Dynamic solid phase microextraction sampling for reactive terpenes in the presence of ozone

Area of Science:

• Analytical Chemistry
• Environmental Science

Background:

• Reactive terpenes and terpenoids are significant air pollutants.
• Ozone can interfere with the accurate measurement of these compounds.

Purpose of the Study:

• To evaluate dynamic gas sampling with solid phase microextraction (SPME) for recovering reactive terpenes and terpenoids in the presence of ozone.
• To determine the impact of ozone concentration, sampling time, and flow rate on recovery efficiency.

Main Methods:

• Dynamic gas sampling using solid phase microextraction (SPME).
• Analysis of limonene, α-terpineol, and dihydromyrcenol recovery under varying ozone concentrations (up to 100 ppb).
• Investigation of sampling times (typically 5 min) and flow rates (100-400 sccm).

Main Results:

• Achieved >80% recovery for terpenes at ozone levels up to 100 ppb.
• Higher ozone concentrations and longer sampling times reduced recovery.
• Typical recovery >90% with ppb-level detection limits at a 5 min sample time.
• Flow rate variations had minimal impact on sensitivity or recovery.
• Sampling from mixtures improved recovery compared to single compounds, likely due to ozone competition.

Conclusions:

• Dynamic SPME is a viable method for detecting and quantifying terpenes in reactive air environments.
• This technique is particularly useful for low vapor pressure compounds that might be lost with other methods.
• SPME offers improved terpene analysis in the presence of ozone, enhancing environmental monitoring capabilities.