Analysis of sesquiterpene emissions by plants using solid phase microextraction.

Area of Science:

• Environmental Chemistry
• Plant Physiology
• Analytical Chemistry

Background:

• Sesquiterpenes (SQTs) are volatile organic compounds emitted by plants, playing roles in ecological interactions.
• Accurate quantification of SQT emissions is crucial for understanding plant responses and atmospheric chemistry.
• Traditional methods for SQT analysis can be complex and time-consuming.

Purpose of the Study:

• To characterize Solid Phase Microextraction (SPME) for sampling and analyzing plant-emitted sesquiterpenes (SQTs).
• To optimize SPME parameters, including fiber type, linear velocity, and relative humidity.
• To measure SQT emission rates from gray pine (Pinus sabiniana) and ponderosa pine (Pinus ponderosa).

Main Methods:

• Development of constant mixing ratio SQT standards using a capillary diffusion system.
• Characterization of polydimethylsiloxane SPME fibers for SQT absorption efficiency.
• Investigation of sample linear velocity and relative humidity effects on SPME SQT absorption.
• Application of SPME to quantify SQT emissions from two pine species under controlled conditions.

Main Results:

• Polydimethylsiloxane SPME fibers demonstrated effective absorption of various SQTs.
• Sample linear velocity and relative humidity were identified as significant factors influencing SQT absorption.
• Total SQT emission rates varied significantly between gray pine and ponderosa pine.
• Ponderosa pine exhibited higher SQT emission rates compared to gray pine, with a broader range of detected SQTs.

Conclusions:

• SPME is a viable and efficient technique for the sampling and analysis of plant-emitted sesquiterpenes.
• The characterized SPME method allows for reliable quantification of SQT emissions from different plant species.
• Findings provide valuable data on SQT emission profiles of gray and ponderosa pines, contributing to ecological and atmospheric studies.