Determination of the alkyl- and methoxy-phenolic content in wood extractives by micellar solid-phase microextraction and gas chromatography–mass spectrometry

This work combines the utilization of the micellar media during the extraction step and the focused microwave-assisted extraction followed by the solid-phase microextraction–gas chromatography/mass spectrometry (SPME–GC/MS) to determine the alkyl- and methoxy-phenolic content in wood extractives. The proposed environmental-friendly method is mainly characterized by short analysis times (5 min for the microwaves extraction step) and for avoiding the use of organic solvents. Different surfactants were tried for the extraction process: the cationic surfactant CTAB and the non-ionic surfactants Triton X-100 and POLE, with similar extraction efficiencies (85.5–99.7%). The overall method presents limits of detection in the ng g−1 region for the alkylphenols (from 7 to 150 ng g−1) and in the μg g−1 region for the methoxyphenols (from 0.80 to 22.9 μg g−1). The vanillin was the compound most abundant in the wood extractives studied, with concentrations up to 116.2 mg kg−1.