title: Optimisation and comparison of microwave-assisted extraction and Soxhlet extraction for the determination of polychlorinated biphenyls in soil samples using an experimental design approach.
abstract: Optimisation of microwave-assisted extraction (MAE) for the extraction of polychlorinated biphenyls (PCBs) from soil samples has been accomplished using an experimental design approach. Variables studied have been: percentage of acetone (v/v) in an acetone:n-hexane mixture, solvent volume, extraction time, microwave power and pressure inside the extraction vessel. Five samples of a certified soil (CRM 481) have been extracted under the optimum conditions of the developed method and the results have been compared to those obtained by Soxhlet extraction. Good recoveries (>95%) have been obtained for all the PCBs studied. All extracts have been analysed by gas chromatography/mass spectrometry (GC/MS) and an optimum determination method for the electron impact mass spectrometric (EIMS) has also been developed.
authors.affiliation: Kimika Analitikoaren Saila, Euskal Herriko Unibertsitatea, 644 P.K., E-48080 Bilbao, Spain.
authors.forename: O
authors.initials: O
authors.lastname: Zuloaga
authors.forename: N
authors.initials: N
authors.lastname: Etxebarria
authors.forename: L A
authors.initials: LA
authors.lastname: Fernández
authors.forename: J M
authors.initials: JM
authors.lastname: Madariaga