Comparison of stir bar sorptive extraction and solid-phase microextraction to determine halophenols and haloanisoles by gas chromatography-ion trap tandem mass spectrometry.

Solid-phase microextraction by immersion (IS-SPME) and headspace mode (HS-SPME), together with stir bar sorptive extraction (SBSE), have been assayed in combination with gas chromatography-ion trap tandem mass spectrometry (MS/MS) for analysing 2,4,6-trichlorophenol, 2,3,4,6-tetrachlorophenol, 2,4,6-tribromophenol, 2,4,6-trichloroanisole, 2,3,4,6-tetrachloroanisole and 2,4,6-tribromoanisole in different liquid matrices. Once, the optimization of MS/MS fragmentation analysis was carried out, sample enrichment was performed using the three mentioned extraction methods, and comparison through the determination of linearity, and LOD and LOQs were carried out. SBSE and IS-SPME methods described enabled us to determine the target compounds at ng/l levels, concentrations lower than their olfactory threshold, which is not the case of HS-SPME. SBSE showed a higher concentration capability than both SPME techniques, especially when compared to the HS-SPME mode. Thus, SBSE should be the definitive technique to analyse halophenols and haloanisoles in aqueous matrices. SBSE has been also applied to nine aqueous matrices as different as tap water, wines or commercial lemon juice extract.