Quantifying sesquiterpene and oxygenated terpene emissions from live vegetation using solid-phase microextraction...

Area of Science:

• Environmental Chemistry
• Atmospheric Chemistry
• Plant Science

Background:

• Biogenic terpenes are vital for ecosystem and atmospheric processes.
• Semi-volatile and reactive terpenes like sesquiterpenes and oxygenated terpenes are challenging to measure with traditional methods.

Purpose of the Study:

• To develop and validate an alternative method for quantifying biogenic terpene emissions from live plant branches.
• To overcome limitations of traditional air sampling for semi-volatile and reactive terpenes.

Main Methods:

• Utilized a flow-through enclosure coupled with solid-phase microextraction (SPME) fibers for sample collection.
• Employed gas chromatography-mass spectrometry (GC-MS) for analysis of collected terpenes.
• Optimized field collection and laboratory analysis procedures for polydimethylsiloxane-divinylbenzene (PDMS/DVB) SPME fibers.

Main Results:

• Successfully quantified emissions of methyl chavicol and various sesquiterpenes from a Ponderosa pine branch.
• Achieved low detection limits: 4.36 ppt for methyl chavicol and 16.6 ppt for beta-caryophyllene.
• SPME measurements showed good agreement with proton transfer reaction mass spectrometry (PTR-MS) for calibrated compounds.

Conclusions:

• The developed SPME method provides a reliable approach for field quantification of biogenic oxygenated terpene and sesquiterpene emissions.
• This technique minimizes sample loss, enhancing accuracy for volatile organic compound measurements.
• The method is suitable for studying plant-atmosphere interactions and atmospheric chemistry.