Field measurements of biogenic volatile organic compounds in the atmosphere using solid-phase microextraction Arrow

Abstract

Abstract. Biogenic volatile organic compounds (BVOCs) emitted by terrestrial vegetation participate in a diversity of natural processes. These compounds impact both on short-range processes, such as on plant protection and communication, and on high-range processes, by e.g. participation on aerosol particle formation and growth. The biodiversity of plant species around the Earth, the vast assortment of emitted BVOCs, and their trace atmospheric concentrations contribute to the high remaining uncertainties about the effects of these compounds on atmospheric chemistry and physics, and call for the development of novel collection devices that can offer portability with improved selectivity and capacity. In this study, a novel solid-phase microextraction (SPME) Arrow sampling system was used for the static and dynamic collection of BVOCs from the boreal forest, and samples were subsequently analysed on-site by gas chromatography-mass spectrometry (GC-MS). This system offers higher sampling capacity and improved robustness than the traditional equilibrium-based SPME techniques, such as SPME fibers. Field measurements were performed in summer 2017 at the Station for Measuring Ecosystem-Atmosphere Relations (SMEAR II) in Hyytiälä, Finland. Complementary laboratory tests were also performed to compare the SPME-based techniques under controlled experimental conditions and to evaluate the effect of temperature and relative humidity on their extraction performance. The most abundant monoterpenes and aldehydes were successfully collected. A significant improvement on sampling capacity was observed with the new SPME Arrow system when compared to SPME fibers, with collected amounts being approximately 2 times higher for monoterpenes and 7–8 times higher for aldehydes. BVOC species exhibited different affinities for the type of sorbent materials used (PDMS/Carbon WR vs. PDMS/DVB). Higher extraction efficiencies were obtained with dynamic collection prior to equilibrium regime, but this benefit during the field measurements was small probably due to the natural agitation provided by the wind. An increase in temperature and relative humidity caused a decrease in the amounts of analytes extracted under controlled experimental conditions, even though the effect was more significant for PDMS/Carbon WR than for PDMS/DVB. Overall, results demonstrated the benefits and challenges of using SPME Arrow for the sampling of BVOCs in the atmosphere.

Trends and applications in plant volatile sampling and analysis

“…SPME fibers are typically inserted into the hot injector of benchtop or portable GC instruments to release the collected compounds. An SPME device called the SPME Arrow (CTC Analytics AG, Zwingen, Switzerland) has recently been designed to provide more stability to the fiber and eliminate contamination and physical damage by allowing a complete enclosure of the fiber in the needle (Barreira et al, 2018). Owing to its increased stability and higher adsorbent capacity, the trapping device has been used for environmental VOC sampling with aerial drones (Ruiz-Jimenez et al, 2019).…”

Overview: Recent advances in the understanding of the northern Eurasian environments and of the urban air quality in China – a Pan-Eurasian Experiment (PEEX) programme perspective

“…To collect BVOC samples, a novel collection method offering portability and improved selectivity and capacity was developed. Solid-phase micro-extraction (SPME) arrow sampling (Feijó Barreira et al, 2018) can be used for static and dynamic collection of BVOCs under the field conditions. A significant improvement in sampling capacity was observed with the new SPME arrow system over SPME fibres.…”

Overview: Recent advances on the understanding of the Northern Eurasian environments and of the urban air quality in China - Pan Eurasian Experiment (PEEX) program perspective

“…For collecting BVOC samples, a novel collection method offering portability and improved selectivity and capacity was developed. A solid-phase microextraction (SPME) Arrow sampling (Barreira et al 2018) can be used for static and dynamic collection of BVOCs in the field conditions. A significant improvement on sampling capacity was observed with the new SPME Arrow system over SPME fibers.…”