Determination of 2-methylisoborneol and geosmin in water by gas chromatography-mass spectrometry using stir bar sorptive extraction

Abstract

A method is described for the determination of 2-MIB and geosmin by gas chromatography-mass spectrometry (GC-MS) using stir bar sorptive extraction (SBSE). The detection limits using selected ion monitoring (SIM) were compared between solid phase microextraction (SPME) and stir bar sorptive extraction (SBSE). Since polydimethylsiloxane (PDMS) is only available for stationary phase on the stir bar for SBSE, a 100-μm PDMS fiber was used for SPME due to the same sorption mechanism. The sensitivities of the SBSE method was 54 times higher for 2-MIB and 10 times higher for geosmin than those of the SPME method. The detection limits of the SBSE method evaluated in river water were 0.33 and 0.15 ng/L respectively for 2-MIB and geosmin. The reproducibilities (n = 5) were 9.2 and 3.7%, respectively, at 2 ng/L for 2-MIB and geosmin.