Gas chromatography analysis of benzene, toluene, ethylbenzene and xylenes using newly designed needle trap device in aqueous samples

A newly designed needle trap device with Carbopack X as a sorbent material is used for sampling, preconcentration and injection of volatile analytes benzene, toluene, ethylbenzene and xylenes (BTEX) into gas chromatograph. The closed system of stripping the analytes from water samples was used. An injection port with a modified metal liner was used to desorb analytes trapped in needle trap device. The main advantage of needle trap device consists in the simple methodology and easiness and rapidity of the analysis. Needle trap device is suitable for sampling in field. The experimental parameters as breakthrough volume of stripping gas, linearity, repeatability and limit of detection (LOD) and quantification (LOQ) were investigated. LOD ranges from 0.05 to 0.07 μg L−1 and relative standard deviation ranges from 0.5% to 11.6% at concentrations 5 and 0.1 μg L−1, respectively.