Abstract
Environmental samples include a wide variety of complex matrices, with low concentrations of analytes and presence of several interferences. Sample preparation is a critical step and the main source of uncertainties in the analysis of environmental samples, and it is usually laborious, high cost, time consuming, and polluting. In this context, there is increasing interest in developing faster, cost-effective, and environmentally friendly sample preparation techniques. Recently, new methods have been developed and optimized in order to miniaturize extraction steps, to reduce solvent consumption or become solventless, and to automate systems. This review attempts to present an overview of the fundamentals, procedure, and application of the most recently developed sample preparation techniques for the extraction, cleanup, and concentration of organic pollutants from environmental samples. These techniques include: solid phase microextraction, on-line solid phase extraction, microextraction by packed sorbent, dispersive liquid-liquid microextraction, and QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe).
ACKNOWLEDGMENTS
The work has been supported by Fundação para a Ciência e Tecnologia – FCT (PhD grants to Ana Rita Ribeiro and Alexandra S. Maia respectively, SFRH/BD/64999/2009 and SFRH/BD/86939/2012, from QREN-POPH, European Social Fund and MCTES). The authors also wish to acknowledge the support from CESPU (03-GCQF-CICS-11), FCT (FLUOROPHARMA, PTDC/EBB-EBI/111699/2009), CEQUIMED-PEst-OE/SAU/UI4040/2011.