A simple and fast micromethod for the analysis of polychlorinated biphenyls in air by sorbent enrichment and ultrasound-assisted solvent extraction

Abstract

A combination of sorbent enrichment and ultrasound-assisted solvent extraction has been used to determine polychlorinated biphenyls in air. Analytes were sampled by pumping a known volume of air through a porous polymer (Tenax TA). The enriched adsorbent was transferred into a glass vial, and ultrasound-assisted extraction of the analytes was then performed in n-hexane. Quantification was carried out by using gas chromatography coupled to tandem mass spectrometry. Breakthrough volume of the sampling step was studied, indicating that 10 m−3 of air could be processed without losses of the most volatile compounds. Good recoveries (75–86%) were obtained, and limits of detection at the sub ng m−3 were achieved for all the analytes. The proposed method is very simple and fast, voiding the use of large solvent volumes and time-consuming preconcentration steps.