Thymol-Vanillin DES is synthesized and deposited on pre-cut cel-lulose paper strips. The paper-supported DES is employed as sorptive phase for the isolation of selected triazine herbicides for environmental waters analysis. The isolated analytes are finally determined by gas chromatography-mass spectrometry using selected ion monitoring. The method is optimized according to the critical variables that potentially affect its analytical performance such as sample volume, extractant amount, extraction time and sample ionic strength. The method was characterized in terms of sensitivity, accuracy and precision and its applicability was evaluated for the analysis of real environmental water samples. Good linearity values (R 2 > 0.995) were obtained for all the analytes. Limits of detection (LODs) ranged from 0.4 to 0.6 mu g L -1 and the precision, expressed as relative standard deviation (RSD) was bet-ter than 14.7%. The relative recoveries, calculated in spiked well and river samples, were in the range 90-106%. (c) 2023 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ )

Automated summary

Paper-based sorptive phases have been developed with deep eutectic solvents (DES) as coating for the isolation and analysis of selected triazine herbicides in environmental water samples. The method demonstrates good sensitivity, accuracy, and precision, with wide applicability.