Microwave-assisted extraction, membrane-assisted solvent extraction combined with gas chromatography/electron-capture detection applied to the analysis of polychlorinated biphenyls in bivalve molluscs

Abstract

Microwave-assisted extraction as an initial extraction step and membrane-assisted solvent extraction (MASE) as a clean up–extraction–concentration step were applied to the determination of polychlorinated biphenyls (PCBs) in mussel samples. The MASE conditions, methanol percentage in aqueous extract of sample, extraction time, extraction temperature, shaking speed, and extractant solvent volume, were optimised using a Plackett–Burman factorial design. The purified extract was analysed using gas chromatography/electron-capture detector. The results show that extraction time was statistically significant for PCBs 31, 28, 118 and 180 and shaking speed for PCBs 153, 138 and 156, both factors had positive estimated effects. The other investigated factors were not statistically significant. The extraction efficiency of the whole method was between 74% and 100% and the relative standard deviation ranged from 2% to 15%. The detection limits were about 0.1–0.9 µg kg⁻¹.

Keywords:

• microwave-assisted extraction
• membrane-assisted solvent extraction
• polychlorinated biphenyls
• Plackett–Burman factorial design
• gas chromatography–electron-capture detector
• bivalve mollusc