| Abstract |
In this work, polyurethane-based (PU) devices having cylindrical geometry soaked with suitable organic solvents are proposed for microextraction analysis. This novel analytical approach (PU microextraction; PU mu E) operates under the floating sampling technology for extraction, followed by mechanical compression using a manual syringe for back-extraction. To test the performance of the PU mu E method, two series of priority contaminants were used as model compounds (group \#1: metalaxyl-M, penconazole and tebuconazole; group \#2: atrazine, terbuthylazine, alachlor and benzo[a]pyrene) and extracted from aqueous samples followed by gas chromatography-mass spectrometry (GC-MS) analysis. The preparation of the PURE devices and the device handling procedures are described. Also, the optimization experiments as well as the application of the new method to real matrices are discussed. Assays performed on 25 mL water samples spiked at trace levels yielded average recoveries ranging from (50.1 +/- 6.7) \% to (93.3 +/- 1.6) \%, under optimized experimental conditions. The analytical performance showed good detection limits (0.01-0.50 mu g/L) and linear dynamic ranges (0.1-50.0 mu g/L) with acceptable determination coefficients (r(2) > 0.9937). Excellent repeatability was also achieved in both intraday (RSD < 3.5\%) and inter-day (RSD < 7.0\%) experiments. With standard addition quantification, the proposed analytical approach revealed good sensitivity and selectivity at trace levels with absence of matrix effects for environmental water and wine samples. The PURE technique is simple, cost-effective and very easy to apply, using an all-in-one microextraction concept. (C) 2017 Elsevier B.V. All rights reserved. |
