No abstract

In this study, the quantitative determination of gaseous biogenic volatile organic compounds (BVOCs) including monoterpenes and sesquiterpenes was accomplished using a solid-phase extraction-type collection device. The collection device was fabricated by packing styrene-divinylbenzene polymer particles into a specially designed glass cartridge. The retention performance of the collection device for BVOCs was quantitatively evaluated at 35°C with different volumes of air samples. The device showed good retention performance for the investigated BVOCs, that is, no breakthrough occurred for monoterpenes up to an air sampling volume of 150 L or for sesquiterpenes up to a sampling volume of 30,000 L. The elution performance was evaluated by passing organic solvents into the collection device, and an excellent elution recovery was obtained with 10 mL dichloromethane. Finally, the analytical method using the collection device was applied to determine the gaseous monoterpenes and sesquiterpenes from a grated carrot and the air inside a wooden house, and the results demonstrated the applicability of the method for the quantitative determination of BVOCs in several sample matrices.

This manuscript describes the determination of ammonia (NH3) in aqueous samples by purge-and-trap extraction using a needle-type extraction device with gas chromatography-barrier discharge ionization detector (GC-BID). NH3 was purged from the aqueous samples in basic conditions and then salted out with sodium chloride. Purged ammonia was trapped onto non-volatile carboxylic acid-coated macroporous terephthalic acid particles, which were contained within the needletype extraction device. The analyte (NH3) was thermally desorbed by heating the extraction needle in the GC injection port, and detected by BID. After the optimization of both purge and extraction conditions, the linearity and sensitivity of the proposed method were evaluated. The limit of detection was found to be 2.0 mg L-1 at a headspace sampling volume of 100 mL. The method applicability was confirmed by the determination of spiked NH3 in tap water and river water samples.